Polymer mica : layered polymer with nanometer sized interlayer gaps

摘要

The unique stacked-layers structure of naturally occurring mineral mica is largely responsible for its good thermal and electrical properties. We have been able to create a corresponding structure in polymers with similar results. Layered polymers with nanometer sized interlayer gaps filled with gas have been produced such that the energy transfer between the polymer layers has to occur through the intervening gas layer, thereby giving this morphology superior insulation properties. The insulation efficiency of layered polymers is much higher than that of polymer foams whose properties are density dependent. The layered structure is achieved by first making a template containing regions of weak chain-entanglements and then severing these entanglements by gas nucleation and expansion. A typical morphology consists of stacked polymer layers, around 10 \u3bcm thick, and the interlayer gaps, about a few nanometer thick. It is similar in appearance to mica, but can be produced in a controlled way. Here we present the technique for producing the multilayered polymer, and the unique properties associated with such structures.