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1.
A water-soluble hyperbranched polymer (WHBP), obtained from a second generation of hyperbranched polyester and maleic anhydride, was studied. Its effects on the properties of acrylic latexes, which were based on emulsion polymerization of butyl acrylate (BA), methyl methacrylate (MMA), acrylic acid (AA) and WHBP, and latex film were discussed. The characteristics of WHBP were determined by nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared (FTIR) and gel permeation chromatography (GPC). Particle size and morphology of latex particles were confirmed by dynamic light scattering (DLS) and transmission electron microscope (TEM). The investigation showed that WHBP could be used in emulsion polymerization, and that latex of poly(BA-MMA-WHBP) was more stable than that of poly(BA-MMA-AA). The hardness of latex film increased from 2B to HB when WHBP was used.  相似文献   

2.
合成了两种离子型表面活性单体(Surfmer)磺化-十二醇-烯丙基甘油-丁二酸酯钠盐(ZC-L)和磺化-十二醇-甲基丙烯酰甘油-丁二酸酯钠盐(ZD-L).着重研究了ZC-L的结构、表面张力行为、均聚及共聚能力.实验结果表明,不同Surfmer用量以及不同固含量下,MMA/BA/Surfmer,MMA/Surfmer及BA/Surfmer共聚乳液的表面张力较高,说明Surfmer已通过共聚结合在乳胶粒上,乳液中残留甚少.对MMA/BA体系,ZC-L的共聚性能比ZD-L好.  相似文献   

3.
种子乳液聚合法制备多孔乳胶粒   总被引:15,自引:0,他引:15  
用批量乳液聚合法制备了苯乙烯(St)———甲基丙烯酸甲酯(MMA)二元共聚种子乳液S1以及St MMA 丙烯酸(AA)三元共聚种子乳液S2,通过连续法无皂种子乳液聚合合成了一系列不同AA或MAA(甲基丙烯酸)含量的St、MMA三元共聚乳液.将所得复合胶乳进行碱/酸分步处理,得到具有多孔结构的乳胶粒.用透射电镜对胶粒形态进行了表征,考察了不饱和酸种类和用量、碱处理初始pH值及溶胀剂对胶粒成孔的影响.  相似文献   

4.
聚合物乳液作为基本成膜物已在建筑涂料、木器漆和工业漆方面得到了广泛应用 .由于多数小分子染料与成膜物及其他组分的相容性不够好 ,常常导致这类彩色的聚合物产品涂刷时色泽不均、涂膜在使用过程中易于变色等缺陷 .将生色基团键合到聚合物分子链上 ,可以从根本上克服因相容性差而引起的染料小分子的迁移 ,同时还可以显著提高产品的保光保色性能[1] .1 986年 ,BRIAN通过丙烯酸酯与含偶氮基烯类单体的乳液共聚合 ,制备出了一类可直接用于纺织印染行业的彩色乳液[2 ,3] .1 994年 ,SOSNOWSKI等制备出了用于荧光标签的乳液聚合…  相似文献   

5.
Stable core‐shell latex was synthesized by semicontinuous seeded emulsion polymerization with core monomers consisting of styrene (St), butyl acrylate (BA), and shell monomers consisting of methyl methacrylate (MMA), eutyl acrylate (EA), and methacrylic acid (MAA). The effects of compound emulsifier amount, mass ratio of anionic/nonionic emulsifier, and initiator amount on latex performance were investigated. By particle size analysis and transmission electron microscopy (TEM) observation, results suggest that final latex particles have clearly core shell structures.  相似文献   

6.
将超声技术引入到无皂乳液聚合方法中,在不加入任何引发剂和乳化剂的情况下,制备了丙烯酸丁酯(BA)/苯乙烯(St)/丙烯酰胺(AM)三元共聚纳米乳胶粒.研究了不同超声时间对单体转化率、乳胶粒粒径以及乳液粘度的影响.同时还探讨了超声无皂乳液聚合机理,认为AM在聚合过程中起到了引发和稳定的作用.TEM照片表明,乳胶粒直径大约在80nm左右,FTIR及DSC分析表明产物为三元共聚物,而不是共混物.  相似文献   

