MECHANICAL I'HOPKRTIIOS OF POLYMKRS 



135 



Fig. 8 — Dual reflecting block assembly for measuring high frequency shear 

 impedances of liquids. 



vents with concentrations ranging from zero per cent to 10 per cent. 

 Polyisobiitylene is a polymer molecule having the chemical formula 



"CH3 H 



C- 



C- 



CH3 H 



Non-planar zigzag segments can be expected in the liquid state. Fig. 10 

 shows measured curves for 20 kc of the resistance and reactance for 

 solutions of viscosity average molecular weight of 3,930,000 in cyclo- 

 hexane. Four values of concentration were used and two temperatures 

 were measured. For pure cyclohexane, the resistance and reactance 



