新型栲胶聚丙氧基醚酯的合成及增塑PVC性能

Manufacturing of tannin polypropoxy ether carboxylates as efficient and improved migration resistance plasticizers for PVC

以工业级杨梅栲胶粗品为原料,通过环氧丙烷醚化和脂肪酸(乙酸、丁酸和油酸)直接酯化的方式,构建增塑性能高、抗迁移性能好的栲胶聚丙氧基醚酯增塑剂(TEPEA、TEPEB和TEPEO)。利用凝胶渗透色谱仪、核磁共振氢谱、傅里叶变换红外光谱对栲胶聚丙氧基多元醇和栲胶聚丙氧基醚酯的分子量和结构进行表征,并对栲胶聚丙氧基醚酯增塑剂增塑后聚氯乙烯(PVC)制品(PVC/TEPEA、PVC/TEPEB和PVC/TEPEO)的表观形貌、力学性能、耐低温性能、耐挥发性能和耐溶剂迁移性能进行测试。此外,通过合成低分子量栲胶聚丙氧基乙酸酯(LTEPEA),并将其增塑后的PVC制品(PVC/LTEPEA)与PVC/TEPEA、PVC/TEPEB和PVC/TEPEO进行综合性能差异比较,研究丙氧基对栲胶基增塑剂综合性能的影响。结果表明,栲胶聚丙氧基醚酯增塑后PVC制品的综合性能与其结构中丙氧基聚合度及酯基上的烷基碳链长度有关;丙氧基聚合度大且酯基上碳链最短的栲胶聚丙氧基乙酯(TEPEA)增塑后的PVC制品的增塑、耐挥发和抗迁移性能均优于传统石油基邻苯二甲酸二辛酯(DOP)增塑后的PVC制品(PVC/DOP),表明TEPEA可作为主增塑剂替代有毒的DOP。

Novel tannin polypropoxy ether carboxylates(TEPEC)equipped with excellent plasticization and migration resistances for PVC resin were synthesized through the propoxylation of tannin extracts derived from waste bark and then esterification with fatty acid(acetic acid,butyric acid,and oleic acid).Then the structures of tannin-based polypropoxy polyol and its esters(TEPEA,TEPEB and TEPEO)were confirmed by GPC,1H NMR and FTIR.The performances including surface morphology,tensile property,low temperature resistance and volatility resistance,as well as migration resistances of PVC samples plasticized by tannin polypropoxy ether carboxylates(PVC/TEPEA,PVC/TEPEB and PVC/TEPEO)were systematically investigated and respectively compared with that of neat PVC and PVC blended with dioctyl phthalate(PVC/DOP).Additionally,low molecular weight tannin polypropoxy ether acetate(LTEPEA)was also synthesized and used as a reference to evaluate the effect of propoxy unit on the properties of PVC samples plasticized by tannin polypropoxy ether carboxylates.The results indicated that the overall performances of PVC samples plasticized by tannin polypropoxy ether carboxylates were dependent on their structures,where the performances of PVC plasticized by tannin polypropoxy ether carboxylates holding largest propoxy units and shortest methyl group(PVC/TEPEA)were better than PVC samples blended with others plasticizers(PVC/TEPEB,PVC/TEPEO and PVC/DOP).All of the results suggested that tannin polypropoxy ether acetate(TEPEA)had a great potential to totally the traditional petro-based DOP applied in PVC industry.