Synthesis, performance evaluation, and plasticization dynamics of biobased vanillic acid plasticizer for poly(vinyl chloride)

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 497; p. 154991
• Main Authors: Qian, Bingfeng, Shen, Fang, Zhu, Huichao, Zhang, Jianan, Wu, Mingyuan, Liu, Jiuyi, Wu, Qingyun, Yang, Jianjun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2024
• Subjects: Density functional theory calculations; Glass transition temperature; Molecular docking simulation; Nontoxic plasticizer; Vanillic acid; Vanillic acid; Nontoxic plasticizer; Molecular docking simulation; Glass transition temperature; Density functional theory calculations
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.154991

[Display omitted] •Ether bond helps VAE improve the plasticizing effect of PVC by 12 times.•VAE has better plasticizing performance than commercial plasticizers.•Ether groups in VAE enhance PVC’s miscibility and mechanical properties.•VAE exhibited safety characteristics in toxicity assessment. Phthalate-based plasticizers are widely used to improve the flexibility and ductility of engineering plastics. However, their hazardous toxicity and unsustainability have prompted the plastics industry to develop safe and efficient green plasticizers. Therefore, it is imperative to develop safe biobased plasticizers from renewable resources. The ether group had been introduced into renewable vanillic acid to synthesize vanillic acid ester derivatives (VAE) using a clean method, and characterized using various spectral methods. The application performances were compared for VAE and three commercial plasticizers for poly(vinyl chloride) (PVC) plasticization. Dynamic mechanical analysis (DMA) indicated that the presence of VAE could reduce the glass transition temperature of PVC by over 50 %, which is 32 % lower than induced by the dioctyl phthalate. The presence of carbonyl and ether groups in VAE increases the elongation at break of PVC by more than 12 times, and the elongation at break (419.8 %) is 10 % higher than that of acetyl tributyl citrate plasticized PVC. Thermogravimetric analysis and aging experiments indicated that PVC blend plasticized by VAE exhibited superior thermal stability compared to acetyl tributyl citrate. The interaction between PVC and the carbonyl and ether groups in VAE has been demonstrated through multifaceted analysis utilizing density functional theory calculations. The binding energy between fragments was −17.8 kcal/mol, and the interaction was visualized by IGMH. Under this interaction, VAE exhibited extremely low migration in PVC blends. Acute oral toxicity tests were used to demonstrate that VAE is harmless to rats even at high doses. Overall, VAE, as a sustainable, low-risk, and efficient PVC plasticizer, outperforms typical commercial plasticizers and is a promising alternative to phthalates.