Process for the production of polyisocyanate lignin-cellulose plastics

I claim:

1. A process for producing polyisocyanate lignin-cellulose plastics by the following steps:

(a) mixing Component B, an organic polyisocyanate, or polyisothiocyanate with Component A, a broken-down alkali metal lignin-cellulose polymer;

(b) agitating the mixture at between 20.degree. C. and 60.degree. C. for 10 to 30 minutes, thereby producing a polyisocyanate alkali metal lignin-cellulose prepolymer;

(c) admixing Component C, an organic additive, and, Component D, a curing agent, with the polyisocyanate alkyl metal lignin-cellulose prepolymer and allowing the resultant mixture to react, wherein said organic additive contains 1 to 9 carbon atoms, has a molecular weight of from 32 to 400 and is selected from the group consisting of monoalcohols, monothioalcohols, monophenols, monothiophenols, halomethyl group containing compounds, esters, ethers, thioethers, ketones, nitro-group-containing compounds, monocarboxylic acid chlorides, monocarboxylic acid bromides, monosulphonic acids or salts thereof, monocarboxylic acid or salts thereof, and aldehydes, with the proviso that when said organic additive is a monoalcohol, monothioalcohol, monophenol, monothiophenol or monocarboxylic acid, said mixing of Components C and D into the polyisocyanate silicate prepolymer takes place substantially simultaneously.

2. The process of claim 1 wherein Component C is a compound or radical containing a functional group corresponding to one of the following general formulae: ROH, RSH, RCH.sub.2 Cl, RCH.sub.2 I, RCN, RNO.sub.2, RCOCl, RCOBr, RSO.sub.2 Cl, RCOOH, RSO.sub.3 H, ROR, RCOOR or ##STR2## wherein R is CH.sub.3.sup.-, C.sub.2 H.sub.5.sup.- or C.sub.2 H.sub.7.sup.-.

3. The process of claim 1, wherein said organic additive is selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, isobutanol, t-butyl alcohol and the isomeric pentanols, hexanols and heptanols, cyclohexanol, methylcyclohexanol, methallyl alcohol, allyl alcohol, cyclohexano-methanol, benzyl alcohol, butylmercaptan, phenol, cresols, thiophenol and thiocresols; formaldehyde, acetaldehyde, propionaldehyde, butyl aldehyde, pentanols, hexanals, heptanals, octanals, and the corresponding semi-acetals and full acetals; formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, pentanoic acid, hexane carboxylic acid, heptane carboxylic acid, cyclohexane carboxylic acid, benzoic acid, toluic acid; acetyl chloride, propionic acid chloride, acetyl bromide, acid chloride of C.sub.4 -C.sub.6 monocarboxylic acids, methane sulphonic acid chloride, benzenesulphonic acid chloride, p-toluene sulphochloride, o-toluene sulphochloride, carbamic acid chlorides, phenylcarbamic chloride; methyl acetate, ethyl acetate, propyl acetate, butyl acetate, amyl acetate, the methyl and ethyl esters of propionic, butyric, pentanoic, hexanoic and heptanoic and the corresponding isomeric compounds; cyclohexyl methyl ether, methyl butyl ether, phenol methyl ether, thiophenol methyl ether, cresol methyl ether, tetrahydrofuranomethylmethyl ether; ethyl chloride, ethyl bromide, ethyl iodide, n-propyl chloride, n-propyl bromide, n-propyl iodide, isopropyl chloride, isopropyl bromide, isopropyl iodide, butyl chloride, butyl bromide, butyl iodide, benzyl halides, hexahydrobenzyl halides, cyclohexanomethyl chloride, epichlorohydrin, 2-ethyl-2-chloromethyloxetane; methyl ethyl ketone, methyl-isopropyl ketone, methyl-isobutyl ketone, methyl-isoamyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, methyl-t-butyl ketone, methyl-furanyl ketone, methyl-tetrahydro-furanyl ketone, methyl-heptyl ketone, ethylhexyl ketone, acetophenone, .omega.-chloroacetophenone and propiophenone; acetonitrile, propionitrile, butyronitrile, tolunitrile, hexahydrobenzonitrile, acrylonitrile, allylnitrile, methallylnitrile and methacrylonitrile; nitromethane, nitroethane, nitrohexane, nitrobenzene, chlorinated nitrobenzenes, nitrocyclohexanes, brominated nitrobenzenes, benzyl nitrate and nitrotoluene; methanesulphonic acid, ethanesulphonic acid, butanesulphonic acid, benzenesulphonic acid, 2-toluenesulphonic acid, 4-toluenesulphonic acid, chlorosulphonic acid esters and sulphonic acid esters; trimethylphosphite, trimethylphosphate, triethylphosphite and triethylphosphate; calcium lignosulfonate, lignosulfonic acid sodium salts, and lignin sulfate produced by alkali process and mixtures thereof.

