%A LIN Zhidan, ZENG Chunlian, MAI Kancheng
%T Investigation on multiple-melting behavior of nano-CaCO3/polypropylene composites
%0 Journal Article
%D 2007
%J Front. Chem. Sci. Eng.
%J Frontiers of Chemical Science and Engineering
%@ 2095-0179
%R 10.1007/s11705-007-0017-5
%P 81-86
%V 1
%N 1
%U {https://journal.hep.com.cn/fcse/EN/10.1007/s11705-007-0017-5
%8 2007-03-05
%X The multiple melting-peak behavior of polypropylene (PP) in nano-CaCO3/PP composites and modified nano-CaCO3/PP composites were investigated under the condition of isothermal crystallization and nonisothermal crystallization. The result indicated that the addition of nano-CaCO3 markedly increased the crystallization temperatures of PP and induced the formation of the β-crystal of PP. The crystallization temperatures of nano-CaCO3/PP composites modified by reactive monomers were further increased, but the melting-peak intensity of the β-crystal of PP was not greatly influenced. While in the presence of dicumyl peroxide, nano-CaCO3/PP composites modified by reactive monomers led to the significant increase in the melting-peak intensity of the β-crystal of PP. The double melting-peak of PP was observed, which was attributed to the formation of two kinds of different crystallization forms of α-crystal or β-crystal during the crystallization of PP. With the increase of crystallization temperatures, the double melting-peak moved toward the high-temperature side. The intensity of high-temperature melting peak was higher than that of low-temperature melting peak in nano-CaCO3/PP composites. While in modified nano-CaCO3/PP composites crystallized at higher temperature, the intensity of high-temperature melting peak was lower than that of low-temperature melting peak. The isothermal crystallization time had little effect on the melting temperatures.