摘要
通过牵拉伸及傅立叶变换红外光谱测试 ,分析了三种不同农用聚乙烯地膜样品在人工加速老化实验中的光热降解特性。结果表明 ,光照过程中 ,降解和交联交替控制着反应过程 ,铜川煤在三种农膜中引发自由基反应 ,导致聚乙烯大分子断链、交联、接枝 ,且引入羰基 ;羰基指数并不随铜川煤加入量的增大而增加 ,而是有一个适量点 ,含量为 12 5 %的农膜降解效果优于 7 5 %和 17 5 %。随着光照进行 ,分子链发生脱羰基反应 ,聚合物放出小分子如CO2 、H2 O等 ,大分子链断裂成小分子链 ,力学性能下降。前三周期是三种地膜的氧化诱导期 ,在第三周期即光照时间
Experiments of stetch and fourier transform infrareds pectroscopy were assayed and analyzed properties of photo-thermal degradation process of three polyethylene films for agriculture application in the photodegradable duration of artificially accelerated climate.The results indicated that degradation and crosslinking controlled reaction process alternatively in the euphotic process.Tongchuan coal in the films produced free radical reactions in the euphotic process. Macromolecules of polyethylene occured chain rupture、cross linking and grafting, then led in carbonyl. Furthermore, carbonyl index with accession of Tongchuan coal content was not increasing, but had a quantum sufficit. With euphotic proceeding, moleculer chain produced the reaction of decarbonylation. At the same time, micromolecules such as CO 2、H 2O et al were set loose. Macromolecule chains were broken up into many micromolecule ones, by the way the mechanics performance decreased.Three periods before were induction period of oxidization.After 72 hours mulching films went into shortbread.
出处
《化工新型材料》
CAS
CSCD
2004年第11期51-53,共3页
New Chemical Materials
基金
国家自然科学基金 2 0 2 760 56
