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Abstract Due to their wide range of applications and their complex material properties, it is desirable to be able to predict the behaviour of injection moulded parts with the help of simulation tools. For semi-crystalline materials, this can only take place with considerable accuracy if the inhomogeneous material properties are taken into account. Because of this, it is necessary to calculate the microstructure of the solidified melt and to incorporate these findings in the simulation. We present an integrative, multiscale simulation approach in which the manufacturing process is calculated on a macroscale and the solidification process on a mesoscale. A multiphase filling and cooling simulation is done to calculate temperature and velocity fields, which are used as boundary conditions for the calculation of the spherulite distribution in the part. We present the used nucleation and growth model and shortly describe the parallelisation approach of the mesoscale simulation.

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Environmental stress cracking (ESC) is a premature failure of a polymer exposed to a fluid, under stress which is much less than its yield stress. Many experimental works were done before in an effort to predict experimentally the ESC potential of a fluid in different polymers. None of the previous works applied molecular modeling techniques to predict this potential so this work is a pioneering work. This study's goal was to apply atomistic molecular modeling techniques to gain a better understanding of the ESC mechanism and to predict the ESC potential of different fluids in polymers. Our model experimental system was amorphous polycarbonate (PC) with water as an ESC fluid. The computational study was expanded to include a high level ESC fluid for PC-toluene and a non ESC fluid-BD, together with the moderate ESC fluid-water. A clear distinction between ESC fluids and non ESC fluids for PC was achieved by means of molecular modeling. The experimental work approved that water is an ESC fluid for PC as predicted in the computational part.