丙烯酸氟烷基酯乳液聚合的研究

以甲基丙烯酸氟烷基酯(ZonylTM)、甲基丙烯酸甲酯、丙烯酸正丁酯为原料,采用氧化-还原引发体系,以十二烷基硫酸钠和全氟辛酸铵(1:1)为乳化剂,经超声波预乳化后进行聚合,成功制备了一系列高氟单体含量的三元共聚物乳液,系统研究了聚合条件对乳液稳定性和反应动力学的影响,测得聚合反应的表观活化能Ea为68.4kJ/mol。考察了氟元素含量对共聚物表面性能的影响,含氟共聚物对水和对油的接触角最高可分别为116°和77.5°。     

含氟丙烯酸酯共聚物乳液的制备及性能研究

以丙烯酸全氟辛基乙酯为主要单体,采用乳液聚合法制备了含氟丙烯酸酯共聚物,通过红外光谱和激光粒度分析对共聚物进行了表征,测试了共聚物乳液的稳定性,研究了单体含量和交联剂对共聚物性能的影响,测定了共聚物于皮革表面的防水、防油性能,并对共聚物乳液处理的皮革表面进行了SEM分析。结果表明,含氟丙烯酸酯共聚物乳液防水等级9级,防油等级6级,具有良好的低表面性能。     

含氟丙烯酸酯乳液高疏水性与低氟含量的平衡探索

为了研究含氟丙烯酸酯乳液涂膜的疏水性与氟含量的平衡关系,以甲基丙烯酸十二氟庚酯(DFHM)为含氟单体,双丙酮丙烯酰胺(DAAM)和己二酸二酰肼(ADH)为交联单体,采用半连续核壳乳液聚合的方法合成了一系列自交联含氟丙烯酸酯共聚物乳液。研究表明:含氟单体含量为12%(即氟含量为6.84%,均以聚合单体的总质量计,下同)时,含氟基团在涂膜表面可以达到饱和,乳液固含量可达38.2%;再添加4%交联单体,涂膜的水接触角为116.6°。当含氟单体含量降为4%(氟含量2.28%)时,通过提高成膜温度或添加成膜助剂,也可使涂膜表面的水接触角达到104.2°,具有较好的疏水性能。     

含氟丙烯酸酯改性聚氨酯核壳乳液的制备及表征

以双键封端水性聚氨酯为反应型高分子,全氟丁基磺酸钾为含氟乳化剂,实现甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、甲基丙烯酸十二氟庚酯(G04)和聚氨酯的共聚,制备具有核壳结构的含氟丙烯酸酯改性聚氨酯乳液(FPUA)。傅里叶变换红外光谱(FTIR)和透射电子显微镜(TEM)对共聚物组成、乳胶粒的形态进行表征,并通过表面接触角、拉伸实验和热重分析等分别研究了FPUA胶膜的表面能、力学性能和热性能。结果表明,当含氟乳化剂和氟单体用量分别为单体总质量的0.15%和20%时,乳液稳定性好,聚合物胶膜表面能由45.6mN/m下降至22.5 mN/m,表现出良好的疏水疏油性,最大热失重速率温度由348℃提高至398℃。     

含氟水性聚氨酯-丙烯酸酯涂料的制备及其成膜强度和耐水性的研究

采用原位乳液聚合法,合成了含氟自交联型水性聚氨酯-丙烯酸酯(FPUA)乳液.研究了单体物质的量比、环氧基团含量和氟单体含量对乳液制备过程、乳液及涂膜性能的影响.通过红外光谱、热重分析对其结构和膜性能进行表征,并对涂膜表面的水接触角进行了研究.结果表明:n(—NCO)∶n(—OH)=1.4、n(—NHNH2)∶n(—CO—)=1、GMA用量为4％、含氟单体用量为6％时,合成乳液稳定性良好,涂膜的耐水性和热稳定性良好.在成膜时复合乳液中的氟基团向空气/聚合物界面伸展,有效地覆盖涂膜表面,降低涂膜表面能,水在涂膜上的接触角达到117.2°.     