4. The process of claim 1 wherein methanol is the organic additive of Component C.

5. The process of claim 1 wherein the components are added in the following ratio:

(a) 2 parts by weight of Component A to from 1 to 10 parts by weight of Component B;

(b) 1% to 30% by weight of Component C, based on weight of Component B;

(c) 1 to 80 parts by weight of Component D to 70 to 80 parts by weight of Component B.

6. The process of claim 1 wherein the polyisocyanate compound is selected from the group consisting of 2,4-toluene diisocyanate, 2-6-toluene diisocyanate, polyphenyl-polymethyleneisocyanates obtained by aniline-formaldehyde condensation followed by phosgenation, modified polyisocyanates which contain carbon diimide groups, urethane groups, allophanate groups, isocyanurate groups, urea groups, imide groups or biuret groups and mixtures thereof.

7. The process of claim 1 wherein Component D is water.

8. The process of claim 1 wherein up to 50% by weight, based on the reaction mixture, of a chemically inert blowing agent, boiling within the range of -25.degree. C. to 80.degree. C., is added.

9. The process of claim 1, wherein the reaction is accompanied by foaming.

10. The process of claim 1, wherein the mixture contains up to 20% by weight, based on the reaction mixture, of a foam stabilizer.

11. The process of claim 1 wherein the mixture contains up to 20% by weight, based on the reaction mixture, of an emulsifying agent.

12. The process of claim 1 wherein inorganic or organic particulate or pulverulent materials are added to the reaction mixture.

13. The product of the process of claim 1.

14. The process of claim 1 wherein the Components A, B, C and D are substantially simultaneously mixed.

15. The process of claim 14.

16. The process of claim 1 wherein an additional step is taken wherein the organic polyisocyanate is reacted with a polyol to produce a liquid isocyanate-terminated polyurethane prepolymer and used as Component B, and the polyol is added in the ratio of 1 to 50 mols to 5 to 99 mols of the polyisocyanate.

17. The process of claim 1 wherein a polyol is added to Component C in the ratio of 1 to 50 mols to 50 to 99 mols of Component B.

18. A polyisocyanate lignin-cellulose plastic, having high strength, elasticity, flame resistance and dimensional stability with increase in temperature, is prepared by the process which comprises substantially simultaneously mixing and reacting an organic polyisocyanate or polyisothiocyanate, a broken-down alkali metal lignin-cellulose polymer selected from the group consisting of broken-down sodium lignin-cellulose polymer and broken-down potassium lignin-cellulose polymer, an organic additive selected from the group consisting of monoalcohols, monothioalcohols, monophenols, and monothiophenols, said organic additive having a molecular weight of up to about 400, an activator selected from the group consisting of tertiary amines and organo-tin compounds, and a curing agent selected from the group consisting of water, and water containing an alkali metal silicate, said polyisocyanate lignin-cellulose plastic being the solid product.

19. The process of claim 1 wherein the mixture contains from 0.001% to 10% by weight based on the reaction mixture of an activator selected from the group consisting of tertiary amines, organo-tin compounds and silaamines.

20. The process of claim 1 wherein the organic polyisocyanate is selected from the group consisting of arylene polyisocyanates, alkylene polyisocyanates, phosgenation products of aniline-formaldehyde condensation and mixtures thereof.

Description Submit all comments and votes

BACKGROUND OF THE INVENTION

This invention relates to a process for the production of polyisocyanate lignin-cellulose plastic utilizing a broken-down alkali metal lignin-cellulose polymer, an organic compound having at least two isocyanate groups, an organic amphiphilous compound and a curing agent and/or activator.

The products produced by this invention have many commercial uses and may be utilized as thermal-insulating material, noise-insulating material, floatation materials in boats, shock-resistant packaging, cushions, as fiber, as coating agents, as fillers, as impregnating agents, as adhesives, as casting material, as putty materials, as caulking materials, as constructional components of a building, etc. The products are novel, economical, possess improved heat- and flame-resistant properties and some have wood-like physical properties. The products may be produced by spraying or mixing in place.

In the process according to the invention, at least 3 components are used to produce the novel polyisocyanate cellulose plastics as follows:

1. Component A: A broken-down alkali metal lignin-cellulose polymer;

2. Component B: An organic polyisocyanate or polyisocyanate;

3. Component C: An amphiphilous organic compound;

4. Component D: Optionally, a curing agent and/or activator.

Component A

Component A, a broken-down alkali metal lignin-cellulose polymer, is produced by the processes outlined in my copending U.S. Patent Application, Ser. No. 013,139, filed Feb. 21, 1979, and is incorporated into this invention.

