Influence of nanoclay as a compatibilizer and a reinforcement for polymer blends used as insulators

Abstract

Polymer composite materials were prepared using kaolinite nanoclay as reinforcement in different weight fractions (3, 5 and 7) %, and blends of epoxy and polymethyl methacrylate (PMMA) as matrices. The current work aims to prepare a composite material with good thermal and acoustic insulation, besides improved mechanical properties, and the investigation of the effect of this nano additive on the compatibility between the two constituents of the blend, and how this compatibility might be beneficial to the performance of the prepared composite. The blend with an optimum mixing ratio (OMR) was chosen via impact test results; thus, the (80:20) percentage of epoxy and PMMA was chosen. The reinforced specimens showed an improvement in mechanical (impact and flexural) properties besides sound insulation and thermal conductivity, with the specimen reinforced with 7% nanoclay having the highest impact strength (97*10−3) KJ/m2 and the highest thermal conductivity value of (0.34) W/m.°C, with a sound intensity value 95.6 decibels at frequency 10,000 Hz. The scanning electron microscope images showed two separate phases in the unreinforced blend. In comparison, the 7% reinforced specimen showed a rough interface between the two polymer phases, suggesting a positive effect of nanoclay addition on compatibility. The differential scanning calorimeter showed two distinct glass transition temperatures for both reinforced and neat specimens, which belong to the glass transitions of both constituents (epoxy and PMMA). The main difference is the lower temperature gradient accompanied with the (nanoclay/blend) composite than the neat one. Although the blend remained immiscible, nanoclay had contributed to the compatibility and improved mechanical properties.