V
V. Symbol for vanadium. hydrogen and chlorine both have a valence of 1,
oxygen a valence of 2, and nitrogen 3, the valence-
balancing principle gives the formulas HCl, H
2
,
vacancy. (1) A defect in a crystal due to the
NH
3
,Cl
2
O, NCl
3
, and N
2
O
3
, which indicate the rela-
absence of an atom in the lattice.
tive numbers of atoms of these elements in com-
See hole. (2) The absence of one or more electrons in
pounds that they form with each other. In inorganic
the outer shell of an atom.
compounds it is necessary to assign either a positive
or negative value to each valence number, so that
vacuole. Membrane-bound fluid-filled space
valence balancing will give a zero sum by algebraic
within a cell. In most plant cells, there is a single
addition. Negative numbers are called polar valence
large vacuole filling most of the cell’s volume.
numbers (–1 and –2). The valence of chlorine may
Some bacterial cells contain gas vacuoles.
be 1, +1, +3, +5, or +7, depending on the type of
compound in which it occurs. In organic chemistry
vacuum deposition. The process of coating a
only nonpolar valence numbers are used.
base material by evaporating a metal under high
See chemical bonding; oxidation; oxidation number;
vacuum and condensing it on the surface of the
coordination number.
material to be coated, which is usually another metal
or a plastic. Aluminum is most commonly used for
this purpose. The coatings obtained range in
valence electrons. The electrons in the outer-
thickness from 0.01 to as many as 3 mils. A vacuum
most shell of an atom determining chemical prop-
of about one-millionth atmosphere is necessary. The
erties.
process is used for jewelry, electronic components,
decorative plastics, etc. Thermally evaporated met-
valentinite. (antimony trioxide [ortho-rhom-
als and dielectric coatings can be effectively applied
bic]; white antimony).
to glass by this method. It is also called vacuum
CAS: 1309-64-4. Sb
2
O
3
.
coating and vacuum metallizing.
Properties: White or gray mineral, sometimes pale
red, white streak and adamantine or silky luster. D
vacuum distillation. Distillation at a pressure
5.57–5.76, Mohs hardness 2–3.
below atmospheric but not so low that it would be
Occurrence: Algeria, the former Yugoslavia, Italy,
classed as molecular distillation. Since lowering the
Germany.
pressure also lowers the boiling point, vacuum dis-
Use: Ore of antimony.
tillation is useful for distilling high-boiling and heat-
sensitive materials such as heavy distillates in petro-
leum, fatty acids, vitamins, etc.
valepotriate.
CAS: 18296-44-1. mf: C
22
H
30
O
8
.
Hazard: A poison.
vacuum forming. See thermoforming (2).
val. Abbreviation for value.
valeral. See valeraldehyde.
valacidin.
n-valeraldehyde. (valeric aldehyde; valeral;
CAS: 3930-19-6. C
26
H
24
N
4
O
8
.
amyl aldehyde; pentanal).
Properties: Brown to red solid. Soluble in polar
CAS: 110-62-3. CH
3
(CH
2
)
3
CHO.
solvents and alkaline solutions; insoluble in most
Properties: Colorless liquid. D 0.8095 (20/4C), fp
nonpolar solvents and acid solutions.
91C, bp 102–103C, refr index 1.3944 (20C), flash
Use: Antibiotic (used as a preservative for biological
p 54F (12.2C) (CC). Slightly soluble in water; solu-
specimens); embalming fluids.
ble in alcohol and ether.
Derivation: Oxidation of amyl alcohol, also by the
“Valclene” [Du Pont]. TM for clear fluoro-
Oxo process.
carbon formulations with slight ethereal odor. Non-
Hazard: Flammable, dangerous fire risk. TLV: 50
flammable.
ppm.
Use: Dry-cleaning fluids.
Use: Flavoring, rubber accelerators.
See isovaleraldehyde.
valence. A whole number that represents or de-
notes the combining power of one element with
another. By balancing these integral valence num-
valeranone.
bers in a given compound, the relative proportions CAS: 55528-90-0. mf: C
15
H
26
O.
of the elements present can be accounted for. If Hazard: A poison.
1309
1310VALERENAL
valerenal. oils, and as solvent for adhesives, insecticides, and
CAS: 4176-16-3. mf: C
15
H
22
O. lacquers.
Hazard: A poison.
valine. (-aminoisovaleric acid).
CAS: (
D-) 72-18-4. (CH
3
)
2
CHCH(NH
2
)COOH. An
valerenic acid.
essential amino acid.
CAS: 3569-10-6. mf: C
15
H
22
O
2
.
Properties: White, crystalline solid. Soluble in wa-
Hazard: A poison.
ter; verghtly soluble in alcohol; insoluble in ether;
shows the following optical isomers: (
DL-valine) Mp
valerianic acid. See valeric acid.
298C with decomposition. (
D-valine (natural iso-
mer): Mp 315C with decomposition. (
L-valine) Mp
valerian oil.
293C with decomposition.
Properties: Yellowish or brownish liquid; penetrat-
Derivation: Hydrolysis of proteins, synthesized by
ing odor. D 0.903–0.960, refr index 1.486 (20C).
the reaction of ammonia with -chloroisovaleric
Soluble in alcohol, ether, chloroform, acetone, ben-
acid. Available commercially as
D-, L-, or DL-valine.
zene, and carbon disulfide. Combustible. Chief con-
Use: Dietary supplement, culture media, biochemical
stituents: Pinene, camphene, borneol, and esters of
and nutritional investigations.
borneol and valeric acid.
Derivation: Distilled from roots and rhizome of Va-
“Valium” [Hoffmann-La Roche]. TM for
leriana officinalis.
diazepam.
Use: Tobacco perfume, industrial odorant, flavors.
valone. (2-isovaleryl-1,3-indanedione).
C
14
H
14
O
3
.
valeric acid. (valerianic acid; n-pentanoic
Properties: Yellow, crystalline solid. Mp 68C. Insol-
acid).
uble in water; soluble in common organic solvents.
CAS: 109-52-4. CH
3
(CH
2
)
3
COOH.
A blood anticoagulant.
Properties: Colorless liquid; penetrating odor and
Hazard: Toxic by ingestion.
taste. D 0.9394 (20/4C), bp 185.4C, refr index
Use: Pesticide, rodenticide.
1.4081 (20C), vap press 0.08 mm Hg (20C), fp
34C, flash p 205F (96C) (OC). Soluble in water,
vanadic acid. (1) meta-HVO
3
, (2) ortho-H
3
VO
4
,
alcohol and ether. Undergoes reactions typical of
(3) pyro-H
4
V
2
O
7
. These acids apparently do not exist
normal monobasic organic acids. Combustible.
in the pure state but are represented in the various
Derivation: With other C
5
acids by distillation from
alkali and other metal vanadates. Ordinarily, vanad-
valerian, by oxidation of n-amyl alcohol, numerous
ic acid implies vanadium pentoxide (vanadic acid
essential oils.
anhydride).
Grade: Technical, reagent.
Hazard: Toxic by ingestion, strong irritant to skin
vanadic acid anhydride. See vanadium
and tissue.
pentoxide.
Use: Intermediate for flavors and perfumes, ester-
type lubricants, plasticizers, pharmaceuticals, vinyl
vanadic(II) acid, trisodium salt. See sodi-
stabilizers.
um orthovanadate.
See isovaleric acid.
vanadic sulfate. See vanadyl sulfate.
valeric aldehyde. See n-valeraldehyde.
vanadic sulfide. See vanadium sulfide.
-valerolactone.
CAS: 108-29-2.
vanadinite. Pb
5
Cl(VO
3
). A natural chlorovana-
date of lead.
Properties: Ruby-red, orange-red, brown, yellow
solid; resinous to adamantine luster. Mohs hardness
3, d 6.7–7.1. Soluble in strong nitric acid.
Occurrence: New Mexico, Arizona, Africa, Scot-
Properties: Colorless liquid. D 1.0518 (25/25C), bp
land, the former U.S.S.R..
205–206.5C, crystallizing point 37C, flash p 205F
Use: Ore of vanadium and lead.
(96C) (COC), refr index 1.4301 (25C), surface ten-
sion 30 dynes/cm (25C), viscosity 2.18 cP (25C), pH
(anhydrous) 7.0 (pH of 10 solution in distilled water
vanadium.
4.2). Miscible with water and most organic solvents, CAS: 7440-62-2. V. Metallic element having atom-
resins, waxes, etc.; slightly miscible with zein, bees- ic number 23, group VB of the periodic table, aw
wax, petrolatum; immiscible with anhydrous glyc- 50.9414, valences of 2, 3, 4, 5; two natural isotopes.
erin, glue, casein, arabic gum, and soybean protein. Properties: Silvery-white ductile solid. D 6.11, mp
Combustible. 1900C, bp 3000C. Insoluble in water; resistant to
Use: Dye baths (coupling agent), brake fluids, cutting corrosion, but soluble in nitric, hydrofluoric, and
1311 VANADIUM PENTOXIDE
concentrated sulfuric acids; attacked by alkali,
vanadium hexacarbonyl. V(CO)
6
.
forming water-soluble vanadates. Acts as either a Properties: Blue-green powder. Sublimes easily at
metal or a nonmetal and forms a variety of complex 50C (15 mm Hg), paramagnetic, decomposes with-
compounds. out melting at 60–70C.
