UV-光固化光纤涂料的研制

本文采用环氧丙烯酸酯与聚氨酯丙烯酸酯共混聚合的方法制备出新型的UV-光固化光纤涂料,其主要性能较好.研究了基体组成、引发剂、稀释剂以及固化工艺对UV-固化光纤涂料的光固化速度的影响.通过实验发现,环氧丙烯酸酯与聚氨酯丙烯酸酯的配比为 4:6～6:4、稀释剂的含量不大于20%时固化速度较快、性能较好,同时固化时灯距与固化膜厚度对固化速度的影响较大.     

Novel biobased photo‐crosslinked polymer networks prepared from vegetable oil and 2,5‐furan diacrylate

Novel biobased crosslinked polymer networks were prepared from vegetable oil with 2,5‐furan diacrylate as a difunctional stiffener through UV photopolymerization, and the mechanical properties of the resulting films were evaluated. The vegetable oil raw materials used were acrylated epoxidized soybean oil (AESO), acrylated castor oil (ACO), and acrylated 7,10‐dihydroxy‐8(E)‐octadecenoic acid (ADOD). 2,5‐Furan dicarboxylic acid (FDCA), which can be synthesized through the oxidative dehydration of C6 sugars, was identified by the US Department of Energy as one of 12 priority chemicals for establishing the green chemistry industry of the future. 2,5‐Furan dimethanol (bis‐hydroxymethylfuran), which can be derived from FDCA, was used as a starting material to synthesize 2,5‐furan diacrylate, which was used as a biobased comonomer along with AESO, ACO, or ADOD to form photo‐crosslinked polymer networks. The synthesis of acrylate derivatives was confirmed using FT‐IR and ¹H‐NMR spectroscopic techniques. The composition of the reaction mixture was changed to obtain crosslinked polymer networks with various mechanical properties. The addition of 2,5‐furan diacrylate increased the tensile strengths of the polymer films by up to 1.4–4.2 times relative to those obtained without the addition. These fully biobased polymers derived from vegetable oil and sugar can be used as environmentally friendly renewable materials for various applications to replace the existing petroleum‐based polymers currently used. Copyright © 2013 John Wiley & Sons, Ltd.     

Development of biobased polyurethane‐imides from maleinized cottonseed oil and castor oil

An eco‐friendly coating system, which is largely biobased, has been developed from castor and cottonseed oil. Cottonseed oil was functionalized with maleic anhydride by “ene” reaction to give maleinized cottonseed oil (MACSO); the anhydride groups were reacted with isocyanates to yield –NCO terminated polyurethane prepolymer. The prepolymer was further chain extended with hydroxyl groups of castor oil to give polyurethane‐imides (PUIs). The cross‐linked films thus obtained had good mechanical properties, and the imide groups in the backbone improved the corrosion resistance of PUIs as revealed by potentiodynamic polarization study. With increasing content of MACSO, thermal stability, glass transition temperatures (T_g), tensile strength, and corrosion resistance of resulting PUIs significantly increased.     

光/潮气双重固化聚氨酯涂层的制备及性能研究

以甲苯-2,4-二异氰酸酯(TDI)和二乙醇胺(DEOA)为原料一步法合成了超支化聚氨酯,对其改性制备了光固化超支化聚氨酯丙烯酸酯(HPUA)和一系列双重固化(UV/潮气)超支化聚氨酯丙烯酸酯(DHPUA),使用傅立叶红外光谱(FT-IR)、核磁共振氢谱(1H-NMR)和碳谱(13C-NMR)以及凝胶色谱(GPC)对其分子结构进行了表征.并以其为预聚物制备光固化涂层,通过对双重固化涂层的表面形貌、热性能和物理性能的研究,结果表明,超支化双重固化涂层经过潮气固化后,涂层表面的粗糙度随着树脂中硅氧烷端基的含量的增加先下降后上升;超支化双重固化涂层的物理性能和热稳定性都随着树脂中硅氧烷端基的含量的增加而提升.     

