聚醋酸乙烯酯的合成及其在超临界二氧化碳中的相行为（英文）
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摘要
利用可逆加成-断裂链转移自由基聚合法制备了3个具有可控分子量和窄分子量分布的聚醋酸乙烯酯单聚物,并讨论了反应温度和引发剂加入量对聚合过程的影响.然后,通过浊点法测定了相对制得的聚合物在加压的二氧化碳中的相行为.结果表明,聚合物的浊点随着分子量、聚合物浓度和温度的增加而增大,在0.12%的质量浓度和35℃温度下,分子量为1 550, 2 120和2 960 g/mol的聚醋酸乙烯酯的浊点压力分别为13.48, 13.83和15.43 MPa,该结果表明聚醋酸乙烯酯在较低压力的超临界二氧化碳中溶解度十分有限.
Three poly(vinyl acetate)(PVAc) oligomers with controlled molecular weight and narrow molecular distribution are synthesized by reversible addition-fragmentation chain transfer(RAFT) polymerization. The effects of the reaction temperature and the added amount of initiator of the PVAc polymerization are discussed. In addition, the phase behavior of the prepared PVAc in pressured CO_2 is determined via the cloud point method. The results indicate that the cloud point of PVAc increases with the increase in the molecular weight, the PVAc concentration, and the temperature. The cloud point pressures for the PVAc mass concentration of 0.12 % with the molecular weight of 1 550, 2 120, and 2 960 g/mol are 13.48, 13.83 and 15.43 MPa, respectively, at the temperature of 35 ℃. It reveals that the solubility of PVAc in ScCO_2 at relatively low pressure is remarkably limited.
Three poly(vinyl acetate)(PVAc) oligomers with controlled molecular weight and narrow molecular distribution are synthesized by reversible addition-fragmentation chain transfer(RAFT) polymerization. The effects of the reaction temperature and the added amount of initiator of the PVAc polymerization are discussed. In addition, the phase behavior of the prepared PVAc in pressured CO_2 is determined via the cloud point method. The results indicate that the cloud point of PVAc increases with the increase in the molecular weight, the PVAc concentration, and the temperature. The cloud point pressures for the PVAc mass concentration of 0.12 % with the molecular weight of 1 550, 2 120, and 2 960 g/mol are 13.48, 13.83 and 15.43 MPa, respectively, at the temperature of 35 ℃. It reveals that the solubility of PVAc in ScCO_2 at relatively low pressure is remarkably limited.
引文
[1] Girotra P,Singh S K,Nagpal K,et al.Supercritical fluid technology:A promising approach in pharmaceutical research[J].Pharmaceutical Development and Technology,2013,18:22-38.DOI:10.3109/10837450.2012.726998.
[2] Esfandiari N.Production of micro and nano particles of pharmaceutical by supercritical carbon dioxide[J].Journal of Supercritical Fluids,2015,100:129-141.DOI:10.1016/j.supflu.2014.12.028.
[3] Nuchuchua O,Nejadnik M R,Goulooze S C,et al.Characterization of drug delivery particles,produced by supercritical carbon dioxide technologies[J].Journal of Supercritical Fluids,2017,128:244-262.DOI:10.1016/j.supflu.2017.06.002.
[4] Girard E,Tassaing T,Marty J D,et al.Structure-property relationships in CO2-philic (co)polymers:Phase behavior,self-assembly,and stabilization of water/CO2 emulsions[J].Chemical Reviews,2016,116:125-4169.DOI:10.1021/acs.chemrev.5b00420.
[5] Kilic S,Michalik S,Wang Y,et al.Phase behavior of oxygen-containing polymers in CO2[J].Macromolecules,2007,40:1332-1341.DOI:10.1021/ma061422h.
[6] Oshea K E,Kirmse K M,Fox M A,et al.Polar and hydrogen-bonding interactions in supercritical fluid-effect on the tautomeric equilibrium of 4-(phenylazo)-1-naphthol[J].Journal of Physical Chemistry,1991,95:7863-7867.DOI:10.1021/j100173a057.
