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1.
乳化剂在含氟丙烯酸酯乳胶膜中的分布   总被引:2,自引:1,他引:1  
以阴离子型脂肪醇聚氧乙烯醚硫酸钠(AES)、阳离子型十六烷基-3-甲基氯化铵(CTAB)和反应型乳化剂烷基酰胺乙烯磺酸钠(DNS-86)作为乳化剂制备了三种甲基丙烯酸六氟丁酯和丙烯酸六氟丁酯共聚乳液(PF6MBA-co-F6BA)。通过表面能、原子力显微镜(AFM)和扫描电镜能谱分析(SEM-EDX)对乳胶膜进行表征,研究乳化剂在乳胶膜中的分布。发现阴离子和阳离子乳化剂在成膜过程中向膜-空气面迁移并发生富集,反应型乳化剂在膜中均匀分布;对含氟乳液进行透析后乳化剂的富集减少;经退火处理的乳胶膜的膜-空气面乳化剂富集现象消失。  相似文献   

2.
提出了交联体系中复合乳胶粒子的简单演化模型,即链引发→簇生成→簇增长→簇融合→成核。并以聚硅氧烷/聚丙烯酸酯体系为例进行了初步验证。结果表明,复合乳胶粒子的形成过程与假设的演化模型基本吻合。  相似文献   

3.
氟树脂/聚丙烯酸酯胶乳型互穿网络的合成   总被引:4,自引:0,他引:4  
采用原位聚合和互穿网络的方法,以氟树脂乳液作种子乳液,氟碳乳化剂和碳氢乳化剂为复配乳化剂,合成了聚丙烯酸酯和氟树脂胶乳型互穿网络聚合物(LIPN),所合成的乳液稳定性良好。通过对聚合物的微观形态、动态机械力学性能和接触角的分析,表明用此方法乳液聚合,可以较好地改善两种树脂的相容性,聚合物的表面能有了较大的下降。  相似文献   

4.
在甲基丙烯酰氧丙基三甲氧基硅烷存在下,以交联的聚硅氧烷为种子,丙烯酸酯单体为第二单体,偶氮二异丁腈为引发剂,分别采用间歇法、溶胀法和半连续法制备了聚硅氧烷/聚丙烯酸酯复合乳液。采用透射电子显微镜对乳胶粒子形态进行了表征,发现乳液中形成了以聚丙烯酸酯为核、聚硅氧烷为壳的反相核壳结构乳胶粒子;放置90天后,乳胶粒子的形态未发生翻转;将复合乳液破乳后分析,聚合物凝胶量达到96%以上,说明聚合体系交联很好。  相似文献   

5.
Self crosslinking fluorinated acrylic latex (SCLFAL) has been successfully prepared via starved seeded semibatch emulsion polymerization of butyl acrylate (BA), methyl methacrylate (MMA), 2‐(perfluoro‐(1,1‐bisisopropyl)‐2‐propenyl)oxyethyl methacrylate (POMA), and N‐methylolacrylamide (NMA). The resultant SCLFAL is characterized by Fourier transform infrared (FTIR) spectrometry and nuclear magnetic resonance (NMR). Influences of the added amount of NMA on the crosslinking degree, contact angle, particle size, and glass transition temperature (Tg) of the film are investigated. Results show that the crosslinking degree, contact angle, and Tg of the film can be improved when the moderate amount of NMA is introduced into the mixed monomers. However, the added amount of NMA has no marked effect on the particle size of SCLFAL. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

6.
Self-crosslinking fluorinated polyacrylate latexes based on butyl acrylate (BA), fluorine monomer octafluoropentyl methacrylate (OFPMA), self-crosslinking functional monomers acrylic acid (AA) and 2-hydroxyethyl acrylate (HEA) were synthesized by a monomer-starved seeded semi-continuous emulsion polymerization process. The latexes and their corresponding films were characterized by laser particle size analyser, Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), contact angle goniometer, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Results indicated that the particle size of the latexes and the gel content of the films were both independent of the amount of OFPMA employed. On the other hand, the particle size of the latexes decreased and the gel content of the films increased with the incorporation of AA and HEA as expected. Glass transition temperature (Tg) and the thermal stability of the copolymer were both improved gradually as OFPMA content increased. XPS, AFM and water contact angle measurement indicated that the fluoroalkyl groups had a tendency to enrich on the surface of the films. However, this enrichment of fluorine on the film surface was reduced after the introduction of self-crosslinking functional monomers into the system. Finally, the adhesive property of the latexes was evaluated for application as a pressure sensitive adhesive (PSA).  相似文献   

