Chemical Research in Chinese Universities ›› 2025, Vol. 41 ›› Issue (4): 910-918.doi: 10.1007/s40242-025-5030-z

• Articles • Previous Articles     Next Articles

Preparation of High-quality Terpene Resin in Acidic Deep Eutectic Solvent

WANG Mengye, YUAN Bing YU Fengli   

  1. State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P. R. China
  • Received:2025-02-21 Accepted:2025-05-12 Online:2025-08-01 Published:2025-07-24
  • Supported by:
    This work was supported by the National Natural Science Foundation of China (No. 32371820).

Abstract: Lewis acid-based deep eutectic solvents (DESs) were applied for catalyzing the polymerization of β-pinene to obtain high-quality terpene resin for the first time. Structural characterization of DESs, combined with density functional theory (DFT) calculations, verified that hydrogen bonds and covalent bonds drive DES formation. The DES prepared by the self-assembly of AlCl3 and acetamide (ACA),[AlCl3]3[ACA]2, showed the best catalytic performance. Under the optimized reaction conditions (10 g of β-pinene, 3 g of DES catalyst, reaction temperature 0℃, and reaction time 4 h), the softening point of the obtained terpene resin was as high as 142.0℃ (global method), and the terpene resin yield reached 94.2%. After the reaction, the DES and product showed good separation, which is conducive to the recovery and reuse of the DES. The quality of the terpene resin satisfied the T-110 standard after four cycles. The structure of the terpene resin was characterized using Fourier-transform infrared (FTIR) and 1H nuclear magnetic resonance (NMR) spectroscopy. The number molecular weight (Mn) of the terpene resin determined by gel permeation chromatography (GPC) was 4055, and thermogravimetric (TG) analysis showed that the terpene resin was stable below 300℃.

Key words: Deep eutectic solvent, Terpene resin, β-Pinene, Polymerization, Polymer