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An amphiphilic graft copolymer PAA-g-C8PhEO10Ac with poly(acrylic acid) as a main chain and octylphenyl polyoxylethylene ether(C8PhEO10) as graft chains was synthesized via free radical copolymerization of acrylic acid (AA) and amphiphilic C8PhEO10Ac maromonomers. The number average molecular weight of the copolymer was determined to be 4.37×104 by gel permeation chromatography(GPC). The structure and composition of the copolymer obtained were characterized by FTIR and 1H-NMR. The molar ratio of acrylic acid monomer to macromonomer is 9∶1 in the copolymer and 32 C8PhEO10 branch chains attach to a poly(acrylic acid) backbone. Self-assembly behavior of PAA-g-C8PhEO10Ac in aqueous solution was preliminary studied by means of surface tension measurements, fluorescent probe and TEM. It was found that spherical micelles are formed in water phase at cmc1 and cmc2. As compared with those at cmc1, the surface tension of the copolymer solution and the polarity in the micellar core further decrease at cmc2. Furthermore the diameter of the micelles increases and the micelles become compact. The presence of 1.0%(w) sodium chloride results in the lower surface tension of the copolymer solution and the weaker polarity in micellar core.

The defects in oxygen plasma irradiated Si have been studied. It is found that two kinds of defects E1(Ec-0.46 eV) and E2 (Ec-0.04 eV) are generated in the sample. The deep level optical spectroscopy reveals that defects E2 has a strong electron-phonon coupling, its Frank-Condon shift is 0.76 eV. For E1, the coupling is weaker, its Frank-Condon shift is 0.04 eV. The analysis shows that the phonon modes coupling to defects E1 and E2 is 28.7 meV and 20 meV respectively.