Broken-down alkali metal lignin-cellulose polymers are produced by mixing 3 parts by weight of a cellulose-containing plant or plant derivative and 2 to 5 parts by weight of an alkali metal hydroxide, then heating the mixture at 150.degree. C. to 220.degree. C. while agitating for 5 to 60 minutes.

Any suitable plant or the products of plants which contain cellulose may be used in this invention. The plant material is preferred to be in the form of small dry particles such as sawdust. Suitable plants include, but are not limited to, trees, bushes, agricultural plants, weeds, straw, vines, flowers, kelp, algae and mixtures thereof. Wood is the preferred plant. Commercial and agricultural waste products may be used, such as stalks, paper, cotton cloths, bagasse, etc. Plants that have been partially decomposed, such as humus, peat, certain soft brown coal, manure containing cellulose, etc., may also be used in this invention.

Any suitable alkali metal hydroxide may be used in this invention. Suitable alkali metal hydroxides include sodium hydroxide, potassium hydroxide and mixtures thereof. Sodium hydroxide is the preferred alkali metal hydroxide.

The broken-down alkali metal lignin-cellulose polymers are produced by mixing about 3 parts by weight of a cellulose-containing plant in the form of small particles and 2 to 5 parts by weight of an alkali metal hydroxide. The mixture is then heated to 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 product. The broken-down alkali metal lignin-cellulose polymer is ground into small particles or powder. Care must be taken to avoid having the mixture catch on fire. Sodium hydroxide is the preferred alkali metal hydroxide. Wood is the preferred plant.

Any unreacted plant particles may be used as a filler.

The broken-down alkali metal lignin-cellulose polymer utilized in this invention is a novel polymer and is different than any of the known alkali metal cellulose polymers. This polymer has lost a carbon dioxide per molecule of the broken-down alkali metal lignin-cellulose polymer and is water soluble. The lignin-cellulose bond appears to be intact. When an acid compound is added to an aqueous solution of the broken-down alkali metal lignin-cellulose until the pH is 5 to 6, the lignin-cellulose polymer polymerizes into a tough, brown resinous product which floats to the top while a carbohydrate portion remains in the water. Carbon dioxide gas is given off in the reaction.

Component B

Any suitable polyisocyanate or polyisothiocyanate may be used in this invention, including aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic polyisocyanates and mixtures thereof, such as, for example, arylene polyisocyanates such as tolylene; metaphenylene; 4-chlorophenylene-1,3; methylene-bis(phenylene-4); biphenylene-4,4'; 3,3'-dimethoxybiphenylene-4,4'; 3,3'-diphenylbiphenylene-4,4'; naphthalene-1,5; and tertrahydronaphthalene-1,5-diisocyanate and triphenylmethane triisocyanate; alkylene polyisocyanates such as ethylene; ethylidine; propylene-1,2; butylene-1,4; 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. Phosgenation products of aniline-formaldehyde condensation may be used, such as polyphenyl-polymethylene polyisocyanates. Polyisothiocyanates, inorganic polyisothiocyanates, polyisocyanates which contain carbodiimide groups as described in German Pat. No. 1,092,007 and polyisocyanates which contain urethane groups, allophanate groups, isocyanurate groups, urea groups, imide groups or biuret groups may be used to produce polyisocyanate silicate prepolymers or polyisocyanate organic silicate solid or cellular solid products. Mixtures of the above-mentioned polyisocyanates may be used.

It is generally preferred to use commercial, readily available polyisocyanates such as toluene-2,4- and -2,6-diisocyanate and any mixtures of these isomers, ("TDI"), ("crude MDI"), polyphenyl-polymethylene-isocyanates obtained by aniline-formaldehyde condensation followed by phosgenation, and modified polyisocyanates which contain carbondiimide groups, urethane groups, allophanate groups, isocyanurate groups, urea groups, imide groups or biuret groups ("modified polyisocyanates") and mixtures thereof.

