Modifying Thermal Expansion of Polymer Composites by Blending with a Negative Thermal Expansion Material

Abstract Large positive thermal expansion in polymers is one of the major drawbacks in using polymers in applications where the sample dimensions play an important role. In this paper, we report a method to vary the thermal expansion of PMMA‐based polymer composites by blending with a negative thermal expansion material, PbTiO 3 . It is shown that the thermal expansion coefficient of the composite can be tailored by suitably adjusting the ratio of polymer and ceramic filler. The coefficient of thermal expansion has been measured using temperature‐dependent step‐height measurements via confocal microscopy. Using SEM, it is shown that the ceramic particles are homogeneously dispersed in the polymer matrix if the composite is obtained by the polymerization of the suspension of PbTiO 3 in the monomer MMA. Composite formation is confirmed using XRD and Raman spectroscopy. To estimate the technological viability of such composite films, preliminary results of stress‐strain measurements are also presented. magnified image