Peroxy Radical Formation from Plasma-induced Surface Radicals of Polyethylene as Studied by Electron Spin Resonance.
Peroxy Radical Formation from Plasma-induced Surface Radicals of Polyethylene as Studied by Electron Spin Resonance.
复制标题
DOI：
10.1021/ma970937t
复制
发表时间：
1998-04
期刊：
影响因子：
5.5
通讯作者：
M. Kuzuya;S. Kondo;M. Sugito;T. Yamashiro
中科院分区：
文献类型：
--
作者：
M. Kuzuya;S. Kondo;M. Sugito;T. Yamashiro
利用电子自旋共振和计算机模拟研究了等离子体诱导低密度聚乙烯（LDPE）和高密度聚乙烯（HDPE）表面自由基形成过氧自由基的性质。研究发现，等离子体辐照PE （LDPE和HDPE）中，过氧自由基的形成随组分自由基结构的变化而变化：在三种等离子体诱导的PE自由基中，悬空键位点（DBS）在与氧接触时瞬间转化为相应的过氧自由基，而中链烷基自由基在LDPE和HDPE中与氧的反应活性都很低。计算机模拟结果表明，LDPE和HDPE中过氧自由基的ESR谱相似，由于过氧自由基捕获位点的分子运动自由度不同，两者均由两种谱组成，即部分g平均各向异性谱和近各向同性单线谱。
The nature of peroxy radical formation from plasma-induced surface radicals of polyethylene (PE), both low-density polyethylene (LDPE) and high-density polyethylene (HDPE), was studied by electron spin resonance with the aid of systematic computer simulations. It was found that peroxy radical formation varies with the structure of component radicals of plasma-irradiated PE, both LDPE and HDPE: Among three plasma-induced radicals of PE, dangling bond sites (DBS) undergo an instant conversion into the corresponding peroxy radicals in contact with oxygen, while the midchain alkyl radical is of very low reactivity with oxygen in both LDPE and HDPE. Computer simulations disclosed that ESR spectra of peroxy radicals are similar to each other in LDPE and HDPE, both being composed of two types of spectra, a partial g-averaging anisotropic spectrum and a nearly isotropic single line spectrum due to different molecular motional freedom at the trapping sites of peroxy radicals.