Chemical modifications of existing polymers: an attempt to increase biodegrad ability

Polymers are a highly diverse class of materials. The applications of polymers are in almost all fields including agricultural (mulching films, green house films, etc), medical (syringes, capsules, medicine packaging, urine bags, etc), and transport (car bumpers, wheel covers), etc. Some polymers are of vital importance however their applications are limited due to non-biodegradability. Polymer possesses a number of reactive functional groups in their structure such as hydroxyl, amino and carboxylic acid group. The chemical modifications using these functionalities may be useful to increase biodegradability and hence the acceptance for pharmaceutical and biomedical use. The aim of the present research was to improve the biodegradability of existing non-biodegradable polymers by chemical modifications.
The polymer blends of polymethyl methacrylate (PMMA) and polyvinyl chlorides (PVC) were prepared separately with chitosan (CS). The prepared blends were characterized for thin layer chromatography (TLC), Fourier transform infrared spectroscopy (FTIR), Differential scanning colorimetry (DSC), Nuclear magnetic resonance (NMR) and hydrolytic and enzymatic degradations. The TLC, FTIR, DSC and NMR analysis revealed the successful formation of PMMA-CS and PVC-CS blend. In the hydrolytic degradation study, the polymer exhibited progressive mass loss over the 8 week period ranging from 1.90% to 45.66%. Similarly, the enzymatic degradation study demonstrated 0.6-4.8% degradation of PMMA-CS blend and 0.3-3% degradation of PVC-CS blend. Thus, chemical modifications could be a promising approach to improve the biodegradability of polymers.