Thermally conductive and electrically insulative polypropylene composites based on polymethylsilsesquioxane...

Area of Science:

• Materials Science
• Polymer Science
• Composite Materials

Background:

• Polypropylene (PP) is a versatile thermoplastic polymer.
• Enhancing PP properties is crucial for advanced applications.
• Polymethylsilsesquioxane (PMSQ) is a potential reinforcing agent.

Purpose of the Study:

• To investigate the impact of PMSQ microparticles on PP composite properties.
• To evaluate thermal, thermo-mechanical, and electrical characteristics.
• To determine optimal PMSQ concentrations for desired property enhancements.

Main Methods:

• Polypropylene (PP) and polymethylsilsesquioxane (PMSQ) microparticles were melt-blended at varying concentrations (0-15 wt%).
• Differential scanning calorimetry (DSC) analyzed thermal transitions.
• Thermogravimetric analysis (TGA) assessed thermal stability.
• Dynamic mechanical analysis (DMA) evaluated thermo-mechanical behavior.
• Thermal conductivity and electrical resistivity were measured.

Main Results:

• Slight alterations in PP's melting and crystallization temperatures were observed.
• Thermal stability significantly improved with increasing PMSQ content.
• Storage modulus increased by 32% at 15 wt% PMSQ, indicating enhanced stiffness.
• Thermal conductivity improved by 20% with 10 wt% PMSQ.
• Electrical resistivity increased tenfold, signifying improved insulation.

Conclusions:

• PP/PMSQ composites exhibit enhanced thermal stability and mechanical stiffness.
• Incorporation of PMSQ improves thermal conductivity while significantly boosting electrical resistivity.
• These composites are suitable for applications demanding efficient heat management and electrical insulation, such as in electronics.