[7] Rindfleisch F,DiNoia T P,McHugh M A J.Solubility of polymers and copolymers in supercritical CO2[J].Journal of Physical Chemistry,1996,100:15581-15587.DOI:10.1021/jp9615823.
[8] Shen Z,McHugh M A,Xu J,et al.CO2-solubility of oligomers and polymers that contain the carbonyl group[J].Polymer,2013,44:1491-1498.DOI:10.1016/s0032-3861(03)00020-x.
[9] Zhang S C,Luo Y L,Yang H W,et al.Functional oligo(vinyl acetate) bearing bipyridine moieties by RAFT polymerization and extraction of metal ions in supercritical carbon dioxide[J].Polymer Chemistry,2013,4:3507-3513.DOI:10.1039/c3py00212h.
[10] Zhu T,Gong H,Dong M,et al.Phase behavior for poly(vinylacetate) + carbon dioxide + cosolvent ternary systems[J].Journal of Chemical & Engineering Data,2018,63(1):187-196.DOI:10.1021/acs.jced.7b00805.
[11] Zhu T,Gong H,Dong M,et al.Phase equilibrium of PVAc + CO2 binary systems and PVAc + CO2 + ethanol ternary systems[J].Fluid Phase Equilibria,2018,458:264-271.DOI:10.1016/j.fluid.2017.11.029.
[12] Jiao Z,Fan W,Wang X,et al.Synthesis of CO2-philic amphiphilic block copolymers by RAFT polymerization and its application on forming drug-loaded micelles using ScCO2 evaporation method[J].Journal of Drug Delivery Science and Technology,2018,44:13-18.DOI:10.1016/j.jddst.2017.11.024.
[13] Patel V K,Vishwakarma N K,Mishra A K,et al.(S)-2-(ethyl propionate)-(O-ethyl xanthate)- and (S)-2-(Ethyl isobutyrate)-(O-ethyl xanthate)-mediated RAFT polymerization of vinyl acetate[J].Journal of Applied Polymer Science,2012,125,2946-2955.DOI:10.1002/app.36233.
[14] Chen K P,Grant N,Liang L Y,et al.Synthesis of CO2-philic xanthate-oligo(vinyl acetate)-based hydrocarbon surfactants by RAFT polymerization and their applications on preparation of emulsion-templated materials[J].Macromolecules,2010,43:9355-9364.DOI:10.1021/ma101182f.
[15] Han S,Wang W,Jiao Z,et al.Solubility of vitamin E acetate in supercritical carbon dioxide:Measurement and correlation[J].Journal of Chemical & Engineering Data,2017,62(11):3854-3860.DOI:10.1021/acs.jced.7b00550.
[16] Lee H,Pack J W,Wang W X,et al.Synthesis and phase behavior of CO2-soluble hydrocarbon copolymer:poly(vinyl acetate-alt-dibutyl maleate) [J].Macromolecules,2010,43:2276-2282.DOI:10.1021/ma902505h.
[17] Wu Y,Zhang W,Zhang Z B.Initiator-chain transfer agent combo in the RAFT polymerization of styrene[J].Chemical Communications,2014,50:9722-9724.DOI:10.1039/c4cc03699a.
[2] Esfandiari N.Production of micro and nano particles of pharmaceutical by supercritical carbon dioxide[J].Journal of Supercritical Fluids,2015,100:129-141.DOI:10.1016/j.supflu.2014.12.028.
[3] Nuchuchua O,Nejadnik M R,Goulooze S C,et al.Characterization of drug delivery particles,produced by supercritical carbon dioxide technologies[J].Journal of Supercritical Fluids,2017,128:244-262.DOI:10.1016/j.supflu.2017.06.002.