Source: Not found native; principal ores are patron- Hazard: Strong irritant to tissue; store under inert
ite, roscoelite, carnotite and vanadinite. Also from gas.
phosphate rock (Idaho, Montana, Arkansas). Use: Chemical intermediate, production of plating
Occurrence: Colorado, Utah, New Mexico, Arizo- compounds and fuel additives.
na, Mexico, and Peru.
Derivation: (1) Calcium reduction of vanadium
vanadium hexacarbonyl, sodium salt.
pentoxide yields 99.8+% pure ductile vanadium; (2)
(bisdiglymesodium hexacarbonyl vanadate).
aluminum, cerium, etc. reduction produces a less
Na(C
6
H
14
O
3
)
2
V(CO)
6
. A convenient though incom-
pure product; (3) solvent extraction of petroleum ash
plete name for the complex compound.
or ferrophosphorus slag from phosphorus produc-
Properties: Yellow solid. Mp 173–176C (with de-
tion; (4) electrolytic refining using a molten salt
composition). Soluble in water, alcohol, and ether;
electrolyte containing vanadium chloride.
slightly soluble in hydrocarbons; relatively inert to
Grade: 99.99% pure (electrolytic process), single
air but is stored and shipped under nitrogen.
crystals.
Hazard: Strong irritant to tissue.
Use: Target material for X rays, manufacture of alloy
Use: Source of vanadium hexacarbonyl by treatment
steels, vanadium compounds, especially catalyst for
with phosphoric acid under special conditions.
sulfuric acid and synthetic rubber.
See ferrovanadium.
vanadium nitride. VN.
Properties: Black solid. D 6.13, mp 2320C. Insolu-
ble in water; slightly soluble in aqua regia.
vanadium acetylacetonate.
Use: Refractory.
Properties: Blue to blue-green crystals. Decomposes
before melting.
vanadium oxydichloride. See vanadyl chlo-
Derivation: Reaction of vanadyl sulfate with acetyl-
ride.
acetone and sodium carbonate.
Use: Catalyst.
vanadium oxytrichloride.
CAS: 7727-18-6. VOCl
3
.
vanadium carbide. VC.
Properties: Lemon-yellow liquid. D 1.811 (32C), fp
Properties: Crystal. Mohs hardness 2800 kg/sq mm,
78.9C, bp 125–127C, nonionizing solvent. Dis-
d 5.77, mp 2800C, bp 3900C, resistivity 150 micro-
solves most nonmetals; dissolves and/or reacts with
ohm-cm (room temperature).
many organic compounds; hydrolyzes in moisture.
Use: Alloys for cutting tools, steel additive.
Hazard: Strong irritant to tissue.
Use: Catalyst in olefin polymerization (ethylenepro-
vanadium dichloride. (vanadous chloride).
pylene rubber) organovanadium synthesis.
CAS: 10213-09-9. VCl
2
.
Properties: Apple-green hexagonal plates. D 3.23
vanadium pentoxide. (vanadic acid anhy-
(18C). Soluble in alcohol and ether; decomposes in
dride).
hot water.
CAS: 1314-62-1. V
2
O
5
.
Derivation: From vanadium trichloride by heating in
Properties: Yellow to red crystalline powder. D
atmosphere of nitrogen.
3.357 (18C), mp 690C, bp (decomposes) 1750C.
Method of purification: Sublimation in nitrogen.
Soluble in acids and alkalies; slightly soluble in
Grade: CP.
water.
Hazard: Strong irritant to tissue.
Derivation: (1) Alkali or acid extraction from vana-
Use: Strong reducing agent, purification of hydrogen
dium minerals. (2) By igniting ammonium metava-
chloride from arsenic.
nadate. (3) From concentrated ferrophosphorus slag
by roasting with sodium chloride, leaching with
vanadium disulfide. V
2
S
2
.
water and purification by solvent extraction fol-
Properties: Solid. D 4.20, mp (decomposes). Solu-
lowed by precipitation and heating.
ble in hot sulfuric or nitric acids; insoluble in al-
Method of purification: Alkali solution, precipita-
kalies.
tion as ammonium metavanadate and ignition to
Use: Solid lubricant, electrode in lithium-based bat-
V
2
O
5
.
teries (experimental).
Grade: Commercial air-dried, commercial fused, CP
air-dried, CP fused.
vanadium ethylate. (C
2
H
5
O)
4
V. Hazard: Toxic by inhalation. TLV: 0.05 mg(V
2
O
5
)/
Properties: Dark-reddish-brown solid. m
3
; not classifiable as a human carcinogen.
Derivation: Reaction of vanadium chloride with so- Use: Catalyst for oxidation of sulfur dioxide in sulfu-
dium ethylate. ric acid manufacture, ferrovanadium, catalyst for
Use: Polymerization catalyst. many organic reactions, ceramic coloring material,
1312VANADIUM SESQUIOXIDE
vanadium salts, inhibiting UV transmission in glass, Hazard: Irritant.
photographic developer, dyeing textiles. Use: Catalyst for conversion of ethylene to ethanol.
See contact process.
vanadous chloride. See vanadium dichlo-
vanadium sesquioxide. See vanadium tri- ride.
oxide.
vanadyl chloride. (vanadium oxydichloride;
vanadyl dichloride; divanadyl tetrachloride).
vanadium sulfate. See vanadyl sulfate.
CAS: 10213-09-9. V
2
O
2
Cl
4
5H
2
O.
Properties: Green, deliquescent crystal. Usual tech-
vanadium sulfide. (vanadium pentasulfide;
nical product is a dark-green, syrupy mass 76–82%
vanadic sulfide). V
2
S
5
.
pure, or a solution. Slowly decomposed by water;
Properties: Black-green powder. D 3.0, decomposes
soluble in water, alcohol, and acetic acid; may react
on heating. Soluble in acids, alkali-metal sulfides
violently with potassium.
and alkalies; insoluble in water.
Grade: Technical.
Derivation: Action of hydrogen sulfide on vanadium
Hazard: Irritant.
chloride solution.
Use: Mordanting textiles.
Hazard: Toxic by inhalation (especially to animals).
Use: Vanadium compounds.
vanadyl sulfate. (vanadic sulfate; vanadium
sulfate).
vanadium tetrachloride.
CAS: 27774-13-6. VOSO
4
2H
2
O.
CAS: 7632-51-1. VCl
4
.
Properties: Blue crystals. Soluble in water.
Properties: Red liquid. D 1.816 (20C), fp 28C, bp
Derivation: Reduction of cold solution of concentra-
154C. Decomposes slowly to vanadium trichloride
ted sulfuric acid and vanadium pentoxide by sulfur
and chlorine below 63C. Soluble in absolute alcohol
dioxide gas.
and ether. Nonflammable.
Hazard: Irritant.
Derivation: Chlorination of ferrovanadium.
Use: Mordant, catalyst, aniline black preparation,
Method of purification: Distillation and fraction-
reducing agent, colorant in glasses and ceramics.
ation.
Hazard: Toxic by ingestion, inhalation, and skin
“Vanaquat” [Evans Vanodine]. TM for a
absorption. Open containers only in dry, oxygen-
cleaner and disinfectant for food processing equip-
free atmosphere or inert gas; wear goggles and pro-
ment.
tective clothing; corrosive to tissue.
Use: Preparation of vanadium trichloride, vanadium
dichloride, and organovanadium compounds.
“Vanason” [Evans Vanodine]. TM for a
tank sanitizer for dairy farm equipment.
vanadium tetraoxide. V
2
O
4
.
Properties: Blue-black powder. D 4.339, mp 1967C.
vancomycin hydrochloride.
Insoluble in water; soluble in alkalies and acids. Properties: Tan to brown powder; odorless; bitter
Derivation: (1) From vanadium pentoxide by oxalic taste. Soluble in water; moderately soluble in dilute
acid reduction. (2) From vanadium pentoxide by methanol; insoluble in higher alcohols, acetone,
carbon reduction. ether.
Hazard: Toxic and irritating. Derivation: Produced by Streptomyces orientalis
Use: Catalyst at high temperature. from Indonesian and Indian soil.
Grade: USP.
Use: Medicine (antibiotic).
vanadium trichloride.
CAS: 7718-98-1. VCl
3
.
Properties: Pink, deliquescent crystals. D 3.0 (18C),
“Vancote 2K” [Vanderbilt]. TM for a water-
decomposes on heating. Soluble in absolute alcohol borne epoxy fast dry shop primer.
and ether; decomposes in water.
Derivation: From vanadium tetrachloride boiling
van der Waals forces. (London dispersion
under reflux condenser.
force). Weak attractive forces acting between mole-
Hazard: Irritant.
cules. They are somewhat weaker than hydrogen
Use: Preparation of vanadium dichloride and organo-
bonds and far weaker than interatomic valences.
vanadium compounds.
