Abstract:
The instrument for measuring the viscosity of dilute polyvinyl chloride solution was composed of 2 ccmponents, namely; viscometer bath and temperature controller. The viscometer bath contains an oB type Ubbelohde viscometer with holder, an ASTM 118C type thermometer, an agitator, a heating ceil, a sample solution tray and heat transfer
solution. The temperature controller consisted of a ther~ocouple and a controller.
After design and construction of the instrument for measuring the viscosity of dilute polyvinyl chloride solution was completed, the performance test was carried out by determining K-value for the solution with the relative viscosity of 1.00 g/100 ml cyclohexanone. The measured K-value agreed well with the commercial specification given
by the Thai Plastic Chemical Co., Ltd., the error was with in the range of 1.00 %. From the measurement of relative viscosity at various concentrations, the values of inherent viscosity, reduced viscosity and intrinsic viscosity were derived. The intrinsic viscosity was then correlated to the averaged molecular weight by Mark-Houwink equation.
Comparing the instrument under this research with the commercial unit, and also with the Gel Permeation Chromatography, it was found that the instrument unit under this research was more convenient, more economical and required lower maintenance cost.