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Claims  |
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I claim:
1. The process for the production of water-soluble broken-down alkali metal
cellulose polymer by the following steps:
(a) mixing 2 parts by weight of a cellulose-containing plant with 1 to 3
parts by weight of an alkali metal hydroxide;
(b) heating the mixture at 150.degree. C. to 220.degree. C. while agitating
for 5 to 60 minutes, thereby
(c) producing a water-soluble broken-down alkali metal cellulose polymer.
2. The process of claim 1 wherein the alkali metal hydroxide is selected
from the group consisting of sodium hydroxide, potassium hydroxide or
mixtures thereof.
3. The process of claim 1 wherein an additional step is taken following
step (c) of claim 1 wherein 20% to 200% by weight of water is added, based
on the weight of the alkali metal cellulose polymer, to the broken-down
alkali metal cellulose polymer, thereby producing an aqueous solution of
broken-down alkali metal cellulose polymer.
4. The product produced by the process of claim 1.
5. The process of claim 1 wherein water is added to the alkali metal
cellulose polymer, then filtered to remove any insoluble alkali metal
cellulose polymer, thereby recovering the alkali metal cellulose not
soluble in water.
6. The product produced by the process of claim 5.
7. The process of claim 1 wherein water is added to the alkali metal
cellulose polymer, then filtered to remove the insoluble alkali metal
cellulose; the alkali metal cellulose polymer is precipitated from the
water by the addition of a mineral acid or an organic acid until the pH is
5 to 7, then filtered, thereby recovering the broken-down cellulose
polymer.
8. The product produced by the process of claim 7.
9. The process for the production of broken-down cellulose foam by mixing 2
parts by weight of a cellulose-containing plant with 1 to 3 parts by
weight of an alkali metal hydroxide selected from the group consisting of
sodium hydroxide, potassium hydroxide or mixtures thereof, then heating
the mixture at 150.degree. C. to 200.degree. C. while agitating for 5 to
60 minutes, thereby producing a water-soluble broken-down alkali metal
cellulose polymer; then 1 to 5 parts by weight of an aldehyde selected
from the group consisting of formaldehyde, acetaldehyde, propionic
aldehyde, furfural, crotonaldehyde, acrolein, benzaldehyde, butyl
aldehyde, pentanals, hexanals, heptanals, octanals and mixtures thereof,
are mixed with 2 parts by weight of the broken-down alkali metal cellulose
polymer, then agitated at ambient temperature for 10 to 120 minutes,
thereby producing an aldehyde-broken-down alkali metal cellulose
copolymer, then an acid compound, selected from the group consisting of
mineral acid, organic acid, hydrogen-containing salt, and mixtures
thereof, is added until the pH is 6 to 7, thereby producing an
aldehyde-broken-down cellulose copolymer, a cellular solid product,
without the addition of a volatile blowing agent.
10. The product produced by the process of claim 9.
11. The process for the production of aminoplast-broken-down cellulose foam
by mixing 2 parts by weight of a cellulose-containing plant with 1 to 3
parts by weight of an alkali metal hydroxide selected from the group
consisting of sodium hydroxide, potassium hydroxide or mixtures thereof,
then heating the mixture at 150.degree. C. to 220.degree. C. while
agitating for 5 to 60 minutes, thereby producing a water-soluble
broken-down alkali metal cellulose polymer; then 0.5 to 5 mols of an
aldehyde per mol of the amino compound and selected from the group
consisting of aqueous solution of formaldehyde, acetaldehyde, propionic
aldehyde, furfural, crotonaldehyde, acrolein, butyl aldehyde, pentanals,
hexanals, heptanals, octanals, paraformaldehyde and mixtures thereof, 1 to
5 parts by weight of an amino compound, selected from the group consisting
of urea, thiourea, alkyl ureas, alkyl thiourea, melamine, polyamines,
aniline and mixtures thereof, and 2 parts by weight of the broken-down
alkali metal cellulose, are mixed, then agitated at a temperature between
ambient temperature and 100.degree. C. for 10 minutes to 12 hours, thereby
producing an aminoplast-broken-down cellulose resin; then an acid
compound, selected from the group consisting of a mineral acid, an organic
acid and inorganic hydrogen-containing salt, is added until the pH is 5 to
7 while agitating until said resin begins to expand, thereby producing a
cellular solid aminoplast-cellulose product, without the addition of a
volatile blowing agent.
