Molecular dynamic in binary mixtures and polymer blends with large difference in glass transition temperatures of the two components: A critical review

The dynamics in highly asymmetric mixtures with large difference Tg of the two components are complex. At low values lower-Tg2 component only ?1-relaxation and its Tg?1 were found together a fast relaxation. Three different interpretations relaxation given. first one interpreted as JG ?-relaxation, ?2-relaxation is present but not resolved. second it localized noncooperative ??-relaxation low-Tg2 totally confined by frozen high-Tg1 component. third also ?2-relaxation, liquid-like cooperative. We review exhaustively experimental data many polymer blends to show unequivocally that observed ?-relaxation. Notwithstanding, confined-but-cooperative exists, albeit Experimental exclusively considered objectively utilized arrive at conclusions.