A highly branched polythiourethane acrylate used for UV-curable high antireflection coatings

A series of highly branched polythiourethane acrylates (BPTUAs) were prepared through the double thiol-ene click reaction of thiol-endcapped difunctional thiourethane as an oligomer A₂ (Oligo-TU) with trimethylolpropane tri(thioglycolate ethylene glycol acrylate) (TMPTTA) as a trifunctional monomer B₃ in different ratios. The Oligo-TU was synthesized via the addition reactions of 2,4-toulene diisocyanate with 1,4-butanediol, and further with 4,4′-thiobisbenzenethiol. The TMPTTA was synthesized by the thiol-ene click reaction of trimethylolpropane tri(thioglycolate) (TMPTT) with an excess of ethylene glycol diacrylate. For comparison, a tetrafunctional thiourethane acrylate (TUA) was also synthesized. Finally, the obtained BPTUA and TUA were further modified with 2-mercaptobenzothiazole, 2-mercaptothiazoline and mercapto-5-methyl-thiadiazole, respectively, to form highly branched polyfunctional thiazole-based acrylates BPTUA-TAs and TUA-TAs. The molecular structures were confirmed by FT-IR and ¹H NMR analyses. The number average molecular weights and their polydispersity were determined by GPC spectroscopy. The UV irradiation using a medium pressure mercury lamp was applied to prepare the optical films in the presence of a photoinitiator. The refractive indices of UV-cured films were measured using a He-Ne laser at 632.8 nm. The results showed that both BPTUA and TUA films possess the similar refractive indices in the range of 1.592–1.604. However, the higher refractive indices in the range of 1.603–1.620 with BPTUA-TA films than 1.601–1.609 of TUA-TA films were obtained. All samples showed the high pencil hardness and impact resistance, as well good flexibility.     

Properties of UV-curable polyurethane acrylates for primary optical fiber coating

Studies have been made on the effects of the chemical structure of reactive urethane acrylate prepolymers and diluents (reactive monomers) and overall composition of the prepolymer/diluent on the properties of the UV-curable polyurethane acrylates for primary optical fiber coating. We prepared several urethane acrylate prepolymers from two different isocyanates, 4,4′-dicyclohexylmethane diisocyanate (HMDI) or isophorone diisocyanate (IPDI), and two different polyols, polybutadiene diol (PBD) or polypropylene oxide diol (PPG), and 2-hydroxyethyl acrylate (HEA) with dibutyl tin dilaurate as a photoinitiator. UV-curable coating materials were formulated from the prepolymers and 2,2-dimethyl 2-phenyl acetophenone as a photoinitiator with one of four different diluents such as 1-vinyl 2-pyrrolidone (VP), lauryl methacrylate (LMA), acrylic acid 2-ethyl hexyl ester (AEHE), and acrylic acid n-butyl ester (ABE). It was found that AEHE is the desirable diluent in the formulation of the primary fiber-coating material. The desirable composition of PBD, when mixed PBD/PPG diols are used, should be about 50 wt % for optimum formulation. Most of the urethane acrylate prepolymers prepared in this study could be applied in the formulation of primary optical fiber coating and exhibited good properties of buffer functions, including low glass transition temperature, low modulus even at low temperature, say, below ?40°C, high refractive index, and low viscosity. © 1992 John Wiley & Sons, Inc.     

Effects of the chirality and functionality of monomers on the holographic gratings formed in photosensitive films

Photosensitive holographic polymer films were fabricated. Instead of liquid crystals, a nonreactive high‐refractive‐index diphenyl sulfide was mixed with several monomers and an initiator for the preparation of the holographic grating films. To investigate the formation of periodic arrays of the photosensitive refractive‐index modulation films and the effects of the chirality and functionality of monomers on the diffraction efficiency, chiral monomeric (?)‐bornyl acrylate, (+)‐bornyl acrylate, and the racemate (±)‐bornyl acrylate were synthesized and copolymerized with various multifunctional monomers. A reasonable schematic of the photosensitive polymerization mechanism was proposed. The effects of the multifunctional monomers, initiator concentrations, and feed monomer concentrations on the diffraction efficiencies were investigated. The morphologies of the polymer matrices were studied with scanning electron microscopy. Pictures of real light diffraction patterns with 15 grating points were obtained. In comparison with those described in the literature, the diffraction efficiency obtained in this investigation was relatively high. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2246–2254, 2003     

