G. J. Howard

Influence of filler particles on the mobility of polymer molecules. II. Effect of filler type

Abstract Changes in glass transition temperature and heat capacity at the glass transition have been shown to be dependent on the concentration of filler. The polymer studied was poly (vinyl chloride-co-vinyl acetate) with 10% vinyl acetate, and the fillers were Aerosil 300, Aerosil OX50, carbon (Graphon C), aluminum oxide C, and titanium dioxide P25. The fillers were all of very small particle size, ∼ 10–50 nm. The degree of dispersion of each filler was kept constant by using a master batch and diluting with polymer solution. The Tg results show a strong influence of filler at low concentration which rises to a plateau. The change in heat capacity of the polymer at Tg diminishes with increase in filler concentration, although to a less marked extent, than the change in Tg