紫外光固化粉末涂料

紫外光（UV）固化粉末涂料综合了传统粉末涂料和辐射固化技术诸多优点，是涂料工业的前瞻性产品。本文介绍了紫外光固化粉末涂料的配制，固化机理，涂装工艺及潜在应用，并对其最新研究进展进行了综述。     

有机磷系及石墨烯阻燃环氧树脂研究进展

环氧树脂作为一种优异的树脂基体,被广泛地应用于众多领域,但因其极易燃烧,所以常常需要对其进行阻燃处理。本文简要综述了近几年有机磷系化合物及石墨烯阻燃环氧树脂的研究进展,其中有机磷系化合物阻燃部分重点介绍了以阻燃剂中间体9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)及其衍生物和聚磷酸铵(APP)为代表的含磷阻燃剂在环氧树脂中的阻燃机理和阻燃进展;同时也介绍了石墨烯及其衍生物在环氧树脂阻燃领域的最新研究进展,并对其发展前景进行了展望。     

非等温DSC法研究甲壳型液晶PBPCS改性环氧树脂的固化动力学

采用非等温DSC法对聚乙烯基对苯二甲酸二(对丁氧基苯酚)酯(PBPCS)/环氧树脂/甲基四氢苯酐固化体系的固化反应热行为以及固化动力学进行了研究,分别利用Kissinger和Ozawa动力学模型计算得到各体系固化反应的表观活化能,利用Crane模型计算出固化反应级数,得出了适于该树脂体系固化反应过程的动力学方程.结果表明该体系固化反应按照一级反应进行,PBPCS的加入不改变环氧树脂的固化机理,甲壳型液晶高分子PBPCS可以用于环氧树脂的改性研究.通过固化体系的DSC分析确定了体系固化工艺为90℃/2h→120℃/2h→140℃/1.5h,为聚乙烯基对苯二甲酸二(对丁氧基苯酚)酯/环氧树脂/甲基四氢苯酐体系的固化、性能测试和应用提供了理论依据,也为甲壳型液晶高分子改性环氧树脂的研究提供一定理论基础.     

DAIP改性环氧树脂研究

采用共固化的方法,得到酚醛环氧树脂(F-51)和间苯二甲酸二烯丙基酯(DAIP)的共固化树脂。实验结果表明:DAIP的加入降低了F-51环氧树脂的粘度[体系粘度为150～350mPa·s(25℃)],利于工艺操作;提高了F-51环氧树脂的耐热性,热变形温度达200℃。研究了F-51环氧树脂和DAIP共固化的固化行为、不同配比对共固化物形态结构的影响;并研究了不同配比对固化物耐热性的影响。     

螺环原酸酯改性环氧树脂的研究

合成了一个新的螺环原酸酯单体,即带有螺环原酸酯结构单元的环氧树脂（Ｅ ５４）．用该单体对环氧树脂进行改性,可以减少残留在树脂基体中的环氧基团,这说明该单体与环氧树脂之间发生了共聚固化反应．基体的Ｔｇ和热稳定性随预聚物加入量的增加而降低,但改性环氧树脂的粘接强度则随预聚物的加入量的增加而增加．对上述试验观察到的现象进行了讨论,并测试了改性环氧树脂基体的力学性能．     

液晶环氧树脂复合材料的研究进展

综述了液晶环氧树脂复合材料的国内外研究进展，介绍了液晶环氧树脂复合材料的种类和各种液晶环氧树脂复合材料的性能，并简述了液晶环氧树脂复合材料研究发展方向。     

环氧树脂水性化体系研究进展

系统地介绍了目前国内外环氧树脂水性化的研究进展,总结了环氧树脂水性化体系的特点与应用,并提出一种水性环氧树脂乳液制备的新方法。     

环氧树脂/层状无机物纳米复合材料

概述了近年来国内外环氧树脂／层状无机物纳米复合材料的研究现状，详细介绍厂环氧树脂／蒙脱土、环氧树脂／水滑石及环氧树脂／石墨三种代表性环氧树脂纳米复合材料的制备、性能及研究进展。     

弹性体增韧环氧树脂研究进展

聚氨酯和丁腈橡胶是两种对环氧树脂增韧效果显著的橡胶弹性体,文章分别介绍了这两种弹性体增韧改性环氧树脂的机理和近年来的主要研究进展,并讨论了聚氨酯增韧环氧树脂和丁腈橡胶增韧环氧树脂各自的特点,展望了弹性体增韧环氧树脂的前景。     

