Biodegradability and biodegradation polymers

Presently there are two types of high molecular polymers Non-biodegradable and biodegradable polymer materials... 

Leja, K. Lewandowicz, G. Polymer biodegradation and biodegradable polymers—A review. Polish J. 

Leja, K., and Lewandowicz, G., (2010). Polymer biodegradation and biodegradable polymers—A review, Polish J. Environ. Stud., 19, 255-266. 

Table 10.1 represents the polymers which are used in medical devices. They include both synthetic non-biodegradable and biodegradable polymers. They are mainly used to produce various medical devices such as implants, drug carriers, protective packaging materials, and healthcare items [12]. 

Certain bacterial species produce polymers of y-hydroxybutyric acid and other hydroxyalkanoic acids as storage polymers. These are biodegradable polymers with some desirable properties for manufacture of biodegradable packaging materials, and considerable effort is being devoted by ICI Ltd. and others to the development of bacterial fermentation processes to produce these polymers at a high molecular weight (66). 

There are numerous further appHcations for which maleic anhydride serves as a raw material. These appHcations prove the versatiHty of this molecule. The popular artificial sweetener aspartame [22839-47-0] is a dipeptide with one amino acid (l-aspartic acid [56-84-8]) which is produced from maleic anhydride as the starting material. Processes have been reported for production of poly(aspartic acid) [26063-13-8] (184—186) with appHcations for this biodegradable polymer aimed at detergent builders, water treatment, and poly(acryHc acid) [9003-01-4] replacement (184,187,188) (see Detergency). 

Biodegradable polymers and plastics are readily divided into three broad classifications (/) natural, (2) synthetic, and (J) modified natural. These classes may be further subdivided for ease of discussion, as follows (/) natural polymers (2) synthetic polymers may have carbon chain backbones or heteroatom chain backbones and (J) modified natural may be blends and grafts or involve chemical modifications, oxidation, esterification, etc. 

Heteroatom Chain Backbone Polymers. This class of polymers includes polyesters, which have been widely studied from the initial period of research on biodegradable polymers, polyamides, polyethers, polyacetals, and other condensation polymers. Their linkages are quite frequendy found in nature and these polymers are more likely to biodegrade than hydrocarbon-based polymers. 

Germany, 1990 M. Vert, J. Feijin, A. Albeitsson, G. Scott, and E. ChieUini, eds.. Proceedings of the 2nd International Scientific Workshop on Biodegradable Polymers andPlastic, Monpelier, Prance, Nov. 25—27, 1991, The Royal Society of Chemistry, London, 1992. 

T. Endo and H. Kubota, Mbstracts of the International Symposium on Biodegradable Polymers, Oct. 1990, Tokyo, Japan, pp. 114—119 Y. Saotome, T. Miyazawa, andT. Endo, Chem. Lett. 21 (1991). 

In order to become useful dmg delivery devices, biodegradable polymers must be formable into desired shapes of appropriate size, have adequate dimensional stability and appropriate strength-loss characteristics, be completely biodegradable, and be sterilizahle (70). The polymers most often studied for biodegradable dmg delivery applications are carboxylic acid derivatives such as polyamides poly(a-hydroxy acids) such as poly(lactic acid) [26100-51-6] and poly(glycolic acid) [26124-68-5], cross-linked polyesters poly(orthoesters) poly anhydrides and poly(alkyl 2-cyanoacrylates). The relative stabiUty of hydrolytically labile linkages ia these polymers (70) is as follows ... 

J. E. Glass and G. Swift (eds.) Agricultural and Synthetic Polymers Biodegradability and Utilization. ACS Symp. Series, 433 Washington, DC (1990). 

G. Bohlmann and Y. Yoshida, Biodegradable Polymers, CEH Report, SRI Consulting, Menlo Park, CA, February 2000. 

Nowadays, a strategic area of research is the development of polymers based on carbohydrates due to the worldwide focus on sustainable materials. Since the necessary multi-step synthesis of carbohydrate-based polymers is not economical for the production of commodity plastics, functionalization of synthetic polymers by carbohydrates has become a current subject of research. This aims to prepare new bioactive and biocompatible polymers capable of exerting a temporary therapeutic function. The large variety of methods of anchoring carbohydrates onto polymers as well as the current and potential applications of the functionalized polymers has been discussed recently in a critical review [171]. Of importance is that such modification renders not only functionality but also biodegradability to the synthetic polymers. 

Chiellini E, Solaro R (eds) (2003) Recent Advances in Biodegradable Polymers and Plastics. Wiley-VCH, Weinheim... 

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