Abstract
Viscoelasticity of coating film and thin film has hitherto been measured by many but the data thereby obtained are not free from the effect of the load that hung at the lower end of the sample. In order to remove the influence of the load, a torsional pendulum is devised for low frequency measurements, with which satisfactory results are obtained. A piano wire suspends a cross made of a horizontal iron rod and a vertical steel rod to which the upper end of the sample strip is clamped, the lower end of the sample being fixed.
Variation of complex rigidity modulus of polystyrene thin film with temperature in the range from 20°C to 120°C is observed at about 0.2 cps. Two maximum peaks of tan δ are found, the main peak at about 116°C and the small secondary one at about 56°C.
