对羟基肉桂酸酯类增塑剂烷基链长度变化对PVC增塑性能的影响

Influence of Alkyl Chain Length of Plasiticizers from p-Coumaric Acid on the Plasticization Properties of PVC

以来源于可再生资源的对羟基肉桂酸为原料合成了一系列生物基增塑剂,研究了此类增塑剂烷基链长度变化对聚氯乙烯(PVC)的增塑效率、热稳定性和耐久性的影响。当对羟基肉桂酸酯类增塑剂左侧烷基碳链由9个缩短为3个,增塑PVC的玻璃化转变温度由28.7℃下降到19.0℃,断裂伸长率则由194.7%增加到237.0%。因此,缩短此类增塑剂烷基链长度可以有效地提高其增塑效率。然而,缩短增塑剂烷基链长度会导致其相对分子量降低,最终会使增塑PVC的热稳定性和耐久性变差。此外,对羟基肉桂酸酯类增塑剂的综合性能可与邻苯二甲酸二辛酯(DOP)相媲美,具有替代此类石油基增塑剂的潜力。

A series of bio-based plasticizers were synthesized by using renewable p-coumaric acid as the raw material.The influence of various alkyl chain length of the synthesized plasticizers on the plasticizing efficiency,thermal stability and durability of polyvinyl chloride(PVC)was also studied.When the length of alkyl carbon chain on the left of the synthesized plasticizer shortened from nine to three,the glass transition temperature of corresponding plasticized PVC reduced from 28.7℃to 19.0℃,and the elongation at break increased from 194.7%to 237.0%.Therefore,shortening the alkyl chain length of the synthesized plasticizer could improve its plasticizing efficiency obviously,however,it would reduce the relative molecular weight,which finally endowed the plasticized PVC with a poorer thermal stability and durability.In addition,the comprehensive properties of p-hydroxycinnamate plasticizers are comparable to that of dioctyl phthalate(DOP),which have the potential to replace such petroleum based plasticizers.