Sugar based polymers poly

Many ATPS systems contain a polymer which is sugar based and a second one which is of hydrocarbon ether type. Sugar-based polymers include dextran (Dx), hydroxy propyl dextran (HPDx), FicoU (Fi) (a polysaccharide), methyl cellulose (MC), or ethylhydroxyethyl cellulose (EHEC). Hydrocarbon ether-type polymers include poly (ethylene glycol) (PEG), poly (propylene glycol) (PPG), or the copolymer of PEG and PPG. De-rivatized polymers can also be useful, such as PEG-fatty acids or di-ethylaminoethyl-dextran (Dx-DEAE). 

Sugar based polymers, which are obtained by polymerization of vinyl sugars, have recently received increased attention from two viewpoints. One is the development of environmentally friendly material from renewable resources. Another is physiologically active material that mimics carbohydrate on cell surface. This article provides an overview of known sugar based polymers and the recent advances of the poly(vinylalcohol) (PVA) with sugar pendants. 

Poly (Vinylalcohol sugar ester) Figure 10. Strategy for PVA type sugar based polymer... 

Some reviews have been published on the synthetic carbohydrate-based polymers and glycopolymers [11-15]. However, they refer mainly to poly(vinylsaccharide)s and other conventional functionalized polymers having sugars as groups pendant from the main chain of the polymer. In this chapter we shall describe those sugar-based monomers which lead to polymers having the sugar units incorporated into... 

Extrusion is a cost effective manufacturing process. Extrusion is popularly used in large scale production of food, plastics and composite materials. Most widely used thermoplastics are processed by extrusion method. Many biopolymers and their composite materials with petroleum-based polymers can also be extruded. These include pectin/starch/poly(vinyl alcohol) (Fishman et al. 2004), poly(lactic acid)/sugar beet pulp (Liu et al. 2005c), and starch/poly(hydroxyl ester ether) (Otey et al. 1980), etc. In this study, composite films of pectin, soybean flour protein and an edible synthetic hydrocolloid, poly(ethylene oxide), were extruded using a twin-screw extruder, palletized and then processed into films by compression molding process or blown film extrusion. The films were analyzed for mechanical and structural properties, as well as antimicrobial activity. 

Due to abundantly available feedstock and low cost, poly lactic acid (PLA) is one of the most promising bio-based polymers. PLA is obtained by the controlled polymerization of lactic acid monomers which in turn are obtained from renewable resources such as sugar feedstock, wheat, maize, com, and waste products from food or agriculture industry by fermentation (Siracusa et al., 2008). Properties of PLA vary according to the Z - to - D lactylenantiomeric ratio. Table 8 lists some important properties of PLA. 

Kricheldorf [17] studied liquid-crystalline cholesteric copoly(ester-imide)s based on 1 or 2. The comonomers to obtain these chiral thermotropic polymers were N-(4-carboxyphenyl)trimellitimide, 4-aminobenzoic trimellitimide, 4-aminocinnamic acid trimellitimide, adipic acid, 1,6-hexanediol, and 1,6-bis(4-carboxyphenoxyl) hexane. Apparently the poly (ester imide) chains are so stiff that the twisting power of the sugar diol has little effect. 

A polymer much closer to DNA is poly(U). With this polymer, base radicals and base peroxyl radicals abstract an H-atom sugar moiety of the neighboring or a close-by nucleotide [e.g., reaction (10) Deeble and von Sonntag 1984,1986 Deeble et al. 1986]. 

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