New polymer to enhance the permanent memory effect of polymer dispersed liquid crystal films

Conventional polymer dispersed liquid crystals (PDLC) are devices with recognized applications. New PDLCs with permanent memory effect (PME) can be used as digital memory devices. The synthesis and characterization of a new monomer [pentaerythritoltetramethacrylate (PE4MA)] is here described. A PDLC was produced using the synthesized monomer (PE4MA) copolymerized with commercially available monomethacrylate oligomer poly(propyleneglycol) methacrylate (PPGMA) and 70% (w/w) liquid crystal (E7), showing 98% permanent memory effect, with 72% memory state contrast (MSC) and an electric field required to achieve 90% of the maximum transmittance (E-90) of 3 V mu m(-1). The synthesized monomer (PE4MA) copolymerized with PPGMA seems to be a prospective material for preparation of PDLC with permanent memory effect with a view to application for digital memory devices based on write-read-erase cycles. (c) 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43482.