The pressure-volume-temperature (PVT) properties of a number of polymer liquid samples as a function of molecular weight have been investigated. The polymers studied included polyethylene (PE), poly(dimethyl siloxane) (PDMS), poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG). The properties of the end-groups and their effect on the density, compressibility, thermal pressure coefficient and expansivity as a function of their concentration are discussed. The specific volume exhibits a clear 1/M, dependence for those molecules with weakly interacting end-groups, i.e. PE and PDMS. The specific volume is found to be independent of M, for PEG and PPG, which can hydrogen-bond to each other. The data sets have been compared using equation-of-state theories
Посилання на статтю:
The pressure-volume-temperature properties of polyethylene, poly(dimethyl siloxane), poly (ethylene glycol ) and poly(propylene glycol) as a function of molecular weight / G. T. Dee, T. Ougizawa and D. J. Walsh // Polymer. – 1992. – Vol 33. – P. 3462-3469.