电子束固化木器清漆的制备及性能研究

电子束(EB)固化技术作为一种重要的辐射固化技术,其固化的清漆涂层性能在许多方面优于紫外(UV)光固化清漆涂层。本研究通过选取不同类型的商品化丙烯酸树脂及活性稀释剂配制木器涂料配方,分别利用电子束(EB)和紫外光(UV)对其进行固化,然后对固化后的涂层进行基本性能、热性能和机械性能的表征。研究结果表明:EB固化速度快,固化膜具有较高的铅笔硬度和附着力,而且树脂种类和单体结构的不同会对电子束固化涂层的热性能及机械性能产生影响。     

UV Curable Acrylate Nanocomposites: Properties and Applications

Transparent nanocomposites were prepared from nano-sized silica and radiation curable acrylates. To improve the embedding of silica nanoparticles within the acrylate matrix the filler surface was modified by trialkoxysilanes. Instead of an expected monomeric silane grafting polysiloxane structures were anchored on the nanoparticle surface due to acid catalyzed pre-hydrolysis/condensation of trialkoxysilanes. The polysiloxanes structures covering the silica surface were characterized by temperature-programmed oxidation, infrared and multinuclear MAS NMR spectroscopy. MALDI-TOF mass spectroscopy revealed the formation of polysiloxane oligomers with more than 20 monomeric silane units. Ladder-like polysiloxane chains have been proposed and atomic force microscopy were used to visualize the structure of surface-anchored organosilanes. These ladder-like structures are assumed to build up a short range interpenetrating network with polyacrylate chains during UV or EB curing.Due to the organophilic modification of silica nanoparticles reinforced acrylate formulations can contain up to 50 wt.-% nanofiller maintaining satisfactory rheological properties. These formulations can be used as coatings on substrates such as polymer films, paper, metal, wood, engineered wood, etc. After UV/EB curing nanoparticle reinforced polyacrylate coatings are obtained which show markedly improved properties as compared to neat polymers, e.g., increased microhardness and modulus, improved scratch and abrasion resistance, higher gas barriers and temperature resistance. Due to the nano-sized silica filler the cured coatings remain transparent, hazeless and glossy.On a pilot scale unit acrylate nanocomposite coatings are manufactured for roll coating, curtain coating and spray applications. Basic properties of acrylate nanocomposite coatings are described.     

Corrosion protection of galvanized sheet by maleic anhydride-g-liquid polybutadiene environmental friendly coatings

Maleic anhydride-g-liquid poly(1,2-butadiene) (MALPB) was modified with diethanolamine (DEA) to prepare anticorrosive coatings by using ethylene glycol monobutyl ether as non-volatile diluents which was considered environmental friendly; their curing processes and anticorrosive performances on galvanized sheet were studied. A robust coating could be obtained through the crosslinking reaction among hydroxyl groups and acids groups, as well as the crosslinking reaction of double bonds by adding peroxides including 0.25% benzoyl peroxide and 1% dicumyl peroxide (wt% of MALPB) as initiators. The Fourier transforming infrared (FTIR) spectra and differential thermo analysis (DTA) results showed that the coatings could be effectively cured at around 260 °C in 5 min. These coatings exhibited good flexibility and adherence on galvanized sheet while their adhesion decreased with the addition of pigments as observed by the digital microscope. As anticorrosive layers on galvanized sheet, these coatings provided effective barriers to electrolyte by impeding their contact with the metal surface; and their anticorrosive capability could be improved by the addition of pigments as observed through the DC polarization tests and salt spray tests.     