They are involved in the van der Waals equation of
state for gases, which compensates for the actual
vanadium trioxide. (vanadium sesquioxide). volume of the molecules and the forces acting be-
CAS: 1314-34-7. V
2
O
3
. tween them. “Information regarding the numerical
Properties: Black crystals. D 4.87 (18C), mp 1970C. values of van der Waals forces is mostly semiempir-
Soluble in alkalies and hydrogen fluoride; slightly ical, derived with the aid of theory from an analysis
soluble in water. of chemical or physical data. Attempts to calculate
Derivation: From vanadium pentoxide by either hy- the forces from first principles have had a measure
drogen or carbon reduction. of success only for the simplest systems, such as
1313 “VARONIC”
HH, HeHe and a few others. When judging the pounds to three-dimensional and asymmetrical mo-
difficulties of such calculations, one must bear in lecular structure. This led to the development of
mind that the energies sought are of the same order stereochemistry. He was educated at the Universi-
of magnitude as those in the best atomic energy ties of Paris and Utrecht, where he received a doctor-
calculations.” (Henry Margenau). ate in 1874. He was a professor at Amsterdam,
See hydrogen bond; chemical bonding. Leipzig, and Berlin.
Van Dyke brown. (Cassel brown; Cologne
“Vapona” [Shell]. TM for an insecticide that
brown; Cologne earth; ulmin brown). A natural-
contains more than 93% 2,2-dichlorovinyl dimethyl
ly occurring pigment.
phosphate and less than 7% active, related com-
Derivation: Indefinite mixture of iron oxide and or-
pounds.
ganic matter. Obtained from bog-earth, peat depo-
See DDVP.
sits, or ochers that contain bituminous matter.
Hazard: As for dichlorovos.
Use: Pigment for artists’ colors and stains.
vapor. An air dispersion of molecules of a sub-
Van Dyke red. A brownish-red pigment con-
stance that is liquid or solid in its normal state, i.e., at
sisting of copper ferrocyanide; sometimes used to
standard temperature and pressure. Examples are
refer to red varieties of ferric oxide.
water vapor and benzene vapor. Vapors of organic
Use: Pigment.
liquids are also loosely called fumes.
See iron oxide red.
See evaporation; gas.
vanillin. (3-methoxy-4-hydroxybenzaldehyde;
vapor density. Weight of a vapor per unit vol-
vanillic aldehyde).
ume at any given temperature and pressure.
CAS: 121-33-5. (CH
3
O)(OH)C
6
H
3
CHO. The meth-
yl ether of protocatechuic aldehyde.
vapor-phase chromatography. See gas
Properties: White, crystalline needles; sweetish
chromatography.
smell. D 1.056, mp 81–83C, bp 285C. Soluble in 125
parts water, in 20 parts glycerol, and in 2 parts 95%
vapor pressure. (vap press; vap p; v.p.).
alcohol; soluble in chloroform and ether. Combus-
The pressure (often expressed in millimeters of mer-
tible.
cury, mm Hg) characteristic at any given tempera-
Derivation: (1) By extraction from the vanilla bean,
ture of a vapor in equilibrium with its liquid or solid
(2) from lignin contained in sulfite waste pulp li-
form.
quor.
Method of purification: Crystallization.
vapor tension. See vapor pressure.
Grade: Technical, USP, FCC.
Use: Perfumes, flavoring, pharmaceuticals, laborato-
varnish. (1) An organic protective coating similar
ry reagent, source of L-dopa.
to a paint except that it does not contain a colorant. It
may be composed of a vegetable oil (linseed, tung,
van Leeuwenhoek, Anton. (1632–1723). A
etc.) and solvent or of a synthetic or natural resin and
native of Holland, van Leeuwenhoek was a profes-
solvent. In the first case the formation of the film is
sional lens grinder. He developed the compound
due to polymerization of the oil and in the second to
optical microscope, which had been invented in
evaporation of the solvent. “Long-oil” varnishes
1590, to a point where he was able to obtain magnifi-
such as spar varnish have a high proportion of drying
cations up to 275 times. He was the first to observe
oil; “short-oil” types have a lower proportion, i.e.,
bacteria, spermatozoa, and other unicellular ani-
furniture varnishes. Spirit varnishes contain such
mals, which he described to the Royal Society of
solvents as methanol, toluene, ketones, etc. and of-
London.
ten also thinners such as naphtha or other light hy-
See optical microscope.
drocarbon. Flammable. (2) A hard, tightly adherent
deposit on the metal surfaces of automobile engines
“Vansil” [Vanderbilt]. TM for a calcium me-
resulting from resinous oxidation products of gaso-
talsillicate filler mineral.
line and lubricating oils.
Van Slyke determination. Treatment of pri-
varnish remover. See paint remover.
mary aliphatic amines and -amino acids with ni-
trous acid and volumetric determination of evolved
nitrogen.
“Varonic” [Crompton & Knowles]. TM for
ethoxylated primary amines. 2- to 30-mole adducts
van’t Hoff, Jacobus H. (1852–1911). A of primary fatty amines based on coco, soya, tallow,
Dutch chemist who received the first Nobel Prize for and oleic acid.
chemistry in 1901. A father of physical chemistry, Properties: Oil and water soluble.
he did research on decomposition and formation of Use: In textile industry and other emulsifier applica-
double salts. He related optically active carbon com- tions.
1314VARRENTRAPP REACTION
Varrentrapp reaction. Cleavage of oleic acid vegetable black. In general, any form of more
into palmitic and acetic acids by heating with molten or less pure carbon produced by incomplete com-
potassium hydroxide. The procedure has been ex- bustion or destructive distillation of vegetable mat-
tended to olefinic acids in general. ter, wood, vines, wine lees.
vasopressin. (-hypophamine; antidiuretic
vegetable dye. A colorant derived from a vege-
hormone). One of the hormones secreted by the table source, i.e., logwood, indigo, madder, etc.
posterior lobe of the pituitary gland. It causes in
blood pressure and an increase in water retention by
vegetable gum. See dextrin.
the kidney. Vasopressin is an octapeptide consisting
of eight amino acids.
vegetable oil. An oil extracted from the seeds,
Derivation: Synthetic, or from the posterior lobe of
fruit, or nuts of plants and generally considered to be
the pituitary of food animals.
a mixture of glycerides (e.g., cottonseed, linseed,
Grade: USP as an aqueous solution for injection.
corn, coconut, babassu, olive, tung, peanut, perilla,
Use: Medicine (antidiuretic).
oiticica, etc.). Many types are edible. Being plant-
derived products, vegetable oils are a form of bio-
vasopressin, 8-l-arginine-. See arginine va-
mass. Some are reported to be convertible to liquid
sopressin.
fuels by passing them over zeolite catalysts.
Use: Paints (as drying oils), shortenings, salad dress-
vat dye. A class of water-insoluble dyes that can
ings, margarine, soaps, rubber softeners, dietary
be easily reduced, i.e., vatted to a water-soluble and
supplements, pesticide carriers.
usually colorless leuco form in which they can readi-
ly impregnate fibers. Subsequent oxidation then
vegetable tanning. The tanning of leather by
produces the insoluble colored form that is remark-
plant extracts.
ably fast to washing, light, and chemicals. Examples
See tannic acid; tanning; wattle bark; quebracho.
are indigo (CI 73000) and Indanthrene Blue BFP (CI
69825). The reducing agents are usually an alkaline
vehicle. A term used in paint technology to indi-
solution of sodium hydrosulfite (Na
2
S
2
O
4
). Oxida-
cate the liquid portion of a paint, composed of drying
tion is by air, perborate, dichromate, etc.
oil or resin, solvent, and thinner, in which the solid
Use: For cotton, wool, and cellulose acetate.
components are dissolved or dispersed.
See paint.
vat printing assistant. A mixture of gums and
reducing and wetting agents used to carry the dye in
Venetian red. A high-grade ferric oxide pig-
printing fabrics with vat dyes. They assist in secur-
ment of a pure red hue. It is obtained either native as
ing penetration of the fabric and in converting the
a variety of hematite red or more often artificially by
dyes from a semileuco to a leuco state.
calcining copperas (ferrous sulfate) in the presence
of lime. The composition ranges from 15 to 40%
“Vatsol” [Cytec]. TM for a series of wetting
ferric oxide and from 60 to 80% calcium sulfate. The
agents made in several different grades and types:
40% ferric oxide is the “pure” grade and has a d 3.45.
OS, sodium isopropyl naphthalene sulfonic acid;
Grade: 20–40% ferric oxide.
OT, sodium dioctyl sulfosuccinate.
See iron oxide red.
vatting The process of solubilizing vat dyes in an
venturi. A type of flowmeter used for liquids or
aqueous solution of caustic soda and sodium hydro-
fine particulates. It is a tube like device having
sulfite.
broad, flaring ends and a narrow central portion, or
throat; this so constricts the passage of the fluid that
Vauquelin’s salt. (Pd(NH
3
)
4
)Cl
2
PdCl
2
.A
its rate of flow increases while the pressure de-
compound obtained by treating palladium chloride
creases. The difference in pressure thus created is a
with ammonia.
measure of the flow. Venturis are used in scrubbers,
liquid and solid conveying systems, pipelines, and
aircraft instrument control, as well as in numerous
VC. Abbreviation for vinyl chloride or vinylidene
chemical process techniques such as hydrogenation,
chloride.
chlorination, and oxidation. The hydrogenation
technology involves hydrogen entrainment by rapid
vector. (1) In biochemistry, an animal (insect,
flow of a liquid catalyst through the venturi nozzle.
rodent, etc.) that carries or transports infectious mi-
croorganisms. Typical vectors are rats and mosqui-
toes. (2) A DNA molecule known to replicate auton-
veratraldehyde. (vertraldehyde; 3,4-dime-
omously in a host cell, to which a segment of DNA thoxybenzaldehyde).
may be spliced to allow its replication. The current CAS: 120-14-9. (CH
3
O)
2
C
6
H
3
CHO.
types are plasmids, cosmids, YAC’s or a temperate- Properties: Mp 42–45C, bp 281C, flash p 235F
phage DNA. (112C), mw 166.18.
