耐高温TTOA-环氧树脂的合成及表征

以桐油酸酐(TOA)和三(2-羟乙基)异氰脲酸酯(THEIC)为原料,合成了赛克-桐油酸酐(TTOA)固化剂,然后用TTOA固化环氧树脂E44得到TTOA-E44树脂.TTOA-E44树脂的热差分析(TGA)的实验结果表明:固化树脂的耐热指数高达174 ℃,表观分解温度高达356 ℃,抗热老化性能和弯曲强度优于同类固化剂的固化物.     

单组分环氧胶粘剂用固化剂

日本味之素精细化学株式会社制造的单组分环氧胶粘(AH-154、AH-162)、二酰肼(VDH、UDH)、叔胺缩合物(MY的良好促进剂。剂用固化剂有咪唑加成物(PN-23、PN-31、PN-40)、双氰胺改性物24)，能使环氧树脂在较低温度下快速固化。还能用作酸酐固化剂     

桐油改性处理对PE木塑复合材料性能的影响

采用桐油改性处理木粉,分析了固化剂的组成对桐油固化时间的影响;桐油的含量对木塑复合材料吸水率、力学性能以及防霉性能的影响。结果表明:固化剂和催干剂的添加明显缩短了桐油的固化时间,当环烷酸钴重量为1份,H_2O_2为14份,固化时间为14 min时,具有较快的固化时间和固化效果;用桐油改性处理木粉可显著降低木塑复合材料的吸水率;随着桐油含量的增加,吸水率明显降低,当桐油含量达到8%时,40 d的吸水率为10.7%;且木塑复合材料的吸水率越低,其吸水后强度的变化越小;防霉结果显示,桐油的处理对木塑材料的防霉抑菌具有一定的效果。     

中温潜伏性固化剂在环氧胶黏剂中的研究进展

在环氧胶黏剂体系中,中温潜伏性固化剂以其优异的潜伏性和相对较低的固化温度而成为研究热点,符合当下提倡的绿色、环保、"低碳生活"理念。详细介绍了双氰胺、咪唑、酸酐、有机酰肼、BF3-胺络合物、微胶囊六种中温潜伏性固化剂及其改性方法。它们的改性方法主要是:通过改性活化或者加入活性促进剂降低双氰胺、酸酐、有机酰肼等高温固化剂的固化温度;通过改性钝化咪唑的固化活性,延长室温储存期;将BF3等路易斯酸室温固化的固化剂与胺络合降低其固化活性,提高室温储存期;将活性固化剂用壁材包裹形成微胶囊使其在室温时稳定,较高的温度时壁材破裂释放出活性固化剂,迅速固化。     

丙烯酸酯改性桐油基乳化剂的合成、表征及光固化性能

桐油和马来酸酐经Diels-Alder反应形成桐油二酸酐(TM2)、桐油三酸酐(TM3),桐油三酸酐与不同比例的甲基丙烯酸β羟乙酯(HEMA)反应,将桐油三酸酐及其与HEMA反应物中的酸酐官能团水解,合成出含3~6个羧基官能团丙烯酸酯改性的桐油衍生物。产物结构经红外光谱和核磁共振氢谱表征。测定了桐油基衍生物钠盐的表面张力及CMC值,考察了改性桐油基乳化剂对丙烯酸酯类单体及低聚物的乳化性能。结果表明,随着桐油基衍生物中的羧酸钠基团的增加,衍生物的亲水性增强,CMC值呈上升趋势,乳化性能增强。丙烯酸酯改性桐油基衍生物及其复配物可以光固化,可以通过调节光固化体系的组分得到耐水性很好的光固化膜。     

桐油改性胺固化剂

<正> 湖南省洪江市树脂厂利用山区丰富的桐油资源与岳阳化工总厂研究院共同研制开发国内最新化工产品——桐油改性胺固化剂,最近获得成功,并投入批量生产,年产量可达400吨。 国内目前使用的胺类固化剂存在活性较强、易挥发,毒性和刺激性较大,生产过程污染严重,固化后的固化物易脆,机械性能较差等缺点。     

HPM/St/MA三元共聚物固化E-44环氧树脂的研究

制备了N-(4-羟基苯基)马来酰亚胺/苯乙烯/马来酸酐三元共聚物,并将其用做固化剂对E-44环氧树脂进行耐热改性。对固化物的耐溶剂性进行了测定,结果表明HPM/St/MA固化后的E-44环氧树脂具有很好的的耐溶剂性能;采用TG热分析技术研究了E-44环氧树脂固化物的耐热性能,结果表明加入相同比例活性含量的改性剂时HPM/St/MA比其它常见的固化剂固化效果更好,耐热性更高。     