7.
通过乳液聚合法成功合成了纳米SiO2/聚丙烯酸酯杂化乳液。首先将纳米SiO2经过表面官能团化处理,使其表面含有活性官能团,然后经过乳液聚合使丙烯酸酯单体在纳米SiO2表面引发聚合,合成了具有核壳结构的纳米杂化乳液。采用透射电子显微镜(TEM)对乳液的微观结构进行了表征,并对胶膜进行了机械力学性能测试和表面润湿性能测试。结果表明纳米SiO2的表面官能团化处理改善了纳米粒子在乳液中的稳定性,当纳米SiO2质量分数为0 2%时,杂化乳液胶膜的拉伸强度和断裂伸长率同时达到最大值。其表面润湿性与SiO2质量分数有关,SiO2质量分数为0 5%时其杂化乳胶膜的接触角最大,耐水性最好。  相似文献   

8.
有机硅改性醋丙乳液的制备与表征   总被引:1,自引:0,他引:1  
杨蕊  王平华  刘春华 《粘接》2010,(12):62-64
采用半连续种子乳液聚合技术,以丙烯酸丁酯、醋酸乙烯酯和有机硅单体合成了有机硅改性醋丙乳液,并研究了有机硅含量、复合乳化剂配比、种子单体含量等对乳液聚合稳定性及乳液性能的影响。制备出的乳液稳定性良好,随着种子乳液单体含量的增加,乳胶粒粒径变小。  相似文献   

9.
A novel method to produce fluorine‐containing polyacrylate emulsion is presented. It is prepared by the copolymerization of n‐methyl methacrylate, n‐styrene, n‐butyl acrylate, and α‐methacrylic acid in the presence of swollen particles of PTFE. The structure and properties of the polymers are characterized by GPC, PSD, SEM, and XPS. The number‐average molar mass (Mn) 51,332, and the polydispersity 5.8688 are obtained. The mean diameter of latex particles is 300nm. Scanning electron microscopy reveals that particles of the emulsion are well dispersed. Meanwhile, the F1S content of the surface on the latex membrane is 8.99%. It is shown that the method of mixing micron and nanometer‐sized particles should be made the next step of research. It is also proved that inertia polymers can be used in emulsion property modification. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 558–562, 2006  相似文献   

10.
自交联封闭性乳液的合成与性能   总被引:2,自引:0,他引:2       下载免费PDF全文
罗春晖  瞿金清  陈焕钦 《化工学报》2009,60(7):1823-1830
以双丙酮丙烯酰胺(DAAM)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)和甲基丙烯酸(MAA)为共聚单体,采用半连续种子乳液聚合工艺合成自交联封闭性聚丙烯酸酯乳液(PAE),考察了DAAM和复合乳化剂对乳液聚合稳定性以及涂膜性能的影响。研究发现:随着DAAM含量的增加,乳液聚合稳定性下降,粒径增大,涂膜的耐介质性能和交联度提高,合适的DAAM加入量为总单体质量的3.0%,DAAM和己二酰肼(ADH)的最佳摩尔比为2∶1。采用SDBS+OP-10+OP-40为复合乳化剂体系,选用乳化剂的含量为2.35%,阴/非离子乳化剂质量比为1∶1.25;复合乳化剂在种子、核、壳比例为1.5∶1∶2,制备的乳液具有较好的聚合稳定性(乳液凝胶率低和单体转化率高),乳液耐电解质(钙离子)稳定性好,涂膜具有优异的封闭性。傅里叶红外光谱(FTIR)表明在涂膜形成过程中DAAM的酮羰基与ADH的酰肼基反应生成腙(C=N),TEM分析显示乳液的乳胶粒子呈核壳结构,TGA分析发现DAAM改性的PAE降低了涂膜的热稳定性。  相似文献   

