脂环族环氧树脂的紫外光固化性能

研究了脂环族环氧树脂CER-170的紫外光固化性能,利用红外光谱对树脂固化前后的结构进行了表征,考查了光固化时间对凝胶率的影响,并对在最佳固化条件下所得的固化产物进行了性能测试。结果表明,在光固化时间为6min时,凝胶率已达80.90％。在此条件下得到的胶膜冲击强度为4．9N·m;柔韧性为2mm,硬度为3H．粘附力为3级。     

混杂紫外光固化研究进展

综述了近年国内外混杂紫外光固化研究的进展和应用情况。其中包括丙烯酸酯-环氧树脂体系、丙烯酸酯-乙烯基醚体系的自由基-阳离子混杂光固化,自由基-自由基体系混杂固化,光-热、光-空气及光-潮气混杂固化等。这些混杂固化方式使固化产物的综合性能更为优异。     

有机硅纳米杂化改性环氧胶的研制和应用

通过溶胶-凝胶法制备了纳米有机硅溶胶。用透射电镜和红外光谱表征和分析了纳米粒子的形态和粒径,粒径为30－70nm。制备了用活性稀释剂糠醛和丙酮及有机硅纳米杂化改性的环氧胶。研究了胶液的初始黏度、渗透性、力学强度、弹性模量、粘接性、表面疏水性和防腐蚀性能。实验结果表明,环氧树脂含量、有机硅溶胶、硅烷偶联剂等对改性环氧胶的这些性能有显著影响,改性环氧胶双组分混合液的初始黏度可低至1.1mPa·s,渗透性强,固结体抗压强度高达40．8－81．5MPa,弹性模量为1．3－2．1×10^3MPa,剪切粘接强度5．1－11．9MPa,防水抗渗性及防腐蚀耐候性良好,可应用于灌浆防水加固补强、工业地坪涂料和防腐蚀涂料等多种用途。     

Ultraviolet‐curing behavior of an epoxy acrylate resin system

Ultraviolet (UV)‐curing behavior of an epoxy acrylate resin system comprising an epoxy acrylate oligomer, a reactive diluent, and a photoinitiator was investigated by Fourier transform infrared (FTIR) spectroscopy. The conversion changes of the resin system containing 20 phr of 1,6‐hexanediol diacrylate as a reactive diluent and 2‐hydroxy‐2‐methyl‐1‐phenyl‐propan‐1‐one as a photoinitiator were measured under different UV‐curing conditions. The fractional conversion was calculated from the area of the absorption peak for the vinyl group vibration occurring at 810 cm^?1. The effects of photoinitiator concentration, total UV dosage, one‐step or stepwise UV irradiation, UV intensity, atmosphere, and temperature on the curing behavior of the resin system were investigated. The conversion of the resin system increased rapidly at the initial stage of the UV‐curing process but increased very slowly after that. The final conversion of the resin system was mainly affected by total UV dosage. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1180–1185, 2005     

Cationic UV‐curing of epoxidized cardanol derivatives

This paper demonstrates the high reactivity and potentiality of bio‐renewably obtained cardanol‐based epoxy monomers as well as the possibility of tuning the final thermomechanical properties by changing either the epoxy content or the chemical structure of the starting photocurable resin. The reactivity of the cardanol monomers towards the cationic UV‐curing process was investigated by Fourier transform IR analysis and it was shown that a high epoxy group conversion was achieved. Furthermore, the thermomechanical properties were investigated on crosslinked films by means of DSC and dynamic thermomechanical analysis. © 2020 Society of Chemical Industry     

UV固化水性环氧树脂的合成研究

对紫外光固化水性环氧树脂的合成工艺进行了研究,讨论了反应温度、反应时间、催化剂种类和用量,阻聚剂、羧基含量及固含量、中和剂等对水性环氧丙烯酸酯的合成和性能的影响。结果表明,合成环氧丙烯酸酯的最佳反应温度110℃,环氧丙烯酸酯与马来酸酐的最佳反应反应温度为80℃。反应时间均为5 h,三乙胺作催化剂,用量为反应物总质量的0.5%,对羟基苯甲醚作阻聚剂。实验表明,提出的紫外光固化水性环氧树脂的合成工艺可行,合成树脂具有水性特征,性能指标可以满足应用要求。     

紫外光固化环氧丙烯酸酯涂料的表征

研制了一种用于艺术玻璃彩绘的新型涂料——紫外线固化环氧丙烯酸酯涂料，主要通过涂膜硬度的测定、红外光谱(FTIR)和差示扫描量热分析法(DSC)研究了涂膜固化程度与辐射时间之间的关系，并用紫外光谱和红外光谱研究了引发剂及其引发涂膜固化的机理。     

