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Langmuir monolayer using a Langmuir film balance and atomic force microscopy (AFM) a blend of PS homopolymer and a block copolymer of styrene - methyl methacrylate ( PS - b - PMMA ) and LB film were carried out characterization . Studied the composition of the blends and copolymers composed of PS / PS-b-PMMA blends at the air / water interface aggregation behavior . The results show that the PS / PS -b - PMMA blend of pi - A isotherm , similar to the phase of the PS-b - PMMA block copolymer , there is no obvious platform , the compression initial pressure increases slowly , the latter part of the pressure began to rapidly rise. With the PS blends homopolymer content increases , the pi -A curve is offset to the left , the maximum mean molecular area gradually decreases ; hysteresis curve of the hysteresis area increases gradually , the hysteresis phenomenon is more pronounced . With the content of PMMA in the copolymer increases , the pi - A isotherm is offset to the right , the maximum mean molecular area gradually increases ; hysteresis curve , hysteresis area gradually decreases , the hysteresis phenomenon is gradually weakened . Seeks atoms from the LB film can be seen , when the PS homopolymer content of 20 % , mainly rendered circular micelles , the greater the content of PMMA block copolymer , the smaller the size of the micelle formed ; PMMA content . low blend formed a rod-like micelles and circular hybrid structure of the micelles ; , rod-like micelles began to appear, the micelle size increases gradually with increasing migration pressure . When the PS homopolymer content increased to 40% , mainly as a rod-like micelles . When the PS homopolymer content reaches 60% , with the PMMA block copolymer content increases successively forming a close-packed structure , necklaces network structure and closely-spaced circular micelle . When the PS homopolymer content is further increased to 80% , can preferably formed the necklace network structure ; as migration pressure increases , the intensity of the structure increases .
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