Dislocation-controlled perforated layer phase in a PEO- b-PS diblock copolymer.
نویسندگان
چکیده
Small angle x-ray analyses show that the shear-induced hexagonal perforated layer phase in a poly(ethylene oxide)- b-polystyrene diblock copolymer consists of trigonal (R3;m) twins and a hexagonal (P6(3)/mmc) structure, with trigonal twins being majority components. Transmission electron microscopy reveals that the hexagonal structure is generated through sequential intrinsic stacking faults on the second layer from a previous edge dislocation line, while the trigonal twins are formed by successive intrinsic stacking faults on neighboring layers due to the plastic deformation under mechanical shear.
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ورودعنوان ژورنال:
- Physical review letters
دوره 86 26 Pt 1 شماره
صفحات -
تاریخ انتشار 2001