ABSTRACT
Polymer dispersed liquid crystals (PDLCs) are a relatively new class of composite materials consisting of micrometric liquid crystalline droplets dispersed into a polymer matrix (Bronnikov et al. 2013). Thus, they combine the unique optical properties of liquid crystals (LCs) with the lm-forming ability and mechanical properties of a polymer matrix-resulting in appropriate materials for a large variety of exible opto-electronic applications (Bouteiller et al. 1996; Bronnikov et al. 2013; Dierking 2000; Drzaic 2006; Kitzerow 1994; Smith 1993). As evidenced by
7.1 Introduction .................................................................................................. 119 7.2 Obtaining Polymer Dispersed Liquid Crystals: Materials, Methods,
Advantages, and Disadvantages ................................................................... 120 7.3 Signicance of Experimental Methods in Polymer Dispersed Liquid
Crystal Characterization ............................................................................... 123 7.4 Polysulfone as Polymer Matrix for Polymer Dispersed Liquid Crystals
Addressed in Bio-Applications .....................................................................124 7.5 Chitosan-A Biopolymeric Matrix for Polymer Dispersed
Liquid Crystals ......................................................................................... 127 7.6 Polyvinyl Alcohol Boric Acid-A Matrix with High Liquid Crystal
Anchoring Power .......................................................................................... 130 7.6.1 Polymer Dispersed Liquid Crystal Composites Based on
Polyvinyl Alcohol Boric Acid Matrix and 5CB Nematogen ............ 130 7.6.2 Polymer Dispersed Liquid Crystal Films Based on
Polyvinyl Alcohol Boric Acid Carrying Matrix and a Smectic Liquid Crystal ..................................................................132
7.7 Remarks ........................................................................................................ 135 Acknowledgments .................................................................................................. 135 References .............................................................................................................. 135
Fergason in 1984 (Fergason 1985), the development of PDLC composites started once their potential as active substrate in displays had been determined (Drzaic 2006). Applications as smart windows, holographic systems, microlenses, or lasers kept researchers interest in this challenging domain that grew constantly (Bouteiller et al. 1996; Bronnikov et al. 2013; Dierking 2000; Drzaic 2006; Kitzerow 1994; Smith 1993). Recent years have brought new achievements in this area, such as the use of PDLCs for bio-applications-for example, smart food packaging (Perju et al. 2011, 2015), tunable articial iris modulating light intensity through human eyes for assisting patients of aniridia (Hsu et al. 2011; Lapointe et al. 2010), bio-sensors for biologically active matter (Sidiq et al. 2014), or other envisaged bio-applications (Woltman et al. 2007). Such innovative bio-applications use biocompatible materials. To apply PDLC systems as the next generation of biomaterials addressed in biotechnology and medicine, friendly soft composites based on biocompatible polymers need to be developed. This is the reason why the ability of biopolymers or biocompatible polymers to act as polymer matrices for PDLC composites is currently of interest.
