光致变色含氟丙烯酸酯涂层的制备及性能

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。     

阳离子无皂含氟丙烯酸酯的合成与表面性能

在合成甲基丙烯酸全氟辛酰氧基乙酯(FA)基础上,用半连续法制备了无皂阳离子含氟丙烯酸酯乳液。当乳液的粒径在100~200 nm、ζ电位大于40 mV时,乳液较稳定。阳离子亲水单体甲基丙烯酰氧乙基三甲基氯化铵(DMC)在含氟丙烯酸酯中质量分数为0.10~0.18、固含量小于20%时乳液的稳定性好,且随DMC含量的增加稳定性提高;含氟丙烯酸酯乳胶膜的附着力与耐磨性好,乳胶膜的透湿率随DMC的增加而增加。随热处理温度的提高,膜表面自由能下降;经160℃热处理后膜发生了交联,表面自由能为18 mN/m,与聚四氟乙烯(PTFE)的表面能相近,DMC含量对膜表面自由能影响不大。XPS分析也表明膜表面氟含量随热处理温度的提高而增加。     

氟代丙烯酸酯三元共聚物细乳液的合成与表征

在低乳化剂用量和不加助乳化剂的条件下,采用细乳液聚合方法,合成了平均粒径在110～150nm的氟代丙烯酸酯(FA)、甲基丙烯酸甲酯(MMA)及甲基丙烯酸丁酯(BMA)三元共聚物乳液.利用GPC,FTIR及¹HNMR谱表征了共聚物分子量和结构组成,采用激光光散射法研究了聚合过程中粒径变化规律,通过接触角方法对共聚物表面性能进行了表征.结果表明,油溶性引发剂AIBN引发FA-MMA-BMA三元细乳液共聚合的主要成核场所为单体液滴.即每个单体液滴都是一个独立的微型反应器,可避免因为单体水溶性的差异而使共聚组成产生漂移.细乳液聚合合成含氟共聚物乳液的分子量分布窄(1.3～1.5),乳液稳定性能好,共聚物在低含氟量下即表现出优异的疏水疏油性能.     

亲水单体对聚氨酯-含氟丙烯酸酯复合乳液颗粒和表面性能的影响

为了提高聚氨酯-丙烯酸酯聚合物的耐水性和耐溶剂性, 将N-甲基二乙醇胺(MDEA)扩链的交联聚氨酯丙酮溶液作为反应介质, 以苯乙烯、丙烯酸丁酯、含氟丙烯酸酯(FA)为单体, 过氧化苯甲酰为引发剂, 通过溶液聚合相转化法制得新型阳离子聚氨酯-含氟丙烯酸酯复合乳液. 研究了MDEA对聚合物水分散液的乳胶粒径、Zeta电位以及乳胶膜表面性能的影响, 并用FTIR, TEM对聚合物的结构和乳胶粒形态进行了表征. 结果表明, MDEA的添加利于降低乳胶粒径, 但对乳胶膜的疏水性能有不利影响, 当MDEA的质量分数为13.15%时, FPUA乳胶粒的形态呈球形, 粒径约为253 nm, 乳胶膜的表面自由能低于25.1 mJ/m², 接触角衰减速率约为0.38 (º)/min. 另外, 乳胶膜的高温处理能够使表面自由能降低11.5%以上.     

含氟共聚物的制备及其对古砂岩的保护研究

本文选用丙烯酸丁酯(BA)和甲基丙烯酸甲酯(MMA)为非含氟单体,甲基丙烯酸十二氟庚酯(DFHM,C11H8O2F12)为含氟单体,分别获得了含氟丙烯酸酯共聚物乳液(BA/MMA/DFHM)和含氟丙烯酸酯共聚物溶液[P(BA-MMA-co-DFHM)],并分别选用毛细吸收法、喷涂法和刷涂法将其应用于古建筑砂岩的保护研究。结果表明:P(BA-MMA-co-DFHM)溶液因分子量小而容易渗到砂岩内部,在降低砂岩吸水率,提高耐紫外光和耐冻融老化性方面,更能起到良好的保护效果。     