12. The product produced by the process of claim 11.
13. The process for the production of phenoplast-broken-down cellulose foam
by mixing 2 parts by weight of a cellulose-containing plant with 1 to 3
parts by weight of an alkali metal hydroxide selected from the group
consisting of sodium hydroxide, potassium hydroxide or mixtures thereof,
then heating the mixture at 150.degree. C. to 220.degree. C. while
agitating for 5 to 60 minutes, thereby producing a water-soluble
broken-down alkali metal cellulose polymer, then 1 to 5 parts by weight of
a phenol compound, selected from the group consisting of phenol, cresol,
creosote, cresylic acid, resorcinol, Bisphenol A, cashew nut shell liquid,
2,6-dimethylphenol, p-tert-butyl-phenol and mixtures thereof, 1 to 5 mols
of an aldehyde, selected from the group consisting of aqueous solution of
formaldehyde, acetaldehyde, propionic aldehyde, furfural, crotonaldehyde,
acrolein, butyl aldehyde, paraformaldehyde, pentanals, hexanals and
mixtures thereof, and 2 parts by weight of the broken-down alkali metal
cellulose are mixed, then agitated at a temperature from ambient to
100.degree. C. for 10 minutes to 12 hours, thereby producing a
phenoplast-broken-down alkali metal cellulose resin, then an acid
compound, selected from the group consisting of a mineral acid, an organic
acid and an inorganic hydrogen-containing salt, or mixtures thereof, is
added to said resin while agitating until the pH is 5 to 7, and the
mixture begins to expand, thereby producing a cellular solid
phenoplast-broken-down cellulose product; 1 to 5 mols of the aldehyde are
added for each mol of phenol and no volatile blowing agents are added.
14. The product produced by the process of claim 13.
15. The process of claim 11 wherein additional steps are taken wherein 2
parts by weight of the broken-down alkali metal cellulose as produced in
step (c) of claim 1, and 1 to 4 parts by weight of an organic
polyisocyanate are mixed, then agitated for 10 to 60 minutes at a
temperature between 20.degree. C. to 70.degree. C., thereby producing a
polyisocyanate-broken-down cellulose prepolymer, then 10% to 100% by
weight of a curing agent, based on weight of the prepolymer, and selected
from the group consisting of water, water containing 1% to 10% by weight
of an amine catalyst, water containing 10% to 60% by weight of a
polyhydroxy compound, water containing 10% to 60% by weight of silica sol,
water containing up to 5% by weight of an emulsifying agent, water
containing 10% to 50% by weight of sodium silicate, and mixtures thereof,
is added to the prepolymer while agitating at 20.degree. C. to 80.degree.
C. for 5 to 20 minutes, thereby producing a cellular solid or solid
polyisocyanate-broken-down cellulose product.
16. The process of claim 15 wherein the organic polyisocyanate is selected
from the group consisting of tolylene-2,4-diisocyanate,
tolylene-2,6-diisocyanate and mixtures thereof, and the phosgenation
product of an anilineformaldehyde condensation.
17. The product produced by the process of claim 16.
18. The process of claim 1 wherein additional steps are taken wherein 1 to
3 parts by weight of the broken-down alkali metal cellulose, 1 to 3 parts
by weight of a polyol, and 1 to 3 parts by weight of an organic
polyisocyanate are mixed and the resultant mixture is allowed to react,
thereby producing a polyurethane-broken-down cellulose cellular solid
product.
19. The product produced by the process of claim 18.
20. The process of claim 18 wherein the organic polyisocyanate is selected
from the group consisting of tolylene-2,4-diisocyanate;
tolylene-2,6-diisocyanate and mixtures thereof and the phosgenation
product of aniline-formaldehyde condensation product.
21. The process of claim 1 wherein 1 to 4 parts by weight of the
broken-down alkali metal cellulose and 3 parts by weight of an
isocyanate-terminated polyurethane prepolymer are mixed and the resultant
mixture is allowed to react, thereby producing a polyurethane-broken-down
cellulose cellular solid or solid product.
22. The process of claim 21 wherein the isocyanate-terminated polyurethane
prepolymer is selected from the group consisting of an
isocyanate-terminated polyester, isocyanate-terminated polyether,
isocyanate-terminated polybutadiene, isocyanate-terminated polysulfide and
mixtures thereof.
