The uniform surface ion-imprinted resins for Zn2+ as the imprinting guest were prepared by emulsifier-free emulsion polymerization utilizing ally phenyl hydrogenphosphate as a functional comonomer. The Zn2+-imprinted ...The uniform surface ion-imprinted resins for Zn2+ as the imprinting guest were prepared by emulsifier-free emulsion polymerization utilizing ally phenyl hydrogenphosphate as a functional comonomer. The Zn2+-imprinted resin adsorbed Zn2+ much more effectively than did the unimprinted one. The selective feature of the surface imprinted resins to the template ions was demonstrated.展开更多
Stable high-solids-content acrylate emulsion were obtained with a nonionic polymerizable emulsifier allyloxy nonylphenoxy poly (ethyleneoxy) (10) ether (ANPEO10), and a conventional emulsifier OP-10 as a referen...Stable high-solids-content acrylate emulsion were obtained with a nonionic polymerizable emulsifier allyloxy nonylphenoxy poly (ethyleneoxy) (10) ether (ANPEO10), and a conventional emulsifier OP-10 as a reference sample. 1H NMR proves that the polymerizable emulsifier ANPEO10 has been incorporated into the resulted acrylate polymers. TEM demonstrates that there are some differences in the particle morphologies. AFM proves that the polymerizable emulsifier ANPEO10 migrating to the surface of the emulsion film was much less than the conventional emulsifier OP-10. The polymerizable emulsifier ANPEO10 can enhance the adhesion with glass plate compared to the conventional emulsifier. Furthermore, with increasing amount of emulsifier, the surface free energy of the films first decreased and then increased, and the adhesion with glass plate is initially enhanced and then attenuated. The water-resistance and solvent-resistance of the films prepared by the polymerizable emulsifier ANPEO10 are superior to those prepared by the conventional emulsifier OP-10.展开更多
A series of new water-soluble bifunctional comonomers having both carboxyl and alkyl polyoxyethylene groups, such as sodium mono(ethyl polyoxyethylene) maleate (ZE series) with various molecular weights of polyoxyethy...A series of new water-soluble bifunctional comonomers having both carboxyl and alkyl polyoxyethylene groups, such as sodium mono(ethyl polyoxyethylene) maleate (ZE series) with various molecular weights of polyoxyethylene ethyl ether, were synthesized and characterized. The effects of the structural factor, the amount and feeding mode of the comonomers, the initiator concentration and polymerization temperature on the stability of emulsifier-free emulsion copolymerization of methyl methacrylate (MMA) and butyl acrylate (BA) in the presence of a small amount of ZE with potassium persulfate as initiator were investigated. Stable, almost monodispersed MMA/BA/ZE emulsifier-free latex particles were prepared.展开更多
In this article,AHPS(3-allyloxy-2-hydroxy-1-propanesulfonate salt) was synthesized to use in emulsifier-free emulsion polymerization of BA/BMA/MMA system for high solid content latexes.Storage stability,flow behavior ...In this article,AHPS(3-allyloxy-2-hydroxy-1-propanesulfonate salt) was synthesized to use in emulsifier-free emulsion polymerization of BA/BMA/MMA system for high solid content latexes.Storage stability,flow behavior of the latexes,morphology of the obtained latex particles,dynamic viscoelastic behavior,tensile strength and water resistance properties of the resulted copolymers were investigated.The experimental results show that with the addition of AHPS,stability of the emulsion is greatly improved that there appears no apparent precipitation during the polymerization and storage at room temperature for 6 months and at -10℃ for four months.Flow of the latexes follows the Bingham body laws,diameter of the latex particles is about 0.6μm,of which is larger than that of by conventional emulsion polymerization(0.12μm).In addition,not only water resistance of the copolymers obtained by emulsifier-free emulstion polymerization is greatly improved,but also tensile strength is obviously enhanced.展开更多
The effects of ionic emulsifier, sodium dodecylbenzene sulfate (SDBS), on the formation of the multihollow structures in sub-micron sized polymer particles produced by alkali/acid posttreatment were investigated. The ...The effects of ionic emulsifier, sodium dodecylbenzene sulfate (SDBS), on the formation of the multihollow structures in sub-micron sized polymer particles produced by alkali/acid posttreatment were investigated. The original latex particles with narrow size distribution were synthesized by a new sequence emulsifier-free/emulsifier emulsion copolymerization of styrene (St) and methacrylic acid (MAA). Results indicated that the pore size decreased and the pore number increased with the increase of SDBS amount, and the morphology of the posttreated latex particles was also significantly influenced by the introducing time of SDBS in the preparation of the original latex particles, and a suitable introducing time was 3 h of polymerization. (c) 2007 Cheng You Kan. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