7.
符柳娃  苏嘉辉  严佳进  张婷  杨妍  刘晓暄 《应用化学》2018,35(12):1434-1441
选取十二烷基硫酸钠(SDS),辛基苯基聚氧乙烯醚(OP-10)为复合乳化剂,过硫酸钾(KPS)为引发剂,将2-(全氟己基)乙基甲基丙烯酸酯(PFM)与丙烯酸酯类单体采用预乳化-半连续种子乳液聚合法进行乳液共聚,再将羟基螺吡喃(SPOH)与乳液进行物理共混,制得光致变色含氟丙烯酸酯乳液。 通过多种表征手段研究丙烯酸正丁酯(n-BA)和甲基丙烯酸甲酯(MMA)软硬单体的质量比,SPOH的用量对聚合反应和乳胶膜性能的影响。 结果表明,加入含氟单体后乳胶膜与水、油的接触角提高,热稳定性提高;加入SPOH的质量分数为1.25%时,乳胶膜具有较好的光致变色性能。  相似文献   

8.
Fluorinated acrylate latex was successfully prepared by semi-continuous seeded emulsion polymerization of dodecafluoroheptyl methacrylate (DFMA) with butyl acrylate (BA), methyl methacrylate (MMA) initiated by potassium persulfate in the water. The resultant latexes and their films are characterized with Fourier transform infrared (FTIR) spectrometry, contact angle determinator, dynamic light scattering detector and surface tension determinator. Effect of different surfactants on colloidal and polymer properties of fluorinated acrylate latex was studied. Results show that the latex prepared with sodium dodecyl benzene sulfonate surfactant has the smallest particle size and contact angle but the moderate surface tension. The latex prepared with perfluorooctanesulfonic acid potassium surfactant has the smallest surface tension, moderate particle size but the biggest contact angle. The latex prepared with sodium 2-hydroxy-3-(methacryloyloxy) prop- ane-1-sulfonate surfactant has the biggest particle size and surface tension but moderate contact angle. In addition, the latex prepared with sodium 2-hydroxy-3-(methacryloyloxy) prop- ane-1-sulfonate has higher electrolyte stability.  相似文献   

9.
The influence of butyl acrylate (BA) and methyl methacrylate (MMA) on hydroxyl functionalized latexes was investigated. The hydrophobicity of the monomer feed was varied via the BA/MMA ratio. In addition to monitoring the effect of hydrophobic monomer feed on secondary nucleation, the polymerization kinetics and final latex properties were also obtained for comparison. Five different BA to MMA molar ratios were combined with five 2‐hydroxyethyl methacrylate (HEMA) concentrations (0, 10, 20, 30 and 40 mol% in monomer composition). All latexes were synthesized through seeded semibatch emulsion polymerization process. Particle size distributions and average particle sizes of the latexes were determined by dynamic light scattering (DLS) and qualitatively compared with transmission electron microscope (TEM) images. The BA to MMA ratio significantly influences the boundary HEMA concentration at which homogeneous secondary nucleation occurs. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2190–2202  相似文献   

10.
孔祥正 《高分子科学》2012,30(2):278-286
Cationic latexes were prepared through emulsion copolymerization of styrene(St) and butyl acrylate(BA) with a cationic surfactant,cetyl trimethyl ammonium bromide(CTAB).Latex properties,including particle size,size distribution,ζpotential,surface tension and monomer conversion,were determined for latexes prepared with different CTAB amounts. Evolution of these properties during emulsion polymerization was followed in order to understand the mechanism of the particles formation.Results showed that both particle size andζpotential were function of polymerization time and latex solids.Parallel emulsion polymerizations with cationic,anionic charged initiator and charge-free initiators were also carried out,the latex properties were determined at different polymerization time.All these results were attentively interpreted based on the mechanisms of emulsion polymerization,surfactant adsorption and latex particle stabilization.  相似文献   

