Systematic Control of Sulfur Chain Length of High Refractive Index, Transparent Sulfur-Containing Polymers with Enhanced Thermal Stability

Abstract

We herein report the preparation of high refractive index polymers (HRIPs) with enhanced thermal stability from the copolymerization of S 8 and divinylbenzene (DVB) in a single step through sulfur chemical vapor deposition (sCVD). Varying the process temperature in sCVD allowed for the preparation of a series of high sulfur content polymers which, in comparison to previously reported sulfur-derived polymers with similar compositions, displayed significantly enhanced solvent resistance, glass transition temperature (T g ), and thermal stability attributed to the absence of long polysulfide chains in the polymer matrix. The resulting HRIP films displayed high transmittance over the entire visible range while showing an unprecedentedly high T g of 110 °C, which is one of the highest to date among HRIPs with refractive index (RI) exceeding 1.8 reported to date. With the combination of ultrahigh (>1.8) RI, thermal stability, and high T g , the HRIPs can serve as compelling materials for advanced optical applications.

Determining the Local Refractive Index of Single Particles by Optical Imaging Technique

“…The BF image of separated particles and in-situ SEM image shows the uniformity of spherical shape and particle size (Figures A and B). In Figure C, the accurate refractive index of RI standard solutions is measured by a commercial Abbe refractometer at 293 K. The linear refractive index distribution of 16 RI standard solutions is presented in Figure D, which is calculated by the Lorentz–Lorenz equation: − where n mix is the refractive index of the liquid mixture with different volume ratios, and n 1 , n 2 , and n 3 are the RIs of 1BrN, DMF, and DIW measured by the Abbe refractometer at 293 K. The parameters φ 1 , φ 2 , and φ 3 are volume fractions of three solution components, respectively. For these homogeneous particles, the BF intensity in the series of standard solutions are plotted and extracted using the respective RI at the single-particle level (Figures E and F).…”

Visible, Mid- and Long-Wave Infrared Transparent Sulfur-Rich Polymer with Enhanced Thermal Stability

“…No apparent loss of pSHVDS film thickness was observed (Figure 3c), confirming the exceptional thermal stability of pSHVDS 170 compared to previously reported HSCPs. 24,28 Despite the trade-off between the sulfur content and T g commonly observed in HSCPs, pSHVDS 170 exhibited an unprecedented combination of high thermal stability and high sulfur content (Figure 3d).…”

Anionic Hybrid Copolymerization of Sulfur with Acrylate: Strategy for Synthesis of High-Performance Sulfur-Based Polymers

“…Although it has certain applications in rubber vulcanization and additives, it is still excessive. The petrochemical industry alone generates more than 70 million tons of S 8 as a byproduct every year. , Developing sulfur-containing polymer materials provides a route to utilize S 8 . − For this purpose, S 8 was employed to directly react with diamines, aryl halides, or vinyl comonomers. − Also, it was used in multicomponent polymerization with diacids and diamines, or diisocyanides and diamines, etc. − …”