Cellulose polymers adhesive

The trick, of course, is to find a chemical compound that can be reacted readily with the carbohydrate polymer to give the desired reactive moities along the backbone of the carbohydrate polymer. Here, the adhesives chemist will have to borrow from and extend the work that has been and is now being done on the formation of modified starches 62), cellulosics (48-51,63,64), and textiles. Professor Narayan of Purdue University illustrates the potential adhesive applications of grafted cellulosic polymers in Chapter 24. 

Role of polymer Adhesive/coating/consoli-dant/moulding material A brief description of the tested conservation application is valuable Cellulose acetate was rejected as a picture varnish... 

Sihcone products dominate the pressure-sensitive adhesive release paper market, but other materials such as Quilon (E.I. du Pont de Nemours Co., Inc.), a Werner-type chromium complex, stearato chromic chloride [12768-56-8] are also used. Various base papers are used, including polyethylene-coated kraft as well as polymer substrates such as polyethylene or polyester film. Sihcone coatings that cross-link to form a film and also bond to the cellulose are used in various forms, such as solvent and solventless dispersions and emulsions. Technical requirements for the coated papers include good release, no contamination of the adhesive being protected, no blocking in roUs, good solvent holdout with respect to adhesives appHed from solvent, and good thermal and dimensional stabiUty (see Silicon COMPOUNDS, silicones). 

Thickeners can be added to increase the viscosity of the NR adhesives. Natural materials can be used such as casein or karaya gum, but currently synthetic polymers are used (methyl cellulose and derivatives, polyacrylates). 

The results of mechanical properties (presented later in this section) showed that up to 20 phr, the biofillers showed superior strength and elongation behavior than CB, cellulose being the best. After 30 phr the mechanical properties of biocomposites deteriorated because of the poor compatibility of hydrophilic biopolymers with hydrophobic natural rubber(results not shown). While increasing quantity of CB in composites leads to constant increase in the mechanical properties. Scanning electron micrographs revealed presence of polymer-filler adhesion in case of biocomposites at 20 phr. 

The poor adhesion of carboxymethylcellulose to synthetic fibres means that where such fibres are present, it can only be effective in combination with a synthetic size polymer (Table 10.6). This needs to be taken into account when considering suitable desizing procedures. If this cellulose derivative is to be used in conjunction with an electrolyte-sensitive acrylic acid copolymer, it is advisable to choose a salt-free carboxymethylcellulose. 

Cellulose is a high molecular weight polymer of D-glucose with fi( 1 -4)-glycosidic bonds, found in plant fibres it is the major component of most plant tissues. Starch is another common polysaccharide, containing two polymers of glucose, amylose and amylopectin. It was used in some paint preparations and in the production of paper. Acid treatment of starch produces dextrins, which are used as adhesives and additives in water colour paintings. 

Felix, J.M. and Gatenhobn, P. (1991). The nature of adhesion in composites of modified cellulose fibers and polypropylene. Journal of Applied Polymer Science, 42(3), 609-620. 

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