Methods for Biocompatible Derivatization of Cellulosic Surfaces

Abstract

The present invention describes methods of treating cellulosic materials with a composition that provides increased hydrophobicity to such materials without sacrificing the biodegradability thereof. The methods as disclosed provide for esterification of available hydroxyl groups on cellulosic materials, where such hydroxyl groups are “masked” by bulky organic chains, including that the disclosure provides products made by such methods. The materials thus treated display higher hydrophobicity, barrier function, and mechanical properties, and may be used in any application where such features are desired.

1 . A method for treating a surface of a cellulose-containing material comprising:
 (a) applying to said surface a composition comprising:
 (i) an alkanoic acid derivative having the formula (I):
   R—CO—X
 
 
    wherein R is a straight-chain, branched-chain, or cyclic aliphatic hydrocarbon radical having from 6 to 50 carbon atoms, and wherein X is Cl, Br, or O(CO)OR;
 (ii) a base; and 
 (iii) a first solvent, 
   (b) heating the applied composition on said surface;   (c) rinsing said surface with a second solvent; and   (d) drying said rinsed surface;   
       wherein said composition esterifies at least a portion of the hydroxyl groups available of via the cellulose of the material and said dried surface comprises a water contact angle larger than 90°. 
     
     
         2 . The method of  claim 1 , wherein the cellulose-containing material exhibits greater hydrophobicity relative to the cellulose-containing material without said treating. 
     
     
         3 . The method of  claim 1 , wherein the base is non-nucleophilic. 
     
     
         4 . The method of  claim 1 , wherein the base is organic. 
     
     
         5 . The method of  claim 1 , wherein the base is selected from the group consisting of aziridines, azetidines, piperazines, piperidines, pyridines, bipyridines, terpyridines, dihydropyridines, morpholines, N-alkylmorpholines, 1,4-diazabicyclo[2.2.2]octanes, 1,8-diazabicycloundecanes, 1,8-diazabicycloundecenes, dimethylated pentylamines, trimethylated pentylamines, pyrimidines, pyrroles, pyrrolidines, pyrrolidinones, indoles, indolines, indanones, benzindazones, imidazoles, benzimidazoles, imidazolones, imidazolines, oxazoles, isoxazoles, oxazolines, oxadiazoles, thiadiazoles, carbazoles, quinolines, isoquinolines, naphthyridines, triazines, triazoles, tetrazoles, triethylamines, pyrazoles, pyrazolines, and combinations thereof. 
     
     
         6 . The method of  claim 1 , wherein each of the first and second solvents are is selected from the group consisting of pentane, hexane, heptane, octane, petroleum ether, naphtha, kerosene, petroleum, paraffin oil, benzene, toluene, xylene, mesitylene, ethylbenzene, diethylbenzene, methylene chloride, chloroform, 1,2-dichloroethane, chlorobenzene, carbon tetrachloride, tetrabromoethylene, cyclopentane, cyclohexane, methylcyclohexane, anisole (methyl phenyl ether), tert-butyl methyl ether, dibenzyl ether, diethyl ether, dioxane, diphenyl ether, methyl vinyl ether, tetrahydrofuran, triisopropyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether (diglyme), diethylene glycol monobutyl ether, diethylene glycol monomethyl ether, 1,2-dimethoxyethane (DME, monoglyme), ethylene glycol monobutyl ether, triethylene glycol dimethyl ether (triglyme), triethylene glycol monomethyl ether, acetone, diisobutyl ketone, methyl n-propyl ketone; methyl ethyl ketone, methyl isobutyl ketone, methyl formate, methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, and combinations thereof. 
     
     
         7 . The method of  claim 1 , wherein the cellulose containing material comprises a cellulose selected from the group consisting of nanocellulose, cellulose nanofibres, whiskers or microfibril, microfibrillated or nanofibril cellulose, sugarcane cellulose, cotton or cotton blends, and combinations thereof. 
     
     
         8 . The method of  claim 1 , wherein the cellulose containing material is selected from the group consisting of a carton for food storage, a bag for food storage, a bottle for carbonated liquid storage, a bottle for non-carbonated liquid storage, film for wrapping food, a garbage disposal container, a food handling implement, a fabric fibre, a water storage and conveying implement, alcoholic or non-alcoholic drinks, an outer casing or screen for electronic goods, an internal or external piece of furniture, a curtain, upholstery, and combinations thereof. 
     
     
         9 . A method for treating a surface of a cellulose-containing material comprising:
 (a) applying to said surface a composition comprising:
 (i) (1) an alkanoic acid; and
 (2) a derivatizing agent selected from the group consisting of acid chlorides, acid bromides, acid iodides, anhydrides, ketenes, diketenes, chlorocarbolic acid esters, carbonic acid diesters, 2,5-diketooxazolidines, isatinic anhydride, isocyanates, carbamoyl chlorides, thiocyanates, thiocarbamoyl chlorides, sulfonyl chlorides, sulfonic acid anhydrides, N-chlorosulfonamides, sulfinic acid chlorides, N-chlorosulfinamides, and combinations thereof; 
 
 (ii) a base; and 
 (iii) a first solvent, 
   (b) heating the applied composition on said surface;   (c) rinsing said surface with a second solvent; and   (d) drying said rinsed surface;   
       wherein the resulting surface of the cellulose-based material exhibits a water contact angle larger than 90° and said composition esterifies at least a portion of the hydroxyl groups available of the cellulose of the material. 
     