Other polyisocyanates may be used in this invention, such as polyisocyanates which contain ester groups such as those listed in British Pat. Nos. 956,474 and 1,086,404; in U.S. Pat. Nos. 3,281,378 and 3,567,763; polyisocyanate reaction products with acetals according to German Pat. No. 1,072,385; polyisocyanates prepared by telomerization reactions as described in Belgian Pat. No. 723,640; polyphenyl-polymethylene polyisocyanates as described in British Patent Specification Nos. 874,430 and 848,671; polyisocyanates which contain carbondiimide groups as described in German Pat. No. 1,092,007; perchlorinated arylpolyisocyanates such as those described, e.g., in German Pat. No. 1,157,601; polyisocyanates which contain allophanate groups as described, e.g., in British Pat. No. 994,890 and in Belgian Pat. No. 761,628; and the diisocyanates described in U.S. Pat. No. 3,492,330; polyisocyanates which contain biuret groups as described, e.g., in German Pat. No. 1,101,394; in British Pat. No. 889,050; and in French Pat. No. 7,017,514; polyisocyanates which contain isocyanurate groups as described, e.g., in German Pat. Nos. 1,022,789 and 1,027,394; and in British Pat. Nos. 1,091,949; 1,267,011 and 1,305,036; polyisocyanates which contain acylated urea groups according to U.S. Pat. No. 3,517,139; and polyisocyanates which contain urethane groups as described, e.g., in Belgian Pat. No. 752,261; or in U.S. Pat. No. 3,394,164. Mixtures of the above-named polyisocyanates may be used. Organic polyisocyanates which are modified with ionic groups, for example, with carboxyl and/or carboxylate groups and/or sulphonic acid groups and/or sulphonate groups may be used with the polyisocyanates in this invention. Polyisocyanates may be reacted with alkali metal silicates such as sodium metasilicate pentahydrate, potassium metasilicate pentahydrate, dry granular crude sodium silicate, and dry granular lithium silicate to produce polyisocyanate alkali metal silicate prepolymer with terminal isocyanate groups or terminal alkali metal silicate groups and may be used with the polyisocyanates in this invention. The polyisocyanate is mixed with the dry granular alkali metal silicate, then heated to 30.degree. C. to 40.degree. C. while agitating at ambient pressure for 10 to 30 minutes, thereby producing a polyisocyanate prepolymer. Any of the suitable non-ionic hydrophilically modified organic polyisocyanates may be used in this invention.

Suitable polyisocyanates such as the aromatic diisocyanates may be reacted with organic compounds which contain at least two hydrogen atoms capable of reacting with isocyanates, preferably with a molecular weight of, generally, from 300 to about 10,000 and in the ratio of from 50 to 99 mols of aromatic diisocyanates with 1 to 50 mols of said organic compounds to produce isocyanate-terminated reaction products. It is preferred to use polyols (organic polyhydroxyl compound), in particular, compounds and/or polymers 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 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 homogenous and cellular polyurethanes. Compounds which contain amide groups, thiol groups or carboxyl groups may be used. Polyhydroxyl compounds (polyols) which already contain urethane or urea groups, modified or unmodified natural polyols, e.g., castor oil, carbohydrates and starches, may also be used. Additional products of alkylene oxides with phenolformaldehyde resins of urea-formaldehyde resins are also suitable for the purpose of the invention. Polybutadiene polymers with free hydroxyl groups, polysulfide polymers, polybutadienestyrene copolymers and butadiene-acrylonitrile copolymer chains are also suitable for the purposes of the invention.

Polyesters (polyols) containing hydroxyl groups may be, for example, reaction products of polyhydric alcohols, preferably dihydric alcohols and polybasic, preferably dibasic, carboxylic acids. The corresponding polycarboxylic acid anhydride or corresponding polycarboxylic acid esters of lower alcohols or their mixture may be used instead of the free polycarboxylic acids 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, suberic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, trimellitic acid, phthalic acid anhydride, tetrahydrophthalic acid anhydride, hexahydrophthalic acid anhydride, tetrachlorophthalic acid anhydride, glutaric acid anhydride, maleic acid, maleic acid anhydride, fumaric acid, dimeric and trimeric fatty acids such as oleic acid, optionally mixed with monomeric fatty acids, dimethylterephthalate and bis-glycol terephthalate. Any suitable polyhydric alcohols (polyol) 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, cyclohexanedimethol(1,4-bis-hydroxy-methylcyclohexane), 2-methyl-propane-1,3-diol, glycerol, trimethylol propane, hexane-1,2,6-triol, butane-1,2,4-triol, trimethylol ethane, pentaerythritol, quinitol, mannitol, sorbitol, glucose, starches, fructose, cane sugar, dextrines, castor oils, methylglycoside, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycols, dipropyleneglycol, 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 to 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, propyleneoxide, butylene oxide, tetrahydrofuran, styrene oxide or epichlorohydrin, each with itself, e.g., in the presence of BF.sub.3 or by the 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, trimethylol propane, 4,4'-dihydroxydiphenylpropane, aniline, ammonia, ethanolamine or ethylenediamine. Sucrose polyethers such as those described, e.g., in German Pat. Nos. 1,176,358 and 1,064,938 may also be used according to this invention. It is frequently preferred to use polyethers which contain predominantly primary OH groups (up to 90% by weight, based on the total OH group content of the polyether). Also suitable are 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; 3,525,093 and 3,110,695; and German Pat. No. 1,152,536) and polybutadienes which contain OH groups.

