Glass transitions of polyoxetanes

Glass transition data of polyexetanes suggest that the responsible segmental chain motions are rather short range in nature. The incorporation of three different structural features within the repeat unit of a polyoxetane results in three separate and independent transition temperatures. The temperature positions of the transitions arising from different structures within the chain are essentially the same as observed in other polymers with a similar structural element. Structural groups and their corresponding transitions which were studied in combination are: CH 2 CH 2 CH 2 at −125°C., CH 2 OCH 2  at −50 to −70°C., and CH 2 CHCH 3 CH 2  or OCHCH 3 CH 2  at −20 to −30°C.