Please use this identifier to cite or link to this item:
PIRA download icon_1.1View/Download Full Text
Title: Chemical kinetics on thermal oxidative degradation of PMMA
Other Title: 聚甲基丙烯酸甲酯热氧化降解的化学动力学研究
Authors: Zeng, WR 
Li, SF 
Chow, WK 
Issue Date: 2003
Source: 化学物理学报 (Chinese journal of chemical physics), 2003, v. 16, no. 1, p. 64-68
Abstract: 使用质谱、热分析手段研究了PMMA热解反应 .结果表明 ,在氮气中 ,PMMA -CH =CH2 有两个失重阶段 ,分别对应于主链末端双键引发的断链和主链无规则断链反应 ,转折点的失重率约为 2 6 % .其中 ,第一阶段的失重速率受扩散过程控制 ,平均表观活化能E为 15 8.5kJ/mol,lnA为 2 7.6 9;第二失重阶段为 1.5级化学反应 ,平均表观活化能E为 2 14 .79kJ/mol,lnA为 4 0 .4 6 .在空气中 ,PMMA也有两个失重阶段 ,反应机理为 1级化学反应 ,转折点处的失重率约为 70 % .其中在第一失重阶段平均表观活化能E为 130 .32kJ/mol,lnA为 2 4 .81,在此阶段中 ,过氧化基团的分解反应对PMMA的失重速率有重要影响 ;在空气中第二失重阶段平均表观活化能E为 78.2 5kJ/mol,lnA为 13.97.
Effect of oxygen on the thermal degradation of PMM A was studied by mass spectrometry and thermal analysis with TG and DTA. For radic al polymeric PMMA, there were two main degradation models in N 2: the end chai n scission model and the random chain breaking model. The conversion rate at tu rning point was about 26%. Kinetic analysis results indicated the end chain sci ssion was controlled by diffusion process and the average activation energy E was 158.5 kJ/mol and ln A was 27.69. The random chain breaking reaction w as 1.5 order chemical reaction. The average activation energy E and ln A was 214.79 kJ/mol and 40.46, respectively. In air, there were also two stages of mass loss and the turning point conversion rate was about 70%. In the first sta ge, the decomposition of peroxy radicals has a notable effect on the overall deg radation rate. The associated kinetic mechanism was first order chemical reactio n and the average activation energy E was 130.32 kJ/mol and ln A was 24.8 1. In the second stage of mass loss, PMMA had already burnt and the reaction was also first order chemical reaction. The average activation energy and ln A w ere 78.25 kJ/mol and 13.97, respectively.
Keywords: PMMA
Thermal oxidative degradation
Reaction kinetic
Publisher: 中国物理学会
Journal: 化学物理学报 (Chinese journal of chemical physics) 
ISSN: 1003-7713
Rights: © 2003 中国学术期刊电子杂志出版社。本内容的使用仅限于教育、科研之目的。
© 2003 China Academic Journal Electronic Publishing House. It is to be used strictly for educational and research purposes.
Appears in Collections:Journal/Magazine Article

Files in This Item:
File Description SizeFormat 
r13442.pdf170.34 kBAdobe PDFView/Open
Open Access Information
Status open access
File Version Version of Record
View full-text via PolyU eLinks SFX Query
Show full item record

Page views

Last Week
Last month
Citations as of May 28, 2023


Citations as of May 28, 2023

Google ScholarTM


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.