23. The product produced by the process of claim 21.
24. The process of claim 1 wherein additional steps are taken wherein 1
part by weight of the broken-down alkali metal cellulose polymer, as
produced in step (c) of claim 1, is added to water to produce an aqueous
solution containing 20% to 60% solids, then mixed with 1 to 10 parts by
weight of an organic polyisocyanate or polyisothiocyanate, and the
resultant mixture is allowed to react, thereby producing a
polyisosyanate-broken-down cellulose cellular solid or solid product.
25. The process of claim 24 wherein the polyisocyanate is selected from
tolylene-2,4-diisocyanate, tolylene-2,6-diisocyanate and mixtures thereof,
and polyphenyl-polymethylene-isocyanates.
26. The product produced by the process of claim 24.
27. The process of claim 1 wherein additional steps are taken wherein 10
parts by weight of an aqueous solution containing 20% to 60% by weight of
the broken-down alkali metal cellulose polymer, as produced in step (c) of
claim 1, are mixed with 10 to 100 parts by weight of an
isocyanate-terminated polyurethane prepolymer and 0.001 to 0.01 part by
weight of an amine catalyst and the resultant mixture is allowed to react,
thereby producing a polyurethane-broken-down cellulose cellular solid or
solid product.
28. The process of claim 27 wherein the isocyanate-terminated polyurethane
prepolymer is selected from the group consisting of an
isocyanate-terminated polyester, isocyanate-terminated polyether,
isocyanate-terminated polybutadiene, isocyanate-terminated polysulfide and
mixtures thereof.
29. The product produced by the process of claim 27.
30. The process of claim 1 wherein additional steps are taken wherein 1 to
3 parts by weight of the broken-down alkali metal cellulose polymer, as
produced in step (c) of claim 1, 1 to 3 parts by weight of an oxidated
silicon compound, selected from the group consisting of silica, alkali
metal silicates, alkaline earth metal silicates, natural silicates
containing free silicic groups and mixtures thereof, 1 to 3 parts by
weight of a polyol and 3 parts by weight of an organic polyisocyanate or
polyisothiocyanate are mixed, allowing the resultant mixture to react,
thereby producing a polyurethane-silicate-broken-down cellulose cellular
solid or solid product.
31. The process of claim 30 wherein the polyisocyanate is selected from the
groups consisting of tolylene-2,4-diisocyanate, tolylene-2,6-diisocyanate
and mixtures thereof, polyphenyl-polymethylene-isocyanate and mixtures
thereof.
32. The product produced by the process of claim 30.
33. The process for the production of a foamed broken-down cellulose
polymers which has lost a CO.sub.2 radical per each basic polymer unit by
mixing 2 parts by weight of a cellulose-containing plant with 1 to 3 parts
by weight of an alkali metal hydroxide selected from the group consisting
of sodium hydroxide, potassium hydroxide or mixtures thereof, then heating
the mixture at 150.degree. C. to 220.degree. C. while agitating for 5 to
60 minutes, thereby producing a water-soluble broken-down alkali metal
cellulose polymer, then an acid compound, selected from the group
consisting of mineral acids, organic acids, inorganic hydrogen-containing
salts and mixtures thereof, is added to the broken-down alkali metal
cellulose until the pH is 5 to 7 and the mixture expands, thereby
producing a cellular solid broken-down cellulose product, without the
addition of a volatile blowing agent.
34. The product produced by the process of claim 33.
35. The process for the production of foamed broken-down lignin-cellulose
polymer which has lost a CO.sub.2 radical per each basic cellulose polymer
unit by mixing 2 parts by weight of a plant containing lignin and
cellulose with 1 to 3 parts by weight of an alkali metal hydroxide
selected from the group consisting of sodium hydroxide, potassium
hydroxide or mixtures thereof, then heating the mixture at 150.degree. C.
to 220.degree. C. while agitating for 5 to 60 minutes, thereby producing a
water-soluble broken-down alkali metal lignin-cellulose polymer which has
lost a CO.sub.2 radical per each basic cellulose polymer unit, then an
acid compound, consisting of mineral acids, organic acids, inorganic
hydrogen-containing salts and mixtures thereof, is added to the
broken-down alkali metal lignin-cellulose polymer until the pH is 5 to 7
and the mixture expands, thereby producing broken-down lignin-cellulose
foam, without the addition of a volatile blowing agent. |
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Claims |
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Description |
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BACKGROUND OF THE INVENTION
This invention relates to a novel and economical process to break down
particles of cellulose-containing plants into smaller polymers and
compounds which are highly reactive chemically and are soluble in water
and/or common organic solvents.