含氟乳化剂丙烯酸酯乳液的制备及性能

以丙烯酸丁酯、甲基丙烯酸甲酯、丙烯酸、十二烷基硫酸钠为主要成份分别制备了含氟乳化剂FC80、FC91 1、FC90 8、4 FC氟醇的丙烯酸酯共聚物乳液 ,测定了它们的表面张力、粘度、PH值、固含量等性能 ,重点讨论了 FC80含量对乳液性能的影响。实验发现在 FC80含量为 0 .0 5%时丙烯酸酯共聚物乳液性能变化明显     

含全氟己基基团的甲基丙烯酸酯共聚物的合成及性能对比

分别将几种含氟单体(FA)与甲基丙烯酸丁酯(BMA)、丙烯酸乙酯(EA)聚合得到三元共聚物,通过IR、DSC、GPC、TGA等测试手段分别对其涂膜性能进行了研究对比。结果表明,全氟己基侧链的引入能有效提高涂膜的拒水能力和耐高温性能;芳香环的引入提高了涂膜的硬度及耐高温性能。利用热场发射扫描电镜(OXFORD EDX)对聚合物薄膜截面的氟元素分布进行了分析,显示退火工艺有助于含氟基团更好的向涂膜表面迁移,氟元素沿膜截面呈梯度分布。     

环氧乳液与含氟乳液的拼混研究

运用种子乳液聚合法制备了固含量(固体质量分数)为45%的含氟乳液;运用后乳化法制得了环氧乳液。ATR-FTIR测试表明环氧乳液与含氟乳液进行了有效的拼混。运用KrussK12型动态表面能分析仪测试了含氟涂膜对水和十六烷的接触角,对影响拼混乳液涂膜性能的因素如环氧树脂及其固化剂的比例、氟原子含量、成膜基材材质、成膜温度等进行了探讨研究。结果表明制备的含氟拼混乳液性能良好。     

含氟聚合物系列产品的性能及应用

概述了四氟乙烯/六氟丙烯共聚物及其化学改性系列产品、聚四氟乙烯化学改性系列产品、偏氟乙烯/六氟丙烯共聚物及其化学改性系列产品、偏氟乙烯/六氟丙烯/四氟乙烯三元共聚物、含氟涂料用树脂等含氟聚合物系列产品的性能及应用。     

水性含氟丙烯酸涂料的制备及性能研究

采用自制的端烯丙基丙烯酸丁酯-含氟丙烯酸酯嵌段共聚物(DMPA)与丙烯酸的乳液共聚,制备了一种水性含氟丙烯酸乳液。采用核磁分析、红外光谱、接触角等测试方法对水性含氟丙烯酸乳液涂层的性能进行了分析。结果表明,端烯丙基丙烯酸丁酯-含氟丙烯酸酯嵌段共聚物添加量为30%时,水性含氟丙烯酸乳液的疏水效果最好,且水性含氟丙烯酸乳液制备的涂料具有最佳的综合性能。     

Synthesis of Bis(1H, 1H, 2H, 2H‐perfluoro‐octyl)methylenesuccinate copolymers and their application on cotton fabrics

Bis(1H, 1H, 2H, 2H‐perfluoro‐octyl)methylenesuccinate (FOM)/ethyl acrylate (EA)/methyl methacrylate (MMA) copolymer (FOME) latexes, FOM/butyl acrylate (BA)/MMA copolymer (FOMB) latexes, and FOM/octyl acrylate (OA)/MMA copolymer (FOMO) latexes were synthesized by continuous emulsion polymerization. Solution polymerization was also carried out to prepare FOMB. The influences of fluorine content and curing conditions on the surface properties of polymer films were discussed. The water and oil repellency of cotton fabrics treated with the FOM copolymers was better than that of conventional poly(fluoroalkyl acrylate)s containing the same fluorinated chain. The polymer films or the treated fabrics were characterized by Fourier transform infrared, scanning electron microscope, atomic force microscopy, thermogravimetric analysis, x‐ray photoelectron spectrometry, and wide angle x‐ray diffraction. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci, 2013     

