Non-isothermal Crystallization Kinetics of Short Bamboo Fiber-reinforced Recycled Polypropylene Composites

作者：Nguyen Tri Phuong; Gilbert Villoutreix^*

来源：Journal of Reinforced Plastics and Composites, 2010, 29(17): 2576-2591.

DOI：10.1177/0731684409355604

• recycled polypropylene
• short bamboo fibers
• non-isothermal crystallization

This work presents some results on the non-isothermal crystallization kinetics of a recycled polypropylene (RPP) and recycled polypropylene/short bamboo fiber (RPPSBF) composites by using the differential scanning calorimetry at four different cooling rates (5, 10, 20, 40 degrees C/min). Ozawa, Avrami, Jeziorny, Kissinger models, and Lui's approach were applied to describe the non-isothermal crystallization process of these materials. It was found that the Ozawa model was not applicable in the case of bamboo fiber/RPP composites. In contrast, both Avrami model and Lui's approach were successfully used to describe the non-isothermal crystallization process. Determination of the half-time of crystallization (t(0.5)) values and other kinetic parameters, such as Z(t), Z(c), and F(T), showed that the presence of bamboo fibers in RPP matrix increased the crystallization rates and decreased crystallization times of overall cooling rates studied. The nucleation activity (phi) of bamboo fibers, which was calculated by using the Dobreva and Gutzow's equation, indicated that short bamboo fibers acted as the nucleation agents in the RPP matrix to accelerate the crystallization, and the growth of the spherolites appeared to be 3D. The activation energies (E), which characterize the overall non-isothermal crystallization of RPP and short bamboo fiber-reinforced RPP composites, are also evaluated by using the Kissinger model, and found to be 269.05; 268.02; 265.87 kJ/mol for neat RPP and composites samples containing 20 and 50 wt% short bamboo fibers, respectively.

• 出版日期2010-9