Polyvinyl Alcohol Based Polarizer for New Displays: Molecule, Processing and Properties

Abstract

Polarizers are the key components of new display panels (i.e. Liquid Crystal Display, LCD, Organic Light-Emitting Diode,OLED) , consisting of polarizing film, support film, compensation film, and optical clear adhesives between the layers. The key functional layer is the iodine-doped polyvinyl alcohol (PVA) film. The processing of polarizer involves the synthesis of optical-grade PVA resin and the preparation of highly oriented iodine doped PVA film, which includes film casting, iodine doping, boric acid crosslinking, and post-stretching. Revealing the multi-scale structure and chain dynamics change during processing is crucial for establishing the structre-process-property relationship of PVA based polarizer. Current work reviews recent research progresses in this direction, primarily including: 1) primary chemcial structure of PVA, 2) solution casting of PVA Films, 3) hierarchical structure and dynamics heterogeneity of plasticized PVA Films, 4) formation mechanism of PVA-Iodine complex, and 5) crosslinking mechanism of boric acid in PVA