巯基-烯光点击反应辅助合成多官能度蓖麻油基聚氨酯丙烯酸酯

研究巯基-烯光点击反应辅助合成多官能度蓖麻油基聚氨酯丙烯酸酯。首先通过光引发的巯基-烯点击反应,于蓖麻油分子上引入巯基乙醇,形成多羟基化合物,然后加入丙烯酸羟丙酯与异佛尔酮二异氰酸酯,以物质的量为1:1反应得到端异氰酸酯丙烯酸酯,最终得到蓖麻油基聚氨酯丙烯酸酯。通过调节羟基含量可以得到不同官能度的丙烯酸酯。采用红外光谱、核磁氢谱、热重分析等手段表征其结构和性能,并测试了合成的聚氨酯丙烯酸脂的吸水率、附着力等性能,同时考察了它的热稳定性。结果表明, 在紫外光照射下,巯基和不饱和双键之间发生了加成反应;该聚合物的固化膜性能得到提高,尤其是硬度和热稳定性。由本文快速合成方法得到的树脂性能良好,具有较好的应用前景,扩大了巯基-烯光点击反应在高性能UV固化材料方面的应用范围。     

Biobased polyurethane adhesive over petroleum based adhesive: Use of renewable resource

This review article is based on the recent trends and development of biobased polyurethane (PU) adhesives from vegetable oil. A detail discussion has been reported about the PU adhesive starting from petroleum based to biobased source. Special attention has been given towards the utilization of castor oil based PU in adhesive technology, due to the wide range of castor oil among all vegetable oil. The appreciable adhesion, mechanical, thermal properties of vegetable oil based PU adhesives were compared with petroleum based PU adhesive, which were utilized to meet the specific application in adhesion industry.     

Preparation and thermal properties of a novel UV‐cured star polyurethane acrylate coating

A novel star polyurethane acrylate (SPUA) used for UV‐curable coating was prepared from 2,4‐toluene diisocyanate, 2‐hydroxyethyl arcylate, and hexakis(2‐hydroxyethyl)melamine, and characterized using FTIR, ¹H‐NMR, and elemental analysis. Its UV curing behaviors investigated via FTIR clearly indicated that this monomer could be cured rapidly at air atmosphere. The conversion of the unsaturated bond of the cured monomer sample is near to 72% after exposed under UV light for 40 sec. The hardness, flexibility, and mechanical properties of the cured film were also investigated. The thermal stability of the cured film was studied using thermogravimetric analysis (TGA) and real time Fourier transform infrared (RTFTIR). Results showed that this oligomer has some superior properties and can be used for UV curing coating. Copyright © 2007 John Wiley & Sons, Ltd.     

The maleimide modified epoxy resins for the preparation of UV‐curable hybrid coatings

In the present study, maleimide‐modified epoxide resin containing UV‐curable hybrid coating materials were prepared and coated on polycarbonate substrates in order to improve their surface properties. UV‐curable, bismaleimide‐modified aliphatic epoxy resin was prepared from N‐(p‐carboxyphenyl) maleimide (p‐CPMI) and cycloaliphatic epoxy (Cyracure‐6107) resin. The structure of the bismaleimide modified aliphatic epoxy resin was analyzed by FTIR and the characteristic absorption band for maleimide ring was clearly observed at 3100 cm^?1. Silica sol was prepared from tetraethylorthosilicate (TEOS) and methacryloxy propyl trimethoxysilane (MAPTMS) by sol–gel method. The coating formulations with different compositions were prepared from UV‐curable bismaleimide‐based epoxy oligomer and sol–gel mixture. The molecular structure of the hybrid coating material was analyzed by ²⁹Si‐CP/MAS NMR spectroscopy techniques. In the ²⁹Si CP/MAS NMR spectrum of the hybrid coating, mainly two kinds of signals were observed at ?68 and ?110 ppm that correspond to T³ and Q⁴ peaks, respectively. This result shows that a fully condensed structure was obtained. The thermal and morphological properties of these coatings materials were investigated by using TGA and SEM techniques. Hardness and abrasion resistance properties of coating materials were examined and both were found to increase with sol–gel precursor content of the coating. The photopolymerization kinetics was investigated by using RT‐IR. 70% conversion was attained with the addition of 15 wt% of BMI resin into the acrylate‐based coating formulation. It was found that the UV‐curable organic–inorganic hybrid coatings improved the surface properties of polycarbonate. Copyright © 2009 John Wiley & Sons, Ltd.     

