Preparation and coating properties of an acrylic melamine resin containing silicone segments

The aim of this study was the preparation of novel water repellent UV curable materials using acrylic modified melamine (AM) and poly-dimethylsiloxane (PDMS). UV curable acrylic melamines containing silicone segments (SiAMs) were synthesized by condensation of methylolmelamine, 2-hydroxyethyl acrylate, and carbinol-modified PDMS. The SiAM films with a 0.3 wt% PDMS segment that were cured by UV irradiation had higher transparency than that of a blended sample. Examination with a scanning electron microscope revealed that the blend sample has cohesion of the silicone segments, while such a phenomenon was not observed in the composite samples (SiAMs). From these results, it was confirmed that aggregation of the silicone segments was prevented by introducing the silicone segments into the acrylic melamine. By introducing 0.3 wt% of PDMS segments into AM, good water-shedding properties were confirmed, while several of the most attractive features of AM, such as hardness, adhesion, and refractive index, were maintained.     

Synthesis and application of acrylic colloidal unimolecular polymers as a melamine thermoset system

Acrylic polymers were synthesized with a ratio of 1 : 7 or 1 : 8 of acrylic acid to acrylic ester monomers to produce an acid‐rich resin. The polymers were water reduced and solvent was stripped to produce colloidal unimolecular polymers (CUPs). These particles were typically 3–9 nm in diameter depending on the molecular weight. They were then formulated into a clear coating with melamine as the crosslinker with thermal curing. Compared to commercial latex films, these melamine‐cured acrylic CUPs had a distinct advantage of having a near‐zero volatile organic compound, better availability of surface functional groups , and improved water resistance. The coatings were evaluated for their methyl ethyl ketone resistance, adhesion, hardness, gloss, flexibility, abrasion , and impact resistance properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40916.     

光敏氨基丙烯酸酯树脂的合成及其油墨应用

采用两步法合成了光敏性氨基丙烯酸树脂(β-丙烯酸羟乙酯改性三聚氰胺甲醛树脂,HEA-MF),考察了反应物配比、反应时间、催化剂等对合成反应的影响。采用红外光谱表征了产物的结构;通过DSC分析了羟甲化反应产物六羟甲基三聚氰胺的熔点;采用高压液相色谱仪(HPLC)测定了醚化产物的醚化度。获得的优化反应条件为:羟甲基化反应中三聚氰胺/甲醛物质的量比为1∶8,反应温度为70℃,反应时间为3.5 h,催化剂选用三乙胺;醚化反应温度105℃,反应时间5 h,催化剂为对甲苯磺酸。合成的HEA-MF贮存性能良好,游离甲醛含量低。将合成的HEA-MF作为活性稀释剂与酚醛环氧丙烯酸树脂复配成光固油墨,采用热失重分析仪(TGA)分析了HEA-MF含量和醚化度对涂膜的耐热性等性能的影响。结果表明,当HEA-MF质量分数为30%时,热稳定性能得到明显改进,起始分解温度达到290℃。HEA-MF醚化度为3.46时,其漆膜的综合性能最佳。涂膜的光泽、硬度、附着力均有明显提高,且气味小。     

Synthesis of novel acrylic modified water reducible alkyd resin: Investigation of acrylic copolymer ratio effect on film properties and thermal behaviors

New four‐component water reducible acrylic modified alkyd resins that are based on 1,3‐propanediol and contain different ratios of acrylic copolymer (AC) were synthesized by using a novel four‐stage fatty acid method. The final content of solids in the water reducible acrylic modified alkyd resins was 60% by weight. After the modified alkyd resin films were cured at 150°C for 1 h, it was observed that the use of AC as the modifier component had improved their physical and chemical surface coating properties and thermal behaviors. Experimental results show that the optimum AC ratio is 40% of the equivalent amount of AC to alkyd resin. Low‐volatile organic compounds (VOC) content water reducible acrylic modified alkyd resins yielded soft and flexible films with high chemical/thermal resistance, suitable for manufacturing of surface coating binders. POLYM. ENG. SCI., 56:947–954, 2016. © 2016 Society of Plastics Engineers     