有机硅-丙烯酸酯聚合物乳液合成及粒径分析

通过种子乳液半连续法合成了有机硅改性丙烯酸酯聚合物乳液,并对其粒子形态及分布进行分析。结果表明:通过种子乳液半连续聚合工艺可制备出固含量42wt%,乳化剂含量4wt%(基于单体量)、窄分布纳米粒子的有机硅改性丙烯酸酯聚合物乳液。随反应进行,粒径分布变窄,平均粒径逐渐增大。随乳化剂中SDS与OP-10的摩尔比减少,粒径增大。     

统计结构含氟丙烯酸酯共聚物的合成与表征

本文对含氟丙烯酸酯(FMA)与甲基丙烯酸丁酯(BMA)的RAFT细乳液共聚合及动力学进行了研究, 计算得到了FMA与BMA的竞聚率并制备出具有统计结构的含氟共聚物乳液.     

细乳液聚合制备阳离子型含氟烷基丙烯酸酯共聚物乳液

采用细乳液聚合技术制备得到稳定的阳离子型甲基丙烯酸甲酯/甲基丙烯酸十八烷基酯/含氟烷基丙烯酸酯共聚物乳液,考察了均质强度(振幅)、均质时间以及难溶助剂十六烷(HD)用量对阳离子型FA共聚物乳胶粒尺寸及形貌的影响.结合TEM和纳米粒度及电位分析仪测试数据分析发现,均质条件的改变明显影响该阳离子型FA共聚物乳胶粒的粒径大小,粒径在80～150nm之间变化.细乳液聚合技术得到内部形态多样的乳胶粒,长链的含氟烷基链微相分离,更有助于提高该FA共聚物乳胶膜的憎水性,水滴在经阳离子型FA细乳液处理后的棉布上的平衡静态接触角最高可达150°.     

核壳型含氟丙烯酸酯共聚物的合成及性能

采用饥饿态半连续种子乳液聚合方法, 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, 分别选用甲基丙烯酸三氟乙酯(TFEM)、甲基丙烯酸六氟正丁酯(HFBM)和甲基丙烯酸十二氟庚酯(DFHM)为含氟单体, 合成以丙烯酸正丁酯(BA)、甲基丙烯酸甲酯(MMA)和含氟单体为原料的核壳型结构含氟丙烯酸酯共聚物乳液. FTIR, 1H NMR, TEM和DSC分析结果显示, 获得了BA/MMA/含氟单体的共聚物乳液, 且乳液具有明显的核壳结构. DSC, TGA和SEM-EDX的分析显示, 核壳型结构的共聚物具有优异的热力学稳定性能和成膜性能; 长侧链或短侧链含氟单体对共聚物的热稳定性影响不明显, 但侧链较长的含氟单体所获得的聚合物在成膜过程中更易向表面迁移, 更能体现含氟聚合物的优点.     

含氟共聚乳液改善浸渍滤纸抗水抗油性的研究

用核/壳乳液聚合工艺,通过改变单体组成、设计乳胶粒子的形态结构和在乳胶粒子的壳层中引入含氟丙烯酸酯单体,制备具有核/壳结构的含氟丙烯酸酯的共聚乳液。并通过FTIR1、3C-NMR、TEM等手段对共聚乳液的化学结构以及乳胶粒子形态结构进行了表征。同时研究了含氟单体种类和用量、乳化剂种类以及单体加料方式对其聚乳液性能以及浸渍滤纸抗水/油性的影响。     

Emulsifier-free latex of fluorinated acrylate copolymer

Emulsifier-free latices of fluorinated acrylate copolymers were prepared by semicontinuous polymerization method, with perfluoroalkylethyl methacrylate (Zonyl TM) as a fluoromonomer. Ultrasonic at 40 kHz was adopted to help monomers disperse well in water. The relationships of polymerization conditions between the final conversion and polymerization stability were discussed in detail and the optimal polymerization condition was given. A fluorinated acrylate copolymer was finally obtained and its T_g was 54 °C. The average particle size of the latex was about 601 nm and the particle size distribution of the latex was narrow. The latex film exhibited a low surface free energy and good surface property. By using 6% Zonyl TM, the water contact angle of the film-air interface increased significantly and reached to 110.2°. Compared with the latex film of fluorine-free polyacrylate prepared under the similar polymerization condition, the fluorinated latex film had a better water-resistance and thermal stability.     

