Hybrid acrylic–polyimide latexes from miniemulsion polymerisation

Abstract

Abstract A rigid polyimide (PI) was dissolved in acrylic monomers (methyl methacrylate, n‐butyl acrylate) as a hydrophobe to form miniemulsions stabilized by a mixture of sodium dodecyl sulfate and Triton ® , with droplets size in the range 100–300 nm, and PI concentration up to about 30% by weight, which corresponds to its limit of solubility. Upon polymerization initiated with ammonium persulfate, the particle size tends to decrease to the range 80–250 nm. From these hybrid latexes, clear yellowish films were obtained with two glass transitions: one close to that of polybutylacrylate ( T g = −50 °C) and the second between 15 and 40 °C, depending on PI concentration. PI causes a reinforcement of the mechanical properties at room temperature. This reinforcement is enhanced through an appropriate thermal treatment. Copyright © 2004 Society of Chemical Industry