Poly biodegradable polymers

The design of biodegradable nano-hybrids has also been reported by Rhee et al. by the combination of a CaO-Si02 component with the biodegradable polymer, poly (epsilon-caprolactone) [30]. These nano-hybrids show hydroxyapatite-forming ability and are expected to show bioactivity and biodegradability. 

The present study investigates a biodegradable polymer, poly(DL-lactic acid) (DL-PLA), as the microcapsule wall. Tablets of microcapsules prepared with this method should be capable of use as subcutaneous implants. Three different compression forces, 2, 5 and 10 kN, were used, with core wall ratios of 1 1 and 2 1. For comparison, the same proportions of drug and coating polymer were compressed without prior microencapsulation. 

Mao H-Q, Kadivala I, Leong KW, Zhao Z, Dang W. Biodegradable polymers poly (phosphoester)s. In Mathiowitz E, ed. The Encyclopedia of Controlled Release. New York Wiley, 1999 45-60. 

In the current industrial process, nisin is manufactured by fermentation of L. lactis subsp. lactis in a milk-based medium. Biosynthesis of nisin is coupled with the growth of lactic acid bacteria and the production of a significant amount of lactic acid (7). Lactic acid is an important chemical for food processing. It can also be used as a raw material in the production of the biodegradable polymer poly(lactic) acid (12). Unfortunately, lactic acid is not recovered in the current nisin process. 

The blending of different polymers is a frequently used technique in industrial polymer production to optimize the material s properties. The biodegradable polymer poly(3-hydroxybutyrate) (PHB) [45, 46], for example, which can be produced by bacteria from renewable resources, has the disadvantage of being stiff and brittle. The mechanical properties of PHB, however, can be readily enhanced by blending with another biopolymer, poly(lactic acid) (PLA) [47]. In order to prepare the optimum blend, it must be noted that the miscibility of different polymers depends on their concentration, the temperature, and their structural characteristics [48]. 

Keywords Biodegradable polymers, Poly(2-hydroxypropionic acid) (PLA), Poly (3-hydroxybutyric acid) (PHB), Processing, Structural characterization... 

Suzuki K, Price JC. Microencapsulation and dissolution properties of a neuroleptic in a biodegradable polymer, poly(d,l-lactide). Journal of Pharmaceutical Sciences. January 1985 74(l) 21-24. PubMed PMID 2858575. 

Polyol monomer like xylitol was also used to compose biodegradable polymer poly(xylitol citrate) (PXC) with citric acid by a simple thermal polycondensation. The abundant pendent hydroxyl groups on PXC, mostly introduced by xylitol, were used to react with methacrylic anhydride to obtain double bond functional PXC (PXCma), which can be formed into a bioelastomer network by photo-cross-linking [96]. 

Another biodegradable polymer, poly(L-lactide) (PLLA), was also grafted from MWCNT surfaces successfully using Sn(Oct)2 as the catalyst. Upon... 

Wang et al. (2009a) have compatibilized the biodegradable polymers poly(L-lactic acid) and poly(butylene succinate) in the presence of DCP radical initiator (0.05-0.2 phr). For related work, see Lan et al. (2013). 

Synthetic biodegradable polymers. Poly (8)-caprolactone), used in the manufacture of seeding pots, is susceptible to hydrolysis of the ester linkage by microbes. Other materials in this category include poly(tetramethylene adipate), block copolymers of poly(ethylene succinate) and poly(ethylene glycol), and block copolymers of poly(tetramethylene glycol) and poly(ethylene succinate). Copolymers based on lactic acid have also been synthesised. 

Khanna S, Srivastava AK. Continuous cultivation of Wautersia eutropha for the production of a biodegradable polymer poly-P-hydroxybutyrate. AsPacJ Mol Biol Biotechnol 2010 18 31-3. 

Lim Y-B, Kim C-H, Kim K, Kim SW, Park J-S (2000) Development of a safe gene delivery system using biodegradable polymer, poly[a-(4-aminobutyl)-L-glycolic acid]. J Am Chem Soc 122 6524-6525... 

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