Preparation and properties of alkoxysilane/butyl acrylate/methyl methacrylate copolymer latices

The incorporation of alkoxysilanes into latex systems is of major interest in the field of colloidal science. Two kinds of vinyl‐containing alkoxysilanes, methacyloxypropyltrimethoxyl silane and vinyltriethoxysilane, were copolymerized with butyl acrylate and methyl methacrylate by seeded emulsion polymerization, and copolymer latices were obtained. The morphologies of the latex particles were characterized with transmission electron microscopy. Dynamic light scattering showed that the particle size increased and the particle size distributions of all the copolymer latex particles were alike with increasing amounts of organosilane. The effects of the organosilane content on the morphology of the particles, the rheology, and the swelling properties were also investigated. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

苯乙烯/丙烯酸丁酯微乳液共聚物链段分布的研究

以苯乙烯/丙烯酸丁酯(St/BA)为共聚单体,进行了微乳液聚合反应,测定了共聚物组成和共聚单体的竞聚率。由竞聚率计算了共聚物分子的链段分布,分析了共聚物分子的微观结构。     

苯乙烯/丙烯酸丁酯微乳液聚合竞聚率及共聚物链段分布的研究

以苯乙烯/丙烯酸丁酯(St/BA)为共聚单体进行了微乳液聚合反应,测定了共聚物组成和共聚单体的竞聚率。由竞聚率计算了共聚物分子的链段分布,分析了共聚物分子的微观结构。     

影响丙烯酸酯类共聚物性能的因素

综述了乳化剂用量、核、中间层、壳、粒子粒径及粒径分布等对具有核壳结构的丙烯酸酯类共聚物性能的影响。选择适量的乳化剂和交联剂，合适的反应工艺，控制丙烯酸酯类共聚物粒径及粒径分布，是得到具有良好性能丙烯酸酯类共聚物的必要条件。     

高固含量苯丙微乳液的合成与表征

以过硫酸铵(APS)为引发剂,反应性乳化剂烷基酰胺乙烯磺酸钠(DNS-86)和辛基酚聚氧乙烯醚(OP-10)为复配型乳化剂,正戊醇(n-PTL)为助乳化剂,采用种子乳液聚合法制备苯乙烯(St)、丙烯酸甲酯(MA)、丙烯酸丁酯(BA)、丙烯酸(AA)的四元共聚微乳液。讨论了引发剂用量、乳化剂用量及配比、软硬单体配比等因素的影响。FT-IR和DSC测试结果表明,苯乙烯、丙烯酸酯类单体间发生了自由基共聚反应;TEM测得乳胶粒子平均粒径为35 nm。当m(BA)∶m(St MA)=4∶6,m(DNS-86)∶m(OP-10)∶m(n-PTL)=11∶3∶2,引发剂用量为单体质量的0.7%时,所得乳液性能优良,粒径在纳米范围内。     

壳聚糖/N-乙烯基吡咯烷酮接枝共聚物的制备及其性能

以壳聚糖（CS）和N-乙烯基吡咯烷酮（NVP）为原料,本文采用过氧化氢和抗坏血酸共引发剂引发,制备壳聚糖/N-乙烯基吡咯烷酮的接枝共聚物（CS-g-NVP）,研究了引发剂配比、反应温度和反应时间等因素对接枝共聚反应的影响。通过红外光谱、核磁共振和热重分析等对产物进行表征,并考察其吸湿性和亲水性能。结果表明,接枝共聚反应的最佳条件为：引发剂抗坏血酸/过氧化氢的摩尔比为1∶1、反应温度60℃、反应时间12h。接枝共聚产物的吸湿性优于壳聚糖,在饱和氯化钙和饱和硫酸铵环境下产物的吸湿率分别为3.68%和23.1%,高于原料壳聚糖的0.41%和9.77%,产物具有良好的亲水性和水溶性,能溶解于酸性和碱性水溶液中。     

Preparation and properties of cycloolefin copolymer/silica hybrids

Polymer substrates are widely used in the flat‐panel‐display industry because of their flexibility, light weight, and high power efficiency. However, the lower glass‐transition temperatures and thermal stability and higher water/oxygen permeation of cycloolefin copolymers (COCs) constrain their applications in display substrates. In this research, COC/tetraethyloxysilane (TEOS) hybrids were synthesized via a sol–gel process. Differential scanning calorimetry indicated that the glass‐transition temperature of the hybrids was higher than that of neat COC and rose significantly as the TEOS content was increased from 1 to 15 wt %. According to an analysis of IR spectra, the fraction of hydrogen‐bonded carbonyl groups in the hybrids increased as the TEOS content increased. This meant that the interfacial interaction contributed by hydrogen bonds for the COC/TEOS hybrid system increased as the TEOS content increased from 1 to 15 wt %. On the basis of scanning electron microscopy, the number of dispersed droplets of silica increased as the content of TEOS increased. The decomposition temperatures of the hybrids, investigated with thermogravimetric analysis, were not affected significantly by the addition of TEOS. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2542–2548, 2007     

