The soluble poly(vinyl alcohol)-g-poly(ethylene glycol) monomethyl ether(PVA-g-MPEG) graft copolymer was prepared by two-step synthesis. The structure of the PVA-g-MPEG was characterized by 1H NMR. The phase change an...The soluble poly(vinyl alcohol)-g-poly(ethylene glycol) monomethyl ether(PVA-g-MPEG) graft copolymer was prepared by two-step synthesis. The structure of the PVA-g-MPEG was characterized by 1H NMR. The phase change and crystallization behavior were analyzed by DSC and POM. The phase change behavior presented solid-to-solid state; the phase transition process was reversible. Compared with pure MPEG, the phase change temperature and enthalpy of graft copolymer declined because of the addition of PVA. Due to the intermolecular interaction and chemical bond, the crystalline shape of the graft copolymer was changed.展开更多
以大豆磷脂为原料,首先制备出大豆磷脂酸钠,再与聚乙二醇单甲醚2000对甲苯磺酸酯(mPEG_2000-OTs)反应制备大豆磷脂酰聚乙二醇单甲醚2000(SP-mPEG_2000)。实验结果为:以65mg Na H处理大豆磷脂得到大豆磷脂酸钠,m(大豆磷脂酸钠)∶m(mPEG_2...以大豆磷脂为原料,首先制备出大豆磷脂酸钠,再与聚乙二醇单甲醚2000对甲苯磺酸酯(mPEG_2000-OTs)反应制备大豆磷脂酰聚乙二醇单甲醚2000(SP-mPEG_2000)。实验结果为:以65mg Na H处理大豆磷脂得到大豆磷脂酸钠,m(大豆磷脂酸钠)∶m(mPEG_2000-OTs)=0.45∶1,反应时间为4h,反应温度为90℃,转化率为71.2%,产物为淡黄色固体。经~1HNMR和IR表征,证明为SP-mPEG_2000。该合成路线反应条件温和,大豆磷脂利用率高。SP-mPEG_2000水溶液临界胶束浓度为0.5g/L,此时表面张力为42mN/m。通过SP-mPEG_2000对正己烷和水形成的乳状液的稳定性表征,表明产物的动力学稳定性优于大豆粉末磷脂。展开更多
文摘The soluble poly(vinyl alcohol)-g-poly(ethylene glycol) monomethyl ether(PVA-g-MPEG) graft copolymer was prepared by two-step synthesis. The structure of the PVA-g-MPEG was characterized by 1H NMR. The phase change and crystallization behavior were analyzed by DSC and POM. The phase change behavior presented solid-to-solid state; the phase transition process was reversible. Compared with pure MPEG, the phase change temperature and enthalpy of graft copolymer declined because of the addition of PVA. Due to the intermolecular interaction and chemical bond, the crystalline shape of the graft copolymer was changed.
文摘以大豆磷脂为原料,首先制备出大豆磷脂酸钠,再与聚乙二醇单甲醚2000对甲苯磺酸酯(mPEG_2000-OTs)反应制备大豆磷脂酰聚乙二醇单甲醚2000(SP-mPEG_2000)。实验结果为:以65mg Na H处理大豆磷脂得到大豆磷脂酸钠,m(大豆磷脂酸钠)∶m(mPEG_2000-OTs)=0.45∶1,反应时间为4h,反应温度为90℃,转化率为71.2%,产物为淡黄色固体。经~1HNMR和IR表征,证明为SP-mPEG_2000。该合成路线反应条件温和,大豆磷脂利用率高。SP-mPEG_2000水溶液临界胶束浓度为0.5g/L,此时表面张力为42mN/m。通过SP-mPEG_2000对正己烷和水形成的乳状液的稳定性表征,表明产物的动力学稳定性优于大豆粉末磷脂。