Nonisothermal crystallization behavior of LLDPE/glass fiber composite

Abstract

The nonisothermal crystallization behavior of linear low-density polyethylene (LLDPE)/glass fiber (GF) composite was investigated by differential scanning calorimetry (DSC). It was observed that the crystallization temperature peak (Tp) of LLDPE composite containing 5.0 wt % GF (LLDPE/GF5) was higher than that of the pure LLDPE at various cooling rates. The half-time of crystallization (t1/2) of LLDPE/GF5 composite was shortened under the effect of GF. The nonisothermal crystallization kinetics of LLDPE and LLDPE/GF5 composite were analyzed through the Avrami, Ozawa, and Mo equations. The results indicated that the data of the nonisothermal crystallization for LLDPE and LLDPE/GF5 composite calculated based on the Ozawa equation did not have the good linear relationship, but the nonisothermal crystallization behaviors of LLDPE and LLDPE/GF5 composite could be successfully described by the modified Avrami and Mo methods. The crystallization rate Zc of the modified Avrami parameter of LLDPE/GF5 composite was higher than that of pure LLDPE at the same cooling rate. The Mo parameter F(T) of LLDPE/GF5 composite was lower than that of LLDPE at the same degree of crystallinity. Through the Kissinger equation, the activation energies Ed of LLDPE and LLDPE/GF5 composite were evaluated, and their values were 312.3 and 251.2 kJ/mol, respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008