Copolymer biodegradability

Poloxomer and chitosanb graft copolymer biodegradable/bioerodible... 

Polyhydroxybutyrate-valerate copolymer Biodegradable polyester used in degradable plastic... 

Ermak, T.H. et al. Uptake and transport of copolymer biodegradable microspheres by rabbit Peyer s patch M cells. Cell Tissue Res., 279, 2, 1995. 

MAJOR APPLICATIONS Films, formulation of copolymers, biodegradable polyesters, formulation of elastomeric block copolyesters, formation of diol for extension by diisocyanate. 

Tsutsumi et al. reported the biodegradation of statistical copolymers composed of DL-Iactide or L-Iactide and cyclic carbonates in the presence of enzymes such as cholesterol esterase, hpoprotein hpase and proteinase K (Tsutsumi et al., 2002, 2003). All the enzymes exhibit degradative activity to the various copolymers. Biodegradation of P(DLLA-co-TMC) 87/13 and P(LLA-co-TMC) 71/29 is faster than that of PDLLA and PLLA using proteinase K which is known to degrade LLA moieties. 

Poly (glycolide-co-lac-tide-co - caprolactone) copolymer Biodegradable, injection Maintained drug release for at least 14 weeks Reduction of intraocular inflammatory processes... 

Still another use of the presence of a functional group within the backbone of an addition polymer is to render the copolymer biodegradable. When the dimethylene monomer I and hydroxyethyl methacrylate (HEMA) were copolymerized to produce a copolymer containing 14 mol-% of the ring-opened units, hydrolysis of the copolymer in an alcoholic solution containing 1% sodium hydroxide gave within 3 hrs. at room tempera-... 

Polymer—polymer iacompatibiHty encapsulation processes can be carried out ia aqueous or nonaqueous media, but thus far have primarily been carried out ia organic media. Core materials encapsulated tend to be polar soHds with a finite degree of water solubiHty. EthylceUulose historically has been the sheU material used. Biodegradable sheU materials such as poly(D,L-lactide) and lactide—glycoHde copolymers have received much attention. In these latter cases, the object has been to produce biodegradable capsules that carry proteias or polypeptides. Such capsules tend to be below 100 p.m ia diameter and are for oral or parenteral administration (9). 

Lactic acid and levulinic acid are two key intermediates prepared from carbohydrates [7]. Lipinsky [7] compared the properties of the lactide copolymers [130] obtained from lactic acid with those of polystyrene and polyvinyl chloride (see Scheme 4 and Table 5) and showed that the lactide polymer can effectively replace the synthetics if the cost of production of lactic acid is made viable. Poly(lactic acid) and poly(l-lactide) have been shown to be good candidates for biodegradeable biomaterials. Tsuji [131] and Kaspercejk [132] have recently reported studies concerning their microstructure and morphology. 

Zinc carbonate reacts with epoxide to form zinc alkoxide, which in turn reacts with carbon dioxide to regenerate zinc carbonate. The most effective catalyst systems were the reaction products between diethylzinc and polyhydroxy compounds such as water or pdyhydric phenols243,244. This copolymer is interesting as a biodegradable elastomer248. ... 

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