11.
采用半连续种子乳液聚合法, 在十二烷基硫酸钠(SDS)/辛基苯基聚氧乙烯醚(TX-10)复合乳化剂的作用下, 合成了以丙烯酸丁酯(BA)为核, 以甲基丙烯酸甲酯(MMA)、甲基丙烯酸十二氟庚酯(DFHMA)、3-(甲基丙烯酰氧)丙基三甲氧基硅烷(MPTMS)和甲基三甲氧基硅烷(MTMS)为壳的核壳型含氟/硅丙烯酸酯聚合物乳液. 利用FTIR, TEM, SEM-EDX和DSC等手段对乳液组成、乳胶粒子结构、膜表面及断面形态等进行了表征, 讨论了氟/硅含量对聚合物膜性能的影响. 结果表明, 核-壳粒子尺寸为20~30 nm, 乳液膜的性能与膜表面氟和硅的含量及相容性有较大的相关性, 当m(氟)∶m(硅单体)=3∶1时, 形成的膜均匀透明, 吸水率较低, 尺寸稳定性较好.  相似文献   

12.
Alkali-soluble copolymer (butyl acrylate/acrylic acid) was synthesized via solution polymerization and used as the emulsifier to prepare acrylic resin for leather finishing agent. The influence of the synthetic conditions, such as the contents of acrylic acid and the initiator types on the properties of P(BA/AA) was investigated in detail. Fourier Transform Infrared Spectrometer (FTIR) indicated that the polymerization reaction of P(BA/AA) was complete without “CC” absorption peak. Differential Scanning Calorimeters (DSC) analysis confirmed that the glass transition temperature (Tg) of P(BA/AA) was −44 °C, Transmission Electron microscope (TEM) indicated that the copolymer latex particles dispersed evenly and were less than 100 nm. Moreover, in contrast to acrylic resin prepared with sodium dodecylsulfate (SDS) and alkylphenol ethoxylates (OP-10) as the emulsifiers, the applied properties of light leather finished by acrylic resin in use of P(BA/AA) as the emulsifier were measured: The air permeability increased by 18.5% as well as the water-resistance by 28.08% and the wet rub fastness by half class, respectively.  相似文献   

13.
The seeded semicontinuous emulsion multi-copolymerization of butyl acrylate (BA),2-ethylhexyl acrylate (2EHA), methyl methacrylate (MMA), 2-hydroxyl propyl acrylate(HOPA) and acrylic acid (AA) was used to prepare the acrylic latexes with high-solidcontent. The effects of monomer emulsion feed rates (R_a) and (R/E)_E values, the ratio ofemulsifier amount between the initial charge (R) and the addition monomer emulsion (E),on the polymerization reaction features, the viscosities, surface tensions,particle sizes andparticle sizes distributions of latexes,T_g and the insoluble fractions of films, the 180° peelstrength, tack and holding power of pressure-sensitive adhesive (PSA) tapes, preparedfrom the latexes, were studied. Experimental study shows that the grafting and cross-linking fraction in the PSA tapes must be controlled within a suitable range to keep thebalance of the 180° peel strength, tack and holding power.  相似文献   

14.
P(BA-EHA)/PVC复合胶乳的制备及表征   总被引:6,自引:0,他引:6  
采用乳液聚合法合成了丙烯酸丁酯与丙烯酸 2 乙基己酯交联共聚物 [P(BA EHA) ]乳液 ,以P(BA EHA)乳液为种子通过与氯乙烯 (VC)聚合制备了P(BA EHA) PVC复合胶乳 .考察了P(BA EHA)乳液用量对复合胶乳粒径及其材料力学性能的影响 ,借助透射电镜 (TEM)、扫描电镜 (SEM)和动态力学分析 (DMA)等手段对复合胶乳粒子及其所制材料的形态结构进行了表征 .DMA研究结果表明 ,橡胶相P(BA EHA)与基体PVC间相容性得到了良好改善 .随着P(BA EHA)含量的增加 ,低温区材料的力学损耗峰较纯聚氯乙烯增强 ,且峰位逐渐向高温区移动 .TEM照片显示 ,复合胶乳粒子具有清晰的核壳结构 ;P(BA EHA)非常均匀地分散在PVC中 ,两相界面模糊 .由SEM照片可见 ,材料缺口断面表现为很好的韧性断裂 .含 4 2 %P(BA EHA)材料的缺口抗冲强度是PVC的 11倍 ,断裂伸长率较PVC提高近两倍 .  相似文献   

15.
研究了ZC-L,ZD-L等表面活性单体存在下,MMA,BA和MMA/BA乳液聚合的稳定性,制得了不含游离乳化剂,固含量在40%以上RMMA,PBA以及P(MMA/BA)稳定乳液。  相似文献   

