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Films were made by incorporating various quantities of fluoroalkyl acrylate (FA) into the chain termini of polyurethane acrylate oligomer of polymer stabilized cholesteric liquid crystals (PSCLCs). The effects of switching voltage, scanning electron and polarized optical microscope morphologies, texture transition and reversibility, and contact angle of the films were then studied. It was found that the switching voltage of the film decreased with the addition of FA up to 0.8 wt%, beyond which it increased. The decrease and increase were respectively explained in terms of decreased interface energy as noted from the contact angle of the LC on polymer surface, and too small droplet size as noted from the SEM. Copyright © 2008 John Wiley & Sons, Ltd.

Rheological, thermal, and mechanical properties of polypropylene homo polymer (PPH)/amorphous poly alpha olefin (APAO) blends as a function of molecular weight, comonomer type and content, and blend composition have been investigated. Homo APAO grade showed better compatibility than copolymerized ones in terms of rheological and thermal properties. The mechanical strength showed strong dependence on APAO content and type, and the impact strength and melt index rapidly increased for certain types of APAO at and above 30 wt%. On comparison with commercially used PPH/ethylene–propylene rubber (EPR) blend system, it is supposed that PPH/APAO blend can be successfully used in thermoplastic polyolefin applications. Copyright © 2007 John Wiley & Sons, Ltd.

The interposition of surfactants between polymer and liquid crystal (LC) droplets was theoretically predicted by the positive spreading coefficient (0