The process in this invention differs from the process commonly known in
the arts to produce alkali metal cellulose by heating the cellulose in a
concentrated aqueous solution of the alkali metal hydroxide to break down
the cellulose polymers; the alkali metal cellulose produced is not soluble
in water and must be reacted with carbon disulfide before it is water
soluble. In the process of this invention, aqueous solutions are not used
and a much higher temperature is necessary to break down the cellulose
polymers in plants in order for it to be water soluble. It is not
necessary to remove the lignin for wood in the process of this invention.
When an organic or inorganic acid is added to the broken-down alkali metal
cellulose polymer, carbon dioxide is given off. The dark brown alkali
metal cellulose polymer is usually converted to a cream color after the
cellulose is reacted with other organic reactants, especially in an acetic
medium.
When wood is used as the cellulose-containing plant, the usual
lignin-cellulose bond is not broken in most of the cases, but the
molecules of cellulose are broken down into smaller molecules which are
water soluble and highly reactive chemically, especially with aldehydes,
furan compounds, polyisocyanate compounds and polyurethane prepolymers.
The broken-down polymers of cellulose-containing plants are commercially
useful polymers. The alkali cellulose of cellulose-containing plants is
highly reactive. It will produce useful resins by reacting with aldehydes,
ketones, isocyanates, vinyl acetate acrylic acid monomers, polyfunctional
alkylating agents, monofunctional alkylating agents, aldehydes and
phenols, aldehydes and amino compounds, vinyl acetate with other vinyl
monomers, acrylic acid compounds with other vinyl monomers, epihalohydrins
with polyamines, oxidated silicon compounds, sulfur, silicon halides,
organic polyhalides and polyamines, furfuryl alcohol, compounds which
contain halogen atoms capable of being quaternized or R--SO.sub.2
--groups, epoxide compounds and mixtures thereof.
The aqueous solution of the alkali metal cellulose polymers of
cellulose-containing plants may be used commercially to react with
polyisocyanate and isocyanate-terminated polyurethane prepolymers and
isocyanate-terminated polyurethane silicate prepolymers. They may be
polymerized with organic aldehydes, furfuryl alcohol, epihalohydrins and
polyamine organic polyhalide compounds, organic epichlorohydrin compounds
and a polyamine halohydrins, ketones, organic epoxides, acrylic compounds,
vinyl acetate, organic halides, organic polyhalides, organic acid
sulfates, organic poly(acid sulfates), organic nitrates, organic
polynitrates, organic acid phosphates, organic poly(acid phosphates),
organic bicarbonate, organic poly(bicarbonate) compounds containing
radicals, organic compounds containing formate radicals, organic compounds
containing poly(formate) radicals, organic compounds containing acetate,
propionate, laurate, oleate, stearate, oxalate, acid malonate, acid
tartrate, acid citrate radical and mixtures thereof.
The water-soluble broken-down alkali metal cellulose polymer may be
precipitated by the addition of a salt-forming compound, such as an
organic or inorganic acid. The water is filtered off. The water contains
5% to 30% by weight of plant polymers and, in the case of wood, some
lignin is present. The degraded cellulose polymers are precipitated as
dark brown to black fine particles which are soluble in acetic acid,
alcohols, dilute alkali hydroxide solutions and other organic solvents.
The broken-down cellulose polymers may be chemically reacted with
isocyanate compounds, polyisocyanate compounds, polythioisocyanate
compounds, silicon halides, polycarboxyl acids and their corresponding
anhydride, epoxides, aldehydes, ketones, furfuryl alcohol, epihalohydrins
and mixtures thereof.
The water-soluble broken-down cellulose polymers and lignin are soluble in
acetic and basic aqueous solutions. They may be used in the aqueous
solution to produce resins by reacting with furfural, furfuryl alcohol,
aldehyde and an amino compound, aldehyde and a phenol compound, aldehydes,
ketones, epoxides and polyamines, polyhalide organic compounds and
polyamines, isocyanates and mixtures thereof. The salt may be removed by
washing the resins with water and filtering. The water-soluble broken-down
cellulose polymers may be recovered by evaporating the water, then
extracting the polymers from the salt by using an organic solvent, and
then evaporating the organic solvent. The tan-colored cellulose polymer
may be used in the production of polyurethane resins and foams,
phenoplast, aminoplasts, aldehyde cellulose resins, ketone cellulose
resins, furfuryl alcohol-cellulose resins, cellulose silicone polymers and
as a filler in paints, varnishes, organic resins, etc.