Preparation and properties of UV-cured epoxy acrylate/glycidyl-POSS coatings

Epoxy acrylate (EA)/glycidyl-polyhedral oligomeric silsesquioxane (G-POSS) nanocomposites were synthesized via in situ ultraviolet initiated polymerization. XRD analysis indicates that G-POSS and EA are miscible and can form uniform composites. SEM micrographs show that the G-POSS particles (<500 nm in diameter) disperse uniformly in the polymer matrix. The EA/G-POSS nanocomposites exhibit heterogeneous morphology. FTIR analysis confirms the curing reaction is quite complete, and there are no chemical reactions between G-POSS and EA during the UV-curing process. The carbon–carbon double-bond conversion vs time profiles confirm that the addition of G-POSS improves the UV-curing rates of nanocomposites. The glass transition temperature (T _g) of nanocomposites were obtained by DMA. T _g reaches to the maximum at the loading of 1 wt% and then decreases with the increasing G-POSS loadings. The thermal stability, impact resistance, and flexibility of nanocomposites are all enhanced by the incorporation of G-POSS.     

柴油微乳液的制备及性能研究

采用油水法并结合超声分散法,在30℃下以油酸为表面活性剂、二乙基二乙醇胺为主剂,以甲醇和乙醇作为助剂,采用甲醚和乙醚作为溶剂,制备出最大增溶水量为26.16%的柴油微乳液,对柴油微乳液进行了运动粘度、稳定性、腐蚀性、密度、静置燃烧等理化性能的检测。结果表明,制备出的柴油微乳液具有较低的运动粘度,比0#柴油具有更优异的耐低温性能;室温稳定时间为205~424 d;各样品的腐蚀度均为1A级,不会对内燃机造成腐蚀。该柴油微乳液成本较低,具有广泛的应用前景。     

耐沾污聚氨酯-苯丙-含氟丙烯酸酯共聚乳液的制备

以含氟PU(聚氨酯)为壳、低Tg(玻璃化转变温度)的苯丙(SA)共聚物为核,采用乳液聚合法成功制备出FPUA(PU-SA-含氟丙烯酸酯三元共聚物)乳液;然后以此为基体,制备了水性外墙弹性涂料。采用透射电镜(TEM)、动态光散射(DLS)法、红外光谱(FT-IR)法和差示扫描量热(DSC)法等分别测定了FPUA乳液的微观形貌、粒径及其分布、结构、Tg和水接触角。研究结果表明:FPUA乳胶粒呈规则球形状核/壳结构,FPUA乳胶膜的水接触角高达100.1°,由其制成的水性外墙弹性涂料解决了低Tg乳胶膜的"热黏冷脆"等问题。     

Phase behavior of a sodium dodecanol allyl sulfosuccinic diester/n‐pentanol/methyl acrylate/butyl acrylate/water microemulsion system and preparation of acrylate latexes by microemulsion polymerization

Pseudoternary phase diagrams of quaternary microemulsion systems composed of the reactive surfactant sodium dodecanol allyl sulfosuccinic diester, n‐pentanol, methyl acrylate/butyl acrylate, and water were made. The influence of the mass ratio of sodium dodecanol allyl sulfosuccinic diester to the cosurfactant (n‐pentanol) in the system and the influence of electrolyte sodium chloride on the microemulsion area were examined. The microstructure of the microemulsion was determined with a conductance technique. The results suggested that there were three structures in the microemulsion system: water in oil, oil in water, and a bicontinuous phase. Microemulsion polymerizations were carried with some point in the microemulsion region being chosen as the formulation. The structure and configuration of the polymer latexes were determined and analyzed with Fourier transform infrared, differential scanning calorimetry, and scanning electron microscopy. The results suggested that the reactive surfactant could participate in the polymerization with the monomers to some extent; the glass‐transition temperature of the latex was ?31.4°C. The polymer latex was transformed gradually from an open porous structure to a closed porous structure when its pregnant microemulsion was varied from a bicontinuous structure to an oil‐in‐water structure. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

含羧基团聚丙烯酸硅氧烷的制备及性能

1 引言 为了防止各种基材表面受到损伤或污染,已开发了可剥离的保护膜产品(以下简称保护膜).但是,一般市售的可剥离保护膜都比较厚,而且其应用仅限于简单的二元平面,对于含有三元曲面的构件则难以使用.虽然丙烯酸系或松香树脂类胶膜能够用碱性化学试剂脱膜,但是丙烯酸类胶膜经户外曝露后,用碱性化学试剂很难使被保护表面恢复原状.     

新型含硅氧烷丙烯酸酯共聚物的制备及其涂膜性能

以单体甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、硅烷偶联剂3-甲基丙烯酰氧丙基三甲氧基硅烷(KH570)为原料,采用自由基溶液聚合方法合成了一种含有机硅氧烷的丙烯酸酯共聚物P(MMA-BA-KH570),并将此共聚物与无机硅溶胶进行复配制得一种新型有机-无机杂化涂料.讨论了共聚物合成工艺的主要影响因素,利用傅里叶变...     

