Cold flow of glassy polymers. II: Ductility, impact resistance, and unoccupied volume

Abstract

Abstract A definition of maximum fractional unoccupied volume, f = 1.0 – (da/dc), is presented for amorphous crystallizable polymers, f differs for various polymers at Tg, depending on the conformability of the polymer. It is large, at T, for sterically hindered or bulky polymers but low for flexible polymers. There is a reasonably good correlation between f and impact strength. In addition, one can explain the effect of “antiplasticizers.”