PET光学膜紫外光固化硬涂层的制备

本文以改性聚氨酯丙烯酸酯为主体,制备了一种PET光学膜用透明硬涂层材料.讨论了光固化树脂、活性稀释剂、光引发剂等因素对PET光学膜加硬后的硬度、耐磨性、附着力等性能的影响,并从反应机理方面分析探讨了实验结果.经测试:实验制备的涂层硬度5H,附着力100%,经RCA纸带耐磨擦试(500g,1000cycles),PET膜可见光透过率无损失,同时具有低表面张力,出色的柔韧性和良好的耐化学品性.     

UV‐curable acrylate‐based nanocomposites: effect of polyaniline additives on the curing performance

Composites of nanostructured polyaniline (PANI) conducting polymer in a polyester acrylate (PEA) formulation were made to provide conductive organic coatings. The effect of the presence and amount of PANI on the photocuring performance of the ultraviolet (UV)‐curable acrylate system has been investigated employing real‐time Fourier transform infrared spectroscopy as the main technique. Longer initial retardation of the radical polymerization and lower rates of cross‐linking reactions were observed for dispersions containing PANI of higher than 3wt.%. The PEA/PANI samples were more affected than the neat PEA resin by the changes in UV light intensity and oxygen accessibility during UV curing. Samples with higher PANI content, of up to 10wt.%, were tested and could be partially cured even at UV light intensities as low as 2 mW cm^?2 when the oxygen replenishment into the system was inhibited. Thermal analysis revealed that the presence of PANI did not induce any significant change in Tg of the cured system, meaning that early decrease in mobility and vitrification is not the reason for lower ultimate conversion of the dispersions with higher PANI content compared with the neat PEA resin. Curing under strong UV lamps, of 1.5 W cm^?2 intensity, made it possible to reach high degrees of conversion on films with similar mechanical properties independent of the PANI content. Copyright © 2013 John Wiley & Sons, Ltd.     

Investigation of ultraviolet curable waterborne polyurethane acrylate dispersion based on hydroxyl-terminated polybutadiene

A new kind of ultraviolet (UV) curable waterborne polyurethane acrylate dispersion was synthesized based on hydroxyl-terminated polybutadiene (HTPB), poly-(propylene glycol) (PPG), isophorene diisocyanate (IPDI), 2-hydroxy ethyl acrylate (HEA) and dimethylol propionic acid (DMPA) after neutralizing by triethylamine (TEA). 2-Hydroxy-1-[4-2-hydroxyethoxy) phenyl]-2-methyl-1-propanone (Irgacure 2959) was used as a photoinitiator and deionized water as a diluent. Fourier transform infrared (FTIR) analysis was used to identify the chain structure of the UV-curable polyurethane prepolymer based on HTPB and the curing process. Effects of relative content of HTPB and PPG on emulsion stability, resistance to water and ethanol, thermal stability, compatibility of soft and hard segment, as well as the mechanical property of the cured film were investigated. Translated from Polymer Materials Science and Engineering, 2006, 22(3): 199–203 (in Chinese)     

Preparation and characters of hyperbranched polyester‐based organic‐inorganic hybrid material compared with linear polyester

To compare the properties of hyperbranched polymers with linear oligomers for preparing organic‐inorganic hybrids, hyperbranched aliphatic polyester (Boltorn^TM H20) and linear polyester hexa‐acrylate (EB830) were selected as organic components for preparing UV‐curable transparent hybrid materials using 3‐(trimethoxysilyl) propylmethacrylate as a coupling agent via a sol‐gel process. The prehydrolyzed product of tetraethoxysilane was used as an inorganic component. The effects of inorganic content on the morphologies, thermal behaviors, photopolymerizaiton kinetics and mechanical properties of the hybrids were investigated. The results show that for hyperbranched polyester‐based hybrids, the organic phase shows much better compatibility with inorganic phase even at high inorganic component content due to its special spheral shape and plenty of functional end groups, compared with linear EB830‐based hybrids. Copyright © 2004 John Wiley & Sons, Ltd.     

