OPO-POSS/PC composites generally exhibited transparency similar to that of PC. A slight decrease in transparency was observed as the DOPO-POSS concentration was increased from 2 to 6 wt.%. Due to that the DOPO-POSS particles were of micron size before blending together with the PC pellets, certain transparency of these composites could correlate with the nano-scale dispersion of the DOPO-POSS. See Morphology analysis section.