控压微波合成无皂高分子胶体粒子
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摘要
本文主要围绕“控压微波合成无皂高分子胶体粒子”的主题，利用自行设计的控压微波化学反应器进行实验，比较详细地讨论了在一定压力下微波场中进行的无皂乳液聚合。通过与常压微波辐照法和通常的水浴加热法进行比较，从共聚和均聚两种乳液聚合方式出发，借助于现代激光光散射技术对胶体粒子进行表征，讨论了无皂高分子胶体粒子的形成与组成、成核机理、胶体粒子的稳定性等方面的内容。发现在一定的条件下，在控压微波合成无皂高分子胶体粒子的成核过程中，与传统的成核机理有所不同。本研究为制备稳定的单分散高分子纳米粒子提供了有效的方法，为推广高分子纳米材料的产业化奠定了一定的基础。
通过无皂乳液聚合，合成了聚(苯乙烯-丙烯酰胺)、聚(苯乙烯-乙烯基吡咯烷酮)、聚(苯乙烯-甲基丙烯酸甲酯)、聚苯乙烯、聚甲基丙烯酸甲酯等胶乳粒子。通过比较它们的反应动力学、改变各种反应组分的用量、添加不同的有机溶剂以及改变反应的预设压力等一系列实验，我们得出的结论是，在利用控压微波合成法与常压微波辐照法进行无皂乳液聚合时，在不同的反应条件下，其成核机理是不同的，微波辐照法提高了反应速率，为生成更小尺寸、更稳定的单分散胶体粒子提供了条件。
对于常压微波辐照法，其成核机理与通常的无皂乳液聚合是一致的。而对于控压微波合成法来说，则情况要复杂些。当反应为两种单体共聚时，水溶性或在水中溶解度比较高的共聚单体加入时，会有一个“聚集”粒子的“解聚”过程，而且会形成粒径更小更稳
定的高分于纳米粒子；不过对于乙烯基毗咯烷酮作为共聚单体和苯
乙烯聚合时，因为其分子结构含有五圆环，从而具有一定的特殊
性，没有观察到“聚集”粒子的“解聚”过程，而且形成的胶体粒
子不仅粒径增大，稳定性也有所下降。在控压微波合成中，当反应
为一种单体的均聚时，我们发现参加均聚单体的水溶性将对成核历
程产生重要影响，对于油溶性单体来说，其成核机理与通常的无皂
乳液聚合中齐聚物胶束成核机理是一致的，而对于在水中溶解度比
较高的单体来说，其成核机理又会出现“聚集”粒于的“解聚”过
程，从而说明单体的性质对成核机理有重要影响。
此外，通过动态激光光散射和静态激光光散射的相结合，分析
聚苯乙烯胶体粒子，发现胶体粒子的分散性与聚合物高分子链的大
小及其分布没有直接的关系，也就是说，在微波辐照下的无皂乳液
聚合，虽然形成的高分子链大小不一，而且链的密度差别很大，但
它们在乳液中缠结在一起而形成的胶体粒子尺寸分布却具有单分散
性。
Having encircled the title of "Microwave Irradiation Synthesis Soap-less of Polymeric Particles at Expected Pressure", the article discussed detailedly soapless emulsion polymerization by microwave irradiation at a certain pressure with the microwave chemical reactor designed ourselves. With comparing microwave irradiation with a conventional heating, the formation and constitution of the soapless polymeric particles, and the mechanism of particle nucleation in polymerization, and the stability of particle and so on, have been widely discussed by using the laser light scattering (LLS) including emulsion polymerization of copolymer and homopolymer. It was found that the mechanism of particle nucleation in soapless emulsion polymerization by microwave irradiation under a certain pressure differed from the conventional methods. The works provide an effective way to prepare stably monodisperse polymeric nanoparticles and a base for improving industrialization of polymeric nanomaterials.
The lattices particles of poly(styrene- acrylamide ), poly(styrene-co-1-vinyl-2-pyrrolidone), poly(styrene- methyl methacrylate), polystyrene, and polymethylmethacrylate were prepared by using soapless emulsion polymerization. With comparing its reaction kinetics, the amounts of composition, adding the different organic solvents and changing the expected pressure, it is concluded that the different mechanism of particle nucleation would be operated when using microwave irradiation at an expected pressure or at a normal pressure at the different reaction condition. Microwave irradiation could be in favor of improving reaction
speed, creating smaller particles, and forming more stably and monodispersed polymeric particles.
