The effect of temperature and polymer concentration on dynamic surface tension and wetting ability of hydroxypropylmethylcellulose solutions

The purpose of the present study was to evaluate quantitatively the changes of dynamic surface tension and contact angle of hydroxypropylmethylcellulo se (HPMC) aqueous solutions as a function of temperature and polymer concen tration of the examined solutions. HPMC aqueous solutions of different conc entrations (1%, 2%, 3%, 4% w/w) were prepared without plasticizer and with 1% w/w Lutrol F127. Dynamic surface tension of the prepared solutions was d etermined by the Du Nouy ring method of the KSV Sigma 70 computer-controlle d and programmable tensiometer. The dynamic contact angle of Avicel PH-101 tablets was measured against HPMC solutions of various concentrations by th e plate method of the KSV Sigma 70 tensiometer. The obtained results indica te that dynamic surface tension measurement can be applied for the accurate determination of the thermal gelation temperature of the prepared HPMC sol utions. With increasing concentration of HPMC, dynamic contact angle values of solutions also increased thus decreasing the spreading behavior on the surface of Avicel tablets.