含氮杂环结构的阻燃环氧树脂基电子材料

“无卤无磷无铅”的绿色阻燃环氧树脂基电子材料是既能满足阻燃功能、又需符合环保要求的热固性（复合）材料,是目前阻燃热固性树脂领域的重点和难点课题。有机氮杂环作为一类高效、低毒的阻燃结构,可以共价引入至环氧树脂中,但至今还未建立系统的氮杂环的结构与其阻燃性能的关系。本文结合本课题组近十年的研究工作,综述了近年来国内外含氮杂环阻燃环氧树脂的研究进展,讨论了不同含氮杂环结构（三嗪环、异氰脲酸酯环、二氮杂萘酮、酰亚胺、苯并 NFDA1 嗪和海因环等）环氧树脂固化物的制备方法,给出了定量的结构与性能关系。利用共价键法将含氮杂环结构引入环氧树脂体系中,在实现阻燃功能的同时也能保持材料的综合性能,甚至可提高环氧树脂固化物的热稳定性能,因而制备含氮杂环结构的环氧树脂是“无卤无磷无铅”绿色阻燃的重要解决方案。但是,目前仅依靠含氮杂环结构很难达到理想阻燃效果,大部分已报道的体系只能达到 “无卤无铅少磷”的水平,仍需要进一步深入研究和认识含氮杂环结构的阻燃环氧体系的结构-性能关系,并提出提高含氮杂环体系阻燃效果可能的解决方法。     

Effect of molecular structure of epoxy oligomers with perfluorinated fragments on hydrophobic properties of powder coatings

An effect of the chemical structure of a series of the synthesized epoxy oligomers with perfluorinated fragments on the surface and mechanical properties of thermosetting powder coatings based on epoxy compositions was investigated. The possibility of their use as modifiers for effective hydrophobic epoxy coatings with a high level of physical and mechanical properties was demonstrated.     

New powder coatings with low curing temperature and enhanced mechanical properties obtained from DGEBA epoxy resins and Meldrum acid using erbium triflate as curing agent

New low curing temperature powder coatings obtained by copolymerization of epoxy resins with Meldrum acid (MA) initiated by erbium (III) trifluoromethanesulfonate have been formulated. Their mechanical and thermomechanical properties have been studied and compared with a commonly used industrial system (o-tolylbiguanide/epoxy resin) and with an already formulated epoxy powder coating homopolymerized by erbium trifluoromethanesulfonate. Systems containing low proportions of MA and initiated by erbium trifluoromethanesulfonate lead to a great reduction of curing conditions (temperature/time). Moreover, the new formulated systems present very good mechanical properties, adhesion, and impact resistance. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2316–2327, 2007     

Crosslinking kinetics studies on interpenetrating polymer network powder coatings

IPN powder coatings were prepared which were composed of (A) a pendant double bond-containing acrylic resin made by reacting m-isopropenyl-α-α-dimethylbenzyl isocyanate (TMI) and a hydroxyl-containing acrylic resin and (B) a bisphenol type epoxy resin of high molecular weight cured by means of a carboxylic acid-containing acrylic resin. Crosslinking kinetics studies were carried out by using a computerized differential scanning calorimeter (DSC). A computer program was designed to simulate the curing reactions of the IPN powder coatings by using the individual kinetic parameters obtained from DSC. The simulated results from the computer program are very close to the results from experimental thermograms (by DSC). Therefore, this methodology provides an efficient tool to simplify and predict kinetic studies of crosslinking reactions in current or new IPN powder coating systems.     

Powder coatings for corrosion protection

Powder coatings found a wider use in corrosion protection of steel structure. In Europe very often double-layer systems are used, based on an adhesion promoting epoxy (EP) primer and a weathering stable top coat, mostly polyester (SP) sometimes EP/SP-hybrid powders. An interesting development is the use of zinc filled EP powders as primer to offer a cathodic protection to the steel surface. Powder systems with and without zinc were compared to proved coating systems based on liquid paint materials, where powder coating systems showed results comparable to these systems. Besides many advantages of powder coatings for corrosion protection there are still some problems. The workshops carring out the powder coating have to be in control of the surface pretreatment like chromating, but espescially phosphating and the work with the chromate-free pretreatment methods for galvanized steel. As always in the field of corrosion protection it is the surface pretreatment and preparation which determines the quality of the whole coating system decisively. This problem can be solved by appropriate working. In some years the problem with the general maintenance of powder coatings after weathering and ageing will be actual. This problem should be solved because of the homogeneous coatings on larger areas. Of importance will be the adhesion on the old coating and the appearance of the maintenance coating. The touch up of smaller parts as transport damages will be much more difficult in order to the appearance.     

Anchoring calcium carbonate on graphene oxide reinforced with anticorrosive properties of composite epoxy coatings

Calcium carbonate nanoparticles (nano‐CaCO₃) anchored graphene oxide (GO) sheet nanohybrids (GO‐CaCO₃) are fabricated, and their structure can be measured by scanning electron microscope, transmission electron microscopy, X‐ray photoelectron spectroscopy, X‐ray diffraction and Fourier‐transform infrared spectroscopy analysis. Afterwards, composite epoxy coatings, filled with GO and GO‐CaCO₃ nanohybrids, are prepared via a curing process. The dispersion and anticorrosive properties of composite epoxy coatings are investigated. The results reveal that GO‐CaCO₃ nanohybrids achieve a homogeneous dispersion as well as reinforce corrosion resistance of epoxy coatings. Furthermore, the anticorrosive mechanisms are tentatively proposed for the GO‐CaCO₃/epoxy coatings. Copyright © 2016 John Wiley & Sons, Ltd.     

