茶油基水性胺类环氧固化剂的结构与性能

以茶油皂脚脂肪酸甲酯为原料制备水性胺类环氧固化剂,通过热失重分析、力学性能测试等考察了封端剂种类、n(四乙烯五胺TEPA)∶n(单环氧甲基四氢邻苯二甲酸双酯SEMeTHP-DE)、脂肪醇聚氧乙烯醚(AEO)的聚合度及n(环氧)∶n(胺氢)对涂膜性能的影响。结果表明,选择苄基缩水甘油醚为封端剂,物质的量比n(TEPA)∶n(SEMeTHP-DE)为1.2∶1,聚合度为4的AEO(AEO-4)为亲水扩链剂制备的水性胺类环氧固化剂与水性环氧乳液AB-EP-20按n(环氧):n(胺氢)之比1.2∶1进行固化时,涂膜性能最佳,此时漆膜柔韧性1mm、铅笔硬度2H、附着力1级、耐冲击性≥50 kg.cm、耐水性(25℃)≥3d、耐乙醇性(25℃)≥3d。     

水性含磷环氧化合物的合成与性能

对9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)改性合成水性含磷环氧化合物。首先,以酚醛环氧树脂F-51和DOPO(初始F-51环氧基与DOPO摩尔比为3∶2)合成出F-51-DOPO加成物。然后,在摩尔比(n(F-51-DOPO的环氧基)/n(MEA))为1∶1下,F-51-DOPO加成物与乙醇胺(MEA)反应合成出F-51-DOPO-MEA加成物;最后,在摩尔比(PEGGE环氧基/F-51-DOPO-MEA)为2∶1下,F-51-DOPO-MEA加成物与聚醚醇二缩水甘油醚(PEGGE)反应,合成了F-51-DOPO-MEA-PEGGE加成物。性能研究结果表明,其在室温下能均匀分散于水性体系中,与涂膜中的环氧树脂基材相容性良好;并可使涂膜在保持良好硬度前提下,耐冲击性明显得到提高。热重分析结果表明,其可使固化涂膜在450~800℃高温下的残炭率和耐热性显著提高。氧指数测定结果表明,其能有效提高水性环氧树脂材料的极限氧指数(LOI)及阻燃性能。     

水性环氧固化剂制备及其对涂膜性能的影响

将环氧树脂E-44与三乙烯四胺(TETA)形成的加成物接枝到聚天冬酰胺(PAM)大分子链上,形成聚酰胺-胺-环氧梳形接枝聚合物,以丁基缩水甘油醚部分封端,制备了非离子型水性环氧固化剂。研究了PAM接枝该加成物的比率、接枝加成物在加成物中的含量、伯胺封端量对固化剂性能的影响,并与市售水性环氧涂膜性能进行了比较。试验结果表明,多胺加成物接枝率20%、接枝含量25%、伯胺封端量25%的固化剂体系稳定性良好,与现有的市售水性固化剂性能相比,其固化的环氧体系的柔韧性和耐冲击性能有大幅的提高。     

水性环氧涂料的固化机理及性能

采用IR验证非离子型自乳化水性环氧固化剂的结构,并表征其物理性质。通过TEM观察固化前与固化后乳液颗粒的形貌来阐述非离子型水性环氧涂料的固化机理,并探讨脂肪胺的种类、胺氢与环氧比及固化温度对涂料性能的影响。结果表明,这种非离子型水性环氧固化剂的固化过程受到水分的挥发速度,颗粒的聚集程度,乳液颗粒的大小、形貌,以及固化剂的扩散速度和固化速度的影响。并认为最佳脂肪胺是TETA,胺氢与环氧摩尔比为0.8∶1～1.2∶1,含水量为30%～40%,固化温度在30℃～50℃。     

水性环氧固化剂的合成及性能

以三乙烯四胺(TETA)和液体环氧树脂(EPON828)为原料,在物料摩尔比(TETA/EPON828)为2 2/1,反应温度为 65℃,反应时间为 4h的工艺条件下合成 EPON828 TETA加成物。然后用具有多支链柔韧性链段的 C12 ~ 14 叔碳酸缩水甘油酯(CARDURA E -10) 在反应温度为70℃,反应时间为 3h的工艺条件下对 EPON828- TETA加成物进行封端改性。探讨了中和度对所合成的水性环氧固化剂的粒径及稳定性的影响。CARDURA E- 10 改性后的水性环氧固化剂与液体环氧树脂在室温下固化所形成的涂膜性能良好,其柔韧性和耐冲击性优于用传统封端改性剂 BGE 或CGE改性水性环氧固化剂所形成的涂膜。     

