Macro-phase separation

Figure 7(c) shows the phase stmcture of the blend polymer composed of EBR/PLA (15/85 wt%). Macro-phase separated EBR domains in the PLA matrix were observed. By adding 5 wt% of PE-/ -PMMA (PMMA contents 75 wt%) to EBR/PLA (10/85 wt%) as a compatibilizer, finely dispersed EBR domains are observed in Figure 7(d). As a result, this polymer indicates very high Izod impact strength value (378 J/m) vis-a-vis the blend polymer s value... 

P(S-b-MMA) copolymer the formation of miceUes, and the micro and macro phase separation. Same morphology was observed in solution and after solvent evaporation 1990, 1991, 1994... 

The size of water droplets dispersed in the starting organic monomer liquid and the stability of the emulsion depend on the water-to-AOT molar ratio IV. The smallest droplets and the most stable emulsion are formed when IV=1. This ratio may change from 1 to 18, but, beyond this value, the initial system becomes unstable and macro phase separation takes place. In principle, IV determines the surface area, pore volume, and pore size... 

An important factor to consider on the blending of polymeric materials is that most polymers are incompatible with polypropylene on the molecular scale. This might cause many problems, such as macro-phase separation during blending, low interface adhesion, low tensile transfer rate, and low physical properties, which may be even lower than the unmodified polymer. To sustain good fiber properties, controlling the phase structure and interface adhesion is a necessity. 

Nh and Nab are the polymerization degrees of homopolymer and block copolymer, respectively. In fact, with increasing Nj, the macro phase separation is enhanced in homopolymer and block copolymer binary blends. Thomas et al. found in their small X-ray scattering [26] and TEM [27] investigations that a sphere-to-rod transition of micellar shape takes place at lower concentration with increasing unit number of solvent molecules. However, only a limited number of studies have been reported on the self-assemblies of A-B type diblock copolymer in polar solvents [28]. 

H. Frielinghaus, N. Hermsdorf, K. Ahndal, K. Mortensen, L. Messe, L.J. Corvazier, P.A. Fairclough, A.J. Ryan, P.D. Olmsted, I.W. Hamley, Micro- vs. macro-phase separation in binary blends of poly(styrene)-poly(isoprene) and poly(isoprene)-poly(ethylene oxide) diblock copolymers. Europhysics Letters 53 (2001) 680-686, http //dx.doi.org/10.1209/ ephi2001-00205-7. 

Polymerization with up to the high conversion state is considered as a ehemieal process in a system changing its own phase state. Thus, the main accent is on the concentration at which the macro-phase separation of a polymerizing system forms new reactive zones the contribution of every one of them to the total kinetics depends on the kinetic characteristics of the process in that particular zone and its volumetric part. 

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