Fluid fracture processes were considered from time, temperature and concentration dependence of the ultimate property during the course of an investigation of fracture processes of polymeric liquids, rubberlike and hard plastic polymers. The samples were liquid polybutadiene (PBD)-benzen solutions with six different volume fractions of PBD (v
2) ranging from 0.374 to 0.782. The method and an apparatus used for the experiment are described in a previous report.
1) The drop weight W and the breaking time t
b were measured with various drop sizes at four different temperatures from 25°C to 40°C for each sample. The results may be summarized as follows:
(1) Time and temperature dependence; (i) Weight vs. time curves a
t different temperature for each sample can be superposed into an almost unified master curve by the horizontal shift along the time axis. (ii) The shift distance loga
T seem to follow the prediction of the Arrhenius equation. (iii) The apparent activation energy for the viscoelastic process from a plot of loga
T against l/T systematically increases with decreasing v
2.
(2) Time and concentration dependence; (i) Time-concentration superposition is possible on a plot of W vs. logt
b at each temperature, but it is impossible on a plot of W(ρ
s/ρ) vs. log t
b, where ρ is weight of PBD per unit volume of the solution, ρ
s is a ρ selected arbitrarily as reference. (ii) The shift distance loga
c was examined from the following two equations; -1/loga
c=f(v
s)+[f(v
s)]
2/γ(v
1-v
s)…(1), loga
c=log(η/η
s)={b(v
2-v
s)+c(v
22-vs
2)}/RT…(2), where v
1=1-v
2, v
s is a reference volume concentration, b, c are constants. The Eq. (1) has been presented by Fujita and Kishimoto
3), and corresponds to WLF equation. The E
q. (2) was lead from Andrade's viscosity equation η=A exp (U/RT), where U is replaced by interaction energy between polymer chain elements and solvent molecules in the from U=a+bv
2+cv
22 which was obtained form thermo-dynamical consideration of polymer solution. The present temperature-concentration region may be divided into three parts where loga
c obtained from experiment follow approximately the Eq>. (1) only, the Eq. (2) only, and both the Eqs.
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