Stretching calorimetry and X-ray characterization of deformational behavior of new high molecular weight propene-carbon monoxide alternating co- and terpolymers

Structure, properties, and deformation behavior of a high molecular weight propene-CO alternating copolymer (EIPCO 200) and ethene-CO/propene-CO terpo lymers (EPEC I; E-CO = 47% and EPEC 2; E-CO = 69%) were investigated. The t erpolymer with high molar ratio of ethene-CO to propene CO (EPEC I) is a ty pical thermoplastic and reveals relatively high crystallinity, while the te rpolymer of Lower content of ethene-CO groups (EPEC I) and the propene-CO c opolymer (EIPCO 200) exhibit elastomeric behavior. In spite of the possible random stereo- and regioregularity, the propene-CO chains crystallize with regular 3/1 chain conformation. According to X-ray data the synthesized te rpolymers consist of blocks of propene-CO segments and blocks enriched with ethene-CO groups. The main structural changes at deformation were studied by means of X-ray diffraction and deformation calorimetry. It is establishe d that the large reversible deformation of the samples studied is determine d mostly by the amorphous regions. Deformation calorimetry results, treated according to the modern theory of thermoelasticty of rubber-like materials , showed that the energy contribution (Delta U/W)(V,T) and the temperature coefficient of the unperturbed dimension of chains d ln[r(2)](0)/dT are mor e negative than for PE and PP, which seems quite reasonable owing to the ch emical structure of the 1,4-polyketone macromolecules.