Raspberry morphology

Fig. 15 Schematic of the morphological arrangement in PPE/SAN blends compatibilized by SBM triblock terpolymers - nanostructured raspberry morphology (reprinted from [45])...

SBM) as a compatibilizer. As a result of the particular thermodynamic interaction between the relevant blocks and the blend components, a discontinuous and nanoscale distribution of the elastomer at the interface, the so-called raspberry morphology, is observed (Fig. 15). Similar morphologies have also been observed when using triblock terpolymers with hydrogenated middle blocks (polystyrene-W<9ck-poly(ethylene-C0-butylene)-Wock-poly(methyl methacrylate), SEBM). It is this discontinuous interfacial coverage by the elastomer as compared to a continuous layer which allows one to minimize the loss in modulus and to ensure toughening of the PPE/SAN blend [69],... 

Fig. 17.6 Transmission electron micrograph of polypyrrole-silica nanocomposite particles synthesized in aqueous media using a commercial 20 nm silica sol. Note the unusual raspberry morphology. (Reproduced with permission from Ref. 64.)...

The above computations for the fiee energy changes for composite latex particles have shown that only core-shell, inverted core-shell and hemispherical particles are stable in a thermodynamic sense. All of the other reported morphologies (e.g. sandwich-like , raspberry or confetti-like particles or occluded domains) are non-equilibrium, kinetically controlled structures, prepared... 

Li et al. [51] prepared monodisperse microspheres by distillation precipitation polymerization of DVB and NIPAM with 2,2-azobisisobutyronitrile (AIBN) as initiator in acetonitrile, in the absence of any surfactant. Next, latex particles of poly(EGDMA-co-AA) were assembled onto the microspheres to afford a corecorona composite polymer particle with a raspberry-like morphology, strengthened by hydrogen-bonding interaction. 

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