聚硫橡胶改性环氧室温快干重防腐涂料的制备

用不同量的端巯基液体聚硫橡胶(PSR)对酚醛环氧树脂(F-51)进行改性,合成F-51/PSR预聚物,并用3种不同的固化剂(聚酰胺固化剂PA650、环氧酚醛胺固化剂T-31、腰果壳油改性胺固化剂NX-5454)分别对其进行固化。用红外光谱(FT-IR)对F-51/PSR预聚物的分子结构进行了表征。通过对改性环氧固化物拉伸性能的测试和用扫描电子显微镜(SEM)对固化物断面形貌的分析,评价了该固化物的增韧效果并分析了其增韧机理。此外还通过差示扫描量热仪(DSC)和热重(TGA)对涂膜的固化行为与热稳定性能进行了研究。结果表明PSR可以有效增韧F-51树脂,采用NX-5454为固化剂,当m(PSR)∶m(F-51)=0.2时,涂膜柔韧性和干燥速度得到了最有效提高,断裂伸长率从6.42%增长到18.25%,室温下涂膜1.5 h内表干,4.5 h内实干,达到了快速固化的要求。     

环氧树脂柔性固化剂研究综述

环氧树脂柔性固化剂种类众多,主要介绍改性脂肪族胺、脂环族胺、柔韧性酸酐、聚合物类环氧树脂柔性固化剂研究进展。认为对固化剂分子进行没计,开发合成柔性固化剂来增韧环氧树脂,可提高环氧固化物性能。     

环氧树脂柔性固化剂研究进展

环氧树脂柔性固化剂种类众多，主要介绍改性脂肪族胺脂环族胺、柔韧性酸酐、聚合物类环氧树脂柔性固化剂研究进展，认为对固化剂分子设计和开发合成柔性固化剂来增韧环氧树脂，可提高环氧固化物性能。     

桐油基水性光固化树脂的合成及性能研究

以生物质资源桐油（TO）、马来酸酐（MA）为原料,通过Diels-Alder反应合成了桐油酸酐,再以其与丙烯酸羟乙酯（HEA）反应,经中和水化制备了桐油基水性光固化树脂。通过红外光谱（FTIR）、核磁共振氢谱（1H NMR）表征了合成产物的分子结构。考察了TO、MA以及HEA的比例对桐油基水性光固化树脂的乳液性质、光固化活性以及涂膜性能的影响。研究结果表明,当n(TO):n(MA):n(HEA):n(TEA)= 1:2.5:2.5:2.5时,合成的桐油基水性光固化树脂的稳定性、光固化活性以及涂膜性能最优异。     

Synthesis and characterization of bio-based epoxy thermosets using rosin-based epoxy monomer

Iranian Polymer Journal - Acrylicpimaric acid-based epoxy (APA-based epoxy) and tung oil maleic anhydride (TMA), as a curing agent, were synthesized and used to prepare fully bio-based cured...     

桐油改性双环戊二烯不饱和树脂的合成研究

利用缩聚反应后期桐油与双环戊二烯不饱和聚酯(DCPD-UPR)主链上不饱和双键的Diels-Alder(D-A)反应合成了桐油改性DCPD-UPR,研究了各种原料用量对桐油改性DCPD-UPR其浇注体力学性能的影响。结果表明:当顺酐与苯酐的物质的量比为2∶1～3∶1,双环戊二烯与顺酐物质的量比为0.6～0.8∶1,1,2-丙二醇与二甘醇物质的量比2∶1,缩聚反应后期加入10%(质量分数)桐油,苯乙烯质量分数为35%～40%时,获得的桐油改性DCPD-UPR粘度适中,浇注体的断裂伸长率提高了78.2%,冲击强度提高了82.0%。     

Synthesis,characterization, and properties of acrylate‐modified tung‐oil waterborne insulation varnish

An acrylate‐modified tung‐oil waterborne insulation varnish was synthesized from tung oil, maleic anhydride, and acrylates via a Diels–Alder reaction and free‐radical polymerization, and the varnish could be solidified at a relatively low temperature with blocked hexamethylene diisocyanate as a curing agent. The resulting films were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The insulation properties (electrical insulation strength, volume resistivity, and surface resistivity) of the varnish films were tested, and the resistances of films to salted water were evaluated. With an increase in the maleic anhydride content, the thermal stability of the film was improved, whereas the electrical insulation strength, volume resistivity, and surface resistivity decreased. The electrical insulation strength of the film after it was immersed in the NaCl solution was lower than that in dry state, and it decreased as the immersed time was prolonged. In particular, the electrical insulation strength loss of the film increased significantly at maleic anhydride contents beyond 25 wt %. Furthermore, the hardness of the film increased with increasing methyl methacrylate/N‐butyl acrylate ratio, whereas the flexibility and adhesion of film decreased to a certain degree at the same time. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41608.     