Fluorinated poly(meth)acrylate: Synthesis and properties

Due to good reactivity of fluorinated (meth)acrylates with other monomers or polymer segments, fluorinated poly(meth)acrylates possess more economical and convenient synthesis routes than other fluoropolymers. This feature article initially summarizes different types of fluorinated (meth)acrylates, which can be divided into fluorinated alkyl (meth)acrylates and fluorinated aryl (meth)acrylates. Subsequently, various approaches for synthesizing fluorinated poly(meth)acrylates including random, block, graft or star copolymers are described. Conventional free radical polymerization can be used in synthesizing random copolymers, while controlled/“living” radical polymerization can provide well-defined copolymers with accurate control over molecular weight and special structures as expected. In particular, introduction of fluorinated components into as-prepared copolymers offers an alternative route to synthesize fluorinated poly(meth)acrylates which are difficult to be obtained directly via polymerization. The incorporation of fluorine can confer unique and highly desirable properties to poly(meth)acrylates such as low surface energy, thermal stability, chemical and weather resistance, low refractive index, and self-organization characteristics. Such properties are described in great details based on many recent articles.     

Synthesis and Characterization of Water-Borne Adhesives Based on 2-Ethylhexylacrylate-butylacrylate Copolymers Functionalized with Acrylic Acid

ABSTRACT

A series of copolymers, based on 2-ethylhexylacrylate (2-EHA) and butylacrylate (BuA), and functionalized with small amounts of acrylic acid (AA) were synthesized by emulsion polymerization techniques and monodisperse latexes were obtained. Their average particle size and particle size distribution were determined by quasi-elastic light scattering and confirmed by transmission electron microscopy. The change in the adhesive properties (peel, shear, and tack) as a function of 2-EHA/BuA ratio was studied. An optimal balance between these three properties was determined at a 2-EHA/BuA ratio 10/90 wt/wt. The influence of the functionalization of these copolymers with AA was also evaluated when the comonomers ratio was kept constant. Good results were found at an AA content of 1 wt%.     

Preparation and surface properties of fluorine-containing diblock copolymers

Two series of semifluorinated fluorocarbon diblock copolymer poly(butyl methacrylate-co-perfluoroalkyl acrylate) have been synthesized by atom transfer radical polymerization (ATRP). The ¹H NMR, F-EA, GPC and FTIR were used to characterize copolymer structure. Contact angle measurements on the thin polymer films showed low critical surface tensions and low dispersion force contributions to the surface energy, which indicated the presence of the fluorinated block at the surface. The results showed that the water- and oil-repellency increased with the fluorine content in the diblock copolymers. After annealing at different temperatures or different times, the water- and oil-repellent properties of diblock copolymer were increased to approach maximum values. This phenomenon proves the propensity of polymer for fluorine enrichment at air-polymer surface.     

Surfactant-free artificial latexes from modified styrene-maleic anhydride (SMA) copolymers

We describe the preparation of surfactant-free artificial latexes on the basis of poly(styrene-alt-maleic anhydride) (SMA) copolymers. The SMA copolymers were first partially alkyl-imidized and then partially ammonolyzed in acetone. Upon adding to water and after the removal of acetone, the modified copolymers formed stable latexes, with a diameter of ∼150 nm and a PDI < 0.2. In the absence of alkyl groups the particles became completely soluble in water after a few days. The latexes from the partially alkyl-imidized polymer were found to remain stable at pH > 2. The incorporation of alkyl groups into the copolymers significantly lowered the T_g of the polymer from 150 to 75 °C, depending on the amount of alkylamines added. It was found that the molecular weight as well as the molar mass distribution of the SMA polymers did not show major effects on the properties of the artificial latexes.     