Preparation and characterization of hybrid thiol‐ene/epoxy UV–thermal dual‐cured systems

Hybrid thiol‐ene/epoxy coatings were prepared by combining thiol‐ene photo‐curable formulations with epoxy monomers, through a dual UV–thermal curing process. An increase in glass transition temperature and in storage modulus was observed for the hybrid thiol‐ene/epoxy coatings when compared with the pristine thiol‐ene UV‐cured system. Also, the bisphenol A moieties introduced into the hybrid networks during the dual‐curing process induced an increase in thermal stability of the cured materials. It has been demonstrated that the addition of epoxy monomer to the thiol‐ene photo‐curable system is a good strategy to follow in order to improve the final properties of thiol‐ene‐based coatings leading to a wide range of possible applications for the hybrid materials. Copyright © 2010 Society of Chemical Industry     

Synthesis of a liquid zirconium hybrid resin and the ability of the resin to accelerate the curing of a transparent silicone‐modified cycloaliphatic epoxy nanocomposite

A liquid zirconium hybrid resin (Zr–QR) was synthesized through sol‐gel reactions of zirconium butoxide with silanol‐terminated polydimethylsiloxane (DMS‐S12) and γ‐glycidoxypropyltrimethoxysilane (Z‐6040). The sol‐gel reactions were monitored using Fourier transform infrared (FTIR) spectroscopy and proton nuclear magnetic resonance spectroscopy. The Zr–QR morphology was investigated using field emission transmission electron microscopy. The Zr–QR had a well‐ordered morphology and the dimensions were less than 5 nm. These properties were achieved because DMS‐S12 was used to separate the zirconium clusters and Z‐6040 was used to stabilize the Zr–QR. The acceleration of the curing reaction between silicone‐modified cycloaliphatic epoxy (SEP) and methylhexahydrophthalic anhydride (MHHPA) caused by the Zr–QR was investigated. Differential scanning calorimetry and FTIR spectroscopy investigations showed that the Zr–QR first reacted with MHHPA, producing chelating ligands and carboxylic acid. Unlike in the conventional method (adding acetic acid to cause non‐reactive chelating ligands to form), the carboxylic acid produced effectively accelerated the curing reaction between the SEP and MHHPA. The chelating ligand produced from the Zr–QR and MHHPA suppressed the gelation of the Zr–QR itself during the nanocomposite (SEP–Zr–QR) curing process. The cured SEP–Zr–QR nanocomposite exhibited excellent optical transmittance at visible wavelengths.© 2015 Society of Chemical Industry     

埃洛石固载铂催化合成硅骨架环氧树脂

以天然纳米管状埃洛石为载体,负载氯铂酸制得埃洛石固载铂催化剂,催化1,1,3,3-四甲基二硅氧烷和甲基丙烯酸缩水甘油酯的硅氢加成反应,合成一种硅骨架环氧树脂,产率达到93.26%。利用SEM和TEM表征了埃洛石固载铂催化剂的形貌。结果显示,纯化后的埃洛石呈纳米管状结构,管长为0.5~1.5μm,管外径为50~190nm,管内径为10~20nm,管体清晰,表面干净规整,固载铂催化剂后,催化剂颗粒在埃洛石表面均匀分布。利用红外光谱和氢核磁共振谱对硅骨架环氧树脂结构进行了表征。     

Study of cationic ring‐opening photopolymerizations using optical pyrometry

Studies of the photoinitiated cationic ring‐opening polymerizations of epoxide and oxetane monomers were conducted using optical pyrometry. Using this technique, the temperature of these photopolymerizations was monitored as a function of time. The effects of photoinitiator type and monomer structure on the rates of photopolymerization were investigated. Optical pyrometry was also used to investigate the acceleration of the photopolymerizations of various epoxide and oxetane monomers. Certain mixtures of monomers displayed synergistic effects that markedly increased their overall rates of polymerizations. In all cases in which acceleration of polymerization rate was noted, it could be attributed to an increase in the speed of ring opening of the initially formed protonated cyclic ether. The effects of relative humidity on the rate of cationic ring‐opening photopolymerizations of cyclic ether monomers were also investigated. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3303–3319, 2004     

Film performance and UV curing of epoxy acrylate resins

Radiation curing technology has encountered increased applications in recent years. The Asian geographical vicinity has and will be an expensive territory for years to succeed. There has been heightened governmental obligation to progress towards diminishing solvent practice to preserve the environment.

