Monodisperse latex with variable glass transition temperature and particle size for use as matrix starting material for conductive polymer composites

A series of surfactant-free monodisperse latices were prepared with varying glass transition temperatures (T,) and particle sizes using methyl methacrylate (MMA) and butyl acrylate (BA) monomers. Latices with T(g)s between -11 and 105 degreesC were synthesized by varying the MMA to BA ratio during batch polymerization. The particle size of latices with a T-g of 19 degreesC was varied by independently changing temperature, initiator concentration and ionic strength of the aqueous reaction medium. These latices provide a model matrix starting material for carbon black-filled electrically conductive polymer composites. When latex with a number average particle diameter (D,) of 930 mm is substituted for a solution-based polymer the percolation threshold of the final conductive composite drops from 14.5 to 1.45 vol% carbon black. (C) 2001 Elsevier Science Ltd. All rights reserved.