Quaternary ammonium celluloses

ACS Polymeric Materials Science and Engineering. Fall Meeting 1998. Volume 79. Conference proceedings. Boston, Mas., 23rd-27th Aug. 1998, p.220-1. 012 ANTIMICROBIAL PROPERTIES OF QUATERNARY AMMONIUM CELLULOSE AND CHITOSAN DERIVATIVES Daly W H Guerrini M M Louisiana, State University... 

Recently, we have characterized tertiary amine and quaternary ammonium celluloses made either aqueously or non-aqueously by a variety of instrumental techniques. These techniques have also been used to follow effects of a given anion on the cellulose matrix of a quaternary ammonium cellulose exchanger when the exchanger prepared non-aqueously comes in contact with water. 

Confirmation of the type of titration curve typical of a quaternary ammonium cellulose exchanger was obtained by reacting cotton with trimethylglycidylanmonium chloride and then titrating... 

Figure 5. Potentiometric titration curves of a quaternary ammonium cellulose formed by complete conversion of a cellulose of 2.58% N with CHoI. Curve ABC is for a 0.8043 g sample in base form (1.48 meq) vs 0.1 N HCl. Curve DYEF represents titration of the chloride form in excess HCl (1.72 meq) vs 0.1 N NaOH.

Figure 6. Potentiometric titration curve of a 1.6400 g sample of the quaternary ammonium cellulose. Cel 1-O-CH2CHOHCH2N-(CH3)2 CT, (0.5001 meq N). Curve ABC is for basic form in 50 ml of 1 M NaCl vs 0.1 M HCl, Curve DYEF is for the chloride form in presence of excess HCl (.15 meq) vs 0.1 M NaOH. AB and YE represent titrations of exchangers.

Uniformity of distribution was also indicated by SEM and EDAX data. A mono-quaternary ammonium cellulose anion exchanger (3.46% N, 31.3% I) was exchanged in non-aqueous media with NaSCN. Wet analyses (4.86% N, 0% I, and 5.70% S) indicated it was 100% converted to the thiocyanate form. Ultra-thin cross sections of the fibers in the thiocyanate form examined by EDAX revealed that sulfur was uniformly distributed throughout the fibers. The cross-section of the fiber shown in (Fig. 10) (upper) and EDAX scan (lower) are Illustrative of the uniform distribution of sulfur in a diquaternary ammonium cellulose thiocyanate. This is typical of a quaternary or diquaternary product in the SCN form. 

Figure 11. Light micrographs of fibers from mono-quaternary ammonium celluloses ( 3 27% N) repared nonaqueously from DEAE and CH3I in the I, BH, and SCN forms (left to right) before (upper) and after (lower) immersion in water.

The electro-kinetic properties of DEAE and quaternary ammonium celluloses are also being Investigated via techniques of streaming electrode potentials. However, some difficulties are encountered, particularly in those products of relatively high D.S. that form gels when ground and Immersed in water. 

Daly, W. H., and Guerrini, M. M. (1998). Antimicrobial properties of quaternary ammonium cellulose and chitosan derivatives, Polym. Mater. Set Eng., 79,220-221. 

Polystyrene sulfonate and poly(allylamine hydrochloride) Poly(diallyldimethyl ammonium chloride), poly(allylamine hydrochloride), polyacrylic acid, and polystyrene sulfonate Quaternary ammonium cellulose ether and sodium carboxymethyl cellulose Polystyrene sulfonate and poly(diallyldimethylammonium) chloride... 

The next significant strength improvement followed the 1950 Du Pont (19) discovery of monoamine and quaternary ammonium modifiers, which, when added to the viscose, prolonged the life of the ziac cellulose xanthate gel, and enabled even higher stretch levels to be used. Modifiers have proliferated siace they were first patented and the Hst now iacludes many poly(alkylene oxide) derivatives (20), polyhydroxypolyamines (21—23), and dithiocarbamates (24). 

Another approach for ion-sensing (here copper and zinc) is based on the water-soluble ligand zincon and the ion pair with quaternary ammonium halides shown in Figure 17 which can be homogeneously dissolved in polymers such as plasticized poly(vinyl acetate), ethyl cellulose, and polyurethane. 

The use pattern for methyl chloride in the United States in 1992 and 1995 was (%) methyl chlorosilanes used as intermediates for silicones, 80 methyl cellulose manufacture, 6 quaternary ammonium compounds, 5 agricultural chemicals, 5 butyl rubber production, 2 and miscellaneous, 2 (Anon., 1992, 1995). 

According to the 1981-83 National Occupational Exposure Survey (NOES, 1997), approximately 10 000 workers in the United States were potentially exposed to methyl chloride (see General Remarks). Occupational exposures to methyl chloride may occur in its production and in the production of silicones, methyl cellulose, quaternary ammonium compounds and other chemical agents. Data on workplace exposures to methyl chloride have been presented in a previous monograph (lARC, 1986). 

Theory would predict that PTC should be useful in increasing the alkylation efficiency of hydrophobic electrophiles with cellulose ether alkoxides. However, there is very little previous work reported in using PTC in the preparation of cellulose ethers. Daly and coworkers10 reported that quaternary ammonium salts were useful in catalyzing the heterogeneous benzylation of cellulose, but when we applied this technique to the DPGE alkylation of nascent HEC in aqueous /-butyl alcohol, the presence of catalytic amounts of tetramethylammonium chloride or tetrabutylammonium bromide actually afforded lower alkylation efficiencies. 

The phase transfer catalyzed alkylation reaction of dodecyl phenyl glycidyl ether (DPGE) with hydroxyethyl cellulose (HEC) was studied as a mechanistic model for the general PTC reaction with cellulose ethers. In this way, the most effective phase transfer catalysts and optimum reaction concentrations could be identified. As a model cellulose ether, CELLOSIZE HEC11 was chosen, and the phase transfer catalysts chosen for evaluation were aqueous solutions of choline hydroxide, tetramethyl-, tetrabutyl-, tetrahexyl-, and benzyltrimethylammonium hydroxides. The molar A/HEC ratio (molar ratio of alkali to HEC) used was 0.50, the diluent to HEC (D/HEC) weight ratio was 7.4, and the reaction diluent was aqueous /-butyl alcohol. Because some of the quaternary ammonium hydroxide charges would be accompanied by large additions of water, the initial water content of the diluent was adjusted so that the final diluent composition would be about 14.4% water in /-butyl alcohol. The results of these experiments are summarized in Table 2. 

Figure 6. Effect of sodium acetate on quaternary ammonium hydroxide content in cellulose ether alkylation reactions...

In addition, the quaternary ammonium compounds mostly possess strong affinity for the cellulosic fiber, whereby the insoluble reaction product is anchored even more firmly with the dye on the fiber. This high affinity can, however, also result in nonuniform improvements in fastness properties. This behavior also prevents the use of circulating liquor dyeing machines, because even with addition of aftertreatment agent in portions (e.g., in the case of wound packages) completely uniform aftertreatment can not be guaranteed. 

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