Cyclic Olefin Terpolymers with High Refractive Index and High Optical Transparency

Abstract

Cyclic olefin copolymer (COC) is one of the most promising optical materials; however, the brittle COC suffers from issues including a low refractive index. In this contribution, by the introduction of high refractive index comonomers including phenoxy substituted α-olefin (C 4 OAr), p-tolylthio substituted α-olefin (C 4 SAr) and carbazolyl substituted α-olefins (C 4 NAr, C 3 NAr, and C 2 NAr), the zirconocene mediated terpolymerization of ethylene (E) and tetracyclododecene (TCD) produces the preferred E-TCD-C n NAr (n = 2, 3, and 4) cyclic olefin terpolymers (COT) with tunable compositions (TCD: 11.5-35.8 mol %, C n NAr: 1.2− 5.0 mol %), high molecular weights and high glass transition temperatures (up to 167 °C) in high catalytic activities. Compared to the E-TCD copolymer (COC) material, these COT materials show the comparable thermal decomposition temperature (T d,5% = 437 °C), slightly higher strain at break value (up to 7.4%) and higher tensile strength (up to 60.5 MPa). In particular, these noncrystalline optical COT materials have significantly higher refractive indices of 1.550−1.569 and are more transparent (transmittance: 93−95%), relative to the COC materials, indicative of an excellent optical material.

Dinuclear Half-Titanocene Complex Bearing an Anthracene-Bridged Bifunctional Alkoxide Ligand: Unprecedented Cooperativity toward Copolymerization of Ethylene with 1-Octene or Norbornene

“…The latter leads to production of COCs, which are attractive engineering plastics with high performances, including high transparency in the ultraviolet–visible (UV–vis) region (amorphous material), good thermal resistance (high T g ), and extremely low water absorption (excellent water vapor barrier properties) . Many catalytic systems, such as conventional metallocene, − constrained geometry catalyst (CGC), , nonbridged half-titanocene, and nonmetallocene, , have been reported for the copolymerization of ethylene with cyclic olefins, especially with norbornene (NBE). However, successful catalysts that can produce COCs with random structures, high molecular weights ( M w s), narrow distributions, and high T g values (high NBE contents) are still limited …”

High Refractive Index and High Abbe Number Polymer Based on Norbornadiene

“…Importantly, the resulting polymer has a surprising Abbe number, which is the highest reported in recent years. As shown in Figure c, the high- v (>30) materials and commercial products (PMMA, PC, CR-39, COC, and MR-8) in recent years are compared. ,,,,− ,, P­(DMMD-P) and P­(DEMD-P) are in the yellow area above the middle, which achieves an Abbe number of 59 while maintaining a refractive index of 1.60. This is because the special heterocycle structure of the monomer and the ester bond in the polythiols endow the material with an extremely high Abbe number.…”

“…Although the mentioned sulfur-containing polymers can easily achieve a high- n above 1.60, the abundant aromatic rings in the molecular structure also bring high atomic dispersion (Δ R ), thus exhibiting a relatively low Abbe number (less than 50). − Recent studies have shown that cyclic olefins and sulfur-containing alicyclic groups have a lower Δ R than aliphatic groups . In particular, the cyclic olefin copolymers (COCs) prepared from norbornene have developed rapidly in the past decade, which have a high- v and high optical transparency. − However, the disadvantage of COC materials is that the n value is relatively low (1.52–1.54) and it is difficult to regulate to achieve enhancement. − Similarly, norbornadiene has great potential in endowing sulfur polymers with interesting optical and mechanical properties owing to the inherent bearing of the unique aliphatic rigid structure. − Hence, based on the excellent optical properties of norbornene, the design of optical materials with high- n and high- v has important research significance and great commercial value.…”

High Compression Strength and Thermal Insulation Silica Aerogel Monolith with Scaffold of a Cyclic Olefin Siloxane Co-Oligomer via Ambient Pressure Drying

“…Therefore, combining a polymer of high mechanical strength with a silica framework can potentially achieve reinforcement with minimal impact on the size and stacking of secondary particles. Cyclic olefin copolymers are particularly noteworthy for their high mechanical strength and modulus. − The copolymerization of norbornene and ethylene with 46.5 mol % of cyclic olefin yields a brittle material with a remarkable tensile strength of 47.8 MPa and compressive modulus of 2580 MPa …”