When desirable, a higher percentage of alkali metal cellulose polymers may
be produced, which are not water soluble, be regulating the temperature
and the length of time the alkali metal hydroxide and cellulose-containing
plants are heated. These polymers are highly reactive, as previously
discussed.
Any suitable cellulose-containing plant or the products of
cellulose-containing plants which contain cellulose may be used in this
invention. The plant material is preferred to be in the form of small
particles such as sawdust. In nature, cellulose is widely distributed. It
is found in all plants and they may be used in this process, preferably in
a dry, small-particle form.
Suitable cellulose-containing plants include, but are not limited to,
trees, e.g., spruce, pine, hemlock, fir, oak, ash, larch, birch, aspen,
poplar, cedar, beech, maple, walnut, cypress, redwood, cherry, elm,
chestnut, hickory, locust, sycamore, tulip, tupelo, butternut, apple,
alder, magnolia, dogwood, catalpa, boxwood, crabwood, mahogany,
greenheart, lancewood, letterwood, mora, prima vera, purpleheart,
rosewood, teak, satinwood, mangrove, wattle, orange, lemon, logwood,
fustic, osage orange, sappanwood, Brazilwood, barwood, camwood,
sandalwood, rubber, gutta, mesquite, and shrubs, e.g., oleander, cypress,
junipers, acanthus, pyracantha, ligustrum, lantana, bougainvillea, azalea,
feijoa, ilex, fuscia, hibiscus, datura, holly, hydrangea, jasmine,
eucalyptus, cottoneaster, xylosma, rhododendron, castor bean, eugenia,
euonymus, fatshedera, aralia, etc., and agricultural plants, e.g., cotton,
cotton stalks, corn stalks, corn cobs, wheat straw, oat straw, rice straw,
cane sugar (bagasse), soybean stalks, peanut plants, pea vines, sugar beet
waste, sorghum stalks, tobacco stalks, maize stalks, barley straw,
buckwheat straw, quinoa stalks, cassava, potato plants, legume vines and
stalks, vegetable inedible portion, etc., weeds, grasses, vines, kelp,
flowers and algae. Wood fibers and cotton fibers are the preferred
cellulose-containing materials. The waste products of agricultural plants
which contain cellulose may be air-dried, then ground into small particles
and used in this invention. Commercial waste products containing
cellulose, e.g., paper, cotton cloths, bagasse wallboard, wood products,
etc., may be used in this invention. Wood with the lignin removed (wood
pulp) may be used in this invention.
Cellulose-containing plants which have been partially decomposed, such as
humus, peat and certain soft brown coal, may be used in this invention.
Other products of cellulose-containing plants may be recovered in the
process of this invention such as waxes, gums, oils, sugars, wood alcohol,
agar, rosin, turpentine, resins, rubber latex, dyes, etc.
Any suitable aldehyde may be used in this invention, such as formaldehyde,
acetaldehyde, butyl aldehyde, chloral, acrolein, furfural, benzaldehyde,
crotonaldehyde, propionaldehyde, pentanals, hexanals, heptanals, octanals
and their simple substitution products, semi-acetals and full acetals,
paraformaldehyde and mixtures thereof. Compounds containing active
aldehyde groups such as hexamethylene tetramine may also be used.
Any suitable amino compound may be used in this invention such as urea,
thiourea, alkyl-substituted thiourea, alkyl-substituted ureas, melamine,
aniline, quanidine, saccharin, dicyandiamide, benzene sulfonamides,
toluene sulfonamide, aliphatic and aromatic polyamines and mixtures
thereof. Urea is the preferred amino compound, and formaldehyde is the
preferred aldehyde when used with an amino compound.
Any suitable phenol compound may be used in this invention such as phenol,
p-cresol, o-cresol, m-cresol, cresylic acid, xylenols, resorcinol, cashew
nut shell liquids, anacordol, p-tert-butyl phenol, Bisphenol A, creosote
oil, 2,6-dimethylphenol and mixtures thereof. Phenol is the preferred
phenol compound and formaldehyde is the preferred aldehyde when used with
a phenol compound.
Any suitable mixture of the amino compounds and phenol compounds with an
aldehyde may be used in this invention.