水性超支化聚合物/水性环氧树脂体系的固化行为及性能

利用马来酸酐和丁基缩水甘油醚对超支化聚合物端基改性,得到以羧基和羟基为末端的超支化聚合物,其中和成盐后即得水性超支化聚合物(WHPs),通过红外光谱(FT-IR)和核磁共振(1H-NMR)对初始聚合物和改性聚合物的结构进行了表征。然后将WHPs应用于水性环氧涂料中,以差示扫描量热法对体系的固化行为进行了分析,研究了其固化动力学,并且研究了不同含量WHPs对体系固化涂层力学性能的影响。结果表明,该固化体系的表观活化能较低,固化反应容易进行,该WHPs的加入促进了体系固化反应,能够较好地改善涂膜的力学性能。当WHPs的加入量为10%时,涂层的综合力学性能达到最佳。     

水性UV固化涂料用多羟甲基苯酚丙烯酸酯的合成

以多羟甲基苯酚钠和丙烯酰氯为原料,合成了适用于水性UV固化涂料的多羟甲基苯酚丙烯酸酯,通过红外光谱表征了产物的化学结构。探讨了物料比、反应温度、反应时间和催化剂用量等因素对产物产率的影响,结果表明:当n(多羟甲基苯酚钠)∶n(丙烯酰氯)=1∶2、反应温度为0～-5℃、反应时间为2.5h、催化剂四丁基溴化铵用量为0.04%(占物料质量比)时,最有利于产物的合成;多羟甲基苯酚丙烯酸酯的水溶性及涂膜性能,也能较好地满足水性UV固化涂料的应用。     

环氧改性水性聚氨酯的合成及因素分析

用异佛尔酮二异氰酸酯(IPDI)、聚丙二醇2000(PPG2000)、2,2-双(羟甲基)丙酸(DMPA)为主要原料合成预聚体,环氧树脂(E44)开环合成环氧改性水性聚氨酯(EWPU),考察了不同影响因素对EWPU乳液及胶膜性能的影响。首先,通过FT-IR证实了环氧改性水性聚氨酯的合成;然后,经过TG测试证明了改性后水性聚氨酯耐热性能优于水性聚氨酯;最后详细探究了DMPA量、—NCO与—OH的摩尔比(R值)、硬单体配比以及环氧量对EWPU乳液粒径、贮存稳定性、涂膜耐水性、涂膜耐磨性和力学性能的影响。结果表明,当DMPA量为5%、R值为1.5、硬单体配比为35%、EP量为8%时,EWPU乳液的综合性能最优。     

固化对水性环氧粘结固体润滑涂层理化及摩擦学性能的影响

为了确定水性环氧粘结固体润滑涂层的最佳固化条件,采用MFT-R 4000型往复摩擦磨损试验仪评价了不同固化条件对其摩擦学性能的影响,用傅立叶变换红外光谱(FTIR)和示差扫描量热法(DSC)表征手段,确定了体系的最佳固化条件.结果表明:固化条件不同,涂层的摩擦学性能差异很大;水性粘结剂与水性固化剂的最佳质量比为2:1,最佳固化温度为75℃,最佳固化时间为2 h;以最佳条件制备的水性环氧粘结固体润滑涂层具有优异的理化性能和摩擦学性能,摩擦磨损寿命比传统的有机溶剂型粘结固体润滑涂层约长30%.本研究为制备高性能环保型粘结固体润滑涂层提供了可能.     

涂料用有机硅、环氧复合改性水性聚氨酯的制备

选用异佛尔酮二异氰酸酯(IPDI)、聚己二酸1,4-丁二醇酯(PBA)、二羟甲基丙酸(DMPA)、1,4-丁二醇(BDO)为主要原料,用双酚A型环氧树脂和氨基硅烷复合改性制备水性聚氨酯。研究了体系中n(—NCO)∶n(—OH)、DMPA用量、环氧树脂与氨基硅烷的配比对乳液及涂膜的影响,并通过傅里叶红外光谱仪、粒径分析仪、接触角仪和热重分析仪(TGA)对乳液及涂膜进行了表征。结果表明:n(—NCO)∶n(—OH)为1.5∶1,DMPA用量为5%~7%,环氧树脂添加量为8%,氨基硅烷的用量为4%时,乳液外观及稳定性好,平均粒径为24.56nm;涂膜硬度达2H,吸水率仅为2.3%,耐热性显著提高;综合性能优异,可作为防腐蚀涂料用树脂,应用于多领域。     

