Poly superstructural morphology

Regime transition is presented when the data are analyzed with the Lauritzen and Hoffman kinetic theory. Di Lorenzo demonstrated that the discontinuity in the spherulite growth rate is not associated to any change in superstructural morphology. Tsuji et al. and Yuryev et al. also observed this unusual bimodal crystallization behaviour for pure PLLA, while the normal characteristic bell-shaped spherulite growth rate dependence was seen for poly(L/D-lactide) copolymers. 

Janus micelles are non-centrosymmetric, surface-compartmentalized nanoparticles, in which a cross-linked core is surrounded by two different corona hemispheres. Their intrinsic amphiphilicity leads to the collapse of one hemisphere in a selective solvent, followed by self-assembly into higher ordered superstructures. Recently, the synthesis of such structures was achieved by crosslinking of the center block of ABC triblock copolymers in the bulk state, using a morphology where the B block forms spheres between lamellae of the A and C blocks [95, 96]. In solution, Janus micelles with polystyrene (PS) and poly(methyl methacrylate) (PMMA) half-coronas around a crosslinked polybutadiene (PB) core aggregate to larger entities with a sharp size distribution, which can be considered as supermicelles (Fig. 20). They coexist with single Janus micelles (unimers) both in THF solution and on silicon and water surfaces [95, 97]. 

For both designs a microphase separated morphology was found with 20-50 nm peptide domains dispersed in a continuous poly(ethylene glycol) phase. Furthermore, a 100-150 nm superstructure was observed in cast films, which was explained to result from the polydispersity and multiblock character of the polymers. The mechanical properties of fibers and films made from these block copolymers could be modulated by manipulating the length and nature of the constituent blocks. Similar work was reported by Shao et al. [47]. 

Various linear synthetic analogs of the natural active polyamines in biosilica formation on the basis of linear poly(ethylene imine) or polyfpropylene imine) were recently synthesized and reported to accelerate the silk acid condensation even more than the above-mentioned silaffins [226]. This imphes that it is not the silaffin protein superstructure that is responsible for its catalytic activity,as is the case for example in enzymes. In addition, poly(L-lysine) also led to modified silica morphologies such as fibers or ladders [227]. 

Polyethylene, isotactic polypropylene, isotactic polystyrene, poly(etherether ketone) Permanganic acid Lamellar morphology and superstructure are revealed. Artefacts have been reported in low-magnification images... 

Similar crystallization behavior, where the ordered melt structure was destroyed upon crystallization and replaced by alternating lamellae with a spherulitic superstructure was also observed in diblock copolymers of poly(ethylene oxide-fe-(l,2-butylene oxide)) [109], poly(ethylene oxide-6-ethylethylene) [110],poly(ethylene oxide-6-isoprene) [111], poly(ethylene-6-(head-to-head propylene)) [112],poly(ethylene-6-ethylethylene) [113] and poly(ethylene-6-(ethylene-a/f-propylene)) [113], and a triblock copolymer of poly(ethylene oxide-6-styrene-6-ethylene oxide) [114]. In all instances, the solid-state morphology was characterized by a semicrystalline lamellar structure regardless of the initial melt morphology. 

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