Any suitable acid compound, inorganic or organic, may be used for salt
formation, including those which also have a chainbuilding function such
as sulphurous acid, sulphuric acid, hypophosphorous acid, phosphinic
acids, phosphonous acids and phosphonic acid, glycolic acid, lactic acid,
succinic acid, tartaric acid, oxalic acid, phthalic acid, trimellitic acid
and the like. Further examples of acids may be found in German Pat. No.
1,178,586 and in U.S. Pat. No. 3,480,592. Acids such as hydrochloric,
fluoroboric acid, amidosulphonic acid, phosphoric acid and its
derivatives, acetic acid, propionic acid, etc., may be used. Inorganic
hydrogen-containing salts may be used such as sodium hydrogen sulphate,
potassium hydrogen sulphate, sodium dihydrogen phosphate, potassium
dihydrogen phosphate and mixtures thereof.
The acid compounds may be used to react with the alkali metal atoms in the
alkali metal cellulose polymer to produce a salt and also release CO.sub.2
which expands the cellulose polymer into a cellular solid product. The
acid compounds may also be used as a catalyst in the reactions to produce
foamed aminoplast-cellulose products, foamed phenoplast-cellulose products
and aminoplast-cellulose-phenoplast foamed products. These acid compounds
may also be used in the production of polyurethane-cellulose cellular
solid products to react with the alkali metal atoms to form a salt. The
acid compounds may be used to precipitate the alkali metal cellulose from
an aqueous solution.
Any suitable oxidated silicon compound may be used in this invention such
as silica, e.g., hydrated silica, silicoformic acid, silica sol, etc.,
alkali metal silicates, alkaline earth metal silicates, natural silicates
with free silicic acid groups and mixtures thereof. The hydrated silica
includes various silicon acids such as silicic acid gel, orthosilicic
acid, metasilicic acid, monosilandiol, polysilicoformic acid, etc.
Hydrated silica is the preferred oxidated silicon compound.
Any suitable organic polyisocyanate may be used according to the invention,
including aliphatic, cycloaliphatic, araliphatic, aromatic and
heterocyclic polyisocyanates. Suitable polyisocyanates are, for example,
arylene polyisocyanates such as tolylene, metaphenylene;
4-chlorophenylene-1,3-; methylene-bis-(phenylene-4-); biphenylene-4,4'-;
3,3-dimethoxy-biphenylene-4,4'-; 3,3'-diphenylbiphenylene-4,4'-;
naphthalene-1,5- and tetrahydronaphthalene-1,5-diisocyanates and
triphenylmethane triisocyanate; alkylene polyisocyanates such as ethylene,
ethylidene; propylene-1,2-; butylene-1,4-; butylene-1,3-; hexylene-1,6-;
decamethylene-1,10-; cyclohexylene-1,2-; cyclohexylene-1,4-; and
methylene-bis-(cyclohexyl-4,4'-) diisocyanates.
It is generally preferred to use commercially readily available
polyisocyanates, e.g., tolylene-2,4- and -2,6-diisocyanate and any
mixtures of these isomers, ("TDI"), polyphenylpolymethylene-isocyanates
obtained by aniline-formaldehyde condensation followed by phosgenation
("crude MDI"), and polyisocyanates which contain carbodiimide groups,
urethane groups, allophanate groups, isocyanurate groups, urea groups,
imide groups or biuret groups, ("modified polyisocyanates"). Inorganic
polyisocyanates are also suitable according to the invention. Suitable
polyisocyanates which may be used according to the invention are
described, e.g., by W. Siefken in Justus Liebigs Annalen der Chemie, 562,
pages 75 to 136.
Solutions of distillation residues accumulating during the production of
tolylene diisocyanate, diphenyl methane diisocyanate or hexamethylene
diisocyanate, in monomeric polyisocyanates or in organic solvents and
mixtures thereof may be used in this process. Phosgenation products of
condensates of aniline or anilines alkylsubstituted on the nucleus, with
aldehydes or ketones, may be used in this invention.
Organic polyhydroxyl compounds (polyols) may be used in this invention with
polyisocyanates or may be first reacted with a polyisocyanate to produce
isocyanate-terminated polyurethane prepolymers and then also used in this
invention.
Reaction products of from 50 to 99 mols of aromatic diisocyanates with from
1 to 50 mols of conventional organic compounds with a molecular weight of,
generally, from about 400 to about 10,000, which contain at least two
hydrogen atoms capable of reacting with isocyanates, may also be used.
