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Abstract
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Single crystals of double crystalline block copolymers of poly (ethylene glycol) (PEG)-b-poly(ε-
caprolactone) (PCL) and PEG-b-poly(L-lactide) (PLLA) were grown from dilute solution in homo- and mixed-brush
systems. Crystallization behavior of biodegradable one end-restricted crystallizable PCL and PLLA chains in homoand mixed-brush nanostructures were investigated. The chemical and physical circumstances of crystallizable
brushes were altered. The physical environment was adjusted by amorphism/crystallinity and rigidity/ flexibility of
neighboring brushes. The chemical environment was manipulated by interaction and miscibility of various brushes.
Distinct single crystals were grown with mixed-brushes of amorphous-crystalline (polystyrene (PS), poly (methyl
methacrylate) (PMMA), PCL, PLLA, double crystalline (PCL/PLLA), and rod-crystalline polyaniline (PANI)/PCL
or PLLA. Surrounding was only effective on hindrance or nucleation commencement of crystallization for
crystallizable brushes and had no effect on crystallization features. Novel three-layer fully single-crystalline
nanostructures, whose characteristics were fixed via changing the crystallization temperature, were also developed.
For long crystallizable tethers, crystallization increased both brush and substrate thicknesses.
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