新型水性环氧树脂固化剂合成及性能的研究

采用新的合成方法合成了水性环氧树脂固化剂,初步探讨了该水性固化剂的性质。先将双酚A与环氧氯丙烷按质量比1∶2反应生成氯醚醇,再与二乙烯三胺发生胺解反应,形成类似于盐酸化的环氧胺加成物,又以单氯醚醇封闭活性高的伯胺氢,然后用NaOH脱除所有的HCl,再加入有机酸成盐,即形成水性环氧树脂固化剂。同样,将聚乙二醇与环氧氯丙烷反应,再与多胺反应,可将水溶性的链段引入固化剂中,不仅提高了固化剂的水溶性,而且改善环氧树脂的韧性。     

快速固化环氧树脂及其碳纤维/环氧复合材料性能

采用双酚A型环氧树脂（DGEBA）、改性咪唑（MIM）及改性脂肪胺（MAA）研制快速固化树脂体系。分别利用DSC和流变仪测试了树脂体系的固化特性与流变行为,优选了树脂配方。采用真空辅助树脂灌注工艺（VARIM）制备了快速成型的碳纤维/环氧复合材料层板,考察了层板的成型质量和力学性能,并与常规固化的层板性能进行了对比。结果表明：采用优选的树脂配方,120 ℃下树脂在5 min内固化度达95%,碳纤维/环氧复合材料层板成型固化时间可控制在13 min以内,固化度达95%以上,并且没有明显缺陷;与常规固化相比（固化时间大于2 h）,快速固化碳纤维/环氧复合材料层板的弯曲性能和耐热性能降低幅度较小。     

耐高温聚氨酯改性TDE-85/E-51环氧树脂胶粘剂的制备和性能

以混合芳胺为固化剂,通过聚氨酯(PU)对4,5-环氧环己烷-1,2-二甲酸二缩水甘油酯(TDE-85)与二酚基丙烷缩水甘油醚(E-51)环氧树脂的改性,制备了一种高强高韧的耐高温环氧树脂结构胶粘剂。通过改变E-51、TDE-85、PU及固化剂之间的配比,探讨了各个组分对胶粘剂力学性能的影响。通过SEM分析,研究了PU增韧环氧树脂的机理。结果表明,TDE-85和E-51的配比为1∶1,PU添加量为环氧树脂的19%,芳胺固化剂添加量为20%时,胶粘剂具有最佳的耐热性和力学性能。制备的PU改性TDE-85/E-51结构胶粘剂室温拉伸剪切强度达到25.81 MPa,160℃高温拉伸剪切强度为12.85 MPa,剥离强度达到51.68 N/cm。     

Curing behavior and kinetic analysis of epoxy resin/multi-walled carbon nanotubes composites

The effect of multi-walled carbon nanotubes (MWNTs), both amino-functionalized (f-MWNTs) and unfunctionalized (p-MWNTs) on the curing behavior of epoxy resin (EP) cured with triethanolamine (TEA), was investigated using differential scanning calorimetry (DSC). Because the triethylenetetramine (TETA) grafted on the f-MWNTs could act as curing agent and the produced tertiary amine as negative ionic catalysts of curing reaction of EP, so the activation energy of the EP/TEA system was decreased by the addition of f-MWNTs. Viscosity played a key role in the curing behavior of the EP/TEA/MWNTs system, for high viscosity of the EP/TEA/MWNTs system could hinder the motion of the functional groups. The curing heat in EP/TEA/f-MWNTs (weight ratio 1/0.1/0.01) system was higher than the neat EP/TEA (weight ratio 1/0.1) system, while the curing heat in EP/TEA/p-MWNTs (weight ratio 1/0.1/0.01) was lower than the neat system. When the content of f-MWNTs was increased to 2 phr (weight ratio of 1/0.1/0.02), the curing heat became lower than that of the neat EP/TEA system, which was the result of the higher viscosity of the EP/f-MWNTs/TEA system. Since the curing heat indicated the curing degree of the system generally, the addition of the f-MWNTs was thought to increase the curing degree of the epoxy matrix at a relatively low content.     

