Trisilanolphenyl POSS (TSP-POSS ) with open cage structure was incorporated into PU backbones in concentrations of 0 wt%

3.06 wt%

6.56 wt%

10.13 wt%

12.11 wt%

15.36 wt% and 19.87 wt%

respectively by molecular mechanics and molecular dynamics methods to elucidate the effect of TSP-POSS on structure and thermal properties of polyurethane hybrid composites.These hybrid composites models were characterized by mean square displacement

radial distribution function

temperature-volume behavior and X-ray diffraction at molecular level.The result shows: as TSP-POSS loading is lower than 12.11 wt%

the mobility of the polymer chains is enhanced apparently due to the humping open cage structure of TSP-POSS which increases the average distance between the polymer chains; as TSP- POSS loading is higher than 12.11 wt%

TSP-POSS self-reunites and crystalline clusters are formed which lead to restricting the motion of the polymer chains.According to temperature-volume behavior analysis

the introduction of TSP-POSS can significantly increase the glass transition temperature of polyurethane hybrid composites and thus

the introduction of TSP-POSS is supposed to improve the hybrid composite's thermal stability with reasonable concentration in application.