Synthesis of novel UV-curable difunctional thiourethane methacrylate and studies on organic–inorganic nanocomposite hard coatings for high refractive index plastic lenses

This study relates to the development of ultraviolet (UV)-curable, organic–inorganic nanocomposite hard coatings for plastic lens substrates, especially for polythiourethane (PTU) and polycarbonate (PC). Novel difunctional thiourethane methacrylate (mercaptoethylsulfide-thiourethane methacrylate: coded MES-TUMA and isophorone diisocyanate-mercaptoethylsulfide-thiourethane methacrylate: coded IPDI-MES-TUMA) was synthesized to enhance the adhesive strength for PTU. On the basis of IR, ¹H NMR, electron spray ionisation-mass spectrometry (ESI-MS) analysis and gel permeation chromatography (GPC), the expected structures were confirmed. These difunctional thiourethane methacrylates were easily mixed with multifunctional urethane acrylate, surface-modified ZrO₂–TiO₂ nanoparticles and photoinitiator in coating formulations. The UV-cured organic–inorganic nanocomposites were very useful as hard coatings for high refractive index plastic lenses such as PTU and PC.     

无机型人造石表面紫外光固化涂膜研究

以KH-550为打底液对无机型人造石表面进行预处理,然后以紫外光固化涂料罩光.讨论了低聚物和活性稀释单体的组成、消泡剂种类和KH-550的用量对人造石表面紫外光固化涂膜性能的影响.结果表明,以质量分数为3%的KH-550对人造石表面进行预处理后,按低聚物55%,活性稀释单体40%,光引发剂和助剂分别为4%和1%的质量分...     

Synthesis and Characterization of UV-curable Hyperbranched Urethane Acrylate

The UV-curable hyperbranched urethane acrylate (HBUA) with a multi-hydroxyl functional hyperbranched polyester core was synthesized via a two-step procedure. The products were characterized by size exclusion chromatography, Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, and thermogravimetric analysis. The mechanical properties of UV-cured HBUA films were also investigated. The polydispersity index of HBUA is 2.31 and the endcapped degree of acrylation is 79.8%. The viscosity of HBUA is relatively low in favor of mixing and spreading. The UV-cured films exhibit high hardness and good flexibility.     

Hyperbranched polysiloxane-modified UV-curable graphene conductive coatings: preparation and characterization

A new UV-curable hyperbranched silicone epoxy acrylate resin was synthesized, and two kinds of carbon-based components, graphite and graphene, were applied as conductive materials. An ultraviolet-curing coating was successfully synthesized with using epoxy acrylate (EA) as oligomer, butyl acrylate (BA), and hyperbranched polysiloxane (HPSi) as monomers, benzoin dimethyl ether (DMPA), and benzophenone (BP) as photo-initiators, triethanolamine (TEA) as photo-activator, and other auxiliaries. In this work, the UV-curing efficiency and cured performance, together with the effect of different conductive fillers and the amount of conductive filler on the integrated performance of the composites, are investigated. The results show that as the HPSi content increases, the curing time is shortened. At the addition amount of 7.5%, it reaches the best conductivity, and at the addition amount of 10%, the corrosion resistance after curing is the best. However, the maximum tensile strength of 10.4% is obtained at 0.75 graphene. The FE-SEM micrographs of the UV-curable conductive coating show that with increasing incorporation of graphene into the substrate, the fractured surface of a rough surface changes to smooth one. Thermal properties of the films investigated using TGA curves indicate that graphene-doped conductive adhesive film (315.1 °C) possesses much higher heat resistance than that of graphite-doped conductive adhesive film.     

Refractive index tuning of highly transparent bismuth containing polymer composites

A new method for the preparation of transparent bismuth containing composites is reported. With the organic ligands 2,3-Dihydroxypropylmethacrylate (HMA) and 2-(Methacryloyloxy)-ethylacetoacetate (AcMA), bifunctional monomers with a functional group for metal complexation on the one hand and a reactive group for polymerization on the other hand were found. By integrating up to 20 wt-% bismuth in the monomer mixtures, an increase of the refractive index of 4.0% (?n = 0.058) is determined. The metal complexation was observed via infrared spectroscopy (AcMA) and NMR spectroscopy (HMA). Subsequent addition of trimethylolpropane triacrylate (TMPTA) as cross-linking agent and 2,4,6-trimethyl-benzoyldiphenylphosphine oxide (TPO) as photoinitiator to the bismuth containing monomers Bi-HMA and Bi-AcMA lead to a UV-curable liquid. Photoinduced polymerization was used to generate transparent bismuth containing hybrid materials with increased refractive index. The polymers were characterized by UV/VIS spectroscopy, ellipsometry and DTA/TG. The materials show a high transmission (>80% in 2 mm thick plates) in the visible spectral range, and an increased refractive index with increasing bismuth content.     