1315 “V-G-B”
veratric acid. (3,4-dimethoxybenzoic acid). Use: In latex paint formulations.
CAS: 93-07-2. (CH
3
O)
2
C
6
H
3
COOH.
Properties: Mw 182.18, mp 179–82C.
“Versa Guma” [Cargill]. TM for a xantham
gum specialty ingredient.
Use: In food formulation in a broad range of pH and
veratrole. (1,2-dimethoxybenzene; pyrocate-
temperatures.
chol dimethyl ether).
CAS: 91-16-7. C
6
H
4
(OCH
3
)
2
.
Properties: Colorless crystals or liquid. Mp 21–22C,
“Versamag” [Morton]. See “Novogel”.
bp 206–207C, d 1.084 (25/25C). Soluble in alcohol
and ether; slightly soluble in water.
“Versene” [Ashland].
Derivation: Treatment of catechol in methanol with
CAS: 62-33-9. TM for calcium disodium EDTA
dimethyl sulfate and caustic.
chelating agent.
Use: Medicine (antiseptic).
Use: Pharmaceuticals, foods, and biological applica-
tions to control oxidation, and chelate metal ions.
veratrum alkaloid. One of a group of alkaloids
used in medicine to relieve hypertension. They in-
“Versene Fe-3 Specific” [Dow]. TM for an
clude Veratrum viride (American hellebore).
iron specialty chelating agent; active ingredient is
Hazard: May have severe side effects.
sodium dihydroxyethylglycine; available as straw-
See alkaloid.
colored liquid or white powder.
verdigris. See copper acetate, basic.
“Versenex” 80 [Dow]. TM for pentasodium
salt of diethylenetriaminepentaacetic acid.
vermiculite. Hydrated magnesium-iron-alumi-
num silicate capable of expanding 6–20 times when
“Versenol” 120 [Dow]. TM for the trisodium
heated to 1093C. The platelets exhibit an active
salt of N-hydroxyethylethylenediaminetriacetic
curling movement when heated, hence the name.
acid (C
10
H
15
O
7
N
2
Na
3
).
Occurrence: Montana, North Carolina, South Caro-
Use: Organic chelating agent.
lina, Wyoming, Colorado, South Africa.
Properties: Platelet-type crystalline structure. High
verxite. (exfoliated hydrobiotite).
porosity, high void volume to surface area ratio, low
Properties: Thermally expanded (exfoliated) mag-
density, large range of particle size. Insoluble in
nesium-iron-aluminum silicate having a minimum
water and organic solvents; soluble in hot concentra-
of 98% purity and a bulk d of 5–7 lb/cu ft. Expansion
ted sulfuric acid. Water vapor adsorption capacity of
occurs by heating at 793C. Spongelike structure that
expanded vermiculite less than 1%, liquid adsorp-
absorbs liquids and permits reexpansion after com-
tion dependent on conditions and particle size,
pression to 70–80% of the original heat-expanded
ranges 200–500%. Noncombustible.
volume.
Grade: Unexpanded (ore concentrate), expanded
Use: Poultry feed in quantities less than 5% as a
(also called exfoliated), flake, activated.
nonnutritive bulking agent, pelleting or anti-caking
Use: Lightweight concrete aggregate, insulation,
agent and nutrient carrier in dog and ruminant feeds.
sound conditioning, fireproofing, plaster, soil condi-
For dog feeds the maximum permitted is 1.5%. La-
tioner, additive for fertilizers, seed bed for plants,
beling must state content when in excess of 1%.
refractory, lubricant, oil-well drilling mud. Filler in
See vermiculite.
rubber, paint, plastics. Wallpaper printing, removal
of strontium-90 from milk, absorption of oil spills
“Vespel” [Du Pont]. TM for fabricated parts,
on seawater, animal feed additive, packing, carrier
based on polyimide resin and diamond abrasive
for insecticides, catalyst and catalyst support, litter
wheels formulated with a high-temperature polyim-
for hatcheries, adsorbent.
ide binder.
See verxite.
vetiver oil. An essential oil with violetlike odor,
vermifuge. An agent used in veterinary medicine
strongly dextrorotatory.
to eliminate intestinal worms; an anthelmintic.
Use: Perfumery and fragrances.
vermilion, natural. See cinnabar.
“Vexar” [Du Pont]. TM for both low and
high-density polyethylene and polypropylene plas-
vernolepin. A sesquiterpene dilactone extracted
tic netting. Available in a wide variety of forms and
from leaves of an African plant Veronia hymenole-
colors for use in packaging.
pis.
Use: Biochemical research (inhibits tumor growth in
“V-G-B” [Uniroyal]. TM for reaction product
rats and reversibly retards plant growth).
of acetaldehyde and aniline.
Properties: Brown resinous powder. D 1.152, mp
“Versaflex” [Grace]. TM for polymer emul- 60–80C. Soluble in acetone, benzene, and ethylene
sion. dichloride; insoluble in water and gasoline.
1316“VIAGRA”
Use: Rubber antioxidant.
“Vikane” [Dow]. TM for sulfuryl fluoride.
“Viagra” [Pfizer]. (sildenafil citrate).
Vilsmeier-Haack reaction. Formulation of
CAS: 171599-83-0. mf: C
22
H
30
N
6
O
4
SC
6
H
8
O
7
.
activated aromatic or heterocyclic compounds with
Use: A treatment for male erectile dysfunction.
disubstituted formamides and phosphorus oxychlo-
ride.
“Vibrathane” [Great Lakes/Asia Pacific].
TM for a liquid castable, urethane prepolymer.
vinal fiber. Generic name for a manufactured
fiber in which the fiber-forming substance is any
long-chain synthetic polymer composed of at least
“Vibrin” [Uniroyal]. TM for resin composi-
50% by weight of vinyl alcohol units, CH
2
CH
2
O,
tions of polyesters and cross-linking monomers that
and in which the total of the vinyl alcohol units and
when catalyzed, will polymerize to infusible solid
any one or more of the various acetal units is at least
resins without evolving water or other by-products.
85% by weight of the fiber (Federal Trade Commis-
Use: Molding, laminating, impregnating, casting, au-
sion). It has good chemical resistance, low affinity
tomotive and aircraft structural parts, wall panels,
for water, good resistance to mildew and fungi.
table tops, coating for paper, boat hulls, chemically
Combustible.
inert tanks, large-diameter pipe.
Use: Fishing nets, stockings, gloves, hats, rainwear,
swimsuits.
vic-. Prefix meaning vicinal.
vinegar.
vicariance. Speciation which occurs as a result of
Properties: Brownish or colorless liquid. Dilute
the separation and subsequent isolation of portions
aqueous solution containing 4–8% acetic acid, de-
of an original population.
pending on source. Legal minimum is 4%. Also
contains low percentages of alcohols and mineral
vicinal. (vic-). Neighboring or adjoining posi-
salts. Nonflammable.
tions on a carbon ring or chain; the term is used in
Derivation: (1) Bacterial fermentation of apple ci-
naming derivatives with substituting groups in such
der, wine, or other fruit juice. (2) Fermentation of
locations in a structural formula or molecule. For
malt or barley. The fermenting agent is usually a
example, vicinal locations in the molecule shown
mold, e.g., Mycoderma aceti, generally known as
are occupied by the hydrogen atoms and the hydrox-
“mother.” Either type can be distilled to remove
yl groups:
color and other impurities and is then called white
vinegar.
Use: Mayonnaise, salad dressings, pickled foods,
preservative, medicine (antifungal agent), latex
coagulant.
“Vinoflex” [BASF]. TM for vinyl chloride
Victoria blue. (CI 44045). C
33
H
31
N
3
HCl.
homo- and copolymers.
Properties: Bronze colored, crystalline powder. Sol-
uble in hot water, alcohol, or ether.
“Vinsol” [Aqualon]. TM for a series of low-
Derivation: Michler’s ketone is condensed with phe-
cost, dark, brittle, thermoplastic resins; ruby-red by
nyl--naphthylamine.
transmitted light, dark-brown by reflected light.
Use: Dyeing silk, wool, and cotton; biological stain;
Available in solid form, flakes, fine powder, and
dye intermediate for complex acid pigment toners.
aqueous dispersion.
Use: Adhesives, asphalt emulsions, electrical insula-
Victoria green. See malachite green.
tion, inks, plastics.
