In modern world there is a tendency to miniaturize electronic devises, to do so a new materials with dedicated physical properties are needed. When we look on overall materials used in microelectronic, majority of them are polymers. It is due to the fact that there is a big variety of them and mixing them could change their physical properties significantly. On the other hand new products require shorter time-to-market. This induces a need for shorten R&D process. Experimental research is time and money consuming. Using Advanced Computer Techniques it is possible to shorten R&D time for example by running parallel simulations. It is obvious that in a selected group of materials with the best properties, it is necessary to conduct experimental validation of them. As the computer simulation only gives a tendency or trend rather than exact numerous values. Molecular modeling is such tool that provides a possibility of extracting properties of polymers materials. In this pa per the authors focused on crosslinked polymers used as moulding compounds in electronic packaging. The knowledge on thermo-mechanical properties of molding compounds is essential in order to provide reliability of the microelectronic devices on satisfactory level. The model of commonly used polymer as moulding compound was created, in previous works authors used 100% crosslink model. Authors with the awareness that in the real world so high conversion rate is never achieved introduces partially conversed model. Although the simulation in nano-scale are more accurate but they need significantly more CPU power, for this reason the authors as an alternative also introduced modeling in meso-scale. The results are promising