Acrylamide sugars, polymers

Both natural polymers such as polysaccharides and synthetic polymers such as polylysine, polyglutamic acid, polyphosphazenes, copolymers of vinylpyrrolidone, copolymers of 2-hydroxypropylmeth-acrylamide, and etc. have been used as drug carriers. The structure of these polymers can be modified by the incorporation of hydro-phobic units, sugar residues, or sulfonyl groups to achieve a specific tissue affinity. 

A disadvantage of traditional acrylamide polymerization reactions is the heterogeneity of the products that result. A radical polymerization method that produces polymers of similar structure but that are much more homogeneous is atom-transfer radical polymerization (ATRP) [155,156]. ATRP has been used to synthesize carbohydrate-substituted polymers with low polydispersities [157,158,159,160,161]. Materials that display sugar residues such as glu-cofuranose [160], glucopyranose [161], and A-acetyl-D-glucosamines [159]. 

MAJOR USES Production of polyacrylamide polymers used as a chemical intermediate in the production of N-methylol acrylamide and N-butoxyacrylamide absorbent in disposable diapers, medical products and agricultural products sugar beet juice clarification adhesives printing ink emulsion stabilizers thickening agents for agricultural sprays. 

The vinyl sugars mentioned above were acrylate, acrylamide, styryl, vinylether and alkenyl sugars, and their polymer backbones after polymerization are not biodegradable. 

Water-soluble 0-glycosyl derivatives of polyacrylamide have been prepared by co-polymerization of acrylamide and allyl glycosides of various sugars. Quantitative precipitin curves obtained with these co-polymers and lectins were similar to those produced by lectins and naturally occurring polysaccharides thus the co-polymers can serve as model substances for lectin interactions. 

Synthetic polymers containing sugar branches have attracted considerable interest in recent years. These are typically produced via chemoenzymatic routes where the first step is the enzyme-mediated synthesis of the sugar ester monomer followed by chemical polymerization (Scheme 2). Several workers have developed sugar ester-abased polymers containing vinyl, styrene, acrylamide, etc., functionalities. A discussion of the synthesis methods of these compounds are not in the scope of the current work and interested readers are referred to some recent literature by Patil et al. [64], Kitagawa and Tokiwa [65], and Raku and Tokiwa [66]. 

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