The formation mechanism of monodisperse polymer latex particles in the emulsifier-free emulsion polymerizationof methyl methacrylate and butyl acrylate with potassium persulfate as initiator was investigated. A multi-...The formation mechanism of monodisperse polymer latex particles in the emulsifier-free emulsion polymerizationof methyl methacrylate and butyl acrylate with potassium persulfate as initiator was investigated. A multi-step formationmechanism for the monodisperse polymer particles was proposed. The nucleation mechanism is considered to be thecoagulation of the precursor particles by homogeneous nucleation when the primary particles reach a critical size with highsurface charge density and sufficient stability. It had been proved by a special experiment that the early latex particles formedby the coagulation were stable. The primary particles grow by absorbing monomers and radicals in the polymerization systemand then become colloidally unstable again due to the understandable decrease of particle surface charge density, which leadsto the aggregation of the growing particles and the formation of larger latex pedicles therefrom. Aner the nucleation period,the preferential aggregation of the smaller particles in the propagation process leads to the change of the particles towards auniform size and narrower particle size distribution. The coexistence and competition of homogeneous nucleation,coagulation, propagation and aggregation result in the increase of the polydispersity index (U = D_(43)/D_(10)) in the first Stage,then its decrease in the later stage because of the competition of propagation and aggregation, and the gradual formation ofthe monodisperse particles.展开更多
The solubility of initiator determines its distribution and the roles played in emulsion polymerization as well as the final products, but this is still lack of systematic investigation. The present work focuses on th...The solubility of initiator determines its distribution and the roles played in emulsion polymerization as well as the final products, but this is still lack of systematic investigation. The present work focuses on this issue by comparing the kinetic behaviors and product properties of styrene emulsion polymerization initiated by 2,2-azoisobutyronitrile(AIBN) and potassium persulphate(KPS).Compared to KPS-initiated emulsion polymerization, the AIBN-initiated polymerization was found to be insensitive to the type of emulsifier, and have high polymerization rate as well as narrow molecular weight distribution and particle size distribution. This result indicates the effective free radicals are generated in micelles or colloids, which could decrease the proportion of homogeneous nucleation and make the process and product more controllable. As a consequence, there is a linear relationship between molecular weight of product and AIBN concentration in lg-lg coordinate. It provided a reference for the preparation of latexes with specified molecular weight and supported the possibility of the coexistence of multiple free radicals in one micelle or colloid when using oil-soluble initiator.展开更多
The amino poly-siloxane was modified with self-made polyether silicones by the crafts of emulsion polymerization. We studied the emulsifier, the dosage of emulsifier initiator, polyether/silane coupling agent, pH valu...The amino poly-siloxane was modified with self-made polyether silicones by the crafts of emulsion polymerization. We studied the emulsifier, the dosage of emulsifier initiator, polyether/silane coupling agent, pH value. There are some results of the research indicated in the following. First, there are many factors for the hydrophilic amino-silicone softener both on the polymerization process and the performance, such as the proportion and amount of emulsifier, initiator dosage, the mass ratio of the polyether and hydrogen silicone oil, the choice of silicone coupling agent, and the ratio and dosage of polyether silicones silane coupling agent. Second, the amount of hydrogen of the hydrogen silicones and the choice of catalyst are the key points on the synthesis of polyether silicones. The amount of hydrogen should be low and the catalyst must be economical and efficient and its introduction should be small and times, other more the holding time is not too long. The next one is that, in the process of hydrolysis of silane coupling agent, we need some acid to adjust pH value, or they will be broken down. The most important one but not the last is that the epoxy group can improve the products low-temperature supple and the persistence of the finishing fabric, furthermore it can reduce yellowing and has a good stability of the inorganic salt, however, it will be destroyed if the reaction temperature for epoxy is too high. What’s more, it is very economical and environmental that the process of emulsion is simple and with less emulsifier.展开更多
The behaviour of water soluble and monomer soluble inhibitors in emulsion polymerization of monomersfollowing Case Ⅱ kinetics(e.g.styrene)has been investigated.Experimental studies reveal that inhibitors canhave an a...The behaviour of water soluble and monomer soluble inhibitors in emulsion polymerization of monomersfollowing Case Ⅱ kinetics(e.g.styrene)has been investigated.Experimental studies reveal that inhibitors canhave an appreciable effect on both polymer particle nucleation and growth.A mathematical model showingthese effects has been developed and simulation studies have been done.The simulation results imply that theconsequences of these effects of monomer soluble inhibitors for industrial emulsion polymerization may be quiteserious.展开更多
基金Financial supported by the Natural Science Foundation of China (No: 50003006)
文摘The uniform surface ion-imprinted resins for Zn2+ as the imprinting guest were prepared by emulsifier-free emulsion polymerization utilizing ally phenyl hydrogenphosphate as a functional comonomer. The Zn2+-imprinted resin adsorbed Zn2+ much more effectively than did the unimprinted one. The selective feature of the surface imprinted resins to the template ions was demonstrated.
