Polymer biodegradating

A. Gandini, ACS Symp. Ser. 433,Agric. Synth. Polym. Biodegrad. Util, 195 (1990). 

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

Kravetz L (1990) In Glass JE, Swift G (eds) Agricultural and synthetic polymers biodegradation and utilization. American Chemical Society, Washington, DC, p 96... 

Microspheres made of various polymers biodegradable to nonharm-ful compounds that could be metabolized and/or removed from organisms found many applications in medicine as carriers of drugs or other bioactive compounds [1 ]. Besides chemical composition there are also other properties of microspheres that are of primary importance to their medical applications. In particular, average diameters and diameter distributions illustrated in Table 1 based on data published in [5] are the relationship between the diameters of microspheres and their localization in various cells and tissues of the human body. 

This indicates the possibility of making addition polymers biodegradable by the introduction of ester linkages in to the backbone. Since the free radical ring-opening polymerization of cyclic ketene acetals, such as 2-methylene-1,3-dioxepane (1, Scheme I), made possible the introduction of ester groups into the backbone of addition polymers, this appeared to be an attractive method for the synthesis of biodegradable addition polymers. 

Because enzymes are too big to diffuse into the bulk of a polymer, biodegradation is an erosion process that takes place at the surface of the plastic article [5]. Therefore, the thickness of a plastic article is a decisive parameter in determining the time needed for complete degradation. 

Lucas N, Bienaime C, Belloy C, Queneudec M, Silvestre F, Nava-Saucedo JE (2008) Polymer biodegradation mechanisms and estimation techniques. Chemosphere 73 429 142... 

Plant polymers—Synthesis—Congresses. 2. Plant polymers—Biodegradation—Congresses. 3. Plant Cell Walls—Congresses. 

Polymer Biodegradation Due to Hydrolyzable and Acid-Sensitive Linkages.235... 

Lim Y, Choi YH, Park J (1999) A self-destroying polycationic polymer biodegradable poly (4-hydroxy-L-proline ester). J Am Chem Soc 121 5633-5639... 

Albertsson A-C, Karlsson S (1994) Chemistry and biochemistry of polymer biodegradation. In Griffin GJL (ed), Chemistry and Technology of Biodegradable Polymers. Blackie, Glasgow, chap 2, p 7... 

For much of the last century, scientists attempted to make useful plastics from hydroxy adds such as glycolic and lactic acids. Poly(glycolic acid) was first prepared in 1954, but was not commercially developed because of its poor thermal stability and ease of hydrolysis. It did not seem like a useful polymer. Approximately 20 years later it found use in medicine as the first synthetic suture material, useful because of its tendency to undergo hydrolysis. After the suture has served its function, the polymer biodegrades and the products are assimilated (Li and Vert 1995). Since then, suture materials, prosthetics, artificial skin, dental implants, and other surgical devices made from polymers and copolymers of hydroxy carboxylic acids have been commercialized (Edlund and Albertsson 2002). 

Biodegradability, or the rate of biodegradation, depends on many factors such as the structure of polymers, biodegradation conditions, the hydrophobicity of polymers, filler type and content, the presence of additives and substituents, crystallinity, and the stereoconfiguration of polymers (93,94). Therefore, appropriate measures need to be taken before designing a composite. 

Tokiwa, Y. Ando, T. Suziki, T. Takeda, K. Biodegradation of Synthetic Polymers Containing Ester Bonds in Agricultural and Synthetic Polymers, Biodegradability and Utilization Glass, J. E. Swift, G. (Eds.) ACS Symposium Series 433 ACS Washington, DC 1990. 

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