The mechanism of particle nucleation of microwave irradiation at normal pressure is the same as the conventional emulsifier-free emulsion polymerization. However, it is rather complicated in microwave irradiation at an expected pressure. In copolymerization, when the monomer with water-solubility or relative high solubility in water was added in, the procession of soapless emulsion polymerization would have a course from "conglomeration particles" to "disassembly particles". And as a result of its, more smaller and stably polymeric nanoparticles would be created. It should be pointed out that just because the special structure of l-vinyl-2-pyrrolidone with the five-cirque, the same procession was not found, furthermore the hydrodynamic radius of the particle was increased and with a lower stability. So it is an exception in such a reaction condition. In homopolymerization by using microwave irradiation at an expected pressure, it was found that the water-solubility of monomer has an important effect upon the
procession of the particle nucleation. When the monomer is oil-solubility, the mechanism is as same as oligomer micell nucleation in conventional soapless emulsion polymerization. And when the monomer has certain solubility in water, the procession of particle nucleation shall appear the same course from "conglomeration particles" to "disassembly particles".
Moreover, by using a combination of static and dynamic laser light scattering, it was found that the distribution of colloid particle has not a obvious relation to the size and distribution of polymeric chain, that is to say, although with the different size of the polymeric chain, the colloid particle 's distribution is monodisperse.
通过无皂乳液聚合，合成了聚(苯乙烯-丙烯酰胺)、聚(苯乙烯-乙烯基吡咯烷酮)、聚(苯乙烯-甲基丙烯酸甲酯)、聚苯乙烯、聚甲基丙烯酸甲酯等胶乳粒子。通过比较它们的反应动力学、改变各种反应组分的用量、添加不同的有机溶剂以及改变反应的预设压力等一系列实验，我们得出的结论是，在利用控压微波合成法与常压微波辐照法进行无皂乳液聚合时，在不同的反应条件下，其成核机理是不同的，微波辐照法提高了反应速率，为生成更小尺寸、更稳定的单分散胶体粒子提供了条件。
对于常压微波辐照法，其成核机理与通常的无皂乳液聚合是一致的。而对于控压微波合成法来说，则情况要复杂些。当反应为两种单体共聚时，水溶性或在水中溶解度比较高的共聚单体加入时，会有一个“聚集”粒子的“解聚”过程，而且会形成粒径更小更稳
定的高分于纳米粒子；不过对于乙烯基毗咯烷酮作为共聚单体和苯
乙烯聚合时，因为其分子结构含有五圆环，从而具有一定的特殊
性，没有观察到“聚集”粒子的“解聚”过程，而且形成的胶体粒
子不仅粒径增大，稳定性也有所下降。在控压微波合成中，当反应
为一种单体的均聚时，我们发现参加均聚单体的水溶性将对成核历
程产生重要影响，对于油溶性单体来说，其成核机理与通常的无皂
乳液聚合中齐聚物胶束成核机理是一致的，而对于在水中溶解度比
较高的单体来说，其成核机理又会出现“聚集”粒于的“解聚”过
程，从而说明单体的性质对成核机理有重要影响。
此外，通过动态激光光散射和静态激光光散射的相结合，分析
聚苯乙烯胶体粒子，发现胶体粒子的分散性与聚合物高分子链的大
小及其分布没有直接的关系，也就是说，在微波辐照下的无皂乳液
聚合，虽然形成的高分子链大小不一，而且链的密度差别很大，但
它们在乳液中缠结在一起而形成的胶体粒子尺寸分布却具有单分散
性。
Having encircled the title of "Microwave Irradiation Synthesis Soap-less of Polymeric Particles at Expected Pressure", the article discussed detailedly soapless emulsion polymerization by microwave irradiation at a certain pressure with the microwave chemical reactor designed ourselves. With comparing microwave irradiation with a conventional heating, the formation and constitution of the soapless polymeric particles, and the mechanism of particle nucleation in polymerization, and the stability of particle and so on, have been widely discussed by using the laser light scattering (LLS) including emulsion polymerization of copolymer and homopolymer. It was found that the mechanism of particle nucleation in soapless emulsion polymerization by microwave irradiation under a certain pressure differed from the conventional methods. The works provide an effective way to prepare stably monodisperse polymeric nanoparticles and a base for improving industrialization of polymeric nanomaterials.
