28 Pages

Degradation Studies of Polyolefins

WithR.G. Austin

Polyolefins are inherently degradable by thermal oxidation or photodegradation but achieving controlled or timely degradation is very difficult. Most suggested applications of polyethylene with enhanced degradability are in packaging and films and the test was used to follow the film's degradation. The effect the additives have on film properties is an important consideration for determining applications, economics, and processibility. Biodegradation is catalyzed by enzymes and its rate greatly depends on environmental conditions such as temperature, oxygen, pH, moisture and a population of microorganisms. The effect of biodegradation on linear low-density polyethylene (LLDPE) molecular weight is shown on a plot of gel permeation chromatographs of pure LLDPE and polymer treated with the biodegradable inoculum for various monthly intervals. The rate of polymer degradation is dependent on UV radiation and other environmental factors such as oxygen, and water. Polymer uses and applications are very diversified and require different levels of performance. Biodegradation of polymers occurs in certain polymers such as polycaprolactone (PCL).