含氟丙烯酸酯三元共聚物乳液的研究

以丙烯酸全氟烷基酯 (ZonylTM)、甲基丙烯酸甲酯 (MMA)、丙烯酸丁酯 (BA)为原料 ,在阴离子乳化体系中制备了含氟丙烯酸三元共聚物乳液 .研究了聚合反应动力学、转化率的各种影响因素 ,得出了聚合速率方程 ,并得出反应的表观活化能 (Ea)为 5 0 75 8kJ mol.考察了乳液的稀释稳定性、贮存稳定性、离心稳定性、耐热、耐寒稳定性 ,及乳胶膜的吸水性和耐溶剂性 .并用Wilhelmy方法测定了乳胶膜与水的接触角 ,结果表明乳胶膜对水的抗浸润力大大提高     

Preparation and characterization of emulsifier-free core–shell interpenetrating polymer network-fluorinated polyacrylate latex particles

The emulsifier-free core–shell interpenetrating polymer network (IPN) fluorinated polyacrylate latex particles with fluorine rich in shell were prepared by emulsifier-free seeded emulsion polymerization with water as the reaction medium. The fluorinated copolymer could be fixed on the particle surface due to the formation of interpenetrating polymer network. The resultant core–shell particles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS) analysis, Fourier transform infrared (FTIR) spectrometry, X-ray photoelectron spectroscopy (XPS) analysis and thermogravimetric analysis (TGA). The core–shell particles possessed very narrow monomodal particle size distributions. XPS analysis of the latex film displayed that perfluoroalkyl groups had the tendency to enrich at surface and there was a gradient concentration of fluorine in the structure of the latex film from the film–air interface to the film–glass interface. In addition, compared with the latex film of crosslinked polyacrylate prepared under the same condition, the emulsifier-free core–shell IPN-fluorinated polyacrylate latex film showed better thermal stability, higher contact angle and lower water uptake.     

Synthesis and characterization of emulsifier-free trilayer core–shell polysilsesquioxane/polyacrylate/poly(fluorinated acrylate) hybrid latex particles

The trilayer core–shell polysilsesquioxane/polyacrylate/poly(fluorinated acrylate) (PSQ/PA/PFA) hybrid latex particles are successfully prepared, using functional PSQ latex particles with reactive methacryloxypropyl groups synthesized by the hydrolysis and polycondensation of (3-methacryloxypropyl)trimethoxysilane in the presence of a reactive emulsifier as seeds. Transmission electron microscopy (TEM), scanning electron microscopy (SEM) and dynamic light scattering (DLS) confirm that the resultant hybrid latex particles have evident trilayer core–shell structure and a narrow size distribution. The Fourier transform infrared (FTIR) spectra show that fluorinated acrylate monomers are effectively involved in the emulsion copolymerization and formed the fluorine-containing hybrid latex particles. XPS analysis of the obtained hybrid latex film reveals that the intensity of fluorine signal in the film–air interface is higher than that in the film–glass interface. In addition, compared with pure polyacrylate latex film, the obtained fluorine-containing hybrid film shows higher hydrophobicity and thermal stability, and lower surface free energy.     

PREPARATION AND SURFACE PROPERTIES OF ACRYLIC COPOLYMERS CONTAINING FLUORINATED MONOMERS

A series of copolymers comprising butylmethacrylate, styrene, butylacrylate, hydroxypropyl acrylate and perfluoroalkyl methacrylate were synthesized by the free radical polymerization using BPO as an initiator. The surface property of the copolymer films was subsequently characterized. The contact angle measurements and energy dispersive analysis of X-ray （EDAX） show that the length and content of perfluoroalkyl side chains in the copolymers are crucial for the preparation of the film with low surface energy. At a given content of fluorinated monomers in the copolymers, the longer the perfluoroalkyl side chain, the larger the water contact angle of the copolymer films will be. On the other hand, the higher the content of fluorinated monomers, the lower the surface energy is. The water contact angle increases with the increase of the fluorinated monomer content and reaches a plateau at 3 wt% of fluorinated monomer content.     

