水性双组分氟丙烯酸—聚氨酯涂料的研制及性能测试

介绍了水性双组分氟丙烯酸-聚氨酯涂料所用原料及其预处理,水性双组分氟丙烯酸-聚氨酯涂料的羟基组分采用两步法合成:第一步合成了具有大分子表面活性剂性能的水性聚氨酯,在合成的过程中引入了双键和羟基组分;然后采用无皂乳液聚合的方法合成了以氟丙烯酸酯为核、聚氨酯为壳的水性树脂。并列举了采用该树脂与水性固化剂配合研制的清漆的性能指标,该清漆有着非常广泛的用途,讨论了影响涂料性能的各种因素。该双组分清漆水性含氟丙烯酸酯-聚氨酯清漆具有优异的综合性能。     

氟、硅改性聚氨酯材料的研究进展

聚氨酯(PU)是一类用途广泛的工程材料,但用传统原料和方法制备的聚氨酯也存在诸多缺点,如耐热性、耐侯型不好,从而限制了它在工程技术领域的进一步应用。为此,聚氨酯的化学改性成为该领域的研究热点之一。作者综述了近年来氟、硅化学改性聚氨酯方面的研究进展,并对今后的研究发展进行展望。     

乳化体系对氟硅改性丙烯酸酯乳液性能的影响

采用不同的乳化体系来制备氟硅改性丙烯酸酯乳液,主要探讨了乳化体系对预乳化液稳定性、聚合稳定性、储存稳定性、转化率、粒径大小与分布以及吸水率的影响。结果表明,在所采用的乳化体系中,由聚氧乙烯-4-酚基醚硫酸铵盐(CO436)与1-丙烯基-α-羟基烷基磺酸钠(COPS-1)组成的复合乳液体系,可制得转化率高达98.85%的稳定乳液,乳液粒径呈单分散分布,乳胶膜的吸水率只有4.31%。     

改性h-BN/聚氨酯丙烯酸酯涂料的制备与性能

利用水热法制备羟基化六方氮化硼（BNNSs）,采用异佛尔酮二异氰酸酯（IPDI）和丙烯酸羟乙酯（HEA）在其表面进行接枝得到功能化六方氮化硼（Fh-BN）。然后将得到的Fh-BN掺入有机硅改性的聚氨酯丙烯酸酯（PUA）涂料中,成功制备出改性h-BN/聚氨酯丙烯酸酯涂料。研究了水热时间、温度对BNNSs硼羟基含量的影响,利用XPS分析得出水热反应最佳反应条件为180℃、12h,B—OH质量分数达到5.97%。通过机械性能、综合热分析、耐水性、涂层交流阻抗和Tafel极化曲线进行测试分析,掺杂0.75%Fh-BN涂膜硬度达到3H,耐冲击性50cm,柔韧性0.5mm;与未掺杂前涂层相比,吸水率降低4.96%;涂层耐热性提高,T_50%提升了6℃;耐水测试浸泡168h后涂膜无变化;电化学测试表明：0.75%Fh-BN涂层阻抗R₁达到1.818×10⁹Ω·cm²,比原有涂层提升了两个数量级,E_corr由-0.4886V正移至-0.32124V,I_corr由2.5552×10^-7A/cm²降低至1.5555×10^-8A/cm²。Fh-BN的引入显著提升了涂层的机械性能、热稳定性和耐腐蚀性。     

内交联单体对水性双组份涂料性能的影响

以三羟甲基丙烷三丙烯酸酯(TMPTA)为内交联单体,采用种子乳液聚合与交联单体分段滴加工艺合成羟基聚丙烯酸酯乳液（HPAE）,配制水性双组份聚氨酯涂料(WB 2K-PUR)。考查了TMPTA的添加量及其在核、壳中的分布对乳液聚合稳定性和涂膜性能的影响。研究表明：当TMPTA添加量为2 wt% 时,乳液聚合稳定性好,凝胶率仅为0.26wt%;涂膜的综合性能好,包括涂膜具有0.78硬度、96.4%交联度和92%光泽度。热重分析（TGA）表明：TMPTA在核壳中以3:7的比例分布的HPA涂膜具有较好的热稳定性。     

