| The formation and evolution on phase behavior and morphology of PS/PEimmiscible blends during melton and mixing was discussed in this paper. The phasecontrast microscopy (PCM) patterns in real space were transformed into patterns inwave-number space by 2-dimensional Fourier transformation (2DFT). The evolutionlaw of patterns during melt mixing or with composition fraction changing werediscussed by Fourier analysis parameters, such as hm ,φH , Angle spectrum and so ?1 /Von, when the conditions (temperature, shear rate) were changed. A scale functioncalculated by Fourier pattern was defined to investigate the dynamical self-similarityof patterns during melton and mixing. And two fractal dimensions, Dp and Dsp , whichcharacterize the phase dispersion degree, were deduced. The dynamical evolution ofSEM patterns was discussed by diameter theory and character length theoryrespectively. The distribution of dispersed phase diameters was proven to belog-normal distribution by figure-estimation theory. Furthermore, two parametersσ andμ of log-normal distribution were calculated by linear regression, which aretwo effective parameters to characterize the dynamics of phase dispersion. A scalefunction calculated by character length distribution was defined to investigate thedynamical self-similarity of the probability density distribution of character length.Then, the fractal dimension, DΛ , which can characterize the phase dispersion degree,was deduced. The melt mixing process of this blends with different fractions werediscussed by dynamical small angle laser light scattering (SALS). Some characterparameters of SALS (Integral invariant, Q ; Average chord length, L1; Correlationdistance, ac 2 ; Average gyration radius, Rg1; et al.) were used to discuss themechanism of the phase dispersed dynamics. Two fractal dimensions, Df and Ds ,calculated by SALS were deduced, which can characterize the spatial distribution andphase dispersion degree respectively. The phase spatial fluctuation law was discussedby PCM patterns. And three fractal dimensions, D3 , Dmp and Dmf which can ccharacterize the phase spatial fluctuation during melt mixing were deduced. The results demonstrate that the melt mixing process of PS/PE blends can bedivided into 3 regions according to their dynamical mechanisms. The dispersed phaseevolves with different dynamical self-similarity in the first region and the end regionrespectively. In the first region, the dispersed phase breaks up into smaller pellets. Andthe break-up coefficient, α , are about -0.26 of PS/PE (vol.10/90) and about -0.65 ofPS/PE (vol. 50/50) respectively. We find that the break-up mechanism in this region isapproximately to the break-up mechanism of mineral under the mechanical shear. Theaverage dispersed diameter in the end region almost doesn't change with the increaseof the mixing time, demonstrating the balance between the break-up and coalescenceof dispersed phase. The second region is the transition region of the first and the endregion. The distribution of phase size is log-normal distribution, which can becharacterized by the parameters σ and μ . The character length theory can calculatethe phase size near the phase inversion and can investigate the self-similarity ofpatterns during melt mixing. The results also show that the phase region size, theself-similarity and the evolution law of phase dispersion dynamics can be investigatedin wave-number space by 2DFT of patterns in real space. So, the Fouriertransformation is an excellent means to study the phase dispersion dynamics. Theresults about the phase dispersion dynamics mechanism obtained by dynamical SALSare similar to that by other means. And the dynamical melt mixing process can bestudied on-line by dynamical SALS. So the dynamical SALS is also an ef...
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