Modeling Thermal Properties for Copolymers Covering a Comonomer Composition Range up to 20%

Abstract

Differential scanning calorimetry (DSC) analysis for ethylene/propylene copolymers synthesized in the whole composition range with a supported metallocene catalyst has been carried out. The melting/crystallization process can be determined both in the ethylene and propylene rich regions covering a comonomer composition range of up to 20%. Two peaks are detected showing two different transitions (Tm1 and Tm2). A procedure is developed for modeling DSC melting curves by using a model previously reported by Kissin. Two contributions are considered for the copolymer crystallization in connection with a random comonomer distribution. Such model favourably describes experimental DSC curves and Tm1 and Tm2 values. The obtained parameters follow a regular trend in accordance with its physical meaning. Standard deviation for melting temperatures reveals accurate calculated values. The analysis of the parameter trend allows a fit against composition and predicting melting temperatures, yielding also accurate values.

The interrelationships between microstructure and melting, crystallization and thermal degradation behaviors of fractionated ethylene/1-butene copolymer

“…As Eq. (5) shows, a logarithmic relationship was obtained for these parameters with the regression coefficient of R 2 ≈ 0.96: Also, the models simulating the thermal properties of ethylene/α-olefin copolymers clearly predict that variations of thermal parameters are strongly dependent on the comonomer contents of copolymers [50,51].…”