     
         10 . The method of  claim 9 , wherein said esterified hydroxyl groups are stable up to at least about 200° C. 
     
     
         11 . The method of  claim 9 , wherein the base is selected from the group consisting of aziridines, azetidines, piperazines, piperidines, pyridines, bipyridines, terpyridines, dihydropyridines, morpholines, N-alkylmorpholines, 1,4-diazabicyclo[2.2.2]octanes, 1,8-diazabicycloundecanes, 1,8-diazabicycloundecenes, dimethylated pentylamines, trimethylated pentylamines, pyrimidines, pyrroles, pyrrolidines, pyrrolidinones, indoles, indolines, indanones, benzindazones, imidazoles, benzimidazoles, imidazolones, imidazolines, oxazoles, isoxazoles, oxazolines, oxadiazoles, thiadiazoles, carbazoles, quinolines, isoquinolines, naphthyridines, triazines, triazoles, tetrazoles, triethylamines, pyrazoles, pyrazolines, and combinations thereof. 
     
     
         12 . The method of  claim 9 , wherein each of the first and second solvents are is selected from the group consisting of pentane, hexane, heptane, octane, petroleum ether, naphtha, kerosene, petroleum, paraffin oil, benzene, toluene, xylene, mesitylene, ethylbenzene, diethylbenzene, methylene chloride, chloroform, 1,2-dichloroethane, chlorobenzene, carbon tetrachloride, tetrabromoethylene, cyclopentane, cyclohexane, methylcyclohexane, anisole (methyl phenyl ether), tert-butyl methyl ether, dibenzyl ether, diethyl ether, dioxane, diphenyl ether, methyl vinyl ether, tetrahydrofuran, triisopropyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether (diglyme), diethylene glycol monobutyl ether, diethylene glycol monomethyl ether, 1,2-dimethoxyethane (DME, monoglyme), ethylene glycol monobutyl ether, triethylene glycol dimethyl ether (triglyme), triethylene glycol monomethyl ether, acetone, diisobutyl ketone, methyl n-propyl ketone; methyl ethyl ketone, methyl isobutyl ketone, methyl formate, methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, and combinations thereof. 
     
     
         13 . The method of  claim 9 , where the cellulose containing material comprises a cellulose selected from the group consisting of nanocellulose, cellulose nanofibres, whiskers or microfibril cellulose, microfibrillated or nanofibril cellulose, sugarcane cellulose, cotton or cotton blends, and combinations thereof. 
     
     
         14 . An article of manufacture comprising a surface comprising cellulose, wherein said surface comprises hydroxyl groups in ester linkage with a compound of:
   R—CO—X
   
       wherein R is a straight-chain, branched-chain or cyclic aliphatic hydrocarbon radical having from 6 to 50 carbon atoms, and wherein X is Cl, Br, or O(CO)OR and, said surface comprises a water contact angle larger than 90°. 
     
     
         15 . The article of  claim 14 , where said ester linkage is chemically stable up to temperatures of between about 200° C. to about 250° C. 
     
     
         16 . The article of  claim 14 , wherein water vapour permeability of said surface is between about 10 Barrer units to about 20 Barrer units. 
     
     
         17 . The article of  claim 14 , wherein oxygen permeability of said surface is between about 10 Barrer units to about 20 Barrer units. 
     
     
         18 . The article of  claim 14 , which is biodegradable. 
     
     
         19 . The article of  claim 14 , selected from the group consisting of a carton for food storage, a bag for food storage, a bottle for carbonated liquid storage, a bottle for non-carbonated liquid storage, film for wrapping food, a garbage disposal container, a food handling implement, a fabric fibre, a water storage and conveying implement, alcoholic or non-alcoholic drinks, an outer casing or screen for electronic goods, an internal or external piece of furniture, a curtain, upholstery and combinations thereof. 
     
     
         20 . A method for treating a surface of a cellulose-containing material comprising:
 (a) applying to said surface a composition comprising:
 (i) an alkanoic acid derivative having the formula (I):
   R—CO—X
 
 
    wherein R is a straight-chain, branched-chain, or cyclic aliphatic hydrocarbon radical having from 6 to 50 carbon atoms, and wherein X is Cl, Br, or O(CO)OR;
 (ii) a base; and 
 (iii) a first solvent, 
   (b) heating the applied composition on said surface;   (c) rinsing said surface with a second solvent; and   (d) drying said rinsed surface;   
       wherein said composition esterifies at least a portion of hydroxyl groups available of said cellulose of said material and said dried surface comprises a water contact angle larger than 90°, and one or more of stable up to at least about 200° C., an oxygen permeability of less than about 10 Barrer units, and a water vapour permeability of less than about 20 Barrer units.