Compatibility studies with blends based on hydroxypropylcellulose and polyacrylonitrile

The solubility parameters of hydroxypropylcellulose (HPC) were measured with the viscosity method and estimated from proposing a group contribution approach for the prediction of δ based on the separation of the solubility parameter into three components (dispersion, polarity, and hydrogen bonding contributions). Hansen’s three dimensional solubility parameters were calculated approximately through the contributions of the structural groups. The compatibility of the HPC and polyacrylonitrile (PAN) blend system was studied with theoretical calculations as well as experimental measurements. Viscometric methods, polarized optical microscopy (POM), scanning electron microscopy (SEM), infrared spectrophotometric and thermogravimetry analysis (TGA) were employed for this investigation. The viscometric methods and polarized optical microscopy results were obtained from the blended solution in the range of 0–1.0 weight fraction of PAN, and the scanning electron microscopy, infrared spectrophotometric and thermogravimetry analysis results were obtained from the transparent films cast from the blended solutions that contained 0.2, 0.5 and 0.8 weight fractions of PAN, respectively. The results showed an excellent compatibility existed in the blends system, which may due to the strong hydrogen-bonding interaction between the hydroxyl group of HPC and the nitrile group of PAN.