While compounds which contain amino groups, thiol groups or carboxyl
groups may be used, it is preferred to use organic polyhydroxyl compounds,
in particular, compounds which contain from 2 to 8 hydroxyl groups,
especially those with a molecular weight of from about 800 to about 10,000
and preferably from about 1,000 to about 6,000, e.g., polyesters,
polyethers, polythioethers, polyacetals, polycarbonates or polyester
amides containing at least 2, generally from 2 to 8, but preferably from 2
to 4, hydroxyl groups, of the kind known for producing homogeneous and
cellular polyurethanes.
The hydroxyl group containing polyesters may be, for example, reaction
products of polyhydric alcohols, preferably dihydric alcohols, with the
optional addition of trihydric alcohols, and polybasic, preferably
dibasic, carboxylic acids. Instead of the free polycarboxylic acids, the
corresponding polycarboxylic acid anhydrides or corresponding
polycarboxylic acid esters of lower alcohols or their mixtures may be used
for preparing the polyesters. The polycarboxylic acid may be aliphatic,
cycloaliphatic, aromatic and/or heterocyclic and may be substituted, e.g.,
with halogen atoms and may be unsaturated. Examples include: succinic
acid, adipic acid, sebacic acid, suberic acid, azelaic acid, phthalic
acid, phthalic acid anhydride, isophthalic acid, tetrahydrophthalic acid
anhydride, trimellitic acid, hexahydrophthalic acid anhydride,
tetrachlorophthalic acid anhydride, endomethylene tetrahydrophthalic acid
anhydride, glutaric acid anhydride, fumaric acid, maleic acid, maleic acid
anhydride, dimeric and trimeric fatty acids such as oleic acid, optionally
mixed with monomeric fatty acids, dimethylterephthalate and bis-glycol
terephthalate. Any suitable polyhydric alcohol may be used such as, for
example, ethylene glycol; propylene-1,2- and -1,3-glycol; butylene-1,4-
and -2,3-glycol; hexane-1,6-diol; octane-1,8-diol; neopentyl glycol;
cyclohexanedimethanol-(1,4-bis-hydroxymethylcyclohexane);
2-methyl-propane-1,3-diol; glycerol; trimethylol propane;
hexane-1,2,6-triol; butane-1,2,4-triol; trimethylol ethane;
pentaerythritol; quinitol; mannitol and sorbitol; methylglycoside;
diethylene glycol; triethylene glycol; tetraethylene glycol; polyethylene
glycols; dipropylene glycol; polypropylene glycols; dibutylene glycol and
polybutylene glycols. The polyesters may also contain a proportion of
carboxyl end groups. Polyesters of lactones, such as
.epsilon.-caprolactone, or hydroxycarboxylic acids such as
.omega.-hydroxycaproic acid, may also be used.
The polyethers with at least 2, generally from 2 to 8 and preferably 2 or
3, hydroxyl groups used according to the invention are known and may be
prepared, e.g., by the polymerization of epoxides, e.g., ethylene oxide,
propylene oxide, butylene oxide, tetrahydrofuran, styrene oxide or
epichlorohydrin, each with itself, e.g., in the presence of BF.sub.3, or
by addition of these epoxides, optionally as mixtures or successively, to
starting components which contain reactive hydrogen atoms such as alcohols
or amines, e.g., water, ethylene glycol; propylene-1,3 or 1-2-glycol;
trimethylolpropane; 4,4-dihydroxydiphenylpropane, aniline, ammonia,
ethanolamine or ethylenediamine. Sucrose polyesters such as those
described, e.g., in German Auslegeschriften Nos. 1,176,358 and 1,064,938,
may also be used according to the invention. It is frequently preferred to
use polyethers which contain predominantly primary OH groups, (up to 90%
by weight, based on the total OH groups contained in the polyether).
Polyethers modified with vinyl polymers such as those which may be
obtained by polymerizing styrene or acrylonitrile in the presence of
polyethers, (U.S. Pat. Nos. 3,383,351; 3,304,273; 3,523,093 and 3,110,695;
and German Patent No. 1,152,536) and polybutadienes which contain OH
groups are also suitable.
By "polythioethers" are meant, in particular, the condensation products of
thiodiglycol with itself and/or with other glycols, dicarboxylic acids,
formaldehyde, aminoc | | |