Scratch behavior of nano-alumina/polyurethane coatings

Incorporating metal-oxide nanoparticles such as nano-alumina and nano-silica into polymer coatings to enhance mechanical durability is widely utilized in the current antiscratch and mar technologies. In this article, a quantitative study of the effect of a nano-alumina additive on the surface mechanical properties and scratch behavior of a two-part polyurethane coating is reported. An instrumented indenter with a conical diamond tip is used to measure surface mechanical properties (modulus and hardness) and to perform scratch tests, over a wide range of scratch loads. The scratch behavior in terms of the onset of elastic–plastic transition and scratch morphology were characterized by laser scanning confocal microscopy. The scratch results were correlated to the surface mechanical properties and relevant bulk material properties to understand the overall scratch behavior of the coatings. The results show that the scratch behavior of the coatings depends strongly on the concentration of nano-alumina.

Thermal stability and dynamic mechanical behavior of acrylic resin and acrylic melamine coatings

Acrylic polyols of different hydroxyl numbers consisting of hydroxy ethyl methacrylate, methyl methacrylate, butyl acrylate, and styrene were prepared by free‐radical solution as well as suspension polymerization techniques in the presence of benzoyl peroxide initiator. These polyols were crosslinked with butoxy methyl melamine at a ratio of 85 : 15 in the presence of acid catalyst. The thermal stability of polyols and their corresponding crosslinked films was studied by thermogravimetric (TG) technique. The Broido and Coats–Redfern methods were used to calculate the activation energy of thermal decomposition from standard TG curves. Dynamic mechanical thermal analysis was used to study the dynamic mechanical properties and determination of glass‐transition temperature of acrylic/melamine crosslinked films. The results indicate that the thermal stability of polyols and crosslinked films strongly depends on the hydroxyl number of the acrylic polyols. It was found that acrylic polyols synthesized by suspension polymerization methods upon crosslinking yield more thermally stable and flexible films than polyols prepared by solution polymerization methods. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 27–34, 2004     

Application of a silicone-modified acrylic emulsion in two-component waterborne polyurethane coatings

Two-component waterborne polyurethane (2K WBPU) coatings were prepared using a silicone-modified acrylic emulsion as the hydroxyl component, and hydrophilically-modified polyisocyanate as the curing agent. The effects of the levels of silicone monomer and hydroxyl values on the film properties of the 2K WBPU coatings were investigated. Infrared spectroscopy characterized its structure. Scanning electron microscopy (SEM), thermo-gravimetric analysis (TGA), and differential scanning calorimetry (DSC) were used to study the surface morphology and the thermal stability of the film. The results showed that the performance of the coatings and the thermal stability of the film of 2K WBPU were improved after silicone modification.     

Preparation and properties of polyurethane coatings based on acrylic polyols and trimer of isophorone diisocyanate

This paper presents a study on the effect of NCO/OH ratio and an increase in hydroxyl content of acrylic polyols on the properties of polyurethane (PU) coatings. Coating properties studied are gloss, scratch resistance, flexibility and adhesion, mechanical properties include tensile strength, modulus, percent elongation and Shore hardness, while physicochemical properties include chemical resistance and solvent absorption of coated PU samples. A series of acrylic polyols (copolymers) based on butyl acrylate (BA), methyl methacrylate (MMA), styrene and 2-hydroxy ethylacrylate (HEA) were prepared by selecting different percentage of hydroxyl content. Trimer of isophorone diisocyanate (IPDI) was also synthesized in the laboratory. This trimer has trifunctionality. Isocyanurate ring of trimer increases thermal properties of PU. Polyurethanes from these acrylic polyols (containing different percent hydroxyl) and trimer of IPDI were prepared with two different NCO/OH ratios viz, 1.1:1 and 1.2:1. Polyurethanes were coated on substrates for measuring coating properties. Mechanical properties were measured on cast films of the PUs. The experimental results revealed that all polyurethane coatings based on acrylic polyols and IPDI trimer showed good gloss, scratch resistance and excellent adhesion. Thermal stability of these PU samples was found to be better. Physicochemical properties reflected that these PU have excellent chemical and solvent resistance.     

