Thermal conductivity of AlN/polystyrene interpenetrating networks

A new processing technique is proposed for preparing AlN/polystyrene interp enetrating network composites. This technique is based on an infiltration p rocedure, partly conducted in vacuo, of a liquid mixture of monomer and ini tiator into a porous AlN ceramic body with a percolated pore structure. Suc cessive in situ polymerization is produced by heating up the infiltrated ce ramic at approximate to 100 degrees C under ambient pressure. The final mor phology of the composite consists of an interpenetrating polymer network wh ich fills in an AlN ceramic skeleton. This new infiltration procedure enabl ed us to prepare continuous polymeric networks whose volume fraction lies b etween approximate to 12 and 40 vol%. These fractions of polymer are consis tently lower than that usually involved in traditional polymer moulding pro cesses. It is shown both by experiments and theory that these special inter penetrating network microstructures experience relatively high thermal cond uctivity. Concurrently, significantly improved fracture characteristics and reliability can be achieved as compared with both that of monolithic ceram ics and traditional polymeric materials containing high fractions of cerami c filler. (C) 2000 Elsevier Science Ltd. All rights reserved.