“Victory” [Baker Petrolite]. TM for a plastic
vinyl. See vinyl compound.
grade of petroleum microcrystalline wax.
vinyl acetate.
vicuna. A soft, wool-like fiber obtained from a
CAS: 108-05-4. CH
3
COOCH:CH
2
. Raw material
South American animal similar to the llama.
for polyvinyl resins.
Use: Specialty high-grade coats, sweaters, etc. Com-
Properties: Colorless liquid stabilized with either
bustible.
hydroquinone or diphenylamine inhibitors. The hy-
droquinone stabilized material can be polymerized
vidarabine. Generic name for ara-A.
without redistillation. The DPA-stabilized material
must be distilled before polymerization. D 0.9345
“Vigofac 6” [Pfizer]. TM for an unidentified (20/20C), fp 100.2C, bp 73C, refr index 1.3941,
growth factor for addition to animal feeds. Derived bulk d 7.79 lb/gal, flash p 30F (1.1C) (TOC), aut-
from dried streptomyces fermentation solubles. oign temp 800F (426.6C). Soluble in most organic
1317 VINYLCYCLOHEXENE
solvents including chlorinated solvents; insoluble in Use: Synthesis, copolymerization.
water.
Derivation: (1) Vapor-phase reaction of ethylene,
vinyl butyrate.
acetic acid, and oxygen, with a palladium catalyst.
CAS: 123-20-6. CH
2
:CHOOCC
3
H
7
.
(2) Vapor-phase reaction of acetylene, acetic acid,
Properties: Liquid. D 0.9022 (20/20C), bp 116.7C,
and oxygen, with zinc acetate catalyst. (3) From
fp 86.8C, flash p 68F (20C) (OC). Very slightly
synthesis gas. soluble in water.
Grade: Technical. Hazard: Flammable, dangerous fire risk.
Hazard: Flammable, dangerous fire risk. Flammable Use: Polymers, emulsion paints.
limits in air 2.6–13.4%. Toxic by inhalation and
ingestion. TLV: 10 ppm, STEL: 15 ppm; animal
n-vinylcarbazole. C
2
H
8
NHC:CH
2
.
carcinogen.
Properties: Liquid. Combustible.
Use: Polyvinyl acetate, polyvinyl alcohol, polyvinyl
Derivation: From acetylene and carbazole.
butyral, and polyvinyl chloride-acetate resins, used
Use: Polymerizes to form heat-resistant and insulat-
particularly in latex paints, paper coating, adhesives,
ing resins somewhat similar to mica in dielectric
textile finishing, safety glass interlayers. A vinyl
properties.
acetate-ethylene copolymer is available for special-
See polyvinyl carbazole.
ty products.
See polyvinyl acetal; polyvinyl acetate; polyvinyl
vinyl cetyl ether. See cetyl vinyl ether.
alcohol; polyvinyl chloride-acetate.
vinyl chloride. (VC; chloroethene; chloroe-
vinylacetonitrile. See allyl cyanide.
thylene).
CAS: 75-01-4. CH
2
:CHCl. The most important vi-
vinylacetylene. C
4
H
4
or H
2
C:CHC:CH. The di-
nyl monomer.
mer of acetylene, formed by passing it into a solution
Properties: Compressed gas, easily liquefied, ethe-
of cuprous and ammonium chlorides in hydrochlo-
real odor, usually handled as liquid. Phenol is added
ric acid.
as a polymerization inhibitor. D 0.9121 (liquid at 20/
Properties: Colorless gas or liquid. D 0.6867 (20C),
20C), bp 13.9C, fp 159.7C, vap press 2300 mm
bp 5C. Combustible.
Hg (20C), flash p 108F (77C), autoign temp 882F
Use: Intermediate in manufacture of neoprene and for
(472C). Slightly soluble in water; soluble in alcohol
various organic syntheses.
and ether.
See divinyl acetylene.
Derivation: (1) Dehydrochlorination of ethylene di-
chloride; (2) reaction of acetylene and hydrogen
vinyl acrylate. See ethenyl 2-propenoate. chloride, either as liquids or gases.
Grade: Technical, pure 99.9%.
Hazard: Explosive limits in air 4–22% by volume.
vinyl alcohol. (ethenol). CH
2
:CH
2
O. Unstable
An extremely toxic and hazardous material by all
liquid; isolated only in the form of its esters or the
avenues of exposure. A carcinogen. TLV: TWA 5
polymer, polyvinyl alcohol.
ppm. Use in aerosol sprays prohibited.
Use: Polyvinyl chloride and copolymers, organic
vinylation. The formation of a vinyl derivative
synthesis, adhesives for plastics.
by reaction with acetylene. Thus vinylation of alco-
hols yields vinyl ethers such as vinyl ethyl ether,
vinyl-2-chloroethyl ether.
C
2
H
5
OC
2
H
3
.
CAS: 110-75-8. CH
2
:CHOCH
2
CH
2
Cl.
Properties: Liquid. D 1.0498 (20C), bp 109.1C, fp
vinyl bromide.
69.7C, flash p 80F (26.6C) (OC). Very slightly
CAS: 593-60-2. CH
2
CHBr.
soluble in water.
Properties: Gas. Fp 138C, bp 15.6C, d 1.51.
Hazard: Flammable, dangerous fire risk.
Hazard: A carcinogen. TLV: 5 ppm; suspected hu-
man carcinogen.
vinyl compound. A compound having the vinyl
Use: Flame-retarding agent for acrylic fibers.
grouping (CH
2
==CH), specifically vinyl chloride,
vinyl acetate, and similar esters but also referring
vinyl-n-butyl ether. (n-butyl vinyl ether;
more generally to compounds such as styrene
BVE).
C
6
H
5
CH==CH
2
, methyl methacrylate CH
2
==C(CH
3
)
CAS: 111-34-2. CH
2
:CHOC
4
H
9
.
COOCH
3
, and acrylonitrile CH
2
==CHCN. The vinyl
Properties: Liquid. D 0.7803 (20C), bp 94.1C, fp
compounds are highly reactive, polymerize easily,
113C, refr index 1.3997, flash p 15F (9.4C) (OC),
and the basis of a number of important plastics.
bulk d 7.45 lb/gal (20C). Slightly soluble in water;
soluble in alcohol and ether.
vinyl cyanide. See acrylonitrile.
Derivation: Reaction of acetylene with n-butyl al-
cohol.
Grade: Technical (98%).
vinylcyclohexene. (1-vinylcyclohexene-3; 4-
Hazard: Flammable, dangerous fire risk. vinylcyclohexene-1; cyclohexenylethylene).
1318VINYLCYCLOHEXENE
CAS: 100-40-3. CH
2
:CHCHCH
2
CH:CHCH
2
CH
2
.A vinyl ethyl ether. (ethyl vinyl ether; EVE).
butadiene dimer.
CAS: 109-92-2. CH
2
:CHOC
2
H
5
.
Properties: Liquid. D 0.8303 (20/4C), fp 108.9C,
Properties: Colorless liquid. Extremely reactive, can
bp 128C, refr index 1.464 (20C), flash p 70F (21.2C)
be polymerized in liquid or vapor phase. D 0.754
(TOC), autoign temp 517F (269C). Temperatures
(20/20C), bulk d 6.28 lb/gal (20C), fp 115.0C,
above 80F (26.6C) and prolonged exposure to oxy-
viscosity 0.22 cP (20C), refr index 1.3739, flash p
gen-containing gases should be avoided because
50F (46C), autoign temp 395F (201.6C). Slightly
these conditions lead to discoloration and gum for-
soluble in water (0.9% by weight). Commercial ma-
mation.
terial contains inhibitor to prevent premature poly-
Grade: Technical 95%, pure 99%, research.
merization. Often stored underground to minimize
Hazard: TLV: 0.1 ppm (skin); Animal Carcinogen.
vapor losses.
Flammable, dangerous fire risk. Narcotic in high
Derivation: Reaction of acetylene with ethanol.
concentration.
Grade: Technical.
Use: Polymers, organic synthesis.
Hazard: Highly flammable, severe fire and explo-
sion risk, explosive limits in air 1.7–28%.
Use: Copolymerization, intermediate.
vinylcyclohexene dioxide. (vinylcyclohexane
dioxide).
vinyl ethyl ether polymer. See 5-(3 or 6-
CAS: 106-87-6.
oxo-1-cyclohexen-1-yl)-5-ethylbarbituric acid.
C
H
2
CH
OC
6
H
9
O.
vinyl-2-ethylhexoate.
Properties: Colorless liquid. D 1.098 (20/20C), bp
CAS: 94-04-2. CH
2
==CHOOCCH(C
2
H
5
)C
4
H
9
.
227C, refr index 1.4782 (20C), viscosity 7.77 cP
Properties: Liquid. D 0.8751 (20/20C), bp 185.2C,
(20C), flash p 230F (110C). Combustible.
fp 90C, flash p 165F (73.9C) (OC). Insoluble in
Hazard: Toxic by ingestion and skin absorption,
water. Combustible.
strong irritant to skin and tissue. TLV: 0.1 ppm;
Use: Polymers, emulsion paints.
animal carcinogen.
Use: Polymers, organic synthesis.
vinyl-2-ethylhexyl ether.