"Polythioethers" mean, in particular, the condensation products of thiodiglycol with itself and/or with other glycols, dicarboxylic acids, formaldehyde, aminocarboxylic acids or amino alcohols. The products obtained are polythio-mixed ethers, polythioether esters or polythioether ester amides, depending on the cocomponent.

The polyacetals used may be, for example, the compounds which may be obtained from glycols, e.g., diethylene glycol, triethylene glycol (4,4'-dihydroxydiphenyldimethylmethane), hexanediol and formaldehyde. Polyacetals suitable for the invention may also be prepared by the polymerization of cyclic acetals.

The polycarbonates with hydroxyl groups used may be of the known kind, e.g., those which may be prepared by reacting diols, e.g., propane-1,3-diol, butane-1,4-diol and/or hexane-1,6-diol or diethylene glycol, triethylene glycol or tetraethylene glycol, with diarylcarbonates, e.g., diphenylcarbonate or phosgene.

The polyester amides and polyamides include, e.g., the predominantly linear condensates obtained from polyvalent saturated and unsaturated carboxylic acids or their anhydrides and polyvalent saturated and unsaturated amino alcohols, diamines, polyamines and mixtures thereof.

Examples of these compounds which are to be used, according to the invention, have been described, e.g., in High Polymers, Volume XVI, "Polyurethanes, Chemistry and Technology", published by Saunders-Frisch, Interscience Publishers, New York, London, Volume I, 1962, pages 32 to 42 and pages 44 to 54 and Volume II, 1964, pages 5 and 6 and pages 198 and 199; and in Kunststoff-Handbuch, Volume VII, Vieweg-Hochtlen, Carl-Hanser-Verlag, Munich, 1966, e.g., on pages 45 to 71.

Suitable modified organic polyisocyanates, as well as their prepolymers, especially those based on aromatic polyisocyanates, can also be subsequently modified to give ionic groups, for example, by reaction with sulfones, beta-lactones, and by grafting on acrylic acid, methacrylic acid or crotonic acid, for example, or by sulphuric acid, chlorosulphonic acid, oleum or sulphur trioxide and then used in the invention. In particular, organic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate and the known phosgenation products of the condensation products of aromatic monoamines, especially aniline and aldehyde, especially formaldehyde which is reacted with sulphuric acid, oleum or sulphur trioxide, may be used in this invention. Sulphonated polyisocyanates of this kind which generally still contain ureadione, urea and buret groups and, in particular, where polyol modification has been carried out before sulphonation, urethane and/or allophanate groups which are formed through secondary reactions during sulphonation are, therefore, particularly preferred as polyisocyanates containing ionic groups. The NCO-terminated prepolymers used, for example, for the production of aqueous polyurethane dispersions (U.S. Pat. No. 3,756,992) can be used for the process according to the invention.

Component C

Component C contains organic amphiphilous compounds, preferably containing from 1 to 9 carbon atoms, and has a molecular weight of from 12 to about 400, preferably from 32 to 150, which contain one OH group and/or at least one other hydrophilic and/or polar group. The other hydrophilic and/or polar group is, preferably, a functional group corresponding to one of the following general formulae: RSH, RCH.sub.2 Cl, RCH.sub.2 Br, RCH.sub.2 I, RCN, RNO.sub.2, RCOCl, RCOBr, RSO.sub.2 Cl, RCOOH, RSO.sub.3 H, RCOO.sup.-, RSO.sub.3.sup.-1, ROR, ##STR1## wherein R denotes a methyl, ethyl or propyl group. The organic amphiphilous compounds of Component C may contain an OH group and/or from to to 6, preferably 1 or 2, of these other functional groups.

The following are examples of Component C:

1. Alcohols, thioalcohols, phenols and thiophenols: Methanol, ethanol, propanol, isopropanol, butanol, isobutanol, t-butyl alcohol and the isomeric pentanols, hexanols and heptanols, cyclohexanol, methylcyclohexano-methanol, benzyl alcohol, butylmercaptan, phenols, e.g., phenol and the cresols, thiophenols and thiocresols; also alcohols with from 1 to 4 carbon atoms are preferred, particularly methanol.

2. Aldehydes: Formaldehyde, acetaldehyde, propionaldehyde, butyl aldehyde, pentanals, hexanals, heptanals, octanals, and their simple substitution products, semi-acetals and full acetals.

3. Carboxylic acids: Formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, pentanoic acid, hexane carboxylic acid, heptane carboxylic acid, cyclohexane carboxylic acid, benzoic acid, toluic acid.

