Polystyrene mechanical degradation

Free radicals are also produced by chain scission during deformation of polyethylene and FT-IR has been used to follow this process 237). The polyethylene samples were unaxially drawn and the resultant spectra corrected for orientation. An increase in the vinyl and methyl end groups created by decay of the free radicals occured in going from draw ratios of 5 to 20 44). A similar study involving deformation was made of polystyrene 246) and a comparison demonstrated between the results of thermal and mechanical degradation 24S. ... 

In order to obtain solutions with the desired flow properties, degradation must be avoided. It is, therefore, important to have a knowledge of the conditions, under which chain-scission occurs. Narrow MWD polystyrene was chosen for mechanical degradation experiments, in order to simplify the experiment. 

From turbidimetric titration curves, it was deduced that mechanical degradation of polystyrene in the presence of acceptors results in linear chain degradation products, whereas poly(methyl methacrylate) gave branched and cross-linked fragments [45]. 

Journal of Applied Polymer Science 73,No.7, 15thAug.l999, p.1139-43 MECHANISM STUDIES ON THE CATALYTIC DEGRADATION OF WASTE POLYSTYRENE INTO STYRENE IN THE PRESENCE OF METAL POWDERS... 

Antony, P., Puskas, J.E., and Kontopoulou, M. The Rheological and Mechanical Properties of Blends Based on Polystyrene-Polyisobutylene-Polystyrene Triblock Copolymer and Polystyrene. Proceedings of MODEST, International Symposium on Polymer Modification, Degradation and Stabilization, Budapest, Hungary, 2002. 

Yu, J., Yi, B., Xing, D., Liu, R, Shao, Z. and Fu, Y. 2003. Degradation mechanism of polystyrene sulfonic acid membrane and application of its composite membranes in fuel cells. Physical Chemistry Chemical Physics 5 611-615. 

Polystyrene latices can be prepared by the dispersion polymerisation of styrene in alcohol/water mixtures containing polyelectrolytes. The experimental data obtained lend support to the hypothesis that the polymerisation mechanism which operates is analogous to that which occurs in the non aqueous dispersion polymerisation of methyl methacrylate in solutions of degraded... 

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