EIS study on failure process of two polyurethane composite coatings

The performance of acrylic polyurethane composite coating and aliphatic urethane composite coating in 3.5% NaCl solution under ultra-violet radiation was studied with methods of EIS, SEM and FTIR. For aliphatic polyurethane coating, the coating resistance decreased and the coating capacitance and porosity increased more quickly than acrylic polyurethane coating. The acrylic polyurethane composite coatings showed better performance than aliphatic polyurethane composite coatings. IR spectra showed that under UV irradiation conditions, the failure mechanism of the two polyurethane coatings was the transformation of sec-amide to primary amides. The fractured bonds in acrylic polyurethane were mainly C–O bonds, while in aliphatic polyurethane they were mainly C–N bonds. The lower protection property of aliphatic polyurethane coating may be mainly attributed to the C–N bonds which are more liable to be broken.     

Optical and mechanical properties of transparent acrylic based polyurethane nano Silica composite coatings

The aim of this work is to investigate the effect of two types of nano Silica (precipitated and fumed) with various concentrations on the optical and mechanical properties of transparent polyurethane acrylic based nano composite coatings. Transparency, gloss, UV absorption, adhesion strength and impact resistance of the samples have been measured. The gloss of the film samples remains unchanged compared to the reference film sample up to 2 wt.% (weight percent) for both types of nanoparticles. The samples containing 4 and 6 wt.% nano Silica show reduction in the gloss property by 4.3% and 5.3%, respectively, for fumed samples and 1.8% and 23% for precipitated samples. The film samples show increase in light absorption in the wavelength region of 250–2000 nm by increasing the content of nano Silica. Also cross cut and pull-off test results show that a good adhesion to steel can be obtained (5B for cross-cut, 7 MPa for pull-off) and no changes in impact strength of the samples with respect to the reference have been observed.     

Preparation of acrylic copolymer latex modified by fluorine,silicon, and epoxy resin

A series of modified acrylic copolymer latices have been prepared through a semicontinuous emulsion copolymerization process with a variety of hydrocarbon monomers and (perfluoroalkyl) methyl methacrylate, vinyltriethoxysilicone, and phenol‐formaldehyde epoxy resin. The composition of copolymer was analyzed by fluoride ion selective electrode analysis, ¹⁹F NMR, FTIR, crosslinking degree determination, and epoxy‐acetone method. The results showed that the fluorine monomer, silicon monomer and epoxy resin had copolymerized with acrylic monomers. The optimum mass ratio between the curing agent TEA and epoxy resin was 1.36 : 6. The determination results of stabilities (electrolyte stability, freeze‐thaw stability, high temperature stability and mechanical stability) of latices showed that the incorporation of fluorine monomer and silicon monomer improved freeze‐thaw stability and mechanical stability, whereas the epoxy resin did not have obvious effect on the stabilities. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Effects of additives on the performance of two-component waterborne polyurethane coatings

The effects of various additives and solvents on a coating’s performance in a two-component waterborne polyurethane coating system are studied using a statistical experimental design method. Using a blocked arrangement of fractional factorial design matrices, six different independent variables, including the use of different additives, catalysts, as well as solvents at different levels, were examined for their effects on various coating performance parameters, such as gloss, hardness, viscosity, and chemical resistance. Statistical analysis revealed several significant effects of these additives on the coating performances. Most importantly, several two-factor interactions between additives were also found to significantly influence the performance properties of the coating. These interactions could be very difficult to detect using traditional one-at-a-time experimental approaches. The information obtained from this study could be used for designing coating systems with superior performance properties. Presented at the 26th International Waterborne, High-Solids and Powder Coatings Symposium, February 10–12, 1999, New Orleans, LA. Coatings and Colorants Division, 100 Bayer Rd., Pittsburgh, PA 15205-9741.     

