Analysis of weathering of a thermoplastic polyester elastomer II. Factors affecting weathering of a polyether-polyester elastomer

To compare the contribution of degradative factors to weathering of a therm oplastic polyester elastomer (TPEE) photo-, thermal conditions and water we re selected as the degradative factors. Experiments on photodegradation, th ermal degradation and hydrolysis of TPEE were carried out. Spectral irradia tion using sharp-cut filters with a xenon lamp, photodegradation under seve ral temperature conditions and immersion in water during photoirradiation w ere also performed. The results of these experiments were compared with tho se of outdoor and accelerated weathering tests. The following conclusions w ere obtained under the experimental conditions: (1) a major factor of the d egradation are ultraviolet rays below 310 nm; (2) an increase in temperatur e accelerates the rate of degradation reaction; and (3) the presence of wat er increases the amount of gel formation caused by cross-linking reaction. (C) 1999 Elsevier Science Ltd. All rights reserved.