基金Funded by Ministry of Education (No.2006-KL-008),and Qingxin Hanerchem Chemical Technology Co,Ltd.
文摘Stable high-solids-content acrylate emulsion were obtained with a nonionic polymerizable emulsifier allyloxy nonylphenoxy poly (ethyleneoxy) (10) ether (ANPEO10), and a conventional emulsifier OP-10 as a reference sample. 1H NMR proves that the polymerizable emulsifier ANPEO10 has been incorporated into the resulted acrylate polymers. TEM demonstrates that there are some differences in the particle morphologies. AFM proves that the polymerizable emulsifier ANPEO10 migrating to the surface of the emulsion film was much less than the conventional emulsifier OP-10. The polymerizable emulsifier ANPEO10 can enhance the adhesion with glass plate compared to the conventional emulsifier. Furthermore, with increasing amount of emulsifier, the surface free energy of the films first decreased and then increased, and the adhesion with glass plate is initially enhanced and then attenuated. The water-resistance and solvent-resistance of the films prepared by the polymerizable emulsifier ANPEO10 are superior to those prepared by the conventional emulsifier OP-10.
文摘A series of new water-soluble bifunctional comonomers having both carboxyl and alkyl polyoxyethylene groups, such as sodium mono(ethyl polyoxyethylene) maleate (ZE series) with various molecular weights of polyoxyethylene ethyl ether, were synthesized and characterized. The effects of the structural factor, the amount and feeding mode of the comonomers, the initiator concentration and polymerization temperature on the stability of emulsifier-free emulsion copolymerization of methyl methacrylate (MMA) and butyl acrylate (BA) in the presence of a small amount of ZE with potassium persulfate as initiator were investigated. Stable, almost monodispersed MMA/BA/ZE emulsifier-free latex particles were prepared.
文摘In this article,AHPS(3-allyloxy-2-hydroxy-1-propanesulfonate salt) was synthesized to use in emulsifier-free emulsion polymerization of BA/BMA/MMA system for high solid content latexes.Storage stability,flow behavior of the latexes,morphology of the obtained latex particles,dynamic viscoelastic behavior,tensile strength and water resistance properties of the resulted copolymers were investigated.The experimental results show that with the addition of AHPS,stability of the emulsion is greatly improved that there appears no apparent precipitation during the polymerization and storage at room temperature for 6 months and at -10℃ for four months.Flow of the latexes follows the Bingham body laws,diameter of the latex particles is about 0.6μm,of which is larger than that of by conventional emulsion polymerization(0.12μm).In addition,not only water resistance of the copolymers obtained by emulsifier-free emulstion polymerization is greatly improved,but also tensile strength is obviously enhanced.
