Heats of dilution of water-soluble-polymer solutions (II) - heat interaction parameters of aqueous hydroxypropylcellulose and gelatin solutions determined by means of flow microcalorimeter

• Published in: Thermochimica acta 1990-06, Vol.163, p.155-160
• Main Authors: Maeda, Masaki, Yamamoto, Yoshitaka, Baba, Yoshihiro, Kagemoto, Akihiro
• Format: Article
• Language: English
• ISSN: 0040-6031; 1872-762X
• DOI: 10.1016/0040-6031(90)80392-C

In order to obtain information about the intermolecular interaction between the water-soluble-polymers, we measured the heats of dilution of hydroxypropylcellulose(HPC)-water and gelatin-water systems at 298K by the flow microcalorimeter. The heat of dilution for gelatin-water system proved to be exothermic and the heat interaction parameter x 1, determined by Van Laar equation was estimated to be about −1.00. However, the heat of dilution of HPC-water system moves from the exothermic to the endothermic with an increase of HPC concentration and x 1-value in dilute solution was estimated to be about −0.91. We found that the interaction between gelatin and water depends linearly on the gelatin concentration, but for HPC-water system, the interaction depends considerably on the HPC concentration. From the results of these interactions, the hydrophilic effect of these water-soluble-polymers for water was the order of gelatin > HPC. We will discuss the hydrophilic and hydrophobic interactions from the results of heats of dilution.