The lattices particles of poly(styrene- acrylamide ), poly(styrene-co-1-vinyl-2-pyrrolidone), poly(styrene- methyl methacrylate), polystyrene, and polymethylmethacrylate were prepared by using soapless emulsion polymerization. With comparing its reaction kinetics, the amounts of composition, adding the different organic solvents and changing the expected pressure, it is concluded that the different mechanism of particle nucleation would be operated when using microwave irradiation at an expected pressure or at a normal pressure at the different reaction condition. Microwave irradiation could be in favor of improving reaction
speed, creating smaller particles, and forming more stably and monodispersed polymeric particles.
The mechanism of particle nucleation of microwave irradiation at normal pressure is the same as the conventional emulsifier-free emulsion polymerization. However, it is rather complicated in microwave irradiation at an expected pressure. In copolymerization, when the monomer with water-solubility or relative high solubility in water was added in, the procession of soapless emulsion polymerization would have a course from "conglomeration particles" to "disassembly particles". And as a result of its, more smaller and stably polymeric nanoparticles would be created. It should be pointed out that just because the special structure of l-vinyl-2-pyrrolidone with the five-cirque, the same procession was not found, furthermore the hydrodynamic radius of the particle was increased and with a lower stability. So it is an exception in such a reaction condition. In homopolymerization by using microwave irradiation at an expected pressure, it was found that the water-solubility of monomer has an important effect upon the
procession of the particle nucleation. When the monomer is oil-solubility, the mechanism is as same as oligomer micell nucleation in conventional soapless emulsion polymerization. And when the monomer has certain solubility in water, the procession of particle nucleation shall appear the same course from "conglomeration particles" to "disassembly particles".
Moreover, by using a combination of static and dynamic laser light scattering, it was found that the distribution of colloid particle has not a obvious relation to the size and distribution of polymeric chain, that is to say, although with the different size of the polymeric chain, the colloid particle 's distribution is monodisperse.
引文
[1] 金钦汉，微波化学，北京：科学出版社，1999，10
[2] H.P. Broida, J.W. Moyer,J. Opt. Soc. Am.,1952,42:37
[3] A.Abu-Samra, J.S.Morris, S.R.Koirtyohann. Anal. Chem., 1975,47(8):1475
[4] R.Gedye,F.Smith,K.Westaway,et al.. Tetrahedron Lett., 1986,27(3):279
[5] J.W.Vanderhoff, 1969, U.S. 3432413, Chem. Abatr., 1969, 70,97422v
[6] M.Marry,D.Charlesworth,L.Swires,et al., J. Chem. Soc. Faraday Trans.,1994,90(13): 1999
[7] G.Gee, C.B.Davies, H.W.Melbille, Trans. Faraday Soc., 1939,35:1298
[8] T.Matsumoto,A.Ochi,Kobunshi kagaku,1965,22: 481
[9] W.D.Harkins,J. Chem. Phys., 1945,13:381
[10] W.D.Harkins,J.Am. Chem. Soc.,1947,69:1428
[11] W.V.Smith,E.H.Ewart,J. Chem. Phys.,1948,16:592