In the present study, the novolac as well as bisphenol-A based epoxy acrylates (or vinyl ester resins, VERs) were synthesised and extent of reaction and polymerisation was studied. It was observed that the above prepared oligomer when used with monofunctional/polyfunctional diluents can be cured in seconds time. Evaluation of film performance was also carried out.     

混杂聚合有机硅改性环氧丙烯酸酯的研究

利用4,4'二苯基甲烷二异氰酸酯(MDI)与双羟基聚甲基苯基硅氧烷分子中的羟基反应制得-Nco封端的预聚体,再将该预聚体与环氧丙烯酸酯(EA)混合,得到有机硅化学改性环氧丙烯酸酯.在此基础上,以氨基树脂为固化剂,制得常温固化涂层;以2-羟基-2-甲基-l-苯基-l-丙酮(即1103)为光引发剂,在紫外光照射下制得常温光固化涂层;以氨基树脂为固化剂,1103为光引发剂,在紫外光照射下制得常温混杂聚合涂层.讨论了上述3种涂层的硬度随固化时间的变化,用热重一差热分析(TG-DTA)技术研究了三者的耐温性.结果表明:常温混杂聚合涂层的硬度随时间的延长增加得最快,光固化涂层次之,常温固化涂层最慢.3种涂层都能耐420℃左右的温度.     

Fabrication of High‐Performance Cationic UV Curable Cycloaliphatic Epoxy/Silicone Hybrid Coatings

A series of cycloaliphatic epoxy acrylate prepolymer poly (METHB‐co‐MMA‐co‐BA) (MMB) and an epoxycyclohexyl‐modified polydimethylsiloxane (PDMS‐VCH) are prepared to fabricate hybrid coatings. The curing process, surface performance, mechanical properties, and thermal behavior are investigated by real‐time Fourier transform infrared (FT‐IR), contact angle measurements, tensile test, thermogravimetric analyzer (TGA), and differential scanning calorimeter (DSC). For the same photoinitiator (PI) concentration, both the epoxy value and the amount of PDMS‐VCH negatively affect the UV‐curing process. The contact angle of hybrid coatings increases by almost 12° with 4 wt% PDMS‐VCH's addition. The increasing ratio of soft acrylate segment can strengthen the toughness of materials markedly. Besides, thermal stability is enhanced with the increasing of epoxy value, while slight changes are found with the addition of PDMS‐VCH. Based on these properties, the hybrid coatings can be applied in various fields, including protection, decoration, and other displayed fields.     

Bicyclo‐orthoester as a low‐shrinkage additive in cationic UV curing

A commercially available bicyclo‐orthoester (BOE) was used as low‐shrinkage additive for cationic UV curing of epoxy resins. A high reactivity of BOE by ring‐opening homopolymerization has been observed under cationic UV curing conditions. The BOE and trimethylolpropane triglycidyl ether monomers are compatible and give rise to a cured copolymeric network, under UV irradiation, with a flexibilization increase by increasing the BOE content in the photocurable formulation. Shrinkage after photopolymerization shows a linear reduction by increasing the BOE content in the photocurable formulation; a volume expansion upon polymerization is reached in the presence of 50 wt% of the additive. Copyright © 2007 Society of Chemical Industry     

Hybridization of aqueous PU/epoxy resin via a dual self‐curing process

Amino‐terminated and carboxyl‐containing polyurethane (PU) is prepared by an isocyanate‐terminated PU prepolymer process. Carboxyl‐containing epoxy resin is obtained from a half‐esterification of epoxy resin with maleic anhydride. These two aqueous resins are obtained after neutralization with triethylamine and dispersion into water phase, respectively. A latent curing agent (TMPTA‐AZ) is prepared by a Michael addition of aziridine with trimethylolpropane triacrylate (TMPTA). A self‐curing system of PU/epoxy hybrid is obtained from a blending of these two aqueous resins with latent curing agent. PU/epoxy hybrid is derived from two self‐curing reactions on drying. The first curing for hybridization between PU amino groups with oxirane groups of epoxy resin is via a ring‐opening reaction and the secondary curing takes place on carboxyl groups of PU/epoxy hybrid with aziridine of TMPTA‐AZ. The final properties of these dual self‐cured PU/epoxy hybrids are reported. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Cationic UV curing behavior and thermal properties of oxetane‐modified polysiloxane prepared from tetraethyl orthosilicate

