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Single crystals having matrix-dispersed surface morphologies were prepared and characterized.

Synthesis of amine-terminated polyethylene glycol benzoate (ATPEGB). The three macroinitiators, i.e., ATPEGB 5000 , ATPEGB 6000 and ATPEGB 35000 were synthesized by the following procedure: PEG and 4-amino benzoic acid (equivalent moles) and xylene (100 mL for PEG 5000 and 6000, 120 mL for PEG 35000) were taken into a two-necked reaction flask equipped with a stirrer and a Dean and stark trap. The catalytic amount of p-toluene sulfonic acid (PTSA) was added to the mixture. The generated water was then removed as an azeotrope until the reaction completed. It was in need of refluxing at 140 °C for 5 h. The solvent was then removed and the solid product was dissolved in chloroform. Then, unreacted 4-amino benzoic acid was filtered and the solvent of the obtained solution was evaporated. The final solid product was dried in vacuum for 48 h.Synthesis of block copolymers. Ammonium peroxydisulfate (APS) and potassium hydrogen biiodate (PHD) were dissolved in sufficient amount of 1 M sulfuric acid solution in a 400 mL beaker. A solution of aniline and ATPEGB in chloroform was then gently added at 6 °C (in this

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Self-assembled mixed-brushes with co-continuous surface morphologies were developed from melt of poly(ethylene glycol)-b-polystyrene (PEG-b-PS) and poly(ethylene glycol)-bpoly(methyl methacrylate) (PEG-b-PMMA) diblock copolymers by a self-seeding technique.Some features of solution-grown matrix-dispersed mixed-brushes having controllable characteristics were briefly recalled and compared with the behavior of corresponding meltgrown mixed-brushes. The preceding observations implied some major differences between two growth systems. An obvious deduction made from atomic force microscopy height images was that the patterned leopard-skin like surface morphology of solution induced mixed-brush single crystals changed to co-continuous morphologies in melt state. Beside the alteration of growth environment from solution to the melt, this phenomenon was assigned to the dominant kinetic effect replaced instead of the prevailed thermodynamic effect in dilute solution systems. The ratio of PMMA-to PS-covered surface area on the substrate, increased from 20/80 for the solution-grown mixed-brush single crystals to 50/50 for the melt-grown ones. Owing to 2 accelerated kinetic in melt-grown mixed-brush single crystals, for a same molecular weight, the thickness of a melt-grown mixed-brush single crystal was significantly greater than that observed for solution-grown mixed-brush single crystal. Similar trends, nevertheless, were observed for the thickness changes with molecular weight and crystallization temperature. The lateral sizes of melt-grown single crystals were about 4-fold larger than those for solution-grown single crystals (e.g., 24 vs. 6 µm). The thicknesses were also proved by the interface distribution function of small angle x-ray scattering analysis.