Polymers are widely used in our daily life. However, polymers degradate, The degradation takes different forms, such as fracturing, crucking, and chalking, depending on the nature of polymers, and often involves complex, overlapping and mutually interacting processes. Here, the degradation processes of polymers are reviewed briefly by examples. The methods, currently being used for estimating extents of degradation of polymers, are also included. It is shown that the degradation processes of polymers depend not only on the environments in which they are practically used, but also on their fabrication processes.