含氟硅丙烯酸酯核壳乳液及涂膜表面性能

在可聚合阴离子乳化剂体系下,以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)为主要单体,甲基丙烯酸十二氟庚酯(DFMA)、γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)为功能单体,采用半连续种子乳液聚合法合成了含氟硅丙烯酸酯核壳乳液。考察了DFMA和KH-570用量对乳液聚合过程和乳胶膜表面疏水性能的影响,并对乳胶膜的表面自由能进行了估算。采用傅里叶红外光谱(FT-IR)、差示扫描量热仪(DSC)、热重(TG)、接触角(CA)及X射线光电子能谱(XPS)对氟硅丙乳液及乳胶膜进行了表征。研究结果表明,氟硅单体有效地参与了聚合,乳胶膜中氟硅元素呈梯度分布,当氟硅丙乳液中DFMA和KH-570用量分别为16%和5%（质量分数）时,涂膜-空气界面与去离子水的接触角为110.6°,涂膜的表面能低至15.4 mN·m^-1,其疏水性和耐热性有较大幅度提高。     

光聚合型聚硅氧烷改性聚醚聚氨酯丙烯酸酯低聚物的合成、表征与性能

以羟烷基聚硅氧烷(Q4-3667)、聚丙二醇(PPG-2000)、异佛尔酮二异氰酸酯(IPDI)、二乙醇胺和丙烯酸β-羟乙酯(HEA)为原料合成了一种光聚合型有机硅改性聚醚聚氨酯丙烯酸酯低聚物(Si~5E~5PUA),并用傅里叶红外光谱(FTIR)、核磁共振氢谱(1HNMR)、核磁共振硅谱(29SiNMR)和凝胶渗透色谱(GPC)对其结构进行了表征。详细研究了Si~5E~5PUA与不同单体配比体系的黏度、光聚合性能、聚合过程的体积收缩及其固化膜的玻璃化转变温度。结果表明,Si~5E~5PUA与丙烯酸酯单体具有良好的相容性;其体系具有优异的光聚合性能,最终双键转化率达90%以上,单体官能度的增加可以提高固化膜的玻璃化转变温度,Si~5E~5PUA体系的体积收缩在3.3%~5.6%。     

High-performance waterborne UV-curable polyurethane dispersion based on thiol–acrylate/thiol–epoxy hybrid networks

Synthesis, characterization, and film performance of waterborne thiol–acrylate/thiol–epoxy hybrid coatings are highlighted in this article. A dimer acid-modified epoxy (DME) polyol, containing both hydroxyl and epoxy functional groups, was prepared by reacting epoxy resin (EEW = 190 g/equi) with dimer fatty acid at 2:1 molar ratio. Further, a base UV-curable polyurethane acrylate dispersion (UV-PUD), with a pendant epoxy functional group, was prepared by reacting polyol (DME), isophorone diisocyanate, and dimethylol propionic acid and end-capped with hydroxyethyl methacrylate with subsequent dispersion in water. Prepared intermediates were characterized for the parameters relevant to the study by physical, spectroscopic, and chemical methods. UV-curable thiol–acrylate/thiol–epoxy hybrid coatings were prepared by blending UV-PUD with trimethylolpropane tris(3-mercaptopropionate) (TMPMP) at four different thiol ratios (0, 0.3, 0.6, and 1.0) with respect to acrylate/epoxy groups. Cured films of the hybrid coating were identified by FTIR spectroscopy. The impact of thiol ratio on film performance was evaluated in terms of mechanical, chemical, thermal, and coating properties. The gel content measurements confirm that the addition of TMPMP increased the double bond conversion along with the epoxy group. Evaluation of cured samples shows the significant improvement in storage modulus, glass transition temperature, tensile strength, and hardness with increase in thiol ratio. The cured films possessed excellent water and acid resistance (<4%) even after 28 days of immersion. Moreover, the notable improvement was alkali resistance of cured films, i.e., as thiol ratio was increased from 0 to 1, weight loss in alkaline environment deceased from 49.5 to 4.5% after 28 days. Better properties of the thiol–acrylate/thiol–epoxy hybrid films will allow it as a potential application in low-volatile high-performance coatings.     