11.
核-壳结构含氟丙烯酸酯乳液的合成与表征   总被引:13,自引:0,他引:13       下载免费PDF全文
A fluorine-containing polyacrylate copolymer emulsion was synthesized by a seed emulsion polymerization method, in which methyl methacrylate (MMA) and butyl acrylate (BA) were used as main monomers and hexafluorobutyl methacrylate (HFMA) as fluorine-containing monomer. The structure and properties were characterized by Fourier transform infrared spectrum (FT-IR), transmission electron microscopy (TEM), particle size analysis, X-ray photoelectron spectroscopy (XPS), contact angle (CA), differential scanning calorimetry (DSC) and thermogravimetry (TG) analysis. The FTIR and TEM results showed that HFMA was effectively involved in the emulsion copolymerization, and the formed emulsion particles had a core-shell structure and a narrow particle size distribution. XPS and CA analysis revealed that a gradient concentration of fluorine existed in the depth profile of fluorine-containing emulsion film which was richer in fluorine and more hydrophobic in one side. DSC and TG analysis also showed that a clear core-shell structure existed in the fluorine-containing emulsion particles, and their film showed higher thermal stability than that of fluorine-free emulsion.  相似文献   

12.
刘秉智  李文安 《应用化工》2007,36(2):205-206
以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、丙烯酸(AA)为单体,以十二烷基苯磺酸钠为乳化剂,当m(BA)∶m(MMA)∶m(AA)=33∶17∶1,通过乳液聚合制得丙烯酸酯类乳液,再加入填料及各种助剂,经过高速搅拌、均质而出料。并且讨论了乳化剂及引发剂用量对乳液聚合、乳液及涂料性能的影响。  相似文献   

13.
马丽 《精细化工》2011,28(9):915-919
在阴/非离子表面活性剂作用下,将甲基丙烯酸十二氟庚酯(DFMA)与丙烯酸月桂酯(LA)、甲基丙烯酸羟丙酯(HPMA)及γ-甲基丙烯酰氧基丙基三甲氧基硅烷(MPMS)在水相进行乳液共聚,合成了一种硅烷改性氟代聚丙烯酸酯(DLHM)乳液。用红外光谱(IR)、核磁共振氢谱(1HNMR)和透射电镜(TEM)等对DLHM的结构及乳液的物化性能进行了表征和测定。再将DLHM乳液制备成氟碳涂层,考察温度、乳液用量对涂层表面性能的影响。结果表明,DLHM乳液具有核壳结构、平均粒径为131 nm、Zeta电位为-24.09 mV。当固化温度为150℃、乳液用量为25 g时,所得涂层性能最佳,与水的接触角达128°,表现出良好的拒水效果。  相似文献   

14.
Functional poly[styrene‐co‐(2‐ethylhexyl acrylate)‐co‐(1,6‐hexanediol diacrylate)]/poly[(methyl methacrylate)‐co‐(butyl acrylate)‐co‐(methacrylic acid)‐co‐(diacetone acrylamide)] (PS/PA) semi‐interpenetrating polymer networks (semi‐LIPNs) containing ketone carboxyl groups were synthesized by two‐stage emulsion polymerization, and characterized by Fourier transform infrared, transmission electron microscopy, dynamic light scattering and DSC. A unique feature of the PS/PA semi‐LIPNs is their ability to crosslink and form thermosetting full‐IPN polymers through the reaction of ketone carboxyl and hydrazide in the course of film formation at ambient temperatures. Series of latex particles with various levels of crosslinking density in the PS and PA domain and varied composition of PS/PA LIPNs were obtained. The effects of the LIPN PS/PA composition and the level of crosslinking density in the PS and PA domain on film density, swell ratio, mechanical properties and contact angle with water were investigated. Maximum synergy effects obtained at around 50/50 (PS/PA) in terms of mechanical properties, density and contact angle with water indicate that the maximum degree of interpenetration is obtained at this composition. Copyright © 2006 Society of Chemical Industry  相似文献   

15.
黄森  肖新颜  潘季荣 《化工学报》2012,63(4):1301-1307
采用种子乳液聚合法,以聚氨酯(PU)乳液为种子(在聚合过程中为壳相),甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、甲基丙烯酸十二氟庚酯(DFMA)和γ-甲基丙烯酰氧丙基三甲氧基硅烷(KH-570)改性的纳米SiO2组成的混合物为核相,合成了具有核壳结构的纳米SiO2/聚氨酯-含氟丙烯酸酯(SiO2/FPUA)复合乳液。考察了纳米SiO2和DFMA用量对乳液聚合过程及乳胶膜性能的影响。通过傅里叶红外光谱(FT-IR)、接触角(CA)、透射电子显微镜(TEM)、热重(TG)、差示扫描量热仪(DSC)和力学性能测试(MPT)等表征乳液的结构形态、乳胶膜的表面性能和综合性能。结果表明:乳胶粒子呈现“反相核壳”结构,以聚丙烯酸酯(PA)相为核,PU相为壳;由于纳米SiO2和DFMA的协同作用,涂膜的疏水性和综合性能得到了较大的提高。  相似文献   

