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有机硅改性丙烯酸酯微乳液的合成与表征 总被引:2,自引:1,他引:1
采用种子乳液聚合法,以有机硅微乳液为种子乳液,在其表面进行壳聚合,合成了核壳型有机硅改性丙烯酸酯微乳液。研究了交联单体以及有机硅种子乳液用量对硅丙微乳液性能的影响,并通过红外、核磁共振及差热分析等表征了共聚物的结构。结果表明:当引发剂用量为乳液总质量的0.4%、双丙酮丙烯酰胺为交联单体且用量为乳液总质量的3%、有机硅种子乳液用量为25%时,硅丙微乳液的单体转化率达95.53%,凝胶率小,乳胶粒粒径81.2 nm;与纯丙乳液相比,成膜性更好,玻璃化转变温度低3.7℃。 相似文献
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有机硅改性丙烯酸酯乳液的制备及表征 总被引:2,自引:0,他引:2
以γ-甲基丙烯酰氧丙基三甲氧基硅烷(KH-570)、八甲基环四硅氧烷(D4)、丙烯酸酯类单体为原料,制备了有机硅改性丙烯酸酯乳液.考察了乳化剂配比、有机硅用量对乳液及乳胶膜性能的影响,并用红外光谱、凝胶渗透色谱、透射电镜进行了表征.结果表明KH-570先与低聚体D4开环预聚,再与丙烯酸酯类单体进行自由基聚合,可得到有机硅改性丙烯酸酯乳液;当有机硅占单体总质量的9%,其中m(KH-570)∶m(D4)=1∶9,m(MS-1)∶m(AEO)=2∶1时,乳液的黏度、凝胶率和乳胶膜的硬度随有机硅用量的增加而增大,乳胶膜的吸水率则降低;乳胶粒表面光滑均一,呈规则的圆球状,平均粒径为100 nm,其重均摩尔质量Mw=1.75×104g/mol,摩尔质量分布Mw/Mn=1.3. 相似文献
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《有机硅材料》2003,17(5):40-40
有机硅改性丙烯酸乳液青岛科技大学的孙道兴等人以丙烯酸酯类单体、苯乙烯、羟基硅油、硅烷偶联剂A - 1 71为原料 ,OP - 1 0和十二烷基苯磺酸钠为乳化剂 ,过硫酸铵为引发剂 ,通过种子聚合法合成了硅丙乳液。当复合乳化剂的用量为单体质量的 6%、羟基硅油的用量为 1 2 %、A - 1 71的用量为 2 % ,反应温度为 75~ 85℃时 ,可得到耐候性高、附着力强、耐水性优良的硅丙乳液。有机硅 -丙烯酸酯乳液的聚合稳定性华南理工大学的周新华等人以过硫酸铵为引发剂、十二烷基二苯醚二磺酸钠和辛基酚聚氧乙烯 ( 4 0 )醚为复合乳化剂 ,采用种子聚合法合… 相似文献
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有机硅改性丙烯酸酯乳液的合成及性能研究 总被引:3,自引:0,他引:3
采用有机硅氧烷与丙烯酸酯单体共聚制备有机硅改性丙烯酸酯乳液,研究了有机硅单体用量、乳化剂配比和温度等因素对乳液的影响,并对涂膜性能进行了测试。研究结果表明,有机硅与丙烯酸酯单体能很好地聚合,且制备出的乳液性能优异,可以作为高性能外墙涂料的基体树脂。 相似文献
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核壳型聚硅氧烷改性丙烯酸酯乳液的合成与表征 总被引:1,自引:1,他引:1
以八甲基环四硅氧烷(D4)和四乙烯基四甲基环四硅氧烷(D4Vi)为有机硅单体,十二烷基苯磺酸(DBSA)为催化剂,采用预乳化半连续种子乳液聚合工艺,在核壳型丙烯酸酯乳液的合成过程中,通过壳层聚合阶段的接枝共聚反应引入聚有机硅氧烷,制备出核壳型聚有机硅氧烷改性丙烯酸酯乳液。考察了DBSA、D4Vi和D4用量对乳液和乳胶膜性能的影响,并借助透射电镜和全反射红外光谱仪进行了表征。结果表明:有机硅单体的加入可显著改善聚丙烯酸酯乳胶膜的耐水性,当DBSA、DV4i和D4的质量分数分别为2%、4%和15%时,乳胶膜的吸水率为4.7%,对水的接触角为84°,冲击强度为53 cm,弯曲强度为2 mm,铅笔硬度为H。 相似文献
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丙烯酸酯核壳乳液合成及涂料耐沾污性的研究 总被引:1,自引:0,他引:1
讨论了丙烯酸酯乳液核壳单体中软硬单体的比例、壳层中掺交联单体、有机硅单体以及核壳乳液聚合中可聚合乳化剂的用量对丙烯酸酯外墙涂料沾污性的影响。结果表明,在壳层中HEMA的掺量以1.5%、可聚合乳化剂用量以1%~2%、有机硅单体掺量以4%时,有利于丙烯酸酯核壳乳胶涂料耐沾污性的提高。 相似文献
