Biodegradation of Natural Polymers

Modified natural polymers offer a way of capitalizing on their well accepted biodegradability of natural polymers to develop environmentally acceptable... 

Growing discussion about the limited availability of cheap fossil basic materials, and customers paying more and more attention to product life cycles, brings aspects of the biodegradability of polymer products again to the focus of attention. The replacement of synthetic polymer products with biopolymers is attractive but limited because the properties of natural polymers do not always fit the demands of processability and final product performance. PVA with its beneficial rheological... 

Though less studied than synthetic polymer and lipid-based gene delivery systems, there have been significant advances in the field of natural polymers for gene delivery. Biodegradable polymers are less likely to accumulate within tissues than their synthetic counterparts. Synthetic polymers are not easily removed by normal clearance systems and can accumulate in tissues. 

Two types of microorganisms are of particular interest in the biodegradation of natural and synthetic polymers these are bacteria and fungi. Many species or types of microorganisms are found broadly in nature. 

Broad interest in the possible biodegradation of synthetic polymers has developed only in recent years and primarily in response to the growing problem of the waste disposal of plastics. Essentially all biopolymers are susceptible to enzymatic degradation because the enzymatic polymerization reactions responsible for their synthesis in nature have closely related counterparts in nature for their enzymatic depolymerization what nature creates, nature can destroy . If it were not so, polymers could not be utilized as reserve materials and waste... 

There is also interest in other sources of natural polymers that are both biobased and biodegradable. Starting materials include chitin, chitosan, casein, hemicellu-lose, and others. None of these materials have yet reached the point of commercial applications as packaging materials. 

As a partial solution to the global issue of plastic waste, in recent years much interest has been devoted to the formulation of environmentally degradable plastic materials. In particular the use of natural polymers presents several advantages such as biodegradability, utilizing of renewable resources, recyclability. At the same time water sensitivity and degradability of natural polymers limit their possible applications. Consequently bioplastics cannot replace synthetic plastics in every application but they can result appropriate in specific products especially for those applications in which recovery of plastics is not economically feasible, viable and... 

The polydispersity of sample A is rather high. This is due to a fimgal infection of the extracted polymer. It seems that the polymer chains did undergo some cleaving by extracellular depolymerases from the fungi, which led to increased PD and a rather low value of Mn. This is a mechanism also responsible for the biodegradation of these polymers in a natural envirorunent. 

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