4. Carboxylic acid chlorides, carboxylic acid bromides, sulphonic chlorides: Acetyl chloride, propionic acid chloride, acetyl bromide, acid chlorides of C.sub.4 -C.sub.6 monocarboxylic acids, but also methanesulphonic acid chloride, benzenesulphonic acid chloride, p-toluenesulphochloride, o-toluenesulphochloride, carbamic acid chlorides, e.g., t-butyl carbamic chloride, and phenulcarbamic chloride.

5. Esters: Methyl acetate, ethyl acetate, propylacetate, butyl acetate, amyl acetate, the methyl and ethyl esters of propionic, butyric, pentanoic, hexanoic and heptanoic acid and the corresponding isomeric compounds, for example, isobutyric acid and 2,4,6-tribromophenylacetate.

6. Ethers and thioethers: Methyl ethyl ether, cyclohexyl methyl ether, methyl butyl ether, phenol methyl ethyl, thiophenol methyl ether, cresol methyl ether, tetrahydrofuranomethyl-methyl ether.

7. Halomethyl compounds: Ethyl chloride, ethyl bromide, ethyl iodide, n-propylchloride, n-propylbromide, n-propyliodide, isopropyl chloride, isopropyl bromide, isopropyl iodide, butyl chloride, butyl bromide, butyl iodide, C.sub.3 -C.sub.6 -halogenated methyl compounds, benzylhalides, e.g., benzylchloride or benxylbromide, hexahydrobenzyl halides, e.g., cyclohexanomethyl chloride, epichlorohydrin, 2-ethyl-2-chloromethyloxetane and 2-ethyl-2-chloro-methyloxetane. Halogenated methyl compounds which contain from 4 to 7 carbon atoms are preferred.

8. Ketones: Methyl ethyl ketone, methyl-isopropyl ketone, methylisobutyl ketone, methyl-isoamil ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, methyl-t-butyl ketone, methyl-furanyl ketone, methyl-tetrahydrofuranyl ketone, methyl-heptyl ketone, ethylhexyl ketone, acetophenone, .omega.-chloroacetophenone and propiophenone.

9. Nitriles: Acetonitrile, propionitrile, butyronitrile, tolunitrile, hexahydrobenzonitrile, acrylonitrile, allylnitrile, methallylnitrile, methacrylonitrile.

10. Nitro compounds: Nitromethane, nitroethane, nitrohexane, nitrobenzene, chlorinated nitrobenzenes, nitro-cycohexanes, brominated nitrobenzenes, benzyl nitrate and nitrotoluene.

11. Sulphonic acids: Methanesulphonic acid, ethanesulphonic acid, butanesulphonic acid, benzenesulphonic acid, 2-toluenesulphonic acid, 4-toluenesulphonic acid, chlorosulphonic esters and sulphonic acid esters, e.g., methanesulphonic acid methyl ester, methane sulphonic acid ethyl ester and chlorosulphonic acid methyl ester.

The carboxyl acids and/or sulphonic acids may be partially or completely neutralized, for example, with an alkali metal and alkaline earth metal hydroxides, e.g., sodium hydroxide, barium hydroxide or magnesium hydroxide; or by the addition of amines, e.g., trimethylamine, triethylamine, methylmorpholine, pyridine, dimethylaniline or metal alcoholates, e.g., sodium t-butanolate or potassium isopropanolate. Metal oxides, hydroxides or carbonates, either in the solid form or suspended in diluents, may also be used for neutralization. Calcium oxide, magnesium oxide, calcium carbonate, magnesium carbonate and dolomite, for example, are particularly suitable. Tertiary amines are useful in this neutralization, e.g., alkoxylated products of primary and secondary amines, and also polyesters or polyacrylates which contain tertiary nitrogen atoms as well as the known condensation products based on epichlorohydrin and polyamines.

12. Components C, according to this invention, may also comprise compounds which contain phosphorus, for example, trimethyl phosphite, trimethylphosphates, triethylphosphite, triethylphosphate, diethylphosphite, diethylphosphate, dimethylphosphite, dimethylphosphate, thiophosphoric acid-O, O-dimethylester, thiophosphoric acid trimethylester, or thiophosphoric acid-O, O-dimethylester chloride.

13. Lignin: Calcium lignosulfonate, lignosulfonic acid sodium salts, lignosulfonic acid, lignin sulfate produced by the alkali process (Kraft's process) and, particularly, desulfonated lignin.

Component D

Component D contains the curing agents and/or activators. The following are examples of Component D:

1. Water.

2. Water containing 10% to 70% by weight of an alkali metal silicate, such as sodium and/or potassium silicate. Crude commercial alkali metal silicate may contain other substances, e.g., calcium silicate, magnesium silicate, borates or aluminates may also be used. The molar ratio of Ml.sub.2 ISiO.sub.2 (Ml=metal) is not critical and may vary within the usual limits, but is, preferably, between 4 to 1 and 0.2 to 1.

