Investigation of composition heterogeneity of polypentenamers prepared by radiation polymerization

The type of the distribution of stereoregular units in polypentenamers synthesized by γ-irradiation of ciclopentene in the presence of WCl6 has been studied. The phase diagram of systems under consideration was built from the data of scanning calorimetry obtained for polymers with different ratios of cis- and trans-units. The analysis of the diagram and the study of melting of cis- and trans-polypentanamers permit to conclude that as the result of radiation-catalytic polymerization polyblock stereoblock-copolymers are formed. The systems under consideration have the single vitrification temperature which does not depend on the composition. This fact indicates the compatibility of cis- and trans-isomers in amorphous phase. Polymers with predominant content of one isomer have the single melting point close to the melting point of pure stereoisomer. At mean compositions melting of both structures is observed. The results obtained confirm the assumption about two types of active centres of radiation-catalytic polymerization of cyclopentene