The oxetane‐modified polysiloxane (Oxe‐PSiO) was synthesized via the partial hydrolysis/condensation of tetraethyl orthosilicate (TEOS) and then transesterification reaction with 3‐ethyl‐3‐(hydroxymethyl)oxetane (EHO), and characterized by FT‐IR, ¹H NMR, ¹³C NMR, and ²⁹Si NMR spectroscopy. Using the water/TEOS molar ratios of 0.8–1.2, the number‐average molecular weights and polydispersity indices were obtained by GPC to range from 1.013 to 2.716 g mol^?1 and around 2.0, respectively. The viscosity of Oxe‐PSiO prepared from the water/TEOS molar ratio of 1.2 sharply increased to 177,545 cps from 438 cps of that from the molar ratio of 0.8. A series of cationic UV‐curable formulations were prepared by blending the Oxe‐PSiO synthesized with the water/TEOS molar ratio of 1.0 into an commercial oxetane‐based resin, 3,3′‐[oxydi(methylene)]bis(3‐ethyloxetane), in different weight ratios. The photopolymerization kinetics studied by photo‐DSC in the presence of triphenylsulphonium hexafluoroantimonate as a cationic photoinitiator showed that both the maximum photopolymerization rate and final oxetane conversion in the cured film decreased with increasing Oxe‐PSiO loading mainly due to the sharp increase in viscosity. The DMTA and DSC results both indicated the improvement in thermal stability, showing 12 and 13.4°C, respectively, higher T_g for the cured film with 50 wt % Oxe‐PSiO loading compared with the pure polymer. Moreover, the temperatures (T_10% and T_50%) at the weight loss of 10 and 50% and final char yields measured by TGA increased with increasing Oxe‐PSiO content. After adding 50 wt % Oxe‐PSiO, compared with the pure polymer the T_10% increased from 349 to 361°C, while the T_50% increased from 409 to 424°C, and with a char yield increase of 8.2% at 800°C. In addition, its greatly increased crosslinking density due to the formation of silica network resulted in the enhancement in pencil hardness from B of the pure polymer to 2H grade. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

超支化环氧／双酚A环氧树脂杂化材料的性能研究

以超支化环氧树脂HTDE-2改性HTDE-2／双酚A型环氧树脂杂化材料的粘接性能和胶膜性能,探讨了HTDE-2的含量对杂化材料的剪切强度、剥离强度、铅笔硬度和耐磨性的影响。研究表明,随着超支化环氧树脂含量的增加,杂化材料的剪切强度、剥离强度、铅笔硬度和耐磨性先增加后下降,在HTDE-2用量为4％左右时具有最大值,综合性能最好。     

Synthesis and properties of optically clear silicone resin/epoxy resin hybrids

Optically clear silicone/epoxy hybrid resins were synthesized. The silicone resin (SiR) carrying Si? H, Si? CH?CH₂ and Si? OH groups was prepared by hydrolytic condensation. The blends of SiR and diglycidyl ether of hydrogenated bisphenol A (DGEHBA) were cured through platinum‐catalyzed hydrosilylation and aluminium acetylacetonate‐catalyzed polymerization. The curing process was studied using differential scanning calorimetry and rigid‐body pendulum rheometry. It was found that the ratio of SiR to DGEHBA plays a major role in the curing process. The Si? OH groups of SiR assist polymerization of DGEHBA, and react with the epoxy resin to prevent phase separation. The cured hybrid resins are single‐phase materials with a transmittance of about 87% at 400 nm for a thickness of 3 mm using air as reference. UV resistance and thermal stability of the hybrids are largely dependent on the composition. The adhesive strength of the SiRs can be significantly improved by a small fraction of DGEHBA, with a marginal influence on UV resistance. However, increasing the epoxy proportion has a marked negative influence on thermal stability. Compounding stabilizers, especially thermal stabilizers, are essential, in particular for high epoxy content, if the hybrids are to be used for high‐brightness light‐emitting diode packaging. Copyright © 2011 Society of Chemical Industry     

Interaction of toughening mechanisms in a hybrid epoxy system

Interaction between different toughening mechanisms is studied using a heat treated hybrid system, consisting of carboxyl‐terminated butadiene acrylonitrile (CTBN) rubber and EXPANCEL (expandable hollow microspheres) as modifiers for an epoxy resin. It was found that the fracture toughness of the hybrid system is higher than that of either individually EXPANCEL‐ or CTBN‐modified system for a given content of modifier, although the maximum toughness was not substantially high compared with maxima of single modifier systems. Microscopic examination revealed that damage zone due to CTBN particles ahead of the crack reduces due to the presence of EXPANCEL particles and nevertheless its fracture toughness increased. A possibility was deduced that the cavitation due to CTBN assists with promoting compressive stresses around EXPANCEL particles ahead of the crack tip, resulting in increase in fracture toughness. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4470–4475, 2006