[12] R.M.Fitch,M.B.Prenosil,K.J.Sprick,J. Polym. Sci. Part C, 1969,27:95
[13] R.M.Fitch,Br. Polym.,J.,1973,5:347
[14] A.R. Goodall,M.C.Wilkinson,J. Hearn. J. Polym. Sci. Polym. Chem. Ed., 1977,15:2193
[15] Z.Song,W.P.Gary,J. Colloed Interface Sci.,1989, 128(2): 486
[16] Z.Song,W.P.Gary,J. Colloed Interface Sci.,1989, 128(2): 501
[17] 周其凤，胡汉杰，高分子化学，北京：化学工业出版社，2001，5
[18] 程时远，李建宗，纪庆绪，高分子通报，1991，3：129
[19]王群，府寿宽，于同隐，高分子通报，1996，3：141
[20]张立德，牟季美，纳米材料学，辽宁科技出版社，1994
[21]R. Feyman,Science, 1991,254(29):1300
[22]张立德，中国粉体技术，2000，6(1)：1
[23]薛群基，徐康，化学进展，2000，12(4)：431
[24]华中一，科学，2000，52(5)：6
[25]Wenmin Zhang,Jun Gao,Chi Wu, Macromolecules, 1997, 30:6388
[26]C. Wu,A. Z. Niu, L.M. Leung, J. Am. Chem. Soc.,1999, 121: 1954
[27]Z. H. Gan,T. F. Jim,M. Li,et al., Macromolecules,1999,32,590
[28]Z. H. Gan,T. F. Jim,C. Wu, Polymer,1999,40(8): 1961
[29]Y. Zhao, T. J. Hu, C. Wu, Polym. Sci. Polym. Phys. Ed., 1999, 37: 3288
[30]翟庆洲，裘式纶，肖丰收等，化学研究与应用，1998，10(3)：226
[31]汤勇铮，唐业仓，罗时忠等，物理化学学报，1998，14(7)：620
[32]翟慕衡，张文敏，盛恩宏等，物理化学学报，1999，15(8)：747
[33]张文敏，吴奇，魏涛等，物理化学学报，2000，16(2)：116]
[34]W. D. He,T. Lu, C.P. Pan, J. Appl. Polym. Polym. Sci., 2001, 80: 2455
[35]G. Z. Zhang, A. Z. Niu, S. F. Peng, et al., Laccounts of Chemical Research, 2001, 34:249
[2] H.P. Broida, J.W. Moyer,J. Opt. Soc. Am.,1952,42:37
[3] A.Abu-Samra, J.S.Morris, S.R.Koirtyohann. Anal. Chem., 1975,47(8):1475
[4] R.Gedye,F.Smith,K.Westaway,et al.. Tetrahedron Lett., 1986,27(3):279
[5] J.W.Vanderhoff, 1969, U.S. 3432413, Chem. Abatr., 1969, 70,97422v
[6] M.Marry,D.Charlesworth,L.Swires,et al., J. Chem. Soc. Faraday Trans.,1994,90(13): 1999
[7] G.Gee, C.B.Davies, H.W.Melbille, Trans. Faraday Soc., 1939,35:1298
[8] T.Matsumoto,A.Ochi,Kobunshi kagaku,1965,22: 481
[9] W.D.Harkins,J. Chem. Phys., 1945,13:381
[10] W.D.Harkins,J.Am. Chem. Soc.,1947,69:1428
[11] W.V.Smith,E.H.Ewart,J. Chem. Phys.,1948,16:592
[12] R.M.Fitch,M.B.Prenosil,K.J.Sprick,J. Polym. Sci. Part C, 1969,27:95
[13] R.M.Fitch,Br. Polym.,J.,1973,5:347
[14] A.R. Goodall,M.C.Wilkinson,J. Hearn. J. Polym. Sci. Polym. Chem. Ed., 1977,15:2193
[15] Z.Song,W.P.Gary,J. Colloed Interface Sci.,1989, 128(2): 486
[16] Z.Song,W.P.Gary,J. Colloed Interface Sci.,1989, 128(2): 501
[17] 周其凤，胡汉杰，高分子化学，北京：化学工业出版社，2001，5
[18] 程时远，李建宗，纪庆绪，高分子通报，1991，3：129
[19]王群，府寿宽，于同隐，高分子通报，1996，3：141
[20]张立德，牟季美，纳米材料学，辽宁科技出版社，1994
[21]R. Feyman,Science, 1991,254(29):1300
[22]张立德，中国粉体技术，2000，6(1)：1
[23]薛群基，徐康，化学进展，2000，12(4)：431
[24]华中一，科学，2000，52(5)：6
[25]Wenmin Zhang,Jun Gao,Chi Wu, Macromolecules, 1997, 30:6388
[26]C. Wu,A. Z. Niu, L.M. Leung, J. Am. Chem. Soc.,1999, 121: 1954
[27]Z. H. Gan,T. F. Jim,M. Li,et al., Macromolecules,1999,32,590
[28]Z. H. Gan,T. F. Jim,C. Wu, Polymer,1999,40(8): 1961
[29]Y. Zhao, T. J. Hu, C. Wu, Polym. Sci. Polym. Phys. Ed., 1999, 37: 3288
[30]翟庆洲，裘式纶，肖丰收等，化学研究与应用，1998，10(3)：226
[31]汤勇铮，唐业仓，罗时忠等，物理化学学报，1998，14(7)：620
[32]翟慕衡，张文敏，盛恩宏等，物理化学学报，1999，15(8)：747
[33]张文敏，吴奇，魏涛等，物理化学学报，2000，16(2)：116]
[34]W. D. He,T. Lu, C.P. Pan, J. Appl. Polym. Polym. Sci., 2001, 80: 2455
[35]G. Z. Zhang, A. Z. Niu, S. F. Peng, et al., Laccounts of Chemical Research, 2001, 34:249