私密直播全婐app免费大渔直播,国产av成人无码免费视频,男女同房做爰全过程高潮,国产精品自产拍在线观看

Links
Contact Info.
  • Address:湖南省吉首市吉首大學(xué)化學(xué)化工學(xué)院
  • Zip:416000
  • Tel:07438563911
  • Fax:
  • Email:chemfzhang@163.com
Current Location :> Home > Publications > Text
Isothermal crystallization kinetics of high-flow nylon 6 by differential scanning calorimetry
writer:Fan Zhang, Li Zhou, Yuanqin Xiong, Guangpeng Liu, Weijian Xu
keywords:isothermal crystallization kinetics; nylon 6; differential scanning calorimetry
source:期刊
Issue time:2008年

The isothermal crystallization kinetics was investigated by differential scanning calorimetry for high-flow nylon 6, which was prepared with the mother salt of polyamidoamine (PAMAM) dendrimers and p-phthalic acid, end capping agent and ε-caprolactam by in situ polymerization. The Avrami equation has been adopted to study the crystallization kinetics. Comparing with pure nylon 6, the high-flow nylon 6 has lower crystallization rate, which varies with the generation and content of PAMAM units in nylon 6 matrix. The traditional analysis indicates that the values of Avrami parameters calculated from the half time of crystallization might be more in agreement with the actual crystallization mechanism than the parameters determined from the Avrami plots. The n values of the high-flow nylon 6 range between 2.1 and 2.4, meaning the crystallization of the high-flow nylon 6 is a two-dimensional growth process. The activation energies of the high-flow nylon 6, which were determined by Arrhenius’ method, range between -293 kJ/mol and -382 kJ/mol. The activation energies decrease with the increase in the generation of PAMAM units, but increase with the increase in the content of PAMAM units in nylon 6 matrix.