Polymer Biodegradation Mechanisms

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

Saucedo, J.-E. Polymer biodegradation Mechanisms and estimation techniques. 2008, 73, 429-442. 

N. Lucas, C. Bienaime, C. Belloy, M. Queneudec, F. Silvestre, and l.E. Nava-Saucedo, Polymer biodegradation Mechanisms and estimation techniques - A review, Chemosphere, 73 (4), 429-442, 2008. 

Nanocapsules of biodegradable polymers, such as PLA and PLA copolymers or poly (e-caprolactone), have been prepared by an interfacial polymer deposition mechanism [163-166], An additional component, a water-immiscible oil, is added to the drug-polymer-solvent mixture. A solution of the polymer, the drug, and a water-immiscible oil in a water-miscible solvent such as acetone is added to an external... 

As was pointed out in Chapter 10, routes of biosynthesis (anabolism) often closely parallel pathways of biodegradation (catabolism). Thus, catabolism begins with hydrolytic breakdown of polymeric molecules the resulting monomers are then cleaved into small two- and three-carbon fragments. Biosynthesis begins with formation of monomeric units from small pieces followed by assembly of the monomers into polymers. The mechanisms of the individual reactions of biosynthesis and biodegradation are also often closely parallel. However, in most instances, there are clear-cut differences. A first principle of biosynthesis is that biosynthetic pathways, although related to catabolic pathways, differ from them in distinct ways and are often catalyzed by completely different sets of enzymes. 

M. Deng, et al.. In situ porous structures a unique polymer erosion mechanism in biodegradable dipeptide-based polyphosphazene and polyester blends producing matrices for regenerative engineering, Adv. Funct. Mater. 20 (17) (2010) 2794-2806. 

Key words biodegradable polymer, biodegradation, classification of biodegradable polymers, mechanism of biodegradation, testing method, application. 

Various tests and analytical methods are used for the characterisation and evaluation of the properties of vegetable oil-based polymer composites. Mechanical tests for properties such as tensile, flexural, compressive, impact, hardness and wear are carried out by a universal testing machine (UTM), and by equipment for testing impact, hardness, abrasion loss, and so on. Weather and chemical resistance tests are performed in UV/ozone, an artificial environmental chamber and in different chemical media. Water uptake and biodegradability tests are carried out by standard ASTM methods. Biodegradability and biocompatibility may be studied by the same procedure as described in Chapter 2. However, in practice only a few such studies have been performed for vegetable oil-based composites. 

Performance, processability, and price comprise the typical requirements for biodegradable polymers. Performance is based on the ability to perform Ihe necessary functions during the service life as well as the disposal performance, biodegradability. Mechanical strength, processability, moisture and oxygen barrier properties, interactions with the product, printability, sterilizability, transparency, and inert to environmental exposures are a few of the properties necessary to evaluate for the service performance. Due to the variety of applications, it is expected that numerous polymers or formulations will be required to best serve each application. 

---