1326WATERPROOFING AGENT
and rivers has been illegal since the early 1900s; in
wattle bark. (Australian bark; mimosa bark).
1973 the EPA prohibited dumping of all types of Derivation: From the Australian and South African
wastes into the ocean. Unintentional pollution re- wattles and South African acacias. Bark contains
sults from runoff containing toxic insecticidal resi- 25–35% tannin.
dues. Oil spills at sea are a continual problem and Grade: Based on tannin content.
probably will remain so. Use: Source of wattle bark extract, used in vegetable
See waste treatment; Environmental Protection tanning of leather, especially retannage of upper
Agency; environmental chemistry. leathers and production of heavy leathers.
waterproofing agent. (1) Any film-forming
wave function. In quantum mechanics, a com-
substance that coats a substrate with a water-repel-
plex function extending over the configuration
lent layer, such as paint, a rubber or plastic film, a
space of a system; its complex conjugate yields the
wax, or an asphaltic compound. These are used on a
probability density function, and other mathemati-
wide variety of surfaces, including cement, mason-
cal operations yield other physical quantities.
ry, metals, textiles, etc.
(2) Any metal salt or other chemical that impreg-
wax. A low-melting organic mixture or compound
nates textile fibers in such a way as to give an air-
of high molecular weight, solid at room temperature
permeable, water-resistant product. There are three
and generally similar in composition to fats and oils
types of these: renewable, semidurable, and durable.
except that it contains no glycerides. Some are hy-
Renewable repellents are water dispersions contain-
drocarbons, others are esters of fatty acids and alco-
ing aluminum acetate or formate, emulsifying
hols. They are classed among the lipids. Waxes are
agents and protective colloids in the continuous
thermoplastic, but since they are not high polymers,
phase, and a blend of waxes in the disperse phase.
are not considered in the family of plastics. Com-
Semidurable repellents involve precipitation of in-
mon properties are water repellency, smooth tex-
soluble metal salts on the fibers; water-soluble soaps
ture, low toxicity, freedom from objectionable odor
and waxes are usually added to the mixture, which is
and color. They are combustible and have good
especially effective on synthetic fibers. Durable re-
dielectric properties; soluble in most organic sol-
pellents coat each fiber with a protective film with-
vents; insoluble in water. The major types are as
out bonding them together or sealing the apertures.
follows:
I. Natural
water purification. (water conditioning).
1. Animal (beeswax, lanolin, shellac wax,
Any process whereby water is treated in such a way
Chinese insect wax)
as to remove or reduce undesirable impurities. The
2. Vegetable (carnauba, candelilla, bayberry,
following methods are used: (1) sedimentation, in
sugar cane)
which coarse suspended matter is allowed to settle
3. Mineral
by gravity in special tanks or reservoirs; (2) coagula-
(a) Fossil or earth waxes (ozocerite, ceresin,
tion of aggregates (called “floc”) by means of alumi-
montan)
num sulfate, ferric sulfate, or sodium aluminate (the
(b) Petroleum waxes (paraffin, microcrystal-
aggregates are formed from colloidally dispersed
line) (slack or scale wax)
impurities activated by the coagulant); (3) filtration
II. Synthetic
through a bed of fine sand, either by gravity flow or
1. Ethylenic polymers and polyol ether-esters
by pressure, to remove suspended particles; (4)
(“Carboxwax,” sorbitol)
chlorination, which is effective in sterilizing potable
2. Chlorinated naphthalenes (“Halowax”)
water, swimming pools, etc.; (5) adsorption on acti-
3. Hydrocarbon type, i.e., Fischer-Tropsch
vated carbon for removal of organic contaminants
synthesis
causing unpleasant taste and odor; (6) hardness re-
moval by ion-exchange or zeolite process.
Use: Polishes, candles, crayons, sealants, sun-crack-
The USDA has reported that mercury can be re-
ing protection of rubber and plastic products, abher-
moved from water by treatment with low concentra-
ent, cosmetics, paper coating, packaging food prod-
tions of black liquor from kraft papermaking.
ucts, electrical insulation, waterproofing and
cleaning compounds, carbon paper, precision in-
water-soluble gum. See gum, natural.
vestment casting.
water-soluble oil. Ammonia, potash, or sodium
wax, chloronaphthalene.
soaps of oleic, rosin, or naphthenic acids dissolved
Properties: Translucent, black, light and varied col-
in mineral oils.
ors. D 1.40–1.7 (300F), mp 87.7–129.4C, bp
Use: Boring, lathe-cutting, milling, polishing lubri-
287–371C. Soluble in many organic solvent liquids
cants, dressing textile fibers, dust laying.
and oils (when heated together).
See soluble oil.
Derivation: By chlorinating naphthalene.
Hazard: Toxic by ingestion and skin contact.
water-soluble resin. See polymer, water-sol- Use: Condenser impregnation, moisture-, flame-,
uble. acid-, insect-proofing of wood, fabric, and other