Poly degradation assumptions

However, Pacansky and his coworkers77 studied the degradation of poly(2-methyl-l-pentene sulfone) by electron beams and from infrared studies of the products suggest another mechanism. They claim that S02 was exclusively produced at low doses with no concomitant formation of the olefin. The residual polymer was considered to be essentially pure poly(2-methyl-l-pentene) and this polyolefin underwent depolymerization after further irradiation. However, the high yield of S02 requires the assumption of a chain reaction and it is difficult to think of a chain reaction which will form S02 and no olefin. 

As known, polymethacrylates split off only the corresponding monomers. This is reflected in the thermofractogram of a polymer mixture (see Fig. 26 below). There are, nevertheless, characteristic differences between individuals. n-Butyl- and ethyl-methacrylates appear in the form of a double spindle (zones 2 and 1, respectively) whereas decylmethacrylate occurs as a single spindle form (zone 3). Since free monomers cannot be present in the polymer mixture, this finding demands the assumption of two competing fission mechanisms for poly-n-butyl- and polyethylmethacrylates. The chemical structure of the monomer evidently influences appredably the degradation behaviour of polymethacrylates. 

---