標題: A General Approach for Estimating Lamella-Thickness Distribution in Polymers with Low-Frequency Raman Spectroscopy: Application to Lamella Formation in Crystallizing Polyethylene
作者: Samuel, Ashok Zachariah
Hamaguchi, Hiro-o
應用化學系
應用化學系分子科學碩博班
Department of Applied Chemistry
Institute of Molecular science
關鍵字: chain structures;crystal growth;lamella thickness;polymers;Raman spectroscopy
公開日期: 2-Jul-2018
摘要: A general method for estimating lamella-thickness distribution in semicrystalline polymers has been developed and applied to polyethylene (PE). The longitudinal acoustic mode (LAM) of PE appears at very low frequencies (i.e., (v) over tilde8-20 cm(-1)) in the Raman spectrum. It represents a distribution of lamellae of varying thicknesses. We propose a distribution function that converts a low-frequency LAM Raman band into the corresponding lamellae-thickness distribution. By using this distribution function, we can study lamella formation in crystallizing PE to elucidate the influence of supercooling and determine critical lamella thickness, the minimum chain length at which folding occurs, and the associated thermodynamic parameters accurately. This method has a general applicability toward the examination of polymer crystallization in an accurate and straightforward manner. Understanding the molecular details of polymer crystallization has applications, particularly in polymer thin-film photovoltaics and polymer processing, beyond its fundamental academic significance.
URI: http://dx.doi.org/10.1002/chem.201800357
http://hdl.handle.net/11536/145201
ISSN: 0947-6539
DOI: 10.1002/chem.201800357
期刊: CHEMISTRY-A EUROPEAN JOURNAL
Volume: 24
起始頁: 9333
結束頁: 9339
Appears in Collections:Articles