紫外光固化环氧丙烯酸酯涂料的制备及耐蚀性能研究

以E-51环氧树脂和丙烯酸为原料合成出光敏性环氧丙烯酸酯低聚物,制备了不同组成的紫外光固化涂料.合成产物的红外光谱分析结果表明,光敏性碳碳双键基团被引入到环氧树脂结构中;固化后涂层的红外表征结果表明,碳碳双键C=C的特征吸收峰消失,涂层固化较完全.在无水乙醇、5%NaOH和5%H2SO4溶液中的浸泡实验以及在3.5%NaCl溶液中的电化学阻抗谱测量结果表明,涂层具有较好的耐蚀性,其耐蚀性随着涂料中环氧丙烯酸酯含量的增加,呈先提高后下降的趋势.当环氧丙烯酸酯含量为40%,二缩三丙二醇双丙烯酸酯含量为50%时,所得涂层的耐蚀性最佳.     

The synthesis of hyperbranched poly (amine-ester) and study on the properties of its UV-curing film

Firstly, the monomer of N, N-diethylol-3-amine methylpropionate was obtained via Michael addition of methyl acrylate and diethanolamine. Then the hyperbranched poly (amine-ester) (HBPE) was synthesized through pentaerythritol as core molecules and monomer as AB₂. HBPE was characterized by Fourier transform-infrared spectroscopy, hydrogen nuclear magnetic resonance (¹H-NMR) and elemental analysis. Methyl tetrahydrophthalic anhydride (MTHPA) is grafted to the hydroxyl groups of HBPE and then glycidyl methacrylate (GMA) is introduced to the structure of HBPE, which is obtained by the UV-curable hyperbranched prepolymer (HBPE-MTHPA-GMA). Ultraviolet-differential scanning calorimeter showed that the HBPE-MTHPA-GMA has high photocuring speed under photoinitiator. Furthermore, the films also show good impact strength, outstanding adhesive force and primary thermal stability.     

UV固化低折射率光纤涂料的研制

研制的紫外光固化低折射率光纤类涂料由乙烯基聚硅氧烷、巯基聚硅氧烷、丙烯酸氟硅聚合物、光引发剂及助剂等组成。该涂料折射率小于1.40,固化速率小于0.3 s,吸水率低,拉伸强度为1.58MPa,伸长率为163%,适用温度范围为-60～200℃,可用于双包层石英光纤的外层以及光固化电连接器等方面。     

Preparation and characterization of self-crosslinking fluorinated polyacrylate latexes and their pressure sensitive adhesive applications

Self-crosslinking fluorinated polyacrylate latexes based on butyl acrylate (BA), fluorine monomer octafluoropentyl methacrylate (OFPMA), self-crosslinking functional monomers acrylic acid (AA) and 2-hydroxyethyl acrylate (HEA) were synthesized by a monomer-starved seeded semi-continuous emulsion polymerization process. The latexes and their corresponding films were characterized by laser particle size analyser, Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), contact angle goniometer, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Results indicated that the particle size of the latexes and the gel content of the films were both independent of the amount of OFPMA employed. On the other hand, the particle size of the latexes decreased and the gel content of the films increased with the incorporation of AA and HEA as expected. Glass transition temperature (T_g) and the thermal stability of the copolymer were both improved gradually as OFPMA content increased. XPS, AFM and water contact angle measurement indicated that the fluoroalkyl groups had a tendency to enrich on the surface of the films. However, this enrichment of fluorine on the film surface was reduced after the introduction of self-crosslinking functional monomers into the system. Finally, the adhesive property of the latexes was evaluated for application as a pressure sensitive adhesive (PSA).     

