Effect of acetylated citrate plasticizer on mechanical properties of poly(vinyl chloride)

In this work, the effects of acetylation modification on the plasticization properties of citrates (triethyl citrate (TEC), acetyl triethyl citrate (ATEC), tributyl citrate (TBC) and acetyl tributyl citrate (ATBC)) were investigated by using a combination of characterization techniques and molecular dynamics (MD) simulation. The tensile test show that the acetylated ATEC and ATBC have better plasticizing efficiency compared to their non-acetylated counterparts, and consequently the tensile strength and elongation at break of ATEC/PVC (ATBC/PVC) are 13.9% (18.7%) and 8.3% (2.2%) higher than those of TEC/PVC (TBC/PVC), respectively. The MD simulation results corroborate these observations and further reveal the reason for these changes. The research mainly includes three aspects: 1. Effect mechanism of acetylation modification on the interaction between citrate and PVC; 2. The changes of microstructure, energy and motion state of PVC composites during tensile process; 3. Tensile failure mechanism of PVC composites under large tensile force. In addition, the effect of acetylation treatment on toxicity of citrate was also studied. Thus, our study contributes to better understanding of the plasticizing mechanisms of citrate and proposes an optimized citrate structure with higher performance.