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Indexed by:期刊论文

Date of Publication:2014-04-01

Journal:POLYMER TESTING

Included Journals:SCIE、EI

Volume:34

Page Number:131-139

ISSN No.:0142-9418

Key Words:Isotactic polypropylene; Zinc phenylphosphonate; Crystallization kinetics; Nucleation; Morphology

Abstract:The effect of layered metal phosphonate, zinc phenylphosphonate (PPZn), on the crystallization behavior of isotactic polypropylene (iPP) was investigated by differential scanning calorimetry. PPZn shows excellent nucleating effect on iPP. The nucleation efficiency of the composites reaches 32% even at very low loading of 0.02 wt% PPZn. For 0.1 wt% PPZn, the crystallization half-time of the composite decreases from 19.42 to 1.87 mm at 134 degrees C, compared with pure iPP. The isothermal crystallization data were further analyzed by the Avrami model. The values of the Avrami exponent of the composites are comparable to that of pure iPP, indicating that the presence of PPZn does not change the crystallization mechanism of the matrix. The presence of PPZn increases significantly the nuclei density of iPP but has no discernible effect on its crystalline structure, evidenced by polarized optical microscopy and wide angle X-ray diffraction measurements. (C) 2014 Elsevier Ltd. All rights reserved.