硅基和氨酯基协同改性水性丙烯酸树脂制备与性能

以γ-巯基丙基三乙氧基硅烷（TMPS）、异佛尔酮二异氰酸酯（IPDI）、甲基丙烯酸羟乙酯（HEMA）为原料合成了含硅聚氨酯小分子预聚体（IPDI-Si）。接着，以丙烯酸酯类单体为原料与IPDI-Si共聚，异丙醇（IPA）为溶剂，偶氮二异丁腈（AIBN）为引发剂，制备出巯基硅改性树脂聚合物。然后，以三乙胺为中和剂，加水乳化制备了一系列巯基硅聚氨酯改性水性丙烯酸树脂分散体。采用FTIR，XPS，TGA，TEM，SEM等对分散体及树脂膜材料进行了表征，并测试了分散体的贮存稳定性及胶膜的硬度、附着力等性能。结果表明，当IPDI-Si加入量为3%（以聚合单体的总质量为基准，下同）时，树脂分散体贮存稳定性较好，涂膜性能最佳；涂膜的致密性优异，硬度为2 H，附着性为1级，水接触角96.1 °。涂膜的拉伸强度达到9.4 MPa，断裂伸长率为385%；热失重分析表明，质量损失10%时的热分解温度（T10%）达到306.1 ℃。     

Ageing behavior of acrylic polyurethane varnish coating in artificial weathering environments

Polyurethane-based coatings reinforced by ZnO nanoparticles (about 27 nm) were prepared via solution blending. The ZnO/PU films and coats were fabricated by a simple method of solution casting and evaporation. The mechanical properties of the films were investigated by a universal material test, and the abrasion resistance of the prepared coats was evaluated by a pencil-abrasion-resistance tester. It was found that significant improvement of the PU films in Young’s modulus and tensile strength was achieved by incorporating ZnO nanoparticles up to 2.0 wt%, and that the abrasion resistance of the PU coats was greatly enhanced due to the addition of ZnO nanoparticles. Moreover, the antibacterial property test was carried out via the agar dilution method and the result indicated that PU films doped with ZnO nanoparticles showed excellent antibacterial activity, especially for Escherichia coli.     

Effects of ZnO nanoparticles on the mechanical and antibacterial properties of polyurethane coatings

Polyurethane-based coatings reinforced by ZnO nanoparticles (about 27 nm) were prepared via solution blending. The ZnO/PU films and coats were fabricated by a simple method of solution casting and evaporation. The mechanical properties of the films were investigated by a universal material test, and the abrasion resistance of the prepared coats was evaluated by a pencil-abrasion-resistance tester. It was found that significant improvement of the PU films in Young’s modulus and tensile strength was achieved by incorporating ZnO nanoparticles up to 2.0 wt%, and that the abrasion resistance of the PU coats was greatly enhanced due to the addition of ZnO nanoparticles. Moreover, the antibacterial property test was carried out via the agar dilution method and the result indicated that PU films doped with ZnO nanoparticles showed excellent antibacterial activity, especially for Escherichia coli.     