Adhesion between coating layers based on epoxy and silicone

The adhesion between a silicon tie-coat and epoxy primers, used in marine coating systems, has been studied in this work. Six epoxy coatings (with varying chain lengths of the epoxy resins), some of which have shown problems with adhesion to the tie-coat during service life, have been considered. The experimental investigation includes measurements of the surface tension of the tie-coat and the critical surface tensions of the epoxies, topographic investigation of the surfaces of cured epoxy coatings via atomic force microscopy (AFM), and pull-off tests for investigating the strength of adhesion to the silicon/epoxy systems. Calculations for determining the roughness factor of the six epoxy coatings (based on the AFM topographies) and the theoretical work of adhesion have been carried out. The coating surfaces are also characterized based on the van Oss-Good theory. Previous studies on the modulus of elasticity of the polymers involved have also been considered. It was found that adhesion problems might be due to inadequate wetting, the significantly different topographies, and differences in the mechanical strengths of the epoxies. Acid-base interactions calculated from the van Oss-Good theory were found useful in explaining the enhanced adhesion for some epoxy/silicon surfaces.     

Synthesis and properties of iron oxide coated carbon nanotubes hybrid materials and their use in epoxy coatings

Multi‐walled carbon nanotubes (MWCNTs) were acidified with nitration mixture, and the Fe₂O₃‐MWCNTs (iron oxide coated multi‐walled carbon nanotubes) hybrid material via sol‐gel method then verified the results through scanning electron microscope, X‐ray diffraction, and thermal gravimetric analysis. We modified the hybrid material with silane coupling agent (KH560), Fe₂O₃‐MWCNTs/epoxy, MWCNTs/epoxy composites coating, and the pure epoxy coatings were respectively prepared. The properties of the composite coatings were tested through the electrochemical workstation (electrochemical impedance spectroscopy), shock experiments, and thermal gravimetric analysis. Finally, we used scanning electron microscope to observe the surface conditions of the coatings. The results show that Fe₂O₃‐MWCNTs have good dispersion in the epoxy resin, and the Fe₂O₃‐MWCNTs/epoxy composite coatings have enhanced mechanical properties and corrosion resistance. Copyright © 2015 John Wiley & Sons, Ltd.     

Water sorption in UV degraded clear and pigmented epoxy coatings assessed by dielectric sorption analysis

Degraded clear and pigmented epoxy coatings were investigated by dielectric sorption analysis (DSA). Differences in dynamics of absorption, due to increased hydrophilicity, crosslinking and porosity, were found between UV degraded and undegraded epoxy coatings. Desorption was observed for longer degradation times, caused by swelling of the coating, squeezing out the excess of water. Model system measurements of pigmented coatings with various filters on top reproduced the desorption behaviour. Due to crack formation during DSA measurements, clear coatings showed fluctuating results, a result of release of tension of the UV degraded clear coating by humidified nitrogen. Pigmented coatings did not show this behaviour, resulting in an increasing water absorption trend with increasing degradation times. Larger desorption peaks were found for lower frequencies, indicating that either polarization takes place or water-hydrophilic interaction. Based on these results, DSA is suitable for non-destructive investigation of degraded coatings and paints.     

The coating performance of adipic acid modified and methacrylated bisphenol- A based epoxy oligomers

In the present work adipic acid modified and methacrylated bisphenol A based epoxy resins were prepared. The structures of oligomers were characterized by FT-IR. UV curable clear coatings were applied on aluminum substrates. The physical and mechanical properties of UV-cured coatings such as gel content, solvent resistance, hardness, gloss, flexibility and tensile tests were examined. In addition, the thermal behavior of coatings was also evaluated. It is observed that the tensile properties and thermal stabilities of modified epoxy methacrylate coatings mainly depend on the adipic acid content. The best results were obtained with 5 wt% adipic acid modification. Copyright © 2007 John Wiley & Sons, Ltd.     

Conductivity and electromagnetic shielding effectiveness of flaky Ni/Ni-Cu-coated glass fiber/epoxy resin composite coating

Flaky Ni/Ni-Cu-coated glass fiber/epoxy resin composite coatings were prepared using the glass fibers and flaky nickel powders as fillers and epoxy resin as binder. The conductivity and electromagnetic shielding effectiveness of the coatings are as follows: (1) the appropriate content of Ni-Cu-coated glass fibers is 6 wt % in the composite filler and the optimum ratio of the filler to epoxy resin is 4: 1; (2) electrical conductivity of the coating with a thickness of 300 μm has a minimum value of 0.72 Ω cm; (3) shielding effectiveness of the coatings is up to 50.21–55.43 dB in the frequency range of 0.3–1000 MHz. This offers a new idea to enhance the added value of the glass fibers and raise the level of electromagnetic radiation protection.