紫外光固化聚氨酯丙烯酸酯树脂的流变行为

合成了一系列紫外光因化聚氨酯丙烯酸酯聚合物,研究了分子量、原料配比、反应方式、含水量、溶剂等对其流变行为的影响。实验表明,控制剂聚物分子量,干燥原料,以ＨＥＡ先与异氰酸酯反应的加料方式合成的树脂,流动性较好。在此基础上合成了较好流动性和光固化性能的蓖麻油紫外光固化树脂。     

Linseed oil‐based reactive diluents preparation to improve tetra‐functional epoxy resin properties

Two kinds of bio‐resourced reactive diluents have been synthesized from linseed oil. The prepared epoxidized linseed oil (ELO) and the cyclocarbonated linseed oil (CLO) were separately blended with a petroleum‐based tetra‐functional epoxy resin (TGDDM) to improve its processability and to overcome the brittleness of the thermoset network therefrom. The linseed oil modifications were spectrally established, and processability improvement of the resin blends was rheologically confirmed. The curing of samples was studied by differential scanning calorimetry, and their mechanical properties (ie, tensile, flexural, fracture toughness, and adhesion) were investigated as well. Scanning electron microscopy images were obtained to reconfirm the toughness improvement of the modified thermosets. In contrast of the epoxidized soybean oil (ie, the most conventionally studied bio‐based reactive diluent), ELO and CLO had no negative effects on the thermoset material characteristics. They improved properties such as tensile strength (up to 43.2 MPa), fracture toughness (1.1 MPa m^1/2), and peel‐adhesion strength (4.5 N/25 mm). It was concluded that ELO and CLO were efficient reactive diluents to be used in formulations of polymer composites, surface coatings, and structural adhesives based on epoxy resins.     

Thiol-ene UV-curable coatings using vegetable oil macromonomers

Allyl, acrylate, and vinyl ether derivatives of castor oil were synthesized and blended with multifunctional thiols for evaluation as thiol-ene ultraviolet (UV) curable systems. The UV cured films were characterized and evaluated via ASTM tests, gel content, and dynamic mechanical analysis (DMA) as a function of time. Fourier transform infrared spectroscopy and DMA studies established that property advancement resulted from auto-oxidation, continued thiol-ene polymerization, or a combination of both mechanisms.     

Synthesis of Vegetable Oil‐Based Polyurethane: A Study on Curing Kinetics Behavior

In the present study, biobased polyurethane (BPU) samples were synthesized from three different polyols along with polymeric hexamethylene diisocyanate. The three different polyols were synthesized by reacting castor oil with ethylene glycol, triethylene glycol, and triethanolamine. The synthesized polyols were confirmed using proton nuclear magnetic resonance (¹H NMR) spectra analysis. BPU samples were confirmed by the disappearance of isocyanate peak in the FTIR spectra. The cross‐linking densities of all BPU samples were determined using swelling studies. Curing kinetics behavior of all BPU samples were analyzed using differential scanning calorimetry at three different heating rates (5, 7.5, and 10°C/min). The curing kinetic parameters were studied using three nonisothermal methods such as Kissinger, Flynn–Wall–Ozawa, and Ozawa, respectively. The activation energies were found to increase with increasing degree of cure (α). Surface properties of all the synthesized BPU samples were evaluated by dynamic mechanical analysis and scanning electron microscopy.     

