A study on the crystallinity of ethylene-propylene saturated copolymers (EPR) of industrial source is reported. By DSC, with an appropriate choice of annealing experiments, several crystalline areas are found due to polyethylenic-type sequences of different length. The existance of such ordered sequences is confirmed by NMR data and WAXS analysis. The presence of multiple crystalline regions can be interpreted as due to discontinuous sequences distributions, as confirmed by an EPR simplyfied model made of mixtures of n-alkanes in squalane. An attempt is reported to apply classical theories of crystallization in copolymers to our commercial EPR systems.
Influence of microstructure and sequence length distribution on first-order thermal transition in ethylene-propylene rubbers
1988
Abstract
A study on the crystallinity of ethylene-propylene saturated copolymers (EPR) of industrial source is reported. By DSC, with an appropriate choice of annealing experiments, several crystalline areas are found due to polyethylenic-type sequences of different length. The existance of such ordered sequences is confirmed by NMR data and WAXS analysis. The presence of multiple crystalline regions can be interpreted as due to discontinuous sequences distributions, as confirmed by an EPR simplyfied model made of mixtures of n-alkanes in squalane. An attempt is reported to apply classical theories of crystallization in copolymers to our commercial EPR systems.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
