Effect of a Polymercaptan Material on the Electro-Optical Properties of Polymer-Dispersed Liquid Crystal Films

• Main Authors: Yujian Sun, Cuihong Zhang, Le Zhou, Hua Fang, Jianhua Huang, Haipeng Ma, Yi Zhang, Jie Yang, Lan-Ying Zhang, Ping Song, Yanzi Gao, Jiumei Xiao, Fasheng Li, Kexuan Li
• Format: Article
• Language: English
• Published: MDPI AG 2016-12-01
• Series: Molecules
• Subjects: polymer-dispersed liquid crystal; morphology; electro-optical properties; photopolymerization
• Online Access: http://www.mdpi.com/1420-3049/22/1/43

Polymer-dispersed liquid crystal (PDLC) films were prepared by the ultraviolet-light-induced polymerization of photopolymerizable monomers in nematic liquid crystal/chiral dopant/thiol-acrylate reaction monomer composites. The effects of the chiral dopant and crosslinking agents on the electro-optical properties of the PDLC films were systematically investigate. While added the chiral dopant S811 into the PDLC films, the initial off-state transmittance of the films was decreased. It was found that the weight ratio among acrylate monomers, thiol monomer PETMP and the polymercaptan Capcure 3-800 showed great influence on the properties of the fabricated PDLC films because of the existence of competition between thiol-acrylate reaction and acrylate monomer polymerization reaction. While adding polymercaptans curing agent Capcure 3-800 with appropriate concentration into the PDLC system, lower driven voltage and higher contrast ratio were achieved. This made the polymer network and electro-optical properties of the PDLC films easily tunable by the introduction of the thiol monomers.