GLUCOSE COPOLYMER

Key Words Epoxy resin, Carboxyl functionalized glucose copolymer, Curing characteristics. Water absorption behavior... 

Isolated chitins are highly ordered copolymers of 2-acetamido-2-deoxy-/3-D-glucose and 2-amino-2-deoxy-j6-D-glucose. The occurrence of the latter is explained by the fact that in vivo chitin is covalently finked to proteins via the nitrogen atom of approximately one repeating unit out of ten, therefore upon isolation a degree of deacetylation close to 0.10 is found. Chito-biose, 0-(2-amino-2-deoxy-j6-D-glucopyranosyl)-(l 4)-2-amino-2-deoxy-... 

A further development [27] is the formation of so-called sugar-acrylate copolymers in which acrylic acid is copolymerised with glucose or other saccharides. Unlike other sequestering agents these polymers are said to be readily biodegradable, this being the main reason for their development. 

There is considerable interest in synthesizing copolymers. This is actually possible if organisms are confronted with mixtures of so-called related and unrelated substrates. Copolymers can also be synthesized from unrelated substrates, e.g., from glucose and gluconate. The 3-hydroxydecanoate involved in the polyester is formed by diversion of intermediates from de novo fatty-acid synthesis [41,42]. Related , in this context, refers to substrates for which the monomer in the polymer is always of equal carbon chain length to that of the substrate offered. Starting from related substrates, the synthesis pathway is closely connected to the fatty-acid /1-oxidation cycle [43]. In Pseudomonas oleovor-ans, for example, cultivated on octane, octanol, or octanoic acid, the synthesized medium chain length polyester consists of a major fraction of 3-hydroxyoc-tanoic acid and a minor fraction of 3-hydroxyhexanoic acid. If P. oleovorans is cultivated on nonane, nonanol, or nonanoic acid, the accumulated polyester comprises mainly of 3-hydroxynonanoate [44]. 

Pseudomonas sp. 61-3 produced a blend of P(3HB) homopolymer and P(3HB-co-3HA) copolymer from sugars such as glucose, fructose, and mannose... 

The living character of the ROMP promoted by the initiator Ru(CHPh)(Cl)2 (PCy3)2 (Cy = cyclohexane) was tested with the synthesis of diblock, triblock, and tetrablock copolymers of norbornene derivatives carrying acetyl-protected glucose, [2,3,4,6-tetra-O-acetyl-glucos-l-O-yl 5-norbornene-2-carboxylate], A or maltose groups, [2,3,6,2/,3/,4/,6/-hepta-0-acetyl-maltos-1-O-yl 5-norbornene-2-carboxylate], B, shown in Scheme 41 [102]. The AB, ABA, and ABAB structures were prepared by sequential addition of monomers with narrow molecular weight distributions to quantitative conversions. 

For the hydrosilylation reaction various rhodium, platinum, and cobalt catalysts were employed. For the further chain extension the OH-functionalities were deprotected by KCN in methanol. The final step involved the enzymatic polymerization from the maltoheptaose-modified polystyrene using a-D-glucose-l-phosphalc dipotassium salt dihydrate in a citrate buffer (pH = 6.2) and potato phosphorylase (Scheme 59). The characterization of the block copolymers was problematic in the case of high amylose contents, due to the insolubility of the copolymers in THF. 

Q. Deng, B. Li, and S. Dong, Self-gelatinizable copolymer immobilized glucose biosensor based on Prussian Blue modified graphite electrode. Analyst 123, 1995-1999 (1998). 

X. Chen and S. Dong, Sol-gel-derived titanium oxide/copolymer composite based glucose biosensor. 

Following the discovery of the unique electronic properties of polypyrrole, numerous polymers of pyrrole have been crafted. A copolymer of pyrrole and pyrrole-3-carboxylic acid is used in a glucose biosensor, and a copolymer of pyrrole and A-methylpyrrole operates as a redox switching device. Self-doping, low-band gap, and photorefractive pyrrole polymers have been synthesized, and some examples are illustrated [1,5]. 

More complex polysaccharides play important roles in connective tissues and elsewhere. For example, hyaluronic acid is universally present in connective tissues of animals, as well as in their vitreous and synovial fluids. It helps to provide the fluids present in joints with shock-absorbing and lubricating properties. Unlike cellulose, chitin, starch, and glycogen, hyaluronic acid contains two different monomers glucose and N-acetylglucosamine alternate in the structure. Thus, hyaluronic acid is a regular alternating copolymer ABABABA —... 

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