A novel flame retardant UV‐curable vinyl ester resin monomer based on industrial dipentene: Preparation,characterization, and properties

A novel bio‐based and flame‐retardant UV‐curable vinyl ester resin (VER) monomer named Diglycidyl ester of maleinized dipentene modified with dibutyphosphate and methacrylic anhydride (MDDMD) was synthesized from industrial dipentene via Diels‐Alder reaction, glycidylation, epoxy ring‐opening reaction, and esterification. Its chemical structures were characterized by Fourier transform infrared (FTIR) analysis and proton nuclear magnetic resonance (¹H‐NMR). In order to improve its flexibility, we prepared a series of copolymers under UV light radiation by mixing it with certain proportions of poly(ethylene glycol) dimethacrylate‐200 (PEGDMA‐200) which contained flexible groups. Their tensile property, curing degrees (CD), hardness, limiting oxygen index (LOI), dynamic mechanical thermal properties, and thermostability were all investigated. The cured mixed resins have a relatively high tensile strength of 10.05 MPa and curing degrees up to 92.5%. Both hardness (range: 50 to 23 HD) and LOI (range: 22.8% to 24.4%) of cured resins are improved with the increase of MDDMD content. Dynamic mechanical analysis (DMA) shows that their glass transition temperatures rise with the increase of MDDMD content. Thermogravimetric analysis (TGA) shows that the thermal stability of cured resins is enhanced with the increase of PEGDMA‐200 content, as the main thermal initial decomposition temperatures are all above 260 °C and char yield at 800 °C are above 18.10%. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44084.     

Preparation of low refractive index fluorinated materials for antireflection coatings

Novel low refractive index fluorinated polymers were prepared from perfluoroalkylsilane and polyethoxysiloxane by a sol‐gel technique for antireflection applications. Perfluoroalkylsilane having low refractive index fluoroalkyl groups incorporate polyethoxysiloxane by condensation of their siloxane groups to improve the adhesion and hardness of the fluorinated polymers. Syntheses and characteristics of the fluorinated polymers were investigated by the studies of FTIR, GPC, UV–vis, ellipsometry, and mechanical tests. The experimental results reveal that the refractive index and hardness of the coating using the optimal fluorinated polymer were about 1.39 and 3H, respectively, which meet the requirements in practical applications. It was also found that the fluorinated polymer made from polyethoxysiloxane had a better hardness than that made from tetraethyl orthosilicate. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Perfluoropolyether polymers by UV curing: design,synthesis and characterization

Perfluoropolyether (PFPE) structures can be functionalized with acrylic groups using appropriate hydrogenated acrylic monomers: the macromers obtained are highly reactive under UV irradiation, and fluorinated polymers can be obtained. In the first part of this work is described the synthesis of new PFPE (meth)acrylic oligomers by extending OH‐terminated fluorinated chains with urethane groups and reactive acrylic functions. The photopolymerization reaction of each product is then reported followed by the characterisation of the main thermal, mechanical and surface properties of UV‐cured coatings. The polymers have good thermal resistance and fair mechanical and chemical resistance. More interestingly they show very low refractive index and low surface tension. For these latter properties the products can be advantageously used in highly demanding applications such as photonic devices and nano‐patterning. Copyright © 2011 Society of Chemical Industry     

Synthesis,thermal properties,and flame retardance of phosphorus‐containing epoxy‐silica hybrid resins