桐油改性双环戊二烯不饱和树脂的固化研究

采用红外光谱(FT-IR)和示差扫描量热法(DSC)对桐油改性DCPD-UPR的固化特性和固化动力学进行了研究。利用Kissinger方程和Crane方程计算得到桐油改性DCPD-UPR的表观活化能94.03 kJ/mol,反应级数为0.94,指前因子为2.185×1012。利用T-β外推法确定了桐油改性DCPD-UPR的固化温度为107.28℃,后处理温度为120.65℃。较未改性的DCPD-UPR,桐油改性DCPD-UPR的固化放热曲线平缓,放热峰温度低,固化时间长,可以避免树脂固化成型时翘曲、开裂等现象的发生。     

Preparation and properties of epoxy‐modified tung oil waterborne insulation varnish

This work aimed to develop a novel epoxy‐modified tung oil waterborne insulation varnish with blocked hexamethylene diisocyanate as a curing agent. The Diels–Alder reaction between tung oil and maleic anhydride, and the ring‐opening esterification reaction of epoxy resin were confirmed. The conversion rate of epoxy was explored as a function of reaction time and temperature. The effects of epoxy resin content on the thermal stability, water absorption and insulation properties (insulation strength, volume resistivity, and surface resistivity) of films were investigated, and the resistances of films to salted water were evaluated. The increase in epoxy resin contents could improve the thermal stability and insulation properties of films, and decreased the water adsorption of films, but when the epoxy resin content reached 30% and above, the water solubility of resin became poor. After being immersed in 3.5 wt % NaCl solution, the electrical insulation strength of films were lower than that in dry state, and decreased as the immersed time prolonged. In particular, the electrical insulation strength loss of films increased significantly for epoxy resin content at 15% and below. Furthermore, the increase of epoxy resin content could improve the hardness and adhesion of films, but the flexibility of films became worse. On the basis of experimental, the epoxy resin content at 25% was appropriate to prepare waterborne epoxy‐modified tung oil resin. The resulting varnish may have potential as an immersing insulation varnish for the spindle of electric motor. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42755.     

Curing behavior of epoxy resin/tung oil anhydride exfoliated nanocomposite by differential scanning calorimetry

The nanocomposite of epoxy resin/tung oil anhydride/organic montmorillonite was prepared by casting and curing. The distance of the clay gallery rose and the exfoliated nanocomposite was formed. The exfoliation behaviors of the nanocomposite had been investigated by X‐ray diffraction (XRD). The curing mechanism and kinetics of epoxy resin with the different amounts of organic montmorillonite were studied using isothermal and dynamic methods by differential scanning calorimetry (DSC). Some parameters, the activation energy and reaction orders, were calculated by the modified Avrami equation in analysis of the isothermal experiment. The total curing mechanism and kinetics of curing reaction were also analyzed by the Flynn–Wall–Ozawa method. It was noted that the instantaneous activity energy during the curing process could be obtained by the Flynn–Wall–Ozawa method and the trend of the results was in agreement with those obtained from the modified Avrami equation. These results show that the activity energy decreases with the addition of organic montmorillonite. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3822–3829, 2004     

Intercalation and exfoliation behavior of epoxy resin/curing agent/montmorillonite nanocomposite

The epoxy resin/curing agent/montmorillonite nanocomposite was prepared by a casting and curing process. The intercalation and exfoliation behaviors of epoxy resin in the presence of organophilic montmorillonite were investigated by X‐ray diffraction (XRD) and dynamic mechanical thermal analysis (DMTA). For the diethylenetriamine curing agent, the intercalated nanocomposite was obtained; and the exfoliated nanocomposite would be formed for tung oil anhydride curing agent. The curing condition does not affect the resulting kind of composite, both intercalation or exfoliation. For intercalated nanocomposite, the glass transition temperature T_g, measured by DMTA and affected by the curing temperature of matrix epoxy resin is corresponded to that of epoxy resin without a gallery. The α′ peak of the loss tangent will disappear if adding montmorillonite into the composite. It was also found that the T_g of the exfoliated nanocomposite decreases with increasing montmorillonite loading. © 2002 John Wiley & Sons, Inc. J Appl Polym Sci 84: 842–849, 2002; DOI 10.1002/app.10354     

亚胺环氧型少溶剂绝缘浸渍漆的研究

以部分酰亚胺化的桐油酸酐、酚醛树脂作为双酚A型环氧树脂的固化剂,纯化咪唑为固化促进剂,以甲苯和乙醇为混合溶剂,运用正交试验方法研制出固体含量70％,耐温指数159.4℃(>155℃),各项性能良好的少溶剂绝缘浸渍漆。     

Modification of tung oil–based polyurethane foam by anhydrides and inorganic content through esterification process

In this study, we have reported the synthesis of modified polyol from tung oil. The synthesis involves three steps: first, conversion of tung oil to hydroxylated tung oil by hydroxylation; second, alcoholysis with triethanolamine; and finally, the esterification of polyester polyol when reacted with phthalic anhydride (PA) or maleic anhydride (MA). Boric acid is also introduced into the polyol by chemical modification, which enhances the thermal properties of polyurethane foam (PUF). PUF is formulated by the reaction between polyol and isocyanate. A systematic comparison of flame retardancy and mechanical and thermal properties of modified PUF has been examined. The structural properties of modified polyol were characterized by Fourier transform infrared spectroscopy, proton NMR spectroscopy, and gel permeation chromatography, while the thermal and mechanical properties of the formulated PUF were studied by scanning electron microscopy, limiting oxygen index, differential scanning calorimetry, Izod impact, and flexural and compression strength. Thus PUF prepared from modified polyol with a proper distribution of soft and hard segments possesses better mechanical and thermal properties. The PA‐modified foams show better properties compared to unmodified and MA‐modified foams due to the aromaticity and crosslinking behavior of PA. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45786.