Preparation and characterization of gradient distribution of silicon in emulsion blend films

In this work, a functional gradient polymeric material derived from silicon-containing acrylate blend emulsion film is prepared in two steps. Firstly, 3-[tris(trimethylsilyloxy)silyl] propyl methacrylate (TRIS)-modified acrylate latex is prepared using multiple emulsifiers by the two-stage semicontinuous emulsion copolymerization method. Next, blend latexes composed of TRIS-containing and TRIS-free acrylate latexes are obtained. Detailed studies on the effects of the film-formation temperature and the glass transition temperature (T _g) differences on the compositional gradient film are conducted. Surface energy analysis shows that silicon elements enriched at the film-air (F-A) interface and T _g differences facilitate the fabrication of silicon gradient in emulsion blend films. Scanning electron microscopy-energy dispersive X-ray further reveals that the concentration of silicon components varies in a gradient-like manner along the overall transaction of the film when the film-formation temperature is 55 °C. However, excessive temperature creates the formation of a segmental gradient distribution of silicon in the emulsion blend films.     

含氟丙烯酸酯聚合物乳胶膜表面性质

采用XPS和界面张力仪分别测定了含氟丙烯酸酯聚合物乳胶膜表面的组成及水在其表面的动态接触角, 并用状态逼近方程模型计算了含氟聚合物乳胶膜的表面张力, 考察了温度对乳胶膜润湿性的影响. 结果表明, 含氟聚合物乳胶膜表层较深处的F 1s信号强度比近表面要弱, 乳胶膜表面张力随表面氟原子浓度增加在一定程度上呈现线性下降；含氟侧链(Rf)较长(碳原子数n＞6)的含氟聚合物, 其表面张力随Rf单元含量增加而下降的趋势显著高于Rf较短(n≤6)的含氟聚合物, 而水在含氟聚合物乳胶膜表面上的后退接触角θr随n增大出现急剧上升, n≥10 时, θr值几乎恒定不再随n增大而改变. 此外, 参与共聚的非氟丙烯酸酯酯基碳链较短时, 水在共聚物乳胶膜表面的θr随氟单元含量增加而增加的趋势更显著；温度超过40 ℃后, 水对聚合物乳胶膜的润湿性随温度上升略有改善.     

Synthesis and characterization of core–shell polyacrylate latex containing fluorine/silicone in the shell and the self-stratification film

A series of core–shell polyacrylate latexes with different fluorine/silicone monomer concentrations were prepared successfully by seeded emulsion polymerization. Dodecafluoroheptyl methacrylate and perfluorooctyl methacrylate with different fluorinated side chains were employed as fluorinated monomers, and γ-methacryloxypropyl triisopropoxidesilane (MAPTIPS) was used as a silicone-containing monomer as well as a self-cross-linking agent. The morphology and chemical structure of the latexes were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, and differential scanning calorimetry, and the self-stratification properties of the latex film were verified by X-ray photoelectron spectroscopy and static contact angle measurement. The results showed that the fluorine/silicone-containing polyacrylate latexes presented a uniformly spherical core–shell structure, and the latex films displayed a preferential distribution of fluorinated composition near the surface, which was more remarkable with the synergism effect between the fluorine monomer and MAPTIPS. Additionally, the hydrophobicity and oleophobicity of the latex films exhibited high relevance with the fluorine/silicone monomer concentrations as well as the fluorinated side-chain structure.     

含氟丙烯酸酯共聚乳液及其膜表面特性的研究

以十二烷基硫酸钠 (SDS)和OP 10混合乳化剂 ,制备了甲基丙烯酸全氟辛基乙酯 (FMA8) 甲基丙烯酸丁酯 (BMA) 甲基丙烯酸 (MAA)共聚乳液 .通过DSC、FT IR、1 H NMR对共聚物的结构、组成进行了表征研究 .采用JZHY 180界面张力仪研究了共聚乳液膜表面的性质 ,结果表明 ,随着共聚物中全氟单体含量的增加 ,共聚物膜的表面能显著降低 ,当全氟单体的含量达到 2 5wt %时 ,其表面能降低到 19 74mJ m2 .X ray光电子能谱(XPS)对共聚物表面原子组成的分析结果表明 ,共聚物表面氟的含量远高于其平均含量 ,证明了含氟基团的趋表现象 .经退火处理 ,共聚物膜表面的氟含量增加 ,表面自由能降低