Premium
Nonisothermal crystallization of high density polyethylene and nanoscale calcium carbonate composites
Author(s) -
Huang JiannWen,
Wen YaLan,
Kang ChiunChia,
Tseng WeiJen,
Yeh MouYung
Publication year - 2008
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.21087
Subject(s) - high density polyethylene , materials science , crystallinity , crystallization , maleic anhydride , nucleation , differential scanning calorimetry , spherulite (polymer physics) , polyethylene , calcium carbonate , nanocomposite , composite material , chemical engineering , polymer chemistry , polymer , copolymer , chemistry , organic chemistry , thermodynamics , physics , engineering
Abstract Nonisothermal crystallization of high density polyethylene (HDPE)/maleic anhydride‐modified HDPE(manPE)/nanoscale calcium carbonate (CaCO 3 ) nanocomposite was investigated by means of wide angle X‐ray diffraction (WAXD), polarized optical microscopy (POM), and differential scanning calorimetry (DSC). WAXD indicated that the crystallinity was reduced with the addition of CaCO 3 . The spherulite size of HDPE increased in the presence of manPE, but decreased when CaCO 3 was added from observation of POM. A modified Avrami analysis, Ozawa analysis, and Liu analysis were applied to the nonisothermal crystallization process. Crystallizability followed the order: HDPE/manPE/CaCO 3 > HDPE/CaCO 3 > HDPE/manPE > HDPE when undercooling was taken into account. Dependence of the effective activation energy on the relative crystallinity was estimated by the Friedman equation, and the results were used to calculate the parameters ( K g and U *) of Lauritzen‐Hoffman's equation by Vyazovkin's method. These results indicate that the addition of maleic anhydride groups and CaCO 3 tend to promote the nucleation of spherulites on their surfaces and lead to epitaxial growth of the crystallites. But at the same time, manPE and CaCO 3 particles may hinder the transport of the molecule chains resulting in a decrease of the crystallization growth rate. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers