Random ethylene/1-hexene copolymers with the 1-hexene content in the range from 2 to 28 mol% were produced with a novel post-metallocene catalyst and analyzed by three techniques, FTIR, 13C NMR, and DSC. The 1-hexene content and the sequence distribution in the copolymers were determined by means of FTIR-M and 13C NMR. The crystallization behavior of the copolymers was studied by DSC under dynamic and isothermal conditions; the Avrami model was used to analyze the crystallization kinetics. It was found that both the 1-hexene content and the crystallization temperature affect the relative crystallinity. The bulk crystallization rate decreases with the 1-hexene content and reduces exponentially with an increase of T c. The melting behavior of isothermally crystallized samples was also investigated and it was found that the melting temperatures of the copolymers under equilibrium conditions were related to the composition
Thermal and structural investigation of random ethylene/1-hexene copolymers with high 1-hexene content
RASPOLLI GALLETTI, ANNA MARIA;BERNAZZANI, LUCA
2014-01-01
Abstract
Random ethylene/1-hexene copolymers with the 1-hexene content in the range from 2 to 28 mol% were produced with a novel post-metallocene catalyst and analyzed by three techniques, FTIR, 13C NMR, and DSC. The 1-hexene content and the sequence distribution in the copolymers were determined by means of FTIR-M and 13C NMR. The crystallization behavior of the copolymers was studied by DSC under dynamic and isothermal conditions; the Avrami model was used to analyze the crystallization kinetics. It was found that both the 1-hexene content and the crystallization temperature affect the relative crystallinity. The bulk crystallization rate decreases with the 1-hexene content and reduces exponentially with an increase of T c. The melting behavior of isothermally crystallized samples was also investigated and it was found that the melting temperatures of the copolymers under equilibrium conditions were related to the compositionI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