A novel epoxy resin modifier, phosphorus‐containing epoxide siloxane (DPS) with cyclic phosphorus groups in the Si O network, was prepared from the reaction of 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) with polyhedral‐oligomeric siloxanes, which was synthesized by the sol–gel reaction of 3‐glycidoxypropyltrimethoxysilane. DPS was confirmed by Fourier transform infrared and ²⁹Si NMR measurement, and then was employed to modify epoxy resin at various ratios, with 4,4‐diaminodiphenyl‐methane as a curing agent. In order to make a comparison, DOPO‐containing epoxy resins were also cured under the same conditions. The resulting organic–inorganic hybrid epoxy resins modified with DPS exhibited a high glass transition temperature (T_g), a good thermal stability, and a high limited oxygen index. In addition, the tensile strength of cured products was also rather desirable. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers     

Synthesis,characterization, and properties of silicone–epoxy resins

Silicone–epoxy (SiE) resins were synthesized through the hydrolytic condensation of 2‐(3,4‐epoxycyclohexylethyl) methyldiethoxysilane (EMDS) and the cohydrolytic condensation of EMDS with dimethyldiethoxysilane. Structural characterization was carried out by ¹H‐NMR, ²⁹Si‐NMR, and mass spectrometry analysis; the resins were linear oligomers bearing different numbers of pendant epoxy groups, and the average number of repeat Si O units ranged from 6 to 11. Methyhexahydrophthalic anhydride was used to cure the SiE resins to give glassy materials with high optical clarity. The cured SiE resins showed better thermal stability and higher thermal and UV resistances than a commercial light‐emitting diode package material (an epoxy resin named CEL‐2021P). The effect of the epoxy value on the thermal and mechanical properties and the thermal and UV aging performances of the cured SiE resins were investigated. The SiE resins became more flexible with decreasing epoxy value, and the resin with the moderate epoxy value had the highest thermal and UV resistances. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Solvolyse- und umesterungsreaktionen bei der vernetzung von alkyd- und acrylatharzen mit melaminvernetzern

One acrylic and different alkyd resins were cured with a melamin resin. Technical properties, swelling degrees, relativ IR-absorbances, and volatiles in the waste gas were determined quantitatively. From these data the amount of iso-butanol for the crosslinking and selfcondensation reactions can be calculated. In addition it was observed a solvolysis reaction of the alkyd resin and a transesterification reaction of the acrylic resin because of the reaction of the ester groups with the iso-butanol eliminated from melamine resin. Evidence is given for the solvolysis reaction by investigation of the specific cleavage products by means of IR, GPC, and GC/MS measurements. A pathway for the solvolysis reaction is proposed.     

Study of performance properties of itaconic acid based acrylic-modified polyester for industrial baking finishes

Itaconic acid based unsaturated polyesters have been synthesized followed by their co-polymerization with commonly used acrylic monomers. Series of such acrylic-modified polyesters have been prepared and examined their physical and performance characteristics. Apart from determining various physico-chemical characteristics, these resins were also characterized for their molecular weight distribution and grafting of acrylic on polyester using gel permeation chromatography (GPC) and FT-IR techniques respectively. The performance of cured film and the effect on cross-linking density of the synthesized acrylic-modified polyesters were investigated through dynamic mechanical analyzer (DMA) using melamine formaldehyde resin as a cross-linker at elevated temperature. The resultant polymeric film showed excellent hardness, flexibility, impact resistance, adhesion, and cupping with improved weathering resistance over non-acrylated polyester.     

环氧树脂/三羟甲基三聚氰胺硅化物固化体系阻燃性能与耐热性研究

利用三聚氰胺和甲醛合成了三羟甲基三聚氰胺（TMM）,将其与正硅酸乙酯(TEOS)反应得到三羟甲基化三聚氰胺硅化物（TMMSi）。将TMMSi与环氧树脂复合,采用4,4'-二氨基二苯基甲烷(DDM)作固化剂来制备环氧树脂/TMMSi固化物,并对固化物的热性能和阻燃性能进行了分析。结果表明,与环氧树脂/TMM固化物相比,环氧树脂/TMMSi固化物的玻璃化转变温度变化较小,高温耐热性提高不明显,但是阻燃性能得到了大幅度提高。当TMMSi含量为15份时,环氧树脂/TMMSi固化物的极限氧指数达到29.6 %,比纯环氧树脂固化物提高了40 %。     

