文献类型：期刊文献

英文题名：Controlling sandwich-structure of PET microcellular foams using coupling of CO2 diffusion and induced crystallization

作者：Li, Dachao[1]; Liu, Tao[1]; Zhao, Ling[1]; Yuan, Weikang[1]

机构：[1] State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China

年份：2012

卷号：58

期号：8

起止页码：2512

外文期刊名：AIChE Journal

收录：EI(收录号：20122815241088)

语种：英文

外文关键词：Microcellular radio systems - Diffusion - Suspensions (fluids) - Ethylene - Sandwich structures - Fourier transform infrared spectroscopy - Suspensions (components)

摘要：Controlling sandwich-structure of poly(ethylene terephthalate) (PET) microcellular foams using coupling of CO2 diffusion and CO2-induced crystallization is presented in this article. The intrinsic kinetics of CO2-induced crystallization of amorphous PET at 25°C and different CO2 pressures were detected using in situ high-pressure Fourier transform infrared spectroscopy and correlated by Avrami equation. Sorption of CO2 in PET was measured using magnetic suspension balance and the diffusivity determined by Fick's second law. A model coupling CO2 diffusion in and CO2-induced crystallization of PET was proposed to calculate the CO2 concentration as well as crystallinity distributions in PET sheet at different saturation times. It was revealed that a sandwich crystallization structure could be built in PET sheet, based on which a solid-state foaming process was used to manipulate the sandwich-structure of PET microcellular foams with two microcellular or even ultra-microcellular foamed crystalline layers outside and a microcellular foamed amorphous layer inside.? 2011 American Institute of Chemical Engineers.