Shear and cooling induced regulation of mechanical properties and glass transition temperature of isotactic polypropylene

Abstract

In different experimental studies, it has been observed that polymer properties such as structural, mechanical and thermo-mechanical properties vary with processing conditions. Therefore, molecular dynamic simulation techniques are used to investigate the variation in mechanical and physical properties of isotactic polypropylene polymer under various processing conditions. Non-equilibrium molecular dynamics simulation was used to look into the effect of shear rate on properties. Further different cooling rates were used to cool down the melt structures. For different shear and cooling rates, we calculated selected structural, mechanical and physical properties of polymer which include density of polypropylene in solid state, Young’s modulus and glass transition temperature respectively. Young’s modulus and glass transition temperature show dependency on shear and cooling rate. Results showed that high shear and slow cooling significantly enhance the Young’s modulus and glass transition temperature of the processed polymer.