CAS: 103-44-6. CH
2
==CHOCH
2
CH(C
2
H
5
)C
4
H
9
.
vinylcyclohexene monoxide. (vinylcyclo-
Properties: Liquid. D 0.8102 (20/20C), bp 177.7C,
hexane monoxide). CH
2
:CHC
6
H
9
O.
fp 100C, flash p 135F (57.2C) (OC), autoign temp
Properties: Liquid. D 0.9598 (20/20C), bp 169C, fp
395F (201.6C). Insoluble in water. Combustible.
100C, flash p 136F (57.8C), viscosity 1.69 cP
Hazard: Moderate fire and explosion risk.
(20C). Very slightly soluble in water. Combustible.
Use: Intermediate for pharmaceuticals, insecticides,
Hazard: Moderate fire risk. Irritant.
adhesives, viscosity index improver.
Use: Polymers, organic synthesis.
2-vinyl-5-ethylpyridine.
vinyl ether. (divinyl ether; divinyl oxide).
(CH
2
==CH)C
5
H
3
N(C
2
H
5
).
CAS: 109-93-3. CH
2
:CHOCH:CH
2
.
Properties: Liquid. D 0.9449 (20/20C), bp 138C
Properties: Colorless liquid; characteristic odor. D
(100 mm Hg), vap press 0.1 mm Hg (20C), fp
0.769, bp 39C, refr index 1.3989 (20C), flash p 22F
50.9C, flash p 200F (93.3C) (COC). Insoluble in
(30C), autoign temp 680F (360C). Slightly soluble
water. Combustible.
in water; miscible with alcohol, acetone, chloro-
Use: Copolymer, synthesis.
form, and ether. Must be protected from light.
Derivation: Treatment of dichloroethyl ether with
vinyl fluoride. (fluoroethylene).
alkali.
CAS: 75-02-5. CH
2
==CHF.
Grade: NF (contains 96–97% vinyl ether, remainder
Properties: Colorless gas. Bp 72C. Insoluble in
dehydrated alcohol).
water; soluble in alcohol and ether.
Hazard: Flammable, severe fire and explosion risk;
Hazard: Flammable, dangerous fire and explosion
explosive limits in air 1.7–27%. Toxic by inhalation,
risk. Toxic by inhalation. TLV: 2.6 mg(F)/m
3
.
overexposure may be fatal.
Use: Monomer.
Use: Copolymer with 3–5% polyvinyl chloride for
See polyvinyl fluoride.
plastic products such as clear plastic bottles; medi-
cine (anesthetic, for brief operations only).
vinylheptacyclotetrasiloxane.
CAS: 3763-39-1. mf: C
9
H
24
O
4
Si
4
.
vinyl--ethoxyethyl sulfide.
Hazard: Low toxicity by ingestion. A severe skin
CH
2
:CHSCH
2
CH
2
OC
2
H
5
.
irritant.
Properties: Colorless liquid; pungent, camphorlike
odor. D 0.9532 (15C), bp 65C (8 mm Hg).
vinylidene chloride. (VC).
Use: Organic synthesis.
CAS: 75-35-4. CH
2
==CCl
2
.
Properties: Colorless liquid. Fp 122.53C, bp 37C,
vinylethylene. See butadiene. flash p 14F (10C) (OC), autoign temp 856F
1319
n
-VINYL
(457C), readily polymerizes. Insoluble in water.
vinyl methyl ether. (methyl vinyl ether; me-
Commercial product contains small proportion of
thoxyethylene; MVE).
inhibitor.
CAS: 107-25-5. CH
2
==CHOCH
3
.
Hazard: Flammable, dangerous fire risk, explosive
Properties: Colorless compressed gas, or colorless
limits in air 5.611.4%. Toxic by inhalation. TLV: 5
liquid. D 0.7500 (20/20C), bp 6.0C, vap press 1052
ppm; STEL 20 ppm; animal carcinogen.
mm Hg (20C), flash p 60F (51C), fp 121.6C.
Use: Copolymerized with vinyl chloride or acryloni-
Slightly soluble in water; soluble in alcohol and
trile to form various kinds of saran. Other copoly-
ether; easily polymerized. Commercial material
mers are also made. Adhesives; component of syn-
contains a small proportion of polymerization inhib-
thetic fibers.
itor.
See saran.
Derivation: Catalytic reaction of acetylene and
methanol.
Grade: Technical (95% min), pure.
vinylidene chloride-butyl acrylate
Hazard: Highly flammable, severe fire and explo-
copolymer.
sion risk, explosive limits in air 2.6–39%.
CAS: 9011-09-0. mf: (C
7
H
12
O
2
C
2
H
2
Cl
2
)
x
Use: Copolymers used in coatings and lacquers;
Hazard: Low toxicity by ingestion.
modifier for alkyl, polystyrene, and ionomer resins;
plasticizer for nitrocellulose and adhesives.
vinylidene fluoride. (1,1-difluoroethylene).
See polyvinyl methyl ether.
CAS: 75-38-7. H
2
C==CF
2
. A monomer.
Properties: Colorless gas; faint ethereal odor. Bp
vinyl methyl ketone. (3-buten-2-one; methyl
83C (1 atm), fp 144C (1 atm), d (liquid) 0.617
vinyl ketone).
(24C). Slightly soluble in water; soluble in alcohol
CAS: 78-94-4. CH
3
COCH==CH
2
.
and ether.
Properties: Colorless liquid. D 0.8636 (20/4C), bp
Derivation: Interaction of hydrogen with dichlorodi-
80C, flash p 20F (6.6C) (CC). Soluble in water and
fluoroethane.
alcohols.
Grade: 99% min purity.
Hazard: Flammable, dangerous fire risk. Skin and
Hazard: Flammable, dangerous fire risk, explosive
eye irritant.
limits in air 5.5–21%. Toxic by inhalation. TLV: 2.5
Use: Monomer for vinyl resins, component of ionom-
mg(F)/m
3
.
er resins, intermediate in steroid and vitamin A syn-
Use: Polymers and copolymers, chemical intermedi-
thesis, alkylating agent.
ate.
See polyvinylidene fluoride.
2-(vinyloxy)ethyl nitrate. See ethylene gly-
col mononitrate vinyl ether.
vinylidene resin. (polyvinylidene resin). A
polymer in which the unit structure is (H
2
CCX2),
vinyl plastics. See polyvinyl resins.
in which X is usually chlorine, fluorine, or cyanide
radical. Examples are saran and “Vitron” A.
vinyl propionate. CH
2
==CHOOCC
2
H
5
.
Properties: Liquid. D 0.9173 (20/20C), bp 95.0C, fp
vinyl isobutyl ether. (isobutyl vinyl ether;
81.1C, flash p 34F (1.1C) (OC). Almost insoluble
IVE).
in water.
CAS: 109-53-5. CH
2
==CHOCH
2
CH(CH
3
)
2
.
Hazard: Flammable, dangerous fire risk.
Properties: Colorless liquid. D 0.7706 (20/20C), bp
Use: Polymers, emulsion paints.
83.3C, vap press 68 mm Hg (20C), fp 132C, refr
index 1.3938, flash p 15F (9.4C) (OC). Very slight-
vinylpyridine. C
5
H
4
NCH==CH
2
.
ly soluble in water; soluble in alcohol and ether;
Properties: Colorless liquid. Boils with resinifica-
easily polymerized.
tion at 159C, d 0.9746 (20C), refr index 1.5509
Derivation: Catalytic union of acetylene and isobu-
(20C). Dissolves in water to extent of 2.5%; water
tyl alcohol.
dissolves in it to 15%; soluble in dilute acids, hydro-
Method of purification: Washing with water, drying
carbons, alcohols, ketones, esters. Commercial ma-
in the presence of alkali, and distillation from metal-
terial contains inhibitor. Combustible.
lic sodium.
Hazard: Irritant to skin and eyes.
Grade: Technical.
Use: Elastomers and pharmaceuticals. Latex used as
Hazard: Flammable, dangerous fire risk.
tire cord binder (41% solids). The latex is copoly-
Use: Polymer and copolymers used in surgical adhe-
merized with butadiene-styrene.
sives, coatings, and lacquers; modifier for alkyd and
polystyrene resins; plasticizer for nitrocellulose and
n-vinyl-2-pyrrolidone.
other plastics; chemical intermediate.
CAS: 88-12-0.
vinylmagnesium chloride. CH
2
==CHMgCl.
Usually supplied dissolved in tetrahydrofuran. CH
2
==CHN
CH
2
CH
2
CH
2
CO.
Use: Grignard reagent. Properties: Colorless liquid. Bp 148C (100 mm Hg),
13201-VINYL-2-PYRROLIDONE
mp 13.5C, flash p 209F (98.3C) (COC), d 1.04. weight of vinyl chloride units, CH
2
CHCl (Federal
Combustible. Trade Commission). It has good resistance to chem-
Derivation: From acetylene and formaldehyde by icals, bacteria, moths; unaffected by water and sun-
high-pressure synthesis. light; low softening point. Tenacity 3.1 g/denier,
Hazard: Irritant and narcotic. difficult to ignite, self-extinguishing.
Use: Polyvinylpyrrolidone, organic synthesis.
See polyvinyl chloride.