Photocuring kinetics of UV‐initiated free‐radical photopolymerizations with and without silica nanoparticles

We used photodifferential scanning calorimetry to investigate the photocuring kinetics of UV‐initiated free‐radical photopolymerizations of acrylate systems with and without silica nanoparticles. Two kinetics parameters—the rate constant (k) and the order of the initiation reaction (m)—were determined for hybrid organic–inorganic nanocomposite systems containing different amounts of added silica nanoparticles (0–20 wt %) and at different isothermal temperatures (30–100 °C) using an autocatalytic kinetics model. The kinetic analysis revealed that the silica nanoparticles apparently accelerate the cure reaction and cure rate of the UV‐curable acrylate system, most probably due to the synergistic effect of silica nanoparticles during the photopolymerization process. However, a slight decrease in polymerization reactivity that occurred when the silica content increased beyond 15 wt % was attributed to aggregation between silica nanoparticles. We also observed that the addition of silica nanoparticles lowered the activation energy for the UV‐curable acrylate system, and that the collision factor for the system with silica nanoparticles was higher than that obtained for the system without silica nanoparticles, indicating that the reactivity of the former was greater than that of the latter. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 658–670, 2005     

Polyurethanes from polyols obtained by ADMET polymerization of a castor oil‐based diene: Characterization and shape memory properties

The acyclic diene metathesis polymerization (ADMET) of 1,3‐di‐10‐undecenoxy‐2‐propanol, a castor oil based diene, is reported. 10‐Undecenol was used as renewable comonomer to end‐cap polymer chains and limit the molecular weight. The poly ols obtained in this way were reacted with 4,4′‐methylenebis(phenylisocyanate) (MDI) to yield a series of amorphous and semicrystalline polyurethane networks. The thermal stability and the thermomechanical and mechanical properties of these thermosets have been studied and showed good shape memory properties for the semicrystalline polymer. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Free radical and thermal curing of terpyridine‐modified terpolymers

Terpolymers bearing terpyridine as well as (meth)acrylates as free radical curable groups (UV‐curing) or hydroxyl groups (thermal curing with bis‐isocyanates) were synthesized and characterized using ¹H NMR, IR and UV‐vis spectroscopy as well as GPC. Subsequently, the ability of covalent crosslinking via the UV‐initiated polymerization of the acrylate groups was investigated. Moreover, the thermal covalent crosslinking via the reaction of hydroxyl functionalized terpolymer and bis‐isocyanate compounds could be successfully achieved. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4028–4035, 2004     

Synthesis and characterization of UV‐curable phosphorus containing hybrid materials prepared by sol–gel technique

In this study, a series of ultraviolet (UV)‐curable organic–inorganic hybrid coating materials containing phosphorus were prepared by sol–gel approach from acrylate end‐capped urethane resin, acrylated phenyl phosphine oxide oligomer (APPO), and inorganic precursors. TEOS and MAPTMS were used to obtain the silica network and Ti:acac complex was employed for the formation of the titania network in the hybrid coating systems. Coating performance of the hybrid coating materials applied on aluminum substrates was determined by the analysis techniques, such as hardness, gloss, impact strength, cross‐cut adhesion, taber abrasion resistance, which were accepted by international organization. Also, stress–strain test of the hybrids was carried out on the free films. These measurements showed that all the properties of the hybrids were enhanced effectively by gradual increase in sol–gel precursors and APPO oligomer content. The thermal behavior of the hybrid coatings was investigated by thermogravimetric analysis (TGA) analysis. The flame retardancy of the hybrid materials was examined by the limiting oxygen index (LOI); the LOI values of pure organic coating (BF) increased from 31 to 44 for the hybrid materials containing phosphorus (BF‐P:40/Si:10). The data from thermal analysis and LOI showed that the hybrid coating materials containing phosphorus have higher thermal stability and flame resistance properties than the organic polymer. Besides that, it was found that the double bond conversion values for the hybrid mixtures were adequate in order to form an organic matrix. The polycondensation reactions of TEOS and MAPTMS compounds were also investigated by ²⁹Si‐NMR spectroscopy. SEM studies of the hybrid coatings showed that silica/titania particles were homogenously dispersed through the organic matrix. In addition, it was determined that the hybrid material containing phosphorus and silica showed fibrillar structure. Copyright © 2009 John Wiley & Sons, Ltd.