The influence of zinc surface pretreatment on the adhesion of epoxy coating electrodeposited on hot-dip galvanized steel

The adhesion and electrochemical properties of epoxy coatings electrodeposited on hot-dip galvanized steel with and without passive films were investigated during exposure to 3% NaCl. The passive films were formed in hot air, in boiling water and by chromating. Adhesion was measured both by a standardized pull-off method and by swelling in N-methyl pyrrolidone. Pretreatment of hot-dip galvanized steel with passive film formed in hot air increases both dry and wet adhesion strength of the epoxy coating compared to pretreatment with passive film formed in boiling water and chromate coating. The overall increase of wet adhesion for this sample was maintained throughout the whole investigated time period. It was shown that the change in adhesion of epoxy coating on a chromate coating is smallest of all investigated samples, although the initial value of adhesion on this surface had the lowest value. The corrosion stability of coated Zn samples pretreated by different methods, was investigated by electrochemical impedance spectroscopy and in the initial time of exposure to NaCl the highest values of pore resistance were also obtained for the epoxy coating on Zn pretreated in hot air, whereas the epoxy coating on a HDG steel with a chromate coating showed the smallest change in electrochemical properties (pore resistance, coating capacitance, charge-transfer resistance) during prolonged exposure time.     

提高紫外光固化涂料对塑料底材附着力的探讨

紫外光固化涂料在表面自由能低的塑料底材上附着极为困难。讨论了紫外光固化涂料所用单体及用量、交联单体、施工温度、涂料固化程度、底材表面处理方法等因素对涂膜在塑料底材上附着力的影响。     

Epoxysilane as adhesion promoter in duplex system

Coatings are one of the most used protection methods for metals. Metallic coatings, such as zinc and its alloys, are used to protect steel in mild corrosive environments. In aggressive environments, on the other hand, organic coatings must be employed in the so-called duplex systems. However, the galvanized steel/organic coating adhesion is a problem and many attempts had been done to solve it with the incorporation of a chromate-based or phosphate-based interlayer. Nowadays, the use of these compounds is questioned due to their environmental impact and new adhesion promoters, like silanes, are being investigated. The aim of this paper was to study the adhesion and the anticorrosive behavior of a duplex system with a layer of glycidoxypropyltrimethoxysilane (γ-GPS) between the zinc and the coating. Polarization tests and corrosion potential measurements were done on the γ-GPS/galvanized steel to select the better anticorrosive pretreatment conditions for the application of an organic traditional paint. Dried and wet adhesion of the coating to the pretreated substrate was studied by the standard tape test. Salt spray test and electrochemical noise technique were employed to study the corrosion behavior of the duplex systems. Results showed that the films of γ-GPS formed on galvanized steel diminished the corrosion current of the metal, but they do not protect the substrate by a barrier effect. The incorporation of the pretreatment in the duplex system increased the adhesion of the paint, especially when the pretreated substrate was cured 1?h at 200?°C.     

预磷化电镀锌钢板粉末喷涂前处理工艺

对一种用于汽车和通讯行业的新型预磷化镀锌钢板的粉末喷涂前处理工艺进行了研究,通过晶相、膜质量及盐雾试验,对预磷化板的现有工艺进行了改进。酸洗工艺对预磷化板是不利的,酸洗工艺完全破坏了预磷化膜层。盐雾试验结果表明,预磷化镀锌钢板经过弱碱性脱脂剂清洗,经表调、磷化然后和粉末涂料结合,可以得到良好耐蚀性和附着力强的涂层。     

低能电子束辐射固化涂料的研究

以低能电子束处理多种配方的涂料,研究了辐射剂量、加速电压和氧气浓度对涂料固化性能的影响。结果表明：氧气浓度高于一定程度时将会导致涂层固化困难,辐射剂量对涂膜性能有着直接的影响,较高的加速电压有利于较厚涂层的固化。并对EB固化与UV固化后的涂膜性能进行了对比测试,表明EB固化涂料在性能上存在明显的优势。     

Towards anti-corrosion coatings from surfactant-free latexes based on maleic anhydride containing polymers

We report on the film formation of surfactant-free, artificial latexes based on copolymers containing maleic anhydride. Different metallic substrates, such as aluminum, steel and magnesium alloys, were coated with three different latexes. A commercial polyester based coating was used as a comparative sample. Two of the latexes were based on polymer with a high T_g (resp. 100 and 130 °C), and one on a polymer with a T_g of −70 °C. The wetting of the substrates could be optimized by etching the metal substrate, acidic or alkaline, leading to homogenous film formation and improved adhesion. For aluminum substrates an alkaline pretreatment improved the adhesion with the polymer films, whereas for magnesium the acidic pretreatment improved the adhesion. Furthermore, acid pretreatment increased the corrosion resistance of the coated magnesium substrate, when compared to an alkaline pretreatment. The films formed from latex displayed comparable or better anti-corrosive properties when compared to the commercial polyester.     