Ultraviolet curing of liquid polysulfide thiourethane acrylate

A series of liquid polysulfide thiourethane acrylate prepolymers were synthesized by the reaction of liquid polysulfide with isocyanate and hydroxyethyl acrylate. With and without a combination of acrylic monomers, the prepolymers were cured with ultraviolet radiation. The films exhibited a higher soft‐segment glass‐transition temperature than metal oxide cured polysulfide. With the addition of a diluent, the tensile strength and modulus increased, whereas the ultimate elongation decreased. The polysulfide backbone, combined with the crosslink generated from the photopolymerization of acrylic, produced films with superior oil resistance. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2358–2363, 2004     

新型UV固化P／Si协同阻燃EA涂层的制备与性能研究

为了提高uv固化环氧丙烯酸酯（EA）涂层的阻燃性能,并保持其良好的力学及光学性能,将丙烯酸羟乙酯（HEA）分别与KH-5707LPzOs反应合成新型含Si／P功能单体,并将其掺杂于EA中,制备了uV固化新型含P／Si协同阻燃EA透明涂层。利用红外光谱仪、紫外／可见光谱仪、热重及涂层力学测试仪等研究了涂层的性能。     

Boron-containing UV-curable oligomer-based linseed oil as flame-retardant coatings: synthesis and characterization

A boron-containing UV-curable oligomer was derived from linseed oil, phenylboronic acid and glycidyl methacrylate to use in flame-retardant coating applications. The synthesized UV-curable oligomer was characterized for its structural and physicochemical properties by means of Fourier transform infrared (FTIR), ¹H and ¹¹B-nuclear magnetic resonance (NMR) spectroscopy techniques. The boron-containing UV-curable oligomer (BELO) was added to a conventional polyurethane acrylate (PUA) at varying concentrations ranging from 10 to 40 wt% in the presence of a photoinitiator and a reactive diluent. LOI and UL-94 tests were performed to understand the flame-retardancy behavior of the synthesized BELO oligomer, and the results revealed that the flame retardancy of UV-curable coatings enhanced as the percentage of BELO oligomer in the coating formulations increased. The glass transition temperature (T_g) and thermal stability of cured coatings were analyzed by differential scanning calorimetry and thermogravimetric analysis, respectively. The TGA analysis showed that char yield at 600 °C increased by increasing the BELO oligomer content. The mechanical properties, and stain, solvent, and chemical resistance and thermal behavior of the coatings were investigated. Incorporation of BELO into the PUA coating formulations and the comparison of the properties of BELO-incorporated PUA coatings with those of the conventional PUA coating exhibited interesting results.     

高生物基含量光固化涂料的制备及其性能研究

环氧化大豆油丙烯酸酯(AESO)已大规模用于UV固化涂料中,但目前同时获得高生物基含量以及优异机械性能的大豆油基光固化涂料依然是一个很大的挑战。文中设计并合成了异山梨醇甲基丙烯酸酯(ISDMA)作为光固化活性稀释剂。使用流变仪研究了ISDMA对AESO稀释性的影响。将ISDMA与AESO混合制备了一系列生物基UV固化涂料,并对这些涂料的热机械性能、力学性能和涂层基本性能进行了评估。结果表明:ISDMA对AESO表现出良好稀释性的同时,可以有效地提高固化涂层的玻璃化转变温度(T_g)、储能模量和硬度。     

UV-curing behavior and properties of tri/di(acryloyloxyethyloxy) phenyl silane used for flame-retardant coatings

The silicon-containing multifunctional acrylates, tri(acryloyloxyethyloxy) phenyl silane (TAEPS) and di(acryloyloxyethyloxy) methyl phenyl silane (DAEMPS) were prepared by using the transetherification of phenyltrimethoxyl silane and dimethoxymethylphenyl silane with 2-hydroxylacrylate, respectively. The molecular structures were confirmed by FTIR, ¹H NMR, ¹³C NMR and ²⁹Si NMR spectroscopic analysis. The obtained TAEPS and DAEMPS as tri- and difunctional monomers were blended with a commercial oligomer epoxy acrylate (EB600) in different ratios to formulate a series of silicon-containing UV-curable resins. The viscosity of the resins reduced obviously while the photopolymerization rates according to the photo-DSC analysis greatly increased by the addition of monomers. The thermal degradation and flame-retardant behaviors of the cured films were evaluated by the thermogravimetric analysis and the limiting oxygen index (LOI) measurements, respectively. The char yields measured under air atmospheres increased extraordinarily with increasing the silicon content. The LOI values increased from 21 for EB600 to over 30 at 70 wt% monomer loading, demonstrating that the improved flame retardancy was obtained. The data from dynamic mechanical thermal analysis showed that TAEPS and DAEMPS have good miscibility with EB600. The crosslink density of UV-cured EB600/TAEPS film showed a greater increase along with the monomer content, compared with that of EB600/DAEMPS. The mechanical property measurement indicated that the addition of TAEPS led to an increase in elongation-at-break and a first increase and then decrease in tensile strength.