PVC-plasticizer interaction model

Glass transition temperature is a very useful parameter which helps in the verifieation of plasticizing quality of various additives. It is assumed that energetic effects are created by binary heterocontacts which cause conformation redistribution in the neighborhood of these contacts. This assumption results in the following equation  

Tg glass transition temperature of mixture of polymer and plasticizer Tgi glass transition temperatures of components 

parameter of power equation, which depends on the difference between the interaction energies of the binary hetero- and homo-contacts 

Kj parameter of power equation, which depends on additional energetic contributions due to conformational entropy changes during binary contact formation VI2 weight fraction of the component with higher Tg2, corrected for the different volume expansivity of the blend components  

AOj the increments of expansion coefficients of plasticizer and polymer at glass transition temperature. 

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