附着力促进剂对光固化金属涂层附着力提升的研究

为了探究附着力促进剂对光固化金属基涂层附着力的影响，本文通过划格法、拉拔法及搭接剪切实验，系统研究了磷酸酯类附着力促进剂、硅烷偶联剂对光固化金属基（低碳钢、铝板）涂层附着力的促进作用。结果表明：磷酸类附着力促进剂能够显著提高光固化金属基（低碳钢、铝板）涂层的附着力，而硅烷偶联剂对光固化金属基（低碳钢、铝板）涂层的附着力无明显提升作用。     

X80钢管防腐环氧粉末涂层技术的研究

重点阐述采用自主合成的Amanda979系列固化剂,优选环氧树脂辅助填料、助剂等材料,制成X80钢管防腐环氧粉末涂料。试验结果表明:X80钢管防腐环氧粉末涂料180～185℃能在2～3min快速固化、具有卓越的附着力、耐高温阴极剥离(经过1.5V/65℃的阴极剥离试验30d,阴极剥离半径为<10mm),符合新的FBE管道防腐涂层(简称HCD-FBE)技术要求。     

热镀锌燃气管道外用环氧防腐涂料的制备及性能研究

探讨了不同种类的环氧树脂、不同种类的胺固化剂以及颜基比对热镀锌管基材涂层附着力、铅笔硬度、耐冲击性、耐酸性等性能的影响。研究表明:环氧树脂E-20-聚酰胺125体系可以降低涂层干燥时间,提高涂层在热镀锌管表面耐冲击性能至123.5 cm,同时耐酸试验后耐冲击性能仍达到95.5 cm;当涂层颜基比控制在1.8∶1时,涂层的综合性能达到最佳,耐酸试验前后各项性能均未下降,附着力均达到0级,耐冲击性能均达到162.5 cm。最终选用环氧树脂E-20为基体树脂,聚酰胺125作为固化剂,以1.8∶1的颜基比制备了一种适用于热镀锌燃气管道外用防护涂料,该涂料各项性能均明显优于CGAS001—2016《宽边管件连接涂覆燃气管道技术规程》中对环氧树脂涂料及涂层的技术要求。     

金属用紫外光固化涂料的研发

针对紫外光固化涂料存在与金属基材附着力差的问题，考察了如预聚体、活性稀释剂、附着力促进剂、固化工艺及预处理等因素对涂膜附着力的影响。试验及应用结果表明：合理搭配上述各因素能够有效改善涂膜对金属基材的附着力。     

室温固化硅酸盐耐高温防腐蚀涂料

制备了一种室温固化的硅酸盐耐磨防腐涂料,该涂料具有优异的耐磨防腐蚀性能,能广泛应用于金属、陶瓷、塑料、玻璃等材料表面,并且具有良好的附着力和匹配性,该涂料固化后还具有低的介电常数。     

AFM Scratching for Adhesion Studies of Thin Polymer Coatings on Steel

Abstract

Atomic force miscroscopy (AFM) scratching at constant applied forces was used to quantify the adhesion of polymer coatings to cold rolled steel (CRS) and to study the effectiveness of a pretreatment for improving the adhesion. The pretreatment was a phosphate-free zirconia-based coating. Thin layers of commercially available epoxy, acrylic and polyester-based polymer coatings, were applied to polished or pretreated cold rolled steel substrates and the surface was scratched at the edge of the polymer coatings with the AFM tip at increasing values of normal loads until the coating was removed. Adhesion strengths were determined from the minimum tip-sample interaction force and number of cycles (scans) at a particular applied force. The pretreatment significantly improved adhesion of the epoxy and acrylic-based coatings on CRS. Adhesion of the acrylic-based coating was found to be better than the epoxy coatings on the bare as well as pretreated steel. Adhesive strength of the polyester-based coating was inconclusive because it was very easily removed on application of small forces using the AFM tip. The AFM scratching technique was found to provide a quick, easy and effective way to make quantifiable comparisons in relative adhesive strengths of polymer coatings and the effect of pretreatments.     

