环保增塑剂环己烷1,2-二甲酸二(2-丙基庚)酯的合成及性能

Preparation and Evaluation of the Environment-Friendly Plasticizer Di( 2-propylheptyl)-1,2-cyclohexane Dicarboxylate

以六氢苯酐和2-丙基庚醇为原料,钛酸四丁酯为催化剂,进行酯化反应得到环己烷1,2-二甲酸二(2-丙基庚)酯(DPHCH)增塑剂。考察了醇酸摩尔比、催化剂种类及用量、反应温度、反应时间对酯化率的影响。确定了最佳工艺条件为:醇酸摩尔比为2.8∶1,反应温度为200℃,反应时间为3 h,催化剂用量为六氢苯酐质量的1.5%。产品为无色透明油状液体,酯化率可达到99.49%。采用傅里叶变换红外光谱(FTIR)及核磁共振氢谱(1HNMR)对DPHCH结构进行表征,将DPHCH作为增塑剂制成聚氯乙烯(PVC)树脂,并进行了拉伸性能、挥发减量、热重分析,结果表明,与增塑剂DINCH、DEHCH和DOP相比,DPHCH具有优异的增塑性能及热稳定性能。

Di（ 2-propylheptyl）-1,2-cyclohexane dicarboxylate（ DPHCH） was synthesized via esterification of hexahydrophthalic anhydride（ HHPA） with 2-propylheptanol by using tetrabutyl titanate as a catalyst. The effects of reaction parameters on the esterification were studied by investigating the temperature,reaction time,molar ratio of 2-propylheptanol to HHPA,and catalyst content. The experimental results confirmed the optimum reaction conditions of esterification as follows：the molar ratio of 2-propylheptanol to HHPA was 2. 8 ∶ 1,the reaction temperature was 200 ℃,the reaction time was 3 h,and the amount of catalyst was 1. 5%（ based on the mass of acid）. The esterification yield under such conditions was 99. 49% and a colorless transparent oily liquid was obtained. Functional group analysis was conducted by means of FTIR and1 HNMR spectroscopy. The weight loss on heating and TG were measured. PVC compounds after addition of the synthesized plasticizer DPHCH presented similar plasticizing performance with DEHCH,DOP and DINCH,as is demonstrated by comparisons of the results of mechanical properties,weight loss on heating and TG tests obtained for plasticized PVC compounds,indicating its great value in industrial application