Polymer stability biological degradation

Polymer degradation refers to any process that breaks down the molecular structure of macromolecules. The main degradation pathways of concern in oil recovery applications are chemical, mechanical, and biological. The research work on polymer stability from the mid-1970s to late-1980s is summarized in Sorbie (1991). 

Although the membrane used for reverse osmosis may be ionic and ion-exchange can occur, there is, however, no overall transmission of salt because of Dorman exclusion (and unlike electrodialysis no electric current is applied). Thus, while an essential requirement of a membrane for reverse osmosis is hydrophilicity, it need not be ionic. In fact, the most successfiil reverse osmosis membranes developed are made of nonionic cellulose acetate. Certain ionic polymers, such as the sufonated polyaromatics, has been used because of their greater chemical stability and resistance to biological degradation. 

Slow biological degradation of tissue-stabilizing polymer matrixes accompanying the healing processes. 

Polymer modifications are intended to impute different, typically desired properties to the new modified material-properties such as enhanced thermal stability multiphase physical responses biological resistance, compatibility or degradability impact response flexibility rigidity etc. 

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