16.
高固含量阳离子聚丙烯酸酯乳液的制备   总被引:3,自引:0,他引:3  
采用种子预乳化半连续法制得具有高固含量的阳离子型聚丙烯酸酯乳液,其乳液固含量达到41%。研究了引发剂、反应性乳化剂、乳液的软硬单体配比与聚合温度对乳液聚合稳定性和乳液性能的影响。结果表明:在乳液聚合体系中,引发剂用量为0.5%,反应性乳化剂用量为0.5%,软硬单体配比(MMA/BA)为2.0:1,聚合温度为80℃时,制备的乳液具有良好的稳定性、最佳性能以及对木材良好的封油效果。  相似文献   

17.
抗菌性聚丙烯酸酯乳液的超声合成与表征   总被引:1,自引:0,他引:1  
熊金钰 《天津化工》2010,24(3):17-18
本文以银离子作为抗菌剂,采用超声辐射乳液聚合技术,合成了抗菌性P(MMA-BA-AA)胶乳,透射电镜的检测结果显示其乳胶粒的大小分布在50~120nm,抗菌性实验表明此胶乳的抑菌效果优良。  相似文献   

18.
聚丙烯酸酯的乳液聚合及其吸油性能研究   总被引:1,自引:0,他引:1  
以丙烯酸十二酯、丙烯酸丁酯等为原料,采用乳液聚合法合成了聚丙烯酸酯树脂。讨论了乳化剂、搅拌速度、反应温度对聚丙烯酸酯乳液性能的影响,考察了单体配比、引发剂用量、交联剂种类及用量、致孔剂用量等对聚丙烯酸酯树脂吸油性能的影响。发现当反应单体丙烯酸丁酯与丙烯酸十二酯的摩尔比为3∶1,交联剂二乙烯基苯用量为单体质量的2%,引发剂过硫酸铵用量为单体质量的2%,致孔剂乙酸乙酯用量为单体质量的50%时,合成的聚丙烯酸酯树脂对煤油、甲苯和CCl4的吸收率分别为7.12、18.10和33.39g·g-1,表现出良好的吸油性能。  相似文献   

19.
中空聚合物乳胶粒子的制备   总被引:5,自引:0,他引:5  
研究了在制备中空乳胶粒子的过程中,复合乳液(苯乙烯(St)-丙烯酸丁酯(BA)-甲基丙烯醛(MA))进行种子聚合时,St/BA的质量比和MA的用量对胶乳粒子的空径、粒径和表面羧基质量摩尔浓度的影响。实验结果表明,当St/BA的质量比为19,MA质量分数为单体的5.6%时,形成的乳胶粒子的空径最大。  相似文献   

20.
Latex interpenetrating polymer networks (LIPNs) have been prepared using a crosslinked polychloroprene latex as the seed emulsion, followed by the in situ polymerization of styrene, typically with a 10% divinyl benzene crosslinker. Polychloroprene–crosslinked polystyrene (XPS) ratios ranging from 70/30 to 40/60 were used, with the second monomer being added as a single aliquot rather than by “starvation” routes. The majority of the work has been conducted using the water‐soluble persulfate initiator method, which entails lengthy (∼ 6 h) polymerizations. To follow the development of microstructure, polymerizations were also stopped at 0.5, 1, and thence hourly intervals up to 6 h, so that any effect of time on shell and domains could be seen by transmission electron microscopy (TEM). Parallel studies using azo‐bis(isobutyronitrile) (AIBN) as initiator at the same temperature were conducted. Products were also studied, after staining, by TEM. For the persulfate initiator, domain structures predominated for the 70/30 ratio, but polystyrene‐rich shells are found in all cases, with increasing thickness as the chloroprene/styrene ratio was reduced. The styrene‐rich products (i.e., 40/60 Neoprene/XPS ratio) appear to have larger unstained domains suggesting phase separation. For the AIBN‐initiated styrene polymerization, shells are less evident, and where they exist, are both thinner and less continuously developed. Domain sizes are somewhat larger. This relatively hydrophobic initiator has caused polymerization predominately in the interior of each latex particle. The particle size distribution of the seed neoprene latex is broad and bimodal. As the LIPNs form, the larger diameter component increases and little evidence for fresh nucleation, in the form of small diameter particles, is seen. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 629–638, 1999  相似文献   

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