3. Water containing 20% to 50% by weight of ammonium silicate.

4. Water containing 5% to 40% by weight of magnesium oxide in the form of a colloidal dispersion.

5. Alkali metal metasilicate pentahydrate such as sodium, commercial dry granular sodium, potassium silicate and potassium metasilicate pentahydrate.

6. Water containing 20% to 70% by weight of silica sol.

7. Water containing 0.001% to 10% by weight of an activator (catalyst) such as:

(a) tertiary amines, e.g., triethylamine, tributylamine, N-methyl-morpholine, N-ethyl-morpholine, N-cocomorpholine, N,N,N',N'-tetramethylethylenediamine, 1,4-diazo-bicyclo-(2,2,2)-octane, N-methyl-N'-dimethylaminoethyl, piperazine, N,N-dimethylbenzylamine, bis (N,N-diethylaminoethyl)-adipate, N,N-diethylbenzylamine, pentamethyldiethylenetriamine, N,N-dimethylcyclohexylamine, N,N-dimethylcyclohexylamine, N,N,N',N'-tetramethyl-1,3-butanediamine, N,N-dimethylbeta-phenylethylamine and 1,2-dimethylimidazole. Suitable tertiary amine activators which contain hydrogen atoms which are reactive with isocyanate groups include, e.g., triethanolamine, triisopanolamine, N,N,N',N'-dimethylethanolamine, N-methyldiethanolamine, N-ethyl-diethanolamine and their reaction products with alkylene oxides, e.g., propylene oxide and/or ethylene oxide.

(b) Organo-metallic compounds, preferably organo-tin compounds such as tin salts of carboxylic acids, e.g., tin acetate, tin octoate, tin ethyl hexoate, tin laurate and the dialkyl tin salts of carboxylic acids, e.g., dibutyl tin diacetate, dibutyl tin dilaurate, dibutyl tin meleate or diocyl tin diacetate.

(c) Silaamines with carbon-silicon bonds as described, e.g., in British Pat., No. 1,090,589, may also be used as activators, e.g., 2,2,4-trimethyl-2-silamorpholine or 1,3-diethylaminomethyl-tetramethyldisiloxane.

(d) Other examples of catalysts which may be used according to the invention and details of their action are described in Kunststoff-Handbuch, Volume VIII, published by Vieweg and Hochtlen, Carl-Hanser-Verlag, Munich, 1966, on pages 96 and 102.

8. 0.001% to 10% by weight, based on the reaction mixture, of an activator (catalyst) listed above.

9. Water containing 20% to 70% by weight of a water-binding agent which is capable of absorbing water to form a solid or a gel, such as hydraulic cement, synthetic anhydrite, gypsum or burnt lime.

10. Water containing 1% to 10% by weight of bases which contain nitrogen such as tetraalkyl ammonium hydroxides.

11. Water containing 1% to 10% by weight of alkali metal hydroxides such as sodium hydroxide, alkali metal phenolates such as sodium phenolate or alkali metal alcoholates such as sodium methylate.

12. Water containing sodium polysulfide in the amount of 1% to 10% by weight.

Surface-active additives (emulsifiers and foam stabilizers) may also be used, according to the invention. Suitable emulsifiers are, e.g., the sodium salts of ricinoleic sulphonates or of fatty acids or salts of fatty acids with amines, e.g., oleic acid diethylamine or stearic acid diethanolamine. Other surface-active additives are alkali metal or ammonium salts of sulphonic acids, e.g., dodecylbenzene sulphonic acid or dinaphthyl methane disulphonic acid; or of fatty acids, e.g., ricinoleic acid; or of polymeric fatty acids.

The foam stabilizers used are mainly water-soluble polyester siloxanes. These compounds generally have a polydimethylsiloxane group attached to a copolymer of ethylene oxide and propylene oxide. Foam stabilizers of this kind have been described, e.g., in U.S. Pat. No. 3,629,308. These additives are preferably used in quantities of from 0% to 20% by weight, based on the reaction mixture.

Negative catalysts, for example, substances which are acidic in reaction, e.g., hydrochloric acid or organic acid halides, known cell regulators, e.g., paraffins, fatty alcohols or dimethyl polysiloxanes, pigments or dyes, known flame-retarding agents, e.g, tris-chlorethylphosphate or ammonium phosphate and polyphosphates, stabilizers against aging and weathering, plasticizers, fungicidal and bacteriocidal substances and fillers, e.g., barium sulphate, kieselguhr, carbon black or whiting, may also be used, according to the invention.