封闭型异氰酸酯固化马来酸酐聚丁二烯水性涂料的研究

以马来酸酐化低分子聚丁二烯(MALPB)为原料,通过加入过氧化物和封闭型异氰酸酯Bayhydur BL5140双固化剂体系制备了耐腐蚀性能优异的水性涂料,研究了双固化剂体系中封端型异氰酸酯固化剂BL5140对水性涂料的固化过程和性能的影响。试验结果表明:涂层厚度为20μm;硬度为3H～4H;附着力为0～1级。BL5140的加入可大幅提高涂层的耐热性能;而且BL5140的加入可提高镀锌板、镁合金的自腐蚀电位而对金属表面起到很好的保护作用,盐雾试验也表明该涂料耐蚀性能突出。     

Adhesion characterization of protective organic coatings by electrochemical impedance spectroscopy

Adhesion is considered in many situations to be a very important property of organic coatings for corrosion protection and much scientific work is devoted both to the study of the mechanism involved in polymer-metal adhesion and to the ways of measuring this property. The large number of experimental methods in existence to obtain information on coating adhesion is an indication of both the scientific and the technological interests in this material science and engineering area, but it is also a consequence of the difficulty in measuring adhesion in a general sense. As a partial alternative to the traditional adhesion measurement approaches for organic coatings, the evaluation of adhesion by electrochemical techniques such as electrochemical impedance spectroscopy (EIS) is discussed for different examples. The influences on adhesion of different pretreatments or organic coatings are discussed, considering aluminium, galvanized steel, and stainless steel substrates, and we have shown that the information obtained by using an electrochemical approach can be used for adhesion evaluation, with particular attention to the monitoring of adhesion in an aqueous environment, which is the most detrimental for protective organic coatings.     

固化剂对环氧玻璃鳞片涂层性能的影响

以双酚A环氧树脂(E20)为主要成膜物,层片状玻璃鳞片和云母氧化铁为主要填料,辅助以铝粉、氧化铁红颜料,以及各种助剂和溶剂,再分别加入固化剂脂肪族胺加成物、聚酰胺TY-650,制得高固体分厚浆型环氧玻璃鳞片涂料。通过常规的力学性能(涂层的硬度、耐冲击性、柔韧性、附着力等)和耐腐蚀性测试,对比了不同固化剂对环氧玻璃鳞片涂层性能的影响。研究结果表明,脂肪族胺加成物与环氧树脂交联固化的玻璃鳞片涂层的硬度、附着力以及交流阻抗值都较高,具有良好的综合性能,加入铝粉对基体可起到阴极保护作用。     

卡纸涂层对EB固化直接真空镀铝工艺的影响

通过改变卡纸涂布量和涂层中瓷土与碳酸钙的比例,研究了卡纸涂层对电子束固化直接真空镀铝工艺的影响。结果表明,随卡纸涂料量提高,表征涂层开放程度的油墨吸收性也随之提高,但卡纸的耐折性能则下降,电子束（EB）固化预涂料涂布量也随之增大;卡纸涂层材料中颜料的组成对卡纸性能及EB固化涂料预涂量有影响,随着颜料中瓷土含量降低,碳酸钙含量提高,涂层的开放程度提高,纸张光泽度下降。     

Acrylated lesquerella oil in ultraviolet cured coatings

A triglyceride of hydroxy fatty acids, lesquerella oil (LO), was structurally modified and used for the first time in the design, synthesis and evaluation of UV cured coatings. The results demonstrate that LO derivatives improved adhesion to metal substrates. For instance, methacrylated LO significantly improved adhesion to steel, and hydroxyethylmethacrylated LO improved adhesion to steel and aluminum substrates. The use of LO derivatives slightly lowered crosslink density and solvent resistance, and increased flexibility at the expense of T_g.