The application research of environment-friendly reactive surfactants in acrylate emulsion pressure sensitive adhesives

In this article acrylate pressure sensitive adhesive (PSA) latexes were synthesized via a pre-emulsion seeded semi-batch emulsion polymerization process with a conventional nonreactive surfactant (CO-436) and two polymerizable surfactants (traditional surfmer SE-10N and environment-friendly surfmer SR-10). The effects of surfactant contents on the particle size, zeta potential, electrolyte stability of the latexes and gel content, sol molecular weight (M_w, M_n), water absorption of the PSA copolymers were investigated. In addition, X-ray photoelectron spectroscopy (XPS) and contact angle measurements were used to characterize the latex films. The results showed that the particle sizes of latexes prepared with surfmers were smaller than their CO-436 containing counterparts. And the latexes prepared with surfmers had a lower storage stability than the one prepared with CO-436. However, surfmers can improve the electrolyte stability of the latex. Furthermore, the water resistances of the latexes prepared with surfmers were better than that of the latex with CO-436, which can be confirmed by water absorption, contact angle and XPS analysis. The results also indicated that the PSA prepared with SR-10 exhibited the highest gel content among the three surfactants. Finally, the effects of surfactants on the adhesive properties of the PSAs were also evaluated.     

含氟丙烯酸酯共聚乳液合成及性能研究

以甲基丙烯酸甲酯（MMA）、丙烯酸丁酯（BA）和全氟烷基丙烯酸酯等为主要原料,丙二醇为分子量调节剂,采用非离子阴离子复合乳化剂、氧化还原引发体系、超声微乳化技术,不同的加料方式制备出系列含氟丙烯酸酯乳液,并利用衰减全反射红外光谱（ATR-FTIR）对含氟丙烯酸酯共聚乳液胶膜进行了表征。采用接触角测定方法研究了含氟共聚乳液对织物整理后的表面性能变化,结果显示：乳液整理后的纯棉无纺布的拒水拒醇性大大提高,对水的接触角达到127o左右,对醇的最大接触角达到112o。乳液整理后的PP无纺布拒醇性明显改善,接触角达到101o左右。但拒水性能未见明显提高。     

CTFE与VAc共聚物的制备

在超临界CO2中制备三氟氯乙烯(CTFE)与乙酸乙烯酯(VAc)共聚物P(CTFE-co-VAc),考察了单体配比对聚合反应、产物结构及性能的影响,研究了共聚物的表面性能及其溶液黏度。控制单体配比可得到不同结构、不同氟含量的共聚物。当m(VAc)/m(CTFE)小于4∶16时,产物中y(CTFE)恒定在50%左右;氟含量是影响共聚物表面性能的关键因素,共聚物中CTFE单元的比例增加,则产物中氟含量增大,产物对溶剂的接触角变大,当产物中w(F)为29.16%时,聚合物膜的表面能最小,为0.028 J/m2;聚合物溶液黏度随共聚物中VAc结构单元比例增加而增大。     

松香改性丙烯酸酯乳液的合成及其在PVC地板胶的应用

采用半连续种子乳液聚合的方法制备了一种具有核壳结构的松香树脂改性PVC地板胶用丙烯酸酯聚合物乳液,讨论了松香树脂质量分数、松香树脂加入方式、核壳质量比等因素对聚合物乳液性能的影响。结果表明,当松香树脂质量分数为2%,核壳单体的质量比为1∶2时,乳液的初黏性(#33)达到1.3 cm,粘接强度达到0.32 MPa。     

Structure-property-performance relationships of sulfonated poly(arylene ether sulfone)s as a polymer electrolyte for fuel cell applications

This article focuses on structure-property-performance relationships of directly copolymerized sulfonated polysulfone polymer electrolyte membranes. The chemical structure of the bisphenol-based disulfonated polysulfones was systematically alternated by introducing fluorine moieties or other polar functional groups such as benzonitrile or phenyl phosphine oxide in the copolymer backbone. Ac impedance measurements of the polymer electrolyte membranes indicated that fluorine incorporation increased proton conductivity, while polar functional group incorporation decreased conductivity. Likewise, other properties such as water uptake and ion exchange capacity are impacted by the incorporation of fluorine moiety or polar groups. These properties are critically tied with H₂/air and direct methanol fuel cell performance. We have rationalized fuel cell performance of these selected copolymers in light of structure-property relationships, which gives useful insight for the development and application of next generation polymer electrolytes.