防水涂料用弹性丙烯酸酯共聚乳液的研制

介绍了防水涂料用高弹性丙烯酸酯共聚乳液的制备。该共聚乳液具有极好的耐候、耐酸雨、耐碱、耐低温和良好的矛韧性和附着强度。     

Preparation and properties of dual-cure polyurethane acrylate

Dual-cure polyurethane acrylates (PUA) with different double bonds content were synthesized by using aliphatic polyisocyanate and 2-hydroxyethyl acrylate (HEA). The molecular structures were identified by Fourier transform infrared (FTIR) spectrum and nuclear magnetic resonance (NMR). Molecular weight (M_w) and glass-transition temperature (T_g) of PUA were measured by gel permeation chromatography and DSC, respectively. The pendulum hardness, pencil hardness, flexibility and abrasion resistance properties of dual-cure system were tested, the results indicated that the pendulum hardness, pencil hardness, and MEK resistance increased, but the flexibility reduced with the double bonds content increased. The mechanical properties of dual-cure system were greatly improved after the heat treatment.     

含氟丙烯酸酯共聚物的合成及其涂膜表面疏水、疏油性能研究

以单体甲基丙烯酸甲酯、丙烯酸丁酯、丙烯酸、含氟(甲基)丙烯酸酯为原料,通过改变氟碳链长度、氟单体含量以及添加方式等因素,合成了一系列的含氟丙烯酸酯共聚物。利用表面接触角测试仪、红外光谱仪和多功能光电子能谱仪表征了共聚物涂膜的表面疏水、疏油性能以及表面化学成分,探讨了其影响因素。结果表明,共聚物涂膜表面疏水、疏油性能与其表面化学成分密切相关;使用长氟碳链的氟单体、增加氟单体用量以及采用在反应后期一次性加入氟单体的方法均有利于提高涂膜表面的疏水、疏油性能;当全氟辛基乙基甲基丙烯酸酯的质量分数为25%时,所得涂膜表面的氟元素质量分数达到44.284%,对水、对正十六烷的接触角分别达到127°和65°。     

聚氨酯丙烯酸酯/环氧丙烯酸酯分散体系的制备

用水性聚氨酯丙烯酸酯改性环氧丙烯酸酯,制备了聚氨酯丙烯酸酯/环氧丙烯酸酯分散体系。随着分散体中聚氨酯丙烯酸酯浓度的增加,体系稳定性增加,当其浓度达到30%时,可制得稳定的分散体系。这种分散体系可作为一种紫外光固化水性涂料,其涂膜的耐磨性、柔韧性都比环氧丙烯酸酯涂膜增强,而硬度变化不大。     

高固体质量分数丙烯酰胺共聚物反相微乳胶的制备

考察了相关因素对丙烯酰胺(AM)/2-丙烯酰胺基-2-甲基丙磺酸(AMPS)反相微乳液聚合反应的影响。实验发现,所得丙烯酰胺共聚物P(AM-co-AMPS)的相对平均分子质量随单体质量分数的增加而增大,随反应温度的升高、乳化剂质量分数的增加而减小;随引发剂的质量分数、pH值的增大呈现出先增大后减小的变化趋势;在相同实验条件下,以混合单体中m(AM)∶m(AMPS)=5时得到的P(AM-co-AMPS)相对平均分子质量最大。在反应温度为35℃,引发剂质量分数为单体质量0.23%的条件下,通过反相微乳液聚合反应,制得了质量分数w[P(AM-co-AMPS)]=31.0%透明、稳定的P(AM-co-AMPS)反相微乳胶。     

苯乙烯-乙烯/丁烯-苯乙烯三嵌段共聚物用填充油的制备及性能

采用增塑剂N 4006与不同黏度的石蜡基基础油进行调配,并加入不同种类及用量的光、热稳定剂,制备了2种苯乙烯-乙烯/丁烯-苯乙烯三嵌段共聚物(SEBS)用填充油(填充油A和填充油B),并对其光安定性及热安定性进行了研究。结果表明,紫外吸收剂G-1与酚胺类复合热稳定剂R-2有显著协同作用,可有效改善油品的光、热安定性。SEBS填充油B在加入光稳定剂G-1和热稳定剂R-2后,可达到较高的光、热安定性,光热稳定剂的最佳质量分数均为0.03%。     

Preparation and properties of urethane/acrylate composite by emulsion polymerization technique

Aqueous polyurethane–acrylic hybrid emulsions were prepared by semibatch emulsion polymerization of a mixture of acrylic monomers (styrene, butyl acrylate and acrylic acid) in the presence of polyurethane dispersion. Equivalent physical blends were prepared by mixing acrylic emulsion and polyurethane dispersion. The weight ratio between acrylic and polyurethane components was varied to obtain enhanced performance properties and microphase structure of hybrid latexes. The synthesized emulsion hybrids and physical blends were characterized by fourier transform infrared spectroscopy, thermogravimetric analysis. The experimental results indicate better acrylic–polyurethane compatibility in hybrid emulsions than in physical blends, resulting in improved chemical and mechanical properties. The blend ratio 50:50% (w/w) exhibited synergistic effects between the two polymers and revealed remarkable improvement in various coating properties over other blend ratios and the individual resin components.