1-vinyl-2-pyrrolidone crosslinked insoluble
vioform. (iodochloroxyquinoline). Odorless,
polymer. See polyvinylpolypyrrolidone.
nonirritant, sterilizable substitute for iodoform.
vinyl stabilizer. A substance added to vinyl
violanthrone. See dibenzanthrone.
chloride resins during compounding, to retard the
rate of deterioration caused by formation of hydro-
Violet #1. An FD&C color used for meat grad-
gen chloride. Many combine readily with hydrogen
ing, cosmetics, beverages, etc. It is a triphenylmeth-
chloride but do not otherwise interfere with the
ane dye banned by the FDA in 1973 because of
properties and uses of the final product. Amines,
carcinogenic risk.
basic oxides, and metallic soaps are commonly used.
violet gentian. See methyl violet.
vinyl stearate. CH
3
(CH
2
)
16
COOCH==CH
2
.
Properties: White waxy solid. Mp 28–30C, bp 175C
viomycin. An antibiotic produced by Streptomy-
(3 mm Hg), d 0.9037 (20/20C), refr index
ces puniceus. Unique among antibiotics in that it is
1.4355–1.4362 (55C), iodine no. 80–82. Insoluble
more active against acid-fast organisms than against
in water and alcohol; moderately soluble in ketones
other groups. Mycobacteria are most sensitive to
and vegetable oils; soluble in most hydrocarbon and
viomycin, and the antibiotic is active against strains
chlorinated solvents. Combustible.
of Mycobacterium tuberculosis, which are resistant
Use: Plasticizer (copolymerizer), lubricant.
to other antibiotics. Available commercially as sul-
fate.
vinylstyrene. See divinyl benzene.
viosterol. Irradiated ergosterol.
vinyl toluene. (methyl styrene).
CAS: 25013-15-4. CH
2
==CHC
6
H
4
CH
3
.
“Vipex 19” [Crowley]. TM for a specialty
Properties: Colorless liquid. Fp 76.8C, bp
formulated high viscosity oil.
170–171C, d 0.890 (25/25C), bulk d 7.41 lb/gal, refr
Use: In asphalt pavement emulsified rejuvenation.
index 1.534 (34C), flash p 130F (54.4C) (CC), aut-
oign temp 921F (494C). Very slightly soluble in
viral vector. A viral DNA altered so that it can
water; soluble in methanol, ether. Combustible.
act as a vector for recombinant DNA.
Hazard: Moderate fire risk. TLV: 50 ppm; STEL
100 ppm; not classifiable as a human carcinogen.
viridogrisein. See etamycin.
Use: Solvent, intermediate.
virion. A single virus particle.
vinyl trichloride. See 1,1,2-trichloroethane.
Virtanen, Arrturi I. (1895–1973). A Finnish
vinyltrichlorosilane.
biochemist who won the Nobel Prize in 1945. His
CAS: 75-94-5. CH
2
CHSiCl
3
.
work was primarily concerned with research in nu-
Properties: Colorless or pale-yellow liquid. Bp
trition and agriculture. He made important discov-
90.6C, d 1.265 (25/25C), refr index 1.432 (20C),
eries regarding prevention of fodder spoilage and
flash p 16F (8.89C). Readily hydrolyzed with lib-
bacterial fermentation as well as nitrogen metabo-
eration of hydrogen chloride; polymerizes easily;
lism in plants. His Ph.D. was awarded at the Univer-
soluble in most organic solvents; reacts with al-
sity of Helsinki and followed by an illustrious career
cohol.
that included awards throughout Scandanavia.
Derivation: Reaction of acetylene and trichlorosi-
lane (peroxide catalyst), reaction of trichlorosilane
virus. An infectious agent composed almost en-
with vinyl chloride.
tirely of protein and nucleic acids (nucleoprotein).
Grade: Technical.
Viruses can reproduce only within living cells and
Hazard: High by ingestion and inhalation, strong
are so small that they can be resolved only with an
irritant to tissue. Flammable, dangerous fire risk.
electron microscope. Since they pass through filters
Use: Intermediate for silicones, coupling agent in
that retain bacteria, they are often called filterable
adhesives and bonds.
viruses. Tobacco mosaic was the first virus to be
crystallized and isolated (Dr. W. M. Stanley, 1935);
vinyon. Generic name for a manufactured fiber in it contains some 2000 protein molecules in a se-
which the fiber-forming substance is any long-chain quence of 158 amino acids (mw 40,000,000). Bushy
synthetic polymer composed of at least 85% by stunt virus found in tomato plants has a molecular
1321 VITAMIN
weight of 7,600,000. First synthesis of a virus was shear. A liquid has a viscosity of one poise if a force
reported in 1967. of 1 dyne/square centimeter causes two parallel liq-
Viruses differ from organisms in that they are only uid surfaces one square centimeter in area and one
half alive; they lack metabolism, are unable to uti- centimeter apart to move past one another at a veloc-
lize oxygen, to synthesize macromolecules, to grow, ity of 1 cm/second. One poise equals 100 centi-
or to die. They are parasites, relying on a living host poises. Viscosity in centipoises divided by the liquid
cell. They account for many diseases, including density at the same temperature gives kinematic
mumps, measles, scarlet fever, smallpox, influenza, viscosity in centistokes (cs). One hundred centi-
and possibly the common cold. Their shapes are stokes equal one stoke. To determine kinematic vis-
similar to those of bacteria (rods, spheres, fila- cosity, the time is measured for an exact quantity of
ments). They have the ability to mutate; they are also liquid to flow by gravity through a standard capil-
antigenic and thus initiate formation of antibodies. lary.
Some act as bacteriophages. A direct relation be- Water is the primary viscosity standard with an
tween virus and cancer has been shown, the DNA of accepted viscosity at 20C of 0.010019 poise. Hydro-
the virus becoming irreversibly bound to the DNA carbon liquids such as hexane are less viscous. Mo-
of the affected cells. See bacteria; deoxyribonu- lasses may have a viscosity of several hundred centi-
cleic acid. stokes, while for a very heavy lubrication oil the
viscosity may be 100 centistokes. There are many
empirical methods for measuring viscosity. See
viscometer. (viscosimeter). A device for mea-
Saybolt Universal Viscosity; viscometer.
suring the viscosity of a liquid. The types most
widely used are the Engler, Saybolt, and Redwood,
which indicate viscosity by the rate of flow of the
viscosity index improver. A lubricating-oil
test liquid through an orifice of standard diameter or additive that has the effect of increasing the viscosi-
the flow rate of a metal ball through a column of the ty of the oil in such a way that it is greater at high
liquid; other types utilize the speed of a rotating temperature than at low temperature. Agents used
spindle or vane immersed in the test liquid. The for this purpose are polymers of alkyl esters of meth-
liquids commonly measured are lubricating oils and acrylic acid, polyisobutylenes, etc.
the like; heavier (non-Newtonian) liquids such as
paints and paper coatings require more complex
viscosity, kinematic. See viscosity.
devices, e.g., Brookfield and Krebs-Stormer.
See viscosity.
“Vistac A” [AKZO]. TM for a series of syn-
thetic hydrocarbon polymers.
viscose process. The best-known process for
Use: Rubber-base adhesives and cements; latex and
making regenerated cellulose (rayon) by converting
asphalt emulsions.
cellulose to the soluble xanthate, which can be spun
into fibers and then reconverted to cellulose by treat-
visual purple. See rhodopsin.
ment with acid. Wood pulp is steeped with 17–20%
caustic soda; the resulting alkali cellulose is pressed
vitamin. Any of a number of complex organic
to remove excess liquor and the soluble - and -
compounds, present in natural products or made
cellulose, and then shredded and aged. It is then
synthetically, which are essential in small propor-
treated with carbon disulfide and sodium hydroxide
tions in the diet of animals and humans. Some are fat
to form an orange, viscous solution of cellulose
soluble (A, D, K); others are water soluble (B com-
xanthate. After filtration and deaeration, this solu-
plex, C). Their precursors are called provitamins. A
tion (viscose) is forced through minute spinnerette
normal diet usually contains sufficient vitamins for
openings (or long slit dies in the case of cellophane)
health, although older people, the ill, young, or in-
into a bath containing sulfuric acid and various salts
firm may require different standards. Their usual use
such as sodium and zinc sulfate. The salts cause the
in medicine is restricted to correction of specific
viscose to gel immediately, forming a fiber or film of
metabolic deficiencies. Some authorities believe
sufficient strength to permit it to be drawn through
that habitual intake of standard vitamin preparations
the bath under tension. At the same time the sulfuric
readily available on the market is of little if any
acid decomposes the xanthate, converting the fibers
nutritional benefit. The following list of cross-refer-
to cellulose, in which form they are washed and
ences will serve to locate technical information
dried.
about the various vitamin entries in this book:
See rayon; cellophane.
Vitamin A. See carotene; cryptoxanthin; reti-
nol; 3-dehydroretinol; provitamin.
viscosification. Increasing the viscosity of a
Vitamin B. See vitamin B complex; thiamine;
liquid.
riboflavin; niacin; panthothenic acid; biotin; cy-
anocobalamin; pyridoxine; folic acid; inositol.
viscosimeter. See viscometer.
Vitamin C. See ascorbic acid.