Alkali catalysed curing of starch-melamine resin systems

Summary The curing process in starch adhesives modified with melamine resin can take place by co-condensation or self-condensation. A high degree of co-condensation is required to provide a good water resistance of a cured glue joint. This can be attained by using melamine resins with a high concentration of hydroxymethylamino groups. The reduced effect of the adhesive on storage is due to a degradation of the melamine resin through the elimination of formaldehyde.     

UV curable glycidyl carbamate based resins

The synthesis and characterization of UV curable resins based on glycidyl carbamate chemistry have been explored. Glycidyl carbamate (GC) functional resins have been used to obtain crosslinked coatings with a wide range of properties using several crosslinking techniques such as epoxy-amine, self-crosslinking, and sol-gel. GC resin technology was further expanded to UV curable coatings by reacting polyfunctional GC resins with acrylic acid to yield acrylated glycidyl carbamate (AGC) resins. Alcohol-modified UV curable GC resins were also prepared to obtain lower viscosity. Commonly used reactive diluents were used to prepare a UV curable GC coating formulations. The coatings were cured in air using a Fusion LC6B Benchtop Conveyer with an F300 UV lamp. The degree of conversion of acrylic double bonds during UV curing was determined using real time FTIR and showed that the resins had fast cure rates and high extents of conversion of acrylate groups. Coating properties such as hardness, impact strength, methyl ethyl ketone double rubs, flexibility, and adhesion were studied. Dynamic mechanical analysis was used to determine crosslink density of the coatings. Differential scanning calorimetry and thermogravimetric analysis were used to study the thermal properties of the coatings. The type of polyisocyanates and the extent of modification in GC resins influenced the degree of conversion, crosslink density, and coating performance.     

Synthesis,characterization, and performance evaluation of hard,anticorrosive coating materials derived from diglycidyl ether of bisphenol A acrylates and methacrylates

Diglycidyl ether of bisphenol A acrylate (DAC) and diglycidyl ether of bisphenol A methacrylate (DMAC) were synthesized by the reaction of an epoxy [diglycidyl ether of bisphenol A (DGEBA)] with acrylic acid and methacrylic acid, respectively. The synthesized resins were characterized by determination of the acid, hydroxyl, and saponification values. Structure elucidation was done by gel permeation chromatography, Fourier transform infrared spectroscopy, ¹H‐NMR spectroscopy, and ¹³C‐NMR spectroscopy. DACs were cured with melamine formaldehyde resin at low pH values. The pH of the resin systems was adjusted with phosphoric acid. The coatings of these systems were formed on mild steel specimens for physicomechanical and chemical/corrosion‐resistance performance. The coatings of DAC and DMAC showed excellent scratch hardness and good impact‐resistance performance. The coatings of DMAC showed better performance than DAC with respect to chemical and corrosion resistance. Thermogravimetric analysis and differential scanning calorimetry were used to investigate the thermal stability and curing behavior of these systems. DAC showed a little higher glass‐transition temperature than DMAC and also showed a higher thermal resistivity. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 494–501, 2005     

New melamine–formaldehyde–ketone resins. VI. Preparation of filled molding compositions and compression‐molding materials from reactive solvents based on cyclohexanone

The conditions and a method of preparing new molding compositions and filled compression‐molding materials from melamine–formaldehyde–cyclohexanone resins are described. The resins were obtained from melamine solutions in a reactive solvent prepared by the reaction of 1 mol of cyclohexanone with 7 mol of formaldehyde. The fillers were wood powder and sulfite cellulose. The thermal properties of the samples prepared from the compositions were studied with dynamic thermal analysis, thermogravimetry, and differential scanning calorimetry analysis. Selected mechanical properties [Brinell hardness, unnotched impact strength (Charpy method), and bending strength] of the cured resins were also measured. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Preparation and curing of alkyd based on ricinoleic acid/melamine coatings

