期刊
POLYMER DEGRADATION AND STABILITY
卷 95, 期 9, 页码 1789-1793出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.polymdegradstab.2010.05.007
关键词
Di(2-ethylhexyl)phthalate; Poly(vinyl chloride); Evaporation; Gas flow rate; Relative humidity; Plasticizer degradation
The migration of di(2-ethylhexyl)phthalate (DEHP) from poly(vinyl chloride) (PVC) to a surrounding gas phase at temperatures below 120 degrees C kinetically is controlled by evaporation. The effects on the DEHP loss rate of nitrogen flow rate, relative humidity and degradation of the plasticizer at 100 degrees C was assessed. The sample mass decreased linearly with time for both pristine DEHP and plasticized PVC at comparable rates, suggesting that a thin film of DEHP was present on the jacketing insulation during desorption. The latter hypothesis was supported by infrared spectroscopy and by the fact that DEHP is an amphiphilic molecule that will tend to aggregate at the surface with the hydrophobic 2-ethylhexyl units at the air interface. The effect on the migration rate of moisture present in the gas phase was negligible. The DEHP loss rate increased in a retarding non-linear fashion with increasing gas flow rate. In one of the experiments, DEHP was accidently degraded as revealed by discoloration, the presence of low molar mass degradation products (liquid chromatography) containing additional carbonyl groups (infrared spectroscopy) and an increase in the evaporation rate at temperatures between 100 and 130 degrees C. (C) 2010 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据