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改性有机硅织物柔软剂的研究 总被引:6,自引:0,他引:6
采用乳液滴加法合成了酯基改性有机硅织物柔软剂,并对影响聚合的各种因素进行了讨论。结果表明,利用水溶性催化剂,含氢硅油与丙烯酸酯在80°C条件下进行乳液聚合,可得到性能稳定的有机硅复合乳液,其对织物具有很好的柔软整理效果。 相似文献
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改性聚醋酸乙烯酯乳液的合成及性能研究 总被引:4,自引:4,他引:0
聚醋酸乙烯酯(PVAc)作为常用的环保、安全型胶粘剂之一,具有许多优异的性能,但由于耐水性较差而限制了其使用范围。以含功能基团的有机硅单体和第三单体(丙烯酰胺)作为PVAc的改性剂,合成了一种性能优异的改性PVAc乳液胶粘剂;探讨了聚乙烯醇(PVA)类型、有机硅及第三单体用量对改性PVAc乳液性能的影响。研究结果表明,共聚反应的优选条件为w(引发剂)=0.45%(相对于总体系而言),w(有机硅)=2%~4%(相对于VAc单体而言),m(PVA-1799)∶m(PVA-1788)=1∶1;另外,通过调节m(PVA-1799)∶m(PVA-1788)比例及丙烯酰胺的用量,可以改变改性PVAc乳液的黏度。 相似文献
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高阻燃性有机硅改性丙烯酸树脂的合成研究 总被引:4,自引:0,他引:4
以苯乙烯、丙烯酸酯类单体和硅油大单体为聚合单体,加入改性后的纳米双羟基复合金属氧化物、乳化剂等进行乳液聚合制备有机硅改性丙烯酸树脂乳液,制成的皮革涂饰剂具有优异的阻燃性,其综合性能明显提高。 相似文献
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阳离子聚合物乳液的合成及其在涂料染色中的应用 总被引:1,自引:0,他引:1
采用无皂乳液聚合的方法,选择合适的阳离子单体和引发剂,合成了稳定的阳离子型聚合物乳液.分析了软单体BA、硬单体St、阳离子单体DMC、引发荆APS用量和搅拌速度等因素对乳液粒径及稳定性的影响.结果表明,当阳离子单体、软、硬单体用量分别为13.14%、6.18%和2.32%,引发剂用量为0.5%,搅拌速度为250 r/min时,合成的乳液粒径为383.3 nm,具有较好的稳定性.应用于涂料染色织物,阳离子聚合物乳液具有比商品粘合剂高的干湿摩擦牢度.电子显微镜的观察结果说明,阳离子乳液能够在织物表面形成更完整均匀的聚合物薄膜. 相似文献
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以苯乙烯(St)和对氯甲基苯乙烯(VBC)为共聚单体,过硫酸钾(KPS)为引发剂,十二烷基苯磺酸钠(SDBS)为乳化剂,采用乳液聚合法制备了富含氯甲基的苯乙烯-对氯甲基苯乙烯共聚物功能微球。采用红外光谱(FT-IR)、扫描电镜(SEM)、激光粒度仪和X射线光电子能谱(XPS)对样品进行表征,研究了乳化剂用量、单体用量、引发剂用量、反应时间、反应温度等因素对微球粒径、乳液转化率的影响。结果表明,产物微球粒径均一,表面光滑、富含氯甲基功能基团,采用此方法可以制备粒径在100~250 nm的功能高分子微球。 相似文献
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Summary Stable organosilicon-acrylate copolymer latexes with high silicon content were prepared by seeded semibatch emulsion polymerization
of butyl acrylate (BA), methyl methacrylate (MMA) with a novel branched organosilicon monomer 3-methacryloxypropyl tris(trimethylsiloxy)
silane (MPTS). Monomer conversion, evolution of the particle size and its distribution were monitored by dynamic light scattering.