Three alkyd resins of high hydroxyl numbers based on ricinoleic acid, phthalic anhydride and glycerin, trimethylolpropane or ethoxylated pentaerythritol as polyol were prepared. Afterwards synthesized alkyds were made into baking enamels by blending with commercial melamine-formaldehyde resins (weight ratio of 70:30 based on dried mass). Alkyd/melamine resin mixtures were cured in a differential scanning calorimeter (DSC) under non-isothermal mode. Apparent degree of curing as a function of temperature was calculated from the curing enthalpies. Fourier transform infrared spectroscopy (FTIR) was used to identify characteristic peaks of resin mixtures before and after being cured. The gel content, hardness, elasticity and impact resistance of coated film cured at 150 °C for 60 min were measured. The onset of film thermal degradation, determined by thermogravimetric analysis (TGA) was observed at the temperatures from 281 to 330 °C. Based on the results obtained we suppose that the combinations of synthesized alkyds based on ricinoleic acid with used melamine resins could be employed as the compositions for the preparation of baking enamels.     

光敏性氨基丙烯酸树脂的合成及其在光成像阻焊油墨中的应用研究

本文以β-丙烯酸羟乙酯为三聚氰胺甲醛树脂的醚化剂,进行醚化缩合反应合成了用于光成像阻焊油墨活性稀释剂氨基丙烯酸树脂(β-丙烯酸羟乙酯改性三聚氰胺甲醛树脂,HEA-MF)。用红外光谱分析了产物的主要基团,验证了2步的反应机理;用高压液相色谱仪(HPLC)分析了醚化产物的醚化度;合成的HEA-MF贮存性能良好,游离甲醛含量低。以β-丙烯酸羟乙酯改性三聚氰胺甲醛树脂为具有感光功能的活性稀释剂制备光成像阻焊油墨,用傅立叶实时红(FT-RTIR)对其光聚合性能进行了研究,用热失重分析仪(TGA)分析涂膜的耐热性能,用视频变焦显微镜分析了显影图形,考查了光引发剂浓度,HEA-MF含量和醚化度等因素的影响,结果表明,以HEA-MF为活性稀释剂制得的光成像阻焊油墨在保持良好的显影性的同时具有更好的光固化性能和热稳定性。     

Acrylic resins resisting oxygen inhibition during free‐radical photocuring. I. Formulation attributes

A resin system was found to be resistant to the formation of an oxygen‐inhibited layer when cured in air via conventional free‐radical photopolymerization. The resins, containing multifunctional acrylates and a high concentration of a photoinitiator, were applied as thin film coatings and photocured with either visible light (400–500 nm) or UV light (254 nm). Fourier transform infrared spectroscopy with an attenuated total reflection attachment and pencil hardness were used to assess the surface double‐bond conversion and the surface hardness of the coatings cured in air and without air, respectively. The surfaces of many tested resins could produce similar conversions under both curing conditions. Optimally formulated resins had a high conversion and hardness even when the irradiance was as low as 50 mW/cm² for the visible light and 4 mW/cm² for the UV light. The requirements for possessing such a unique curing property are presented. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

A Novel Type of Organo Clay Containing Alkyd-Melamine Formaldehyde Resins

In this study, organo clay-modified alkyd resins were synthesized and these modified alkyd resins were cured with different ratios of melamine formaldehyde resin for the first time. Alkyd resins were blended with 30% and 40% of a commercial melamine-formaldehyde resin. Alkyd-melamine formaldehyde resin films were cured at 140°C for 2 h in an oven. The effect of organo clay addition on the physical and chemical film properties was investigated. These surface coating properties of the resins enhanced with amount of organo clay up to 2–3%. These resins are suitable for manufacturing of high-performance industrial baking enamels.