| Phase formation, morphology and their evolution of binary blends of polypropylene with poly(cis-butadiene) rubber were investigated by a Back Small Angle Laser Scattering (BSALS) on-line system and online sampling. The morphology formation process can be divided into three stages: early stage, intermediate stage and late stage. Phase Contrast Microscopy (PCM) and Small Angle Laser Scattering (SALS) measurements have been introduced to compare with the results of BSALS and the corresponding phase morphology were also observed using Scanning Electron Microscopy (SEM). The structure parameters, the correlation distance ac , average chord length L , radius of gyration Rg , and the invariant Q were obtained by applying the Debye-bueche statistical theory of scattering. The structure parameters and the integral of scattering intensity Ji,I m,hm?1 were calculated to describe the relationship between phase evolution and processing conditions.. The results shows that the changes mainly occurs in the initial stage of the mixing. In the late stage, the change levels off due to the dynamic equilibrium between the breakup and coalescence of particles. There exists a optimal rotating speed and blending temperature at which the phase structure is more exquisite. Moreover, sizes of particles increase as the volume fraction of the dispersed phase rises.The dynamical evolution of SEM patterns was discussed by diameter theory and character length theory respectively. The distribution of dispersed phase diameters was proven to be log-normal distribution by figure-estimation theory. Furthermore, two parametersσandμof log-normal distribution were calculated by linear regression, which are two effective parameters to characterize the dynamics of phase dispersion.Phase dispersion theory was proposed to study the dynamic process of polymer blending with the help of mineral processing theory. Two constants, dispersion coefficient n and process coefficient b, were calculated for the early dispersion stage to describe the varying velocity of the dispersed phase dimension.It's found experimentally that the scattering intensity I(q,t) should follow an exponential growth with time at the early dispersion stage from 1 s to 65 s, while at t>65 s, the slope levels off with time. And two theories, Semilogatithmic Plot Method and 1/3 Power Plot Method of early stage of phase dispersion in which two critical parameters, W(q) and Dd (or R(q), Ds) were calculated was proposed to describe the early stage of phase dispersion, the former parameter is defined as the decreasing rate of dispersed phase dimension, and the latter evaluated from the slope of W(q) or R(q) vs q2 plot is the distribution coefficient. The results gained by these two theories were consistent.Dynamic scaling and fractal behavior of phase dispersion in a binary polymer mixture of PP/PcBR during the blending process was studied. In the late stage of phase dispersion, a special fractal behavior was found, different overlapped line groups existing simultaneously and the temporal distribution being stochastic. We defined the special behavior as quasi-selfsimilarity and calculated different fractal dimensions by using the method of power spectrum and correlation function. The results show that the evolution of different fractal dimensions with time or composition is consistent with the average diameter of the dispersed phase. And we proposed a model of structure function, and the relationship between the structure function and the processing conditions was built up. The structure function fits the scaled data remarkably well and the power law indexβof the proposed structure function and the fractal dimension Dp are related according toβ=5-2Dp. And the theoretically calculated fractal dimension Dp,r is consistent with Dp,f gained by fitting the tail of the structure function.
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