16.
1.INTRODUCTIONSince1980,agreatdealofresearchinteresthasbeendevotedtomicroemulsionpolymerization[1~10].Amicroemulsionmaybedefinedasthermodynamicallystableandopticallytransparentdispersioncomposedbywater,oilandsurfactant;inmanycasesacosurfactantisrequired.Microemulsionpolymerizationprocesscanyieldstablepolymerlatexeswithparticlesizeofabout10nmto100nm.However,therearetwomajordrawbacks,whichhavelimitedtheapplicationsofmicroemulsionpolymerization:(1)highsurfactantconcentration(upto20wt.%ofthet…  相似文献   

17.
丙烯酸酯纳米乳液的制备与表征   总被引:4,自引:0,他引:4  
将甲基丙烯酸羟乙酯(HEMA)与甲基丙烯酸(MAA)或丙烯酸(AA)用作甲基丙烯酸甲酯(MMA)/丙烯酸丁酯(BA)乳液聚合体系的反应性助乳化剂,采用一种改进的微乳液聚合方法,合成了高单体/乳化剂比例(大于40:1)的聚丙烯酸酯纳米乳液.讨论了引发剂、乳化剂、助乳化别对乳胶粒大小和胶膜吸水率的影响,并对乳液的流体力学行为,共聚物的拉伸行为及耐水性等进行了研究.  相似文献   

18.
A series of carboxylated acrylate copolymer latexes were prepared via two different emulsion polymerization technologies with different carboxylic‐group distribution and morphologies. The effects of the emulsifier, the initiator, and the carboxylic monomers [acrylic acid (AA) or monobutyl itaconate (MBI)] on the total conversion of the monomers and the properties of acrylate latexes and films have been investigated. The distribution of carboxylic groups (?COOH) measured by conductometric titration shows that the concentration of surface –COOH (Cs) and embedded –COOH (Cb) both increase with the increase of the amount of carboxylic monomers. For the latexes containing AA, –COOH tends to distribute on the surface of latex particles and in the aqueous phase, whereas –COOH tends to concentrate inside the core of latex particles for the latexes containing MBI. Transmission electron microscopy demonstrates that the latex particles are regular with narrow size distribution and have significant differences in morphologies when different carboxylic monomers and polymerization technologies were used. The stability of latex is satisfactory through the results of common stability and zeta potential tests. Moreover, the water absorption and contact angle experiment tests also revealed that the water resistance of the latex films is good. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

19.
功能单体α-烯烃磺酸钠用于无皂乳液共聚合   总被引:3,自引:0,他引:3  
用工业原料α-烯烃磺酸钠(AOS)作为功能单体与甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)进行了乳液共聚合,通过测定AOS与MAA的竞聚率,确定了适宜的聚合方式为连续加料法.使用5%AOS制备了高固含量(>60%)的胶乳,并与用十二烷基硫酸钠(SDS)作乳化剂时该体系的乳液共聚合进行了比较.AOS是影响乳液稳定性和胶粒大小的主要因素,当AOS含量为单体总质量的1%时可以得到固含量大于40%粒径小于100 nm的乳液;当AOS含量为5%时可以得到固含量大于60%的乳液.两种情况下胶粒粒径分散性均较窄,明显优于同样条件下用SDS制备的胶乳.使用1%AOS制得的胶乳静置1年后粒径及其分布基本保持不变.  相似文献   

20.
New polymer latexes bearing saccharide moieties on the particle surface were synthesized by using a water‐soluble sugar monomer, such as 1‐deoxy‐1‐methacryl‐amido‐D ‐glucitol, (MAG). All the latexes were prepared by a two‐stage emulsion polymerization technique. In the first step, the core was prepared with butyl acrylate (BA) and styrene (St). In the second step, the seed latex was polymerized with ethyl acrylate (EA) and MAG. The influence of a bifunctional monomer such as allyl methacrylate (ALMA), introduced at various concentrations, on the final latexes morphologies and properties was investigated. It was found that the latex particles exhibit a core‐shell structure. The mass balance of MAG showed that the main part of the sugar moiety is on the shell layer. The molecular properties, such as structure, composition, and molecular weight, were determined by elemental analysis, 1H‐ and 13CNMR spectroscopy. Colloidal (particle size and their distributions), thermal, and rheological properties were also studied. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

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