Further examples of surface-active additives, foam stabilizers, cell regulators, negative catalysts, stabilizers, flame-retarding substances, plasticizers, dyes, fillers, fungicidal and bacteriocidal substances, details about methods of using these additives, and about their action, may be found in Kunststoff-Handbuch, Volume VI, published by Vieweg and Hochtlen, Carl-Hanser-Verlag, Munich, 1966, on pages 103 to 113. The halogenated paraffins and inorganic salts of phosphoric acid are the preferred fire-retardant agents.

Particularly important and preferred are those additives which result in an even greater improvement in the fire characteristics of the product. These include not only the conventional flameretarding agents, but also, in particular, halogenated paraffins and inorganic salts of phosphoric acid.

According to the invention, it has been further found that it is favorable to carry out the reaction in the additional presence of a compound acting as hardening agent and lowering the pH of the reaction mixture. Suitable compounds of this type include, depending on the reaction mixture employed, ammonium chloride, barium chloride, barium nitrate, bleaching earths, disodium phosphate, calcium-magnesium carbonate, calcium bromide, calcium chloride, calcium iodate, potash alum, potassium fluoride, potassium borofluoride, potassium bromide, potassium carbonate, potassium metabisulfite, potassium silicofluoride, magnesium carbonate, magnesium fluoride, magnesium oxide, magnesium phosphate, monoammonium phosphate, monosodium phosphate, sodium antimonate, sodium acetate, sodium bichromate, sodium bifluoride, sodium bisulfate, sodium bromide, sodium fluoride, sodium hexametaphosphate, tetrapotassium pyrophosphate, zinc acetate, zinc carbonate and boric acid. The hardening agent may be added to Components C or D in an amount sufficient to lower the pH to 7 to 8.

SUMMARY OF THE INVENTION

I have discovered that a broken-down alkali metal lignin-cellulose product, an organic polyisocyanate and an amphiphilous organic compound will react chemically to produce a polyisocyanate lignincellulose plastic product.

The preferred method is to react a polyisocyanate and/or isocyanate-terminated polyurethane prepolymer of Component B with a broken-down alkali metal lignin-cellulose polymer or Component A to produce a polyisocyanate alkali metal cellulose prepolymer and/or polyurethane, alkali metal cellulose prepolymer which is then reacted with an organic compound (or mixture thereof) of Component C and, optionally, a curing agent and/or an activator of Component D to produce a polyisocyanate cellulose solid or cellular solid product.

The proportion, by weight, of Component D when used with Component B is preferably from 1:70 to 80:20, and the quantity of Component C is from 1% to 30% by weight, preferably from 2% to 20% by weight, based on Component B. The proportion is 2 parts by weight of Component A to 1 to 10 Parts by weight of Component B.

In an alternate method, the Components A, B, C and, optionally, D are added simultaneously and mixed homogeneously, and in a short period of time (a few seconds to about 10 minutes), the chemical reaction begins and a solid or cellular solid product is produced.

In another alternate method, the Components A, B, C and a polyol are added simultaneously and mixed homogeneously, and within a few seconds to 10 minutes, the mixture reacts chemically to produce a solid or cellular solid product.

The polyisocyanate may be first reacted with an oxidated silicon compound to produce a polyisocyanate prepolymer which is then reacted with Components A, C and, optionally, D to produce a solid or cellular solid product.

Mixtures which contain more than 30% by weight of water are usually soft, solid products which may be used as putties, surface coatings, adhesive bonds, grouting compositions, caulking compositions and may be used for producing foams by adding a blowing agent. The blowing agents are usually inert liquids with boiling points ranging from -25.degree. C. to 80.degree. C.

The blowing agents used may be, e.g., acetone, ethyl acetate, methanol, ethanol, halogenated alkanes, e.g., methylene chloride, chloroform, ethylidene chloride, vinylidene chloride, monofluorotrichloromethane, chlorodifluoromethane, dichlorodifluoromethane, butane, kexane, heptane or diethyl ether. Compounds which decompose at temperatures above room temperature with liberation of gases, e.g., nitrogen, such as azo compounds, azoisobutyric acid nitrile, may also act as blowing agents. Other examples of blowing agents and details about the use of blowing agents are described in Kunststoff-Handbuch, Volume VII, published by Vieweg and Hochtlen, Carl-Hanser-Verlag, Munich, 1966, on pages 108 and 109, 453 to 455 and 507 to 510.

The proportions of the components may be adjusted to obtain the desired product, ranging from a solid to a highly cellular solid. When water is used, it reacts with the NCO group to produce CO.sub.2 and pores are produced in the product by the evolved CO.sub.2. In certain cases, the CO.sub.2 is rapidly evolved and escapes before the product hardens so that a solid product can be produced nearly completely free of air cells. The hardening times generally increase with decreasing proportions of Component C.

Powdered calcium, magnesium, aluminum or zinc may be used and will react with the alkali metal ions to bring about the evolution of hydrogen which