[4] Girard E,Tassaing T,Marty J D,et al.Structure-property relationships in CO2-philic (co)polymers:Phase behavior,self-assembly,and stabilization of water/CO2 emulsions[J].Chemical Reviews,2016,116:125-4169.DOI:10.1021/acs.chemrev.5b00420.
[5] Kilic S,Michalik S,Wang Y,et al.Phase behavior of oxygen-containing polymers in CO2[J].Macromolecules,2007,40:1332-1341.DOI:10.1021/ma061422h.
[6] Oshea K E,Kirmse K M,Fox M A,et al.Polar and hydrogen-bonding interactions in supercritical fluid-effect on the tautomeric equilibrium of 4-(phenylazo)-1-naphthol[J].Journal of Physical Chemistry,1991,95:7863-7867.DOI:10.1021/j100173a057.
[7] Rindfleisch F,DiNoia T P,McHugh M A J.Solubility of polymers and copolymers in supercritical CO2[J].Journal of Physical Chemistry,1996,100:15581-15587.DOI:10.1021/jp9615823.
[8] Shen Z,McHugh M A,Xu J,et al.CO2-solubility of oligomers and polymers that contain the carbonyl group[J].Polymer,2013,44:1491-1498.DOI:10.1016/s0032-3861(03)00020-x.
[9] Zhang S C,Luo Y L,Yang H W,et al.Functional oligo(vinyl acetate) bearing bipyridine moieties by RAFT polymerization and extraction of metal ions in supercritical carbon dioxide[J].Polymer Chemistry,2013,4:3507-3513.DOI:10.1039/c3py00212h.
[10] Zhu T,Gong H,Dong M,et al.Phase behavior for poly(vinylacetate) + carbon dioxide + cosolvent ternary systems[J].Journal of Chemical & Engineering Data,2018,63(1):187-196.DOI:10.1021/acs.jced.7b00805.
[11] Zhu T,Gong H,Dong M,et al.Phase equilibrium of PVAc + CO2 binary systems and PVAc + CO2 + ethanol ternary systems[J].Fluid Phase Equilibria,2018,458:264-271.DOI:10.1016/j.fluid.2017.11.029.
[12] Jiao Z,Fan W,Wang X,et al.Synthesis of CO2-philic amphiphilic block copolymers by RAFT polymerization and its application on forming drug-loaded micelles using ScCO2 evaporation method[J].Journal of Drug Delivery Science and Technology,2018,44:13-18.DOI:10.1016/j.jddst.2017.11.024.
[13] Patel V K,Vishwakarma N K,Mishra A K,et al.(S)-2-(ethyl propionate)-(O-ethyl xanthate)- and (S)-2-(Ethyl isobutyrate)-(O-ethyl xanthate)-mediated RAFT polymerization of vinyl acetate[J].Journal of Applied Polymer Science,2012,125,2946-2955.DOI:10.1002/app.36233.
[14] Chen K P,Grant N,Liang L Y,et al.Synthesis of CO2-philic xanthate-oligo(vinyl acetate)-based hydrocarbon surfactants by RAFT polymerization and their applications on preparation of emulsion-templated materials[J].Macromolecules,2010,43:9355-9364.DOI:10.1021/ma101182f.
[15] Han S,Wang W,Jiao Z,et al.Solubility of vitamin E acetate in supercritical carbon dioxide:Measurement and correlation[J].Journal of Chemical & Engineering Data,2017,62(11):3854-3860.DOI:10.1021/acs.jced.7b00550.
[16] Lee H,Pack J W,Wang W X,et al.Synthesis and phase behavior of CO2-soluble hydrocarbon copolymer:poly(vinyl acetate-alt-dibutyl maleate) [J].Macromolecules,2010,43:2276-2282.DOI:10.1021/ma902505h.
[17] Wu Y,Zhang W,Zhang Z B.Initiator-chain transfer agent combo in the RAFT polymerization of styrene[J].Chemical Communications,2014,50:9722-9724.DOI:10.1039/c4cc03699a.