双固化交联体系对聚烯烃弹性体封装胶膜交联行为及性能的影响

Effects of Dual Curing System on Cosslinking Behavior and Properties of Polyolefin Elastomer Encapsulation Films

以高活性及低活性过氧化物组成聚烯烃弹性体(POE)胶膜双固化交联体系,通过差示扫描量热分析和红外光谱分析了POE胶膜中过氧化物的分解行为,结合胶膜交联程度及性能的测定,研究了双固化交联体系对POE交联行为及胶膜性能的影响。结果表明,单独使用过氧化物交联POE时,交联程度顺序为:叔丁基过氧化碳酸-2-乙基己酯(TBEC)/POE>过氧化-2-乙基己基碳酸叔戊酯(TAEC)/POE>>1,1-二叔丁基过氧化-3,3,5-三甲基环己烷(BPMC)/POE,且3种体系在流延制膜过程中均出现过氧化物提前分解并形成微凝胶的现象。以TBEC和2,5-二甲基-2,5-双(过氧化叔丁基)己烷(DBPH)组成双固化交联体系,在TBEC/DBPH质量比较高时,胶膜交联程度高于TBEC/POE体系,透光率、拉伸强度、剥离强度和耐老化性能均有提高,流延制膜过程中的微凝胶得到抑制;当双固化交联体系中TBEC/DBPH质量比小于1.5/0.5后,胶膜交联程度及各项性能下降。

A dual curing system for polyolefin elastomer （POE） encapsulation films was made up of a high activity peroxide and a low activity peroxide. DSC and FT-IR were used to analyze decomposition behavior of peroxide system in POE films. Combined with ts of crosslinking extent of cured films, the effects of the dual curing system on crosslinking behavior of POE and properties of cured films were investigated. It is found that, when peroxide is used solely, crosslinking extents in POE films follow this order： tert-butylper0xy 2-ethylhexyl carbonate （TBEC）/POE 〉 tert-amylperoxy 2-ethylhexyl carbonate （TAEC）/POE〉 〉 1, 1-di （ tert-butylperoxy）- 3, 3, 5- trimethylcyclohexane （BPMC）/POE, and all peroxides are decomposed partially during casting, process, leading to formatiori of microgels in uncured films. The crosslinking extent in the film cured with a dual curing system of TBEC and 2, 5-dimethyl-2, 5-di （t-butylperoxy）hexane （DBPH） is higher than that in the film cured with TBEC alone, when the mass ratio of TBEC/DBPH is higher. The light transmittance, tensile strength, peel strength and anti- aging property of the films cured with the dual curing system of TBEC and DBPH are all improved, and the formation of microgels in uncured films is suppressed with the dual curing system. However, when the mass ratio of TBEC/DBPH is less than 1.5/0.5, the crosslinking extent and other properties of the cured films drop.