In this part of the paper, the distribution of the tensile data on vulcanized SBR reinforced with Hi-Sil 233, especially the effect of cure on the general type of distribution, is investigated. Except lower content of vulcanization accelerator, the material tested has the same ingredients as the previous one. The experiment with the above material reveals that:
i) The trend of the distribution is similar to the previous results,
ii) The observed distribution of elongation data seems to be more close to doubly exponential one than that of tensile strength data, and
iii) According to cure progress, the observed distribution on tensile data is variable.

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Non-Newtonian flow of concentrated dioxane solutions of five polyvinyl chlorides(PVC) of different molecular weights has been studied. The dependences of the apparent and zero-shear viscosities on the rate of shear, molecular weight, and concentration are very similar to that in PVC-cyclohexanone solution.
The log-log plots of zero-shear viscosity against concentration for PVC-dioxane solutions are represented by two straight lines intersecting at one point (critical concentration, C_c). The slopes of lines are 5. 4 above C_c and 2.9 below C_c, respectively.
Furthermore, the products of critical concentration in volume fraction of polymer, V_ZC, multiplied by the chain length Z are found in the rannge from 130 to 210. The value C_cρ√Z densit of solution) is approximately constant and independent of the chain length as same as in the previous study on PVC-cyclohexanone solution. These results do not follow the Bueche′s theory.
C_cρ√Z value in dioxane is explained reasonably by using an Equivalent Gel Sphere Model, if the PVCchain association in dioxane solution is considered.

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A Pickup tackmeter was partially modified to prolong the autohesion measurements on raw rubber samples up to the order of 10³min. The dependence of the maximum tack strength, F, on the time of contact, t_p, in the longer time region could always be approximated by the following empirical equation,
F=F₀+(F_∞-F₀)(1-e^-tp/τp).
Here F₀ and F_∞ are the numerical parameters independent of t_p. The constant, τ_p, which is a measure of the rate process of the autohesion, was found to be roughly proportional to the 3.4th power of the average molecular weight of the sample for SBR. This finding on τ_p would suggest that the mobility of rubber molecules is an important factor to the autohesion process.

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TMTD, diphenylmethane and zic oxide were heated at 120 or 140°C under the atmosphere of nitrogen. Gaseous products and the products of low boiling points were captured and analyzed by a mass spectrometer. Carbon disulfide and thiocarbonyl were identified, and ratio of both gases was measured in the gaseous mixture. Dimethylamine, monomethylamine and carbon disulfide were identified, and ratio of these three compounds in the mixture of low boiling points was measured. Chemical analysis on carbon dioxide, thiocarbonyl, carbon disulfide and other products remained in the reaction system was also carried out. Exchange reaction between a sulfur atom in dithiocarbamategroup and oxygen atom in zinc oxide and further exchange reaction such as
_??_
must take place and result in the evolution of thiocarbonyl and carbon dioxide beside carbon disulfide accompanied by the evolution of amines.

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