Preparation and properties of fluorinated silicon two‐component polyurethane hydrophobic coatings

A polyurethane (PU) hydrophobic coating was prepared by the two‐component method, polycarbonate diol and isophorone diisocyanate becoming a two‐phase composition. The PU films with hydrophobic surface were prepared by establishing a rough structure on the surface of silica (SiO₂) modified with silane coupling agents (γ‐(2,3‐epoxypropoxy)propytrimethoxysilane (KH560) and (heptadecafluoro‐1,1,2,2‐tetradecyl)trimethoxysilane (FAS)). First, the surface of SiO₂ was covered by a layer of hydrophobic methyl and fluorocarbon (C–F) groups. Then, the SiO₂ and modified SiO₂ were obtained by the introduction of KH560 and FAS with the silanol reaction by ultrasonic stirring. The effect of SiO₂ and modified SiO₂ on the structure and hydrophobic properties of PU was investigated by a series of test instruments. The results showed that the introduction of SiO₂ and modified SiO₂ was beneficial for increasing the roughness of the PU coating surface; the roughness of FAS/SiO₂‐PU could reach up to 14.790 nm, four times better than pure PU. A hydrophobic modified PU coating with water contact angle 123° was fabricated by using the hydrophobic C–F group FAS as a low surface energy material and establishing a micro rough structure on the surface of PU. Moreover, PU modified with KH560 and FAS can reduce the glass transition temperature (T_g) of soft segments, resulting in improvement of micro‐phase separation. © 2020 Society of Chemical Industry     

丙烯酸/蓖麻油聚氨酯耐磨涂料的研究

介绍了丙烯酸/聚氨酯涂料的制备和性能测试工艺流程以及蓖麻油改性TDI制备聚氨酯、丙烯酸树脂和丙烯酸改性聚氨酯涂料的合成步骤。通过正交实验对羟基丙烯酸树脂和耐磨性填料———二硫化钼、氧化铬和聚四氟乙烯的用量进行了优化,获得了涂料的最优化配方(用质量分数表示):A组分:聚氨酯3%,醋酸丁酯3%;B组分:羟基丙烯酸1.5%,二硫化钼0.3%,三氧化二铬0.4%,聚四氟乙烯0.6%,混合溶剂5%,十二烷基硫酸钠0.12%,KH-5500.025%,二丁基二月桂酸锡0.0125%。所得涂膜的表干时间约为30min,实干时间约为36h。涂层的附着力1级,硬度1B。在3.3kg的载荷下,磨轮旋转1500圈后,涂层磨痕弦长6.5mm,说明涂料耐磨性优良。试样在质量分数分别为5%和15%的盐酸、氢氧化钠溶液中浸泡一周后,涂层无起泡、润胀和脱落现象,说明涂层耐蚀性优良。     

Effect of surface microstructure on the hydrophobicity of coatings

In this paper, coatings adopted SiO₂ nanoparticles ranging from 1 wt% to 7 wt% were in situ polymerized with low surface energy polymer, and different surface microstructures were built automatically during painting film. Copper microstructure surface was also achieved by chemical etching method and then was modified by low surface energy resin as contrast. The contact angle and the peel strength between the coating and bio-gooey simulacrum were studied. The results showed that the hydrophobicity of the coating was remarkably affected by the surface microstructure. The coating containing 5 wt% SiO₂ nanoparticles was covered with micro- and nano-scale salience and holes, and had the maximum contact angle and the minimum peel strength. Copper slices presented uniform micron and sub-micron structure surface when etching for 15 min and the contact angle reached a maximum of 125° after being modified.     

Tuning the mechanical performance and adhesion of polyurethane UV cured coatings by composition of acrylic reactive diluents

An approach to modify the properties of UV curable polyurethane coatings by altering the amount and functionality of acrylic reactive diluents, in order to optimize the coating performance, is demonstrated. Based on the rheology analysis, a model of the rheological behavior of the UV curable materials depending on the amount and type of a reactive diluent in the composition is demonstrated in this study. The relationships between the rheological behavior, the mechanical properties and adhesion of the coatings prepared from polyurethane UV curable compositions containing different amounts and functionalities of acrylic reactive diluents, have been investigated and discussed in this study. Based on the results of the study, the desired properties of UV cured coatings can be modeled and controlled without changing the nature of a particularly selected oligomer, thus maintaining the advantages of its chemical structure in a coating composition.