The effects of MPTS on the polymerization kinetics, the nucleation mechanism and properties of latex were investigated. The
results indicated that, in addition to micellar nucleation, a coagulative nucleation step was also observed as a result of
the addition of the organosilicon monomer, accordingly, the particle number of the silicon-acrylate latexes increased, the
average particle diameter decreased and the polymerization rate accordingly increased compared to those of the acrylate latexes
without organosilicon monomer. Moreover, the particle size distribution presented bimodal curves, which indicated that there
were large particles formed at an early stage. However, the particle size distribution curves became monomodal at the later
stage, and the final latex shows a narrow particle size distribution. It was found that the properties of latex and latex
film were obviously influenced by MPTS content. With increasing MPTS content, latex film glass transition temperature and
water absorption ratio decreased, the degradation temperature and water contact angle were increased. Hence, the resulting
latex films containing MPTS showed lower glass transition temperature and excellent water-resistance, which probably due to
the incorporation of the bulky branched hydrophobic group of MPTS into the copolymer chains. 相似文献
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J. ChudejI. Capek 《Polymer》2002,43(5):1681-1690
Batch emulsion polymerization of styrene initiated by an oil-soluble initiator and stabilized by non-ionic emulsifier (Tween 20) has been investigated. The rate of polymerization vs. conversion curve shows the two non-stationary rate intervals typical for the non-stationary-state polymerization. This behavior is a result of the continuous particle nucleation and the decrease of monomer concentration at the reaction loci with increasing conversion. The initial increase of the polymerization rate is attributed to the increase of particle number and the polymerization proceeding under the monomer-saturated condition—the Winsor I-like (micro)emulsion polymerization. The decrease of the polymerization rate is the result of the depressed transfer of monomer from the monomer reservoir to the reaction loci. Above 50 °C the monomer emulsion separates into two phases: the upper transparent monomer phase and the lower blue colored (microemulsion) phase. The polymerization mixture consists of the microdroplets (act as the reaction loci) and large degradable monomer droplets (act as the reservoir monomer and emulsifier). The continuous release of emulsifier from the monomer phase and the microdroplets induce the continuous particle nucleation up to high conversion. The initial formation of large particles results from the agglomeration of unstable growing particles and monomer droplets. The size of large (highly monomer-swollen) particles decreases with conversion and they merge with the growing particles at ca. 40-50% conversion. The coarse initial emulsion transformed during polymerization to the fine (semitransparent) polymer emulsion as a result of the continuous particle nucleation, the shrinking of highly monomer-swollen polymer particles and the depletion of monomer droplets. The low overall activation energy of polymerization is mainly ascribed to the decreased barrier for entering radicals into the latex particles with increasing temperature. 相似文献
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支化型有机硅/丙烯酸酯共聚乳液的合成及其性能 总被引:1,自引:1,他引:1
采用种子半连续乳液聚合,以γ-甲基丙烯酰氧基丙基三甲氧基硅烷(MPS)为交联单体,以具有支化型大体积疏水基团的有机硅单体γ-甲基丙烯酰氧基丙基三(三甲基硅氧基)硅烷(MATS)为功能单体,与丙烯酸丁酯和甲基丙烯酸甲酯进行乳液共聚,合成了稳定的交联型高硅含量硅丙乳液。对乳液聚合过程及聚合物膜性能的测试结果表明,随聚合体系中MATS用量由0增加到占单体总质量的10%,乳胶粒子的z-均粒径(Dz)由133.5 nm减小到123.7 nm,粒径多分散指数由1.150减小为1.131;聚合物膜的水表面接触角由61°增大到78,°48 h吸水率由5.9%降低为2.5%。 相似文献