Vitamin D. See ergosterol; ergocalciferol; cho-
viscosity. The internal resistance to flow exhib- lecalciferol.
ited by a fluid; the ratio of shearing stress to rate of Vitamin E. See tocopherol.
1322VITAMIN A
Vitamin K. See phytonadione; menadione; their glassy appearances. Sulfuric acid was called oil
phthiocol. of vitriol. Derived from vitrum (glass).
Vmax. The maximum velocity of an enzymatic
vitamin A
1
, anhydrous. See all-trans
-anhy-
reaction when the binding site is saturated with sub-
droretinol.
strate.
vitamin B complex. A group of closely in-
VM&P naphtha. See naphtha (la).
terrelated vitamins found in rice bran, yeast, wheat
germ, etc., originally thought to be one substance.
VOC. See volatile organic compound.
Studies carried out by R. J. Williams and associates
later revealed the astonishing complexity of this
voids. Empty spaces of molecular dimensions oc-
group. He states as follows: “The physiological ac-
curring between closely packed solid particles, as in
tivity originally observed was due to the additive
powder metallurgy. Their presence permits barriers
effect of a considerable number of substances, each
made by powder metallurgy techniques to act as
one of which is of itself essential. If and when the
diffusion membranes for separation of uranium iso-
designations B
1
,B
2
,B
3
, etc., are used, they have an
topes in the gaseous diffusion process.
entirely different meaning from the parallel use of
See diffusion, gaseous.
D
1
,D
2
,D
3
or K
1
and K
2
because in the case of the D
and K vitamins one form can replace another. In the
Voight amination. Amination of benzoins with
case of the B vitamins each form is a distinctly
amines in the presence of phosphorus pentoxide or
different substance with different functions, and
hydrochloric acid.
each member of the family is separately indispens-
able. No one B vitamin can replace any other.”
“Volan” [Du Pont]. (methacrylatochromic
chloride). TM for bonding agent.
vitamin B
6
tripalmitate. See pyridoxine
Use: Applied to glass fibers used in reinforced plastic
tripalmitate.
laminates to improve adhesion between glass and
resin.
vitamin E acetate. See d
--tocopheryl ace-
tate.
volatile organic compound. (VOC). Any
hydrocarbon, except methane and ethane, with va-
vitexin. See 8--d-glucopyranosyl-apigenin.
por pressure equal to or greater than 0.1 mm Hg.
“Viton” [Du Pont]. TM for a series of fluoroe-
volatility. The tendency of a solid or liquid mate-
lastomers based on the copolymer of vinylidene
rial to pass into the vapor state at a given tempera-
fluoride and hexafluoropropylene with the repeating
ture. Specifically the vapor pressure of a component
structure possibly CF
2
CH
2
CF
2
CF(CF
3
).
divided by its mole fraction in the liquid or solid.
Properties: White transparent solid. D 1.72–1.86.
Resistant to corrosive liquids and chemicals up to
Volhard-Erdmann cyclization. Synthesis of
315C. Useful continuous service at 204–232C. Re-
alkyl and aryl thiophenes by cyclization of disodium
sistant to ozone, weather, flame, oils, fuels, lubri-
succinate or other 1,4-difunctional compounds (-
cants, many solvents; radiation resistance good.
oxo acids, 1,4-diketones, chloroacetyl-substituted
Nonflammable.
esters) with phosphorus heptasulfide.
Use: Gaskets, seals, diaphragms, tubing, aerospace
and automotive components, high-vacuum equip-
Volhard’s solution. A solution of potassium
ment, low-temperature and radiation equipment.
thiocyanate.
Use: Analytical chemistry.
vitreous. Descriptive of a material having the
appearance and properties of a glass, i.e., a hard,
voltaic cell. Two conductive metals of different
amorphous, brittle structure, as in porcelain enamel.
potentials, in contact with an electrolyte, which gen-
See vitrification; glass.
erate an electric current. The original voltaic cell
was composed of silver and zinc, with brine-mois-
vitreous enamel. See porcelain enamel.
tened paper as electrolyte. Semisolid pastes are now
used; electrodes may be lead, nickel, zinc, or cadmi-
vitrification. The process of converting a sili-
um.
ceous material into an amorphous, glassy form by
See solar cell.
melting and cooling. As applied to radioactive waste
disposal, it refers to incorporation of the waste in
volumetric analysis. See titration.
glassy materials for permanent storage.
Von Baeyer, Adolf. (1835–1917). A German
vitriol. An obsolete term once used to refer to a chemist who received the Nobel Prize for chemistry
number of sulfates (lead, copper, zinc) because of in 1905. His work concerned organic dyes and hy-
1323 “VYCOR” BRAND
droaromatic compounds. He was educated in Berlin Inorganic accelerators and metallic oxides (usually
zinc) are essential for satisfactory cure. Organic
under the direction of Bunsen and Kekule. He was a
accelerators, introduced in the early 1920s, notably
professor in Strasbourg and Munich. Von Baeyer
shortened vulcanization time.
made many discoveries, including barbituric acid
Three factors affect the properties of a vulcanizate:
and the molecular structure of indigo.
(1) the percentage of sulfur and accelerator used, (2)
the temperature, and (3) the time of cure. Sulfur is
Von Braun reaction. The reaction between
usually from 1 to 3%; with strong acceleration the
phosphorous pentahalide and an N-substituted benz-
time can be as short as three minutes at high temper-
amide to give an alkylene dihalide and benzonitrile.
ature (150C). Vulcanization can also occur at room
temperature with specific formulations (self-curing
von Richter reaction. Carboxylation of sub-
cements).
stituted aromatic nitro compounds with ethanolic
Vulcanization was discovered in 1846 by Charles
potassium cyanide at 120-270C, the carboxyl group
Goodyear in the U.S. and simultaneously by
entering a position ortho to that previously occupied
Thomas Hancock in England. Its overall effect is to
by the eliminated nitro group.
convert rubber hydrocarbon from a soft, tacky, ther-
moplastic to a strong, temperature-stable thermoset
von Richter synthesis. Formation of cinno-
having unique elastic modulus and yield properties.
line derivatives by diazotization of o-aminoarylpro-
See rubber; rubber, synthetic.
piolic acids or o-aminoarylacetylenes followed by
hydration and cyclization. The method is applicable
to preparation of cinnolines substituted in the benze-
“Vulcosal” [Dow]. TM for the industrial grade
noid ring.
of salicylic acid.
Use: Stabilizer and retarder of vulcanization.
“Voranate” [Dow]. TM for a series of urethane
intermediates that are the reaction products of poly-
“Vulklor” [Uniroyal]. TM for tetrachloro-p-
ols and isocyanates. They are adducts or quasiprepo-
benzoquinone.
lymers to be used in combination with “Voranol”
Use: Vulcanizing agent.
products to obtain rigid urethane foams.
“Vultex.” TM for a vulcanized rubber or synthet-
“Vorane” [Dow]. TM for a group of polyure-
ic rubber latex.
thane chemicals, raw materials for polyurethane
Use: Health care workers’ gloves, drug sundries,
elastomers, coatings, and foams.
dipped products, adhesives.
“Voranol” [Dow]. TM for a series of polyols
“Vybar” [Baker Petrolite]. TM for a grade of
used as intermediates in urethane elastomers, coat-
petroleum microcrystalline wax.
ings, and flexible and rigid foams.
Use: Hardening and upgrading paraffins, coatings,
polishes, adhesives, cosmetics, color dispersants,
VPC. Abbreviation for vapor-phase chromatog-
paper coatings, lubricants, floor wax, ski wax inks,
raphy.
ozone barriers for elastomers, and anticaking treat-
See gas chromatography.
ments.
“VPM” [Du Pont]. TM for a solution contain-
“Vycel P” [Crowley]. TM for a polyester mod-
ing 32.7% sodium methyldithiocarbamate used as a
ifier.
soil fumigant.
Use: Improves impact resistance.
vulcanization. A physicochemical change re-
sulting from cross-linking of the unsaturated hydro-
“Vycor” Brand Glass No. 7900 [Corning].
carbon chain of polyisoprene (rubber) with sulfur, TM for a glass made by a process in which an
usually with application of heat. The precise mecha- article fabricated by conventional methods is chemi-
nism that produces the network structure of the cally leached to remove substantially all of the in-
cross-linked molecules is still not completely gredients except silica. When fired at high tempera-
known. Sulfur is also used with unsaturated types of tures a transparent glass of high softening point and
synthetic rubbers; some types require use of perox- extremely low expansion coefficient is produced.
ides, metallic oxides, chlorinated quinones, or nitro- Properties: Softening point 1500C, temp limit in
benzenes. Natural rubber can be vulcanized with service 900C, linear coefficient of expansion per
selenium, organic peroxides, and quinone deriva- degree C
=
0.0000008, d 2.18, refr index 1.458 (a
tives but these have limited industrial use; high-en- similar glass, No. 7910, will transmit over 60%
ergy radiation curing is an important innovation. radiation at 254 millimicrons in a 2-mm section).
Vulcanization can be effected with sulfur alone in Use: Laboratory and industrial glassware, including
high percentage, but the time required is too long to beakers, crucibles, flasks, dishes, tubes, cylinders,
be economical and the properties obtained are poor. containers, flat glass rods.