Chinese Journal of POLYMER SCIENCE ARTICLE

https://doi.org/10.1007/s10118-018-2055-5 Chinese J. Polym. Sci. 2018, 36, 214−221

Synthesis of High Performance Cyclic Olefin Polymers Using Highly

Efficient WCl6-based Catalyst System

Yi-Ran Zhanga, Ji-Xing Yanga, Li Pana*, and Yue-Sheng Lia, b a Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300350, China b Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China

◆EE ElectronicA Supplementary Information

Abstract Cyclic olefin polymers (COPs) with high temperature, high transparency (higher than 80%) in the visible light range, excellent thermal stability and outstanding mechanical properties have been synthesized by effective ring opening metathesis polymerization (ROMP) of exo-1,4,4a,9,9a,10-hexahydro-9,10(1′,2′)-benzeno-l,4-methanoanthracene (HBM) and dicyclopentadiene (DCPD) or (NBE) using WCl6/i-Bu3Al/ethanol/1-hexene catalyst system, followed by hydrogenation of double bonds. 1-Hexene acted as a molecular weight controller in the polymerization reaction, tuning the number-average molecular weight (Mn) of P-HBM from 5.8 × 104 to 41.1 × 104. The monomer composition and thermal properties of the copolymers were characterized by nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The saturated polymers exhibited high decomposition temperatures (Td) around 340 °C and glass transition temperatures (Tg) in the range from 117.5 °C to 219.7 °C. What is more, tensile tests indicated that the mechanical properties of the COPs could be effectively tuned in a wide range by introducing varying amount of small cyclic olefin such as DCPD or NBE.

Keywords Ring-opening metathesis polymerization; Hydrogenation; Cyclic olefin polymers; Glass transition temperature; Mechanical properties

Citation: Zhang, Y. R.; Yang, J. X.; Pan, L.; Li, Y. S. Synthesis of High Performance Cyclic Olefin Polymers Using Highly Efficient WCl6-based Catalyst System. Chinese J. Polym. Sci. 2018, 36(2), 214−221.

[15, 16] INTRODUCTION service temperature range . The Tgs of the main-stream products are in the range of 130−160 °C. Besides, toughness Over the past years, cyclic olefin copolymers (COCs) and is another important parameter of COC or COP products. cyclic olefin polymers (COPs), as a kind of high value-added However, most of the commercial products with high Tg thermoplastic engineering plastics made by usually show very poor toughness. For example, commercial (co)polymerization of cyclic olefin, have attracted extensive ® TOPAS 6017 with high Tg of 180 °C has very low attention from both academic and industry researchers elongation (< 3%), whereas, the COPs of Zeones® such as because of their excellent properties such as excellent 480R with improved ductility (elongation = 40%) shows low transparency, low moisture absorption, low birefringence, Tg (140 °C). Therefore, there is a strong desire to synthesize low density, good chemical resistance, excellent thermal high-performance COCs and COPs with both improved stability and etc[1−4]. The promising COCs and COPs can be toughness and high Tg. For COCs, increasing the cycloolefin widely used in the field of drug packaging, digital cameras, content[17, 18] and employing bulkier cycloolefin[15, 19−21] are optical recordings and electrical insulation, and they are two effective ways to enhance the Tg value. However, high showing very good prospects. COCs and COPs are cycloolefin content always results in increased brittleness. synthesized in different ways. COCs are usually obtained by Taking copolymer of norbornene (NBE) and as a the addition copolymerization of cycloolefin with ethylene [5−10] typical example, it