Journal of Zhejiang University SCIENCE A
(Monthly)

2006   Vol. 7   Suppl. II   p. 330-334

Additive effects of N,N,N′,N′-tetraalkyl terephthalamide on crystalline morphology and mechanical properties of polypropylene

Shentu Bao-Qing^†, Li Ji-Peng, Weng Zhi-Xue

(Polymer Reaction Engineering Division, State Key Laboratory of Chemical Engineering, Department of Chemical and Biochemical Engineering, Zhejiang University, Hangzhou 310027, China)
^†E-mail: shentu@zju.edu.cn
Received Dec. 28, 2005 revision accepted Feb. 20, 2006

Abstract: The effect of N,N,N′,N′-tetraalkyl terephthalamide (TATA) on the crystallization of polypropylene (PP) was studied by means of differential scanning calorimetry, wide angle X-ray diffraction and polarized optical microscopy. It was found that the addition of TATA effectively induced the formation of β-crystalline form of PP. With the increase of TATA content both the total crystallinity degree (x) and crystallinity degree for β-crystalline form (x_β) of PP increased significantly, while the crystallinity degree for α-crystalline form (x_α) decreased. Polarized optical micrographs indicated that the addition of TATA led to a substantial decrease in the size of spherulites of PP and the boundaries of spherulites were hardly distinguished. TATA could significantly improve the impact strength, flexural strength and modulus of PP, while the tensile strength of PP did not change greatly with TATA content.

Key words: Polypropylene (PP), N,N,N′,N′-tetraalkyl terephthalamide, Crystallization, Morphology, Mechanical property
doi:10.1631/jzus.2006.AS0330             CLC number: O631

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