硼胺络合物/环氧树脂体系的固化反应机理及其动力学

应用DSC 和IR 分析技术, 研究了含有口恶硼杂环的硼胺络合物与环氧树脂体系的固化反应机理和固化反应动力学。结果表明, 固化反应主要是硼胺络合物与体系中羟基化合物形成含氢质子的配位络合物, 然后由此引发体系的环氧基进行的阳离子开环聚醚反应, 整个体系的固化反应过程遵循一级动力学方程。      

环氧树脂预聚物分子量对其固化物性能的影响

本文着重研究了环氧树脂预聚物分子量对叔胺促进剂催化的酸酐固化剂固化的环氧树脂体系固化物电气、力学和耐热性能的影响。结果表明,环氧树脂预聚物分子量对性能有显着影响,且具有规律性。      

Characterization of double network epoxies with tunable compositions

This article reports the processing and characterization of epoxy resins with near constant molar cross-link density prepared from sequentially reacted amine cross-linking agents. Stoichiometric blends of curing agents with compositions ranging from all polyetheramine to all diaminodiphenylsulfone (DDS) are reacted with an epoxy monomer in a staged curing procedure. The low reactivity of the aromatic amine permits the selective reaction of the aliphatic amine in the first stage. The residual aromatic amine and epoxide functionality are reacted in a second stage at higher temperature. Above approximately 50% DDS content the first stage produces sol glasses which have not reached the gel point. The glass transition temperatures of the partially cured networks decrease monotonically with increasing DDS content. The partially cured networks can be characterized thermally and mechanically above their respective glass transitions without significantly advancing the reaction of the residual DDS and epoxide functionality. The networks formed after the second stage of the cure exhibit thermal and mechanical properties intermediate between those of the two individual amine cured networks, according to composition. The blends do not show any evidence of phase separation across the entire composition range in either the partially cured or fully cured state.     

Acrylonitrile-capped poly(propyleneimine) dendrimer curing agent for epoxy resins: Model-free isoconversional curing kinetics,thermal decomposition and mechanical properties

Acrylonitrile-modified aliphatic amine adducts are often used as curing agents for room-temperature epoxy formulations (coatings, adhesives, sealants, castings, etc.), yet the curing reaction and properties of resultant epoxy systems still remain less fundamentally understood. Herein we systematically investigate our newly-developed acrylonitrile-modified multifunctional polyamine curing agent for bisphenol A epoxy resin (DGEBA): an acrylonitrile-capped poly(propyleneimine) dendrimer (PAN4). The impact of the molecular structure of PAN4 and a controlled poly(propyleneimine) dendrimer (1.0GPPI) on the curing reactivity, reaction mechanisms, thermal stability, viscoelastic response and mechanical properties of the epoxy systems are highlighted. Differential scanning calorimetry (DSC) confirms DGEBA/PAN4 shows markedly lower reactivity and reaction exotherm than DGEBA/1.0GPPI, and the model-free isoconversional kinetic analysis reveals that DGEBA/PAN4 has the generally lower reaction activation energy. To be quantitative, the progress of the isothermal cure is predicted from the dynamic cure by using the Vyazovkin equation. The isothermal kinetic prediction shows that DGEBA/PAN4 requires about 10 times longer time to achieve the same conversion than DGEBA/1.0GPPI, which agrees with the experimentally observed much longer gel time of DGEBA/PAN4. Subsequently, dynamic mechanical analysis shows that PAN4 results in the cured epoxy network with the lower β- and glass-relaxation temperatures, crosslink density, relaxation activation energy, enthalpy, entropy, but the higher damping near room temperature than 1.0GPPI. Finally, thermogravimetric analysis (TGA) demonstrates cured DGEBA/PAN4 is thermally stable up to 200 °C, and mechanical property tests substantiate that PAN4 endows the cured epoxy with much higher impact and adhesion strengths than 1.0GPPI. Our data can provide a deeper insight into acrylonitrile-modified aliphatic amine curing agents from the two good model compounds (PAN4 and 1.0GPPI).     

环氧树脂/聚醚胺柔性导电油墨的制备与性能

以聚醚胺为固化剂、环氧树脂E-51为粘接树脂、银包铜粉为导电填料制备了环氧树脂/聚醚胺柔性导电油墨,用红外光谱和差示量热扫描分析对环氧树脂/聚醚胺D-400体系的固化条件进行了表征,讨论了导电油墨体积电阻率的影响因素;并研究了聚醚胺D-2000与D-400不同质量比对油墨的柔韧性、附着力、体积电阻率的影响。结果表明,环氧树脂/聚醚胺D-400导电油墨的体积电阻率随着固化剂D-400用量、导电填料含量、固化时间的增长均先减小后趋于稳定;当聚醚胺D-2000/D-400的质量比从0增加到0.6时,导电油墨的柔韧性提高了67.9%,对聚对苯二甲酸乙二醇酯(PET)基材的附着力等级仍为0级,体积电阻率增大了40.6%。