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The vapor pressures of triacetin, triethylene glycol dinitrate, and metriol trinitrate for temperatures ranging from 11 to 75°C. and the constants of the integrated Clausius-Clapeyron equation are reported. Densities and refractive indices were also determined. The results obtained with metriol trinitrate are compared with those obtained by Piccardo.

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SynopsisThe effect of finite elongation on superposed infinitesimal torsional oscillations has been determined on two propellants, a carbon black-filled rubber and Solithane 113 (Galcit I), as a function of temperature at various fixed frequencies. Torsional storage modulus-temperature data for carbon black-filled rubber and propellant show that the effect of the imposed tensile elongation cannot be explained by any simple temperatureelongation shift relationship. The shift factors for the torsional moduli of these two polymeric systems have been calculated as a function of temperature at various tensile elongations. The WLF constants C l and C2 have been computed for these systems as a function of the elongation. The values of the constants a t 0% elongation are larger than those commonly found in unfilled materials. The temperature dependence of the shift factor of the torsional storage modulus was found to differ from that of the loss modulus in the cases of carbon blackfilled rubber and propellant. This difference is slight for the rubber and large for the propellant. The effect of increased elongation is to increase the difference in the shift behavior of the moduli for each of these filled polymers. The shape of the loss tangent curve of the propellants examined indicates that these propellants are not thermorheologically simple.The constants decrease with increasing elongation.

Vinyl stearate has been polymerized by 1000 kv. electrons with field intensities ranging from 1.0 × 103 to 20 × 103 rep per second; the polymers are considered to be branched. A discontinuity of reaction rate and molecular weight with respect to temperature was noted in the vicinity of monomer melting point, and it is suggested that in this temperature region, the diffusion constant for propagation is easily affected. A linear relationship between field intensity and polymerization rate, and a constancy in molecular weight with varying field intensities, at constant total dose, indicated that polymerization occurs in “volume elements.”