文摘The effects of ionic emulsifier, sodium dodecylbenzene sulfate (SDBS), on the formation of the multihollow structures in sub-micron sized polymer particles produced by alkali/acid posttreatment were investigated. The original latex particles with narrow size distribution were synthesized by a new sequence emulsifier-free/emulsifier emulsion copolymerization of styrene (St) and methacrylic acid (MAA). Results indicated that the pore size decreased and the pore number increased with the increase of SDBS amount, and the morphology of the posttreated latex particles was also significantly influenced by the introducing time of SDBS in the preparation of the original latex particles, and a suitable introducing time was 3 h of polymerization. (c) 2007 Cheng You Kan. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
文摘The formation mechanism of monodisperse polymer latex particles in the emulsifier-free emulsion polymerizationof methyl methacrylate and butyl acrylate with potassium persulfate as initiator was investigated. A multi-step formationmechanism for the monodisperse polymer particles was proposed. The nucleation mechanism is considered to be thecoagulation of the precursor particles by homogeneous nucleation when the primary particles reach a critical size with highsurface charge density and sufficient stability. It had been proved by a special experiment that the early latex particles formedby the coagulation were stable. The primary particles grow by absorbing monomers and radicals in the polymerization systemand then become colloidally unstable again due to the understandable decrease of particle surface charge density, which leadsto the aggregation of the growing particles and the formation of larger latex pedicles therefrom. Aner the nucleation period,the preferential aggregation of the smaller particles in the propagation process leads to the change of the particles towards auniform size and narrower particle size distribution. The coexistence and competition of homogeneous nucleation,coagulation, propagation and aggregation result in the increase of the polydispersity index (U = D_(43)/D_(10)) in the first Stage,then its decrease in the later stage because of the competition of propagation and aggregation, and the gradual formation ofthe monodisperse particles.
基金the financial support of the National Natural Science Foundation of China(Nos.21422603 and U1662120)
文摘The solubility of initiator determines its distribution and the roles played in emulsion polymerization as well as the final products, but this is still lack of systematic investigation. The present work focuses on this issue by comparing the kinetic behaviors and product properties of styrene emulsion polymerization initiated by 2,2-azoisobutyronitrile(AIBN) and potassium persulphate(KPS).Compared to KPS-initiated emulsion polymerization, the AIBN-initiated polymerization was found to be insensitive to the type of emulsifier, and have high polymerization rate as well as narrow molecular weight distribution and particle size distribution. This result indicates the effective free radicals are generated in micelles or colloids, which could decrease the proportion of homogeneous nucleation and make the process and product more controllable. As a consequence, there is a linear relationship between molecular weight of product and AIBN concentration in lg-lg coordinate. It provided a reference for the preparation of latexes with specified molecular weight and supported the possibility of the coexistence of multiple free radicals in one micelle or colloid when using oil-soluble initiator.
文摘The amino poly-siloxane was modified with self-made polyether silicones by the crafts of emulsion polymerization. We studied the emulsifier, the dosage of emulsifier initiator, polyether/silane coupling agent, pH value. There are some results of the research indicated in the following. First, there are many factors for the hydrophilic amino-silicone softener both on the polymerization process and the performance, such as the proportion and amount of emulsifier, initiator dosage, the mass ratio of the polyether and hydrogen silicone oil, the choice of silicone coupling agent, and the ratio and dosage of polyether silicones silane coupling agent. Second, the amount of hydrogen of the hydrogen silicones and the choice of catalyst are the key points on the synthesis of polyether silicones. The amount of hydrogen should be low and the catalyst must be economical and efficient and its introduction should be small and times, other more the holding time is not too long. The next one is that, in the process of hydrolysis of silane coupling agent, we need some acid to adjust pH value, or they will be broken down. The most important one but not the last is that the epoxy group can improve the products low-temperature supple and the persistence of the finishing fabric, furthermore it can reduce yellowing and has a good stability of the inorganic salt, however, it will be destroyed if the reaction temperature for epoxy is too high. What’s more, it is very economical and environmental that the process of emulsion is simple and with less emulsifier.
文摘The behaviour of water soluble and monomer soluble inhibitors in emulsion polymerization of monomersfollowing Case Ⅱ kinetics(e.g.styrene)has been investigated.Experimental studies reveal that inhibitors canhave an appreciable effect on both polymer particle nucleation and growth.A mathematical model showingthese effects has been developed and simulation studies have been done.The simulation results imply that theconsequences of these effects of monomer soluble inhibitors for industrial emulsion polymerization may be quiteserious.