Mannich反应制备壬基酚改性胺固化剂

本文介绍了采用壬基酚和甲醛对(2,3二甲基)二亚丁基三胺(TAB)的改性研究,考察了不同反应温度和配比对合成反应的影响。并通过TAG-DTA研究了本实验制成的固化剂与环氧树脂固化反应过程的热效应。表明采用壬基酚合成的曼尼希碱,起始反应温度虽高,但反应比较温和,易于控制,产品可用作环氧树脂固化剂。     

Mannich改性间苯二甲胺环氧树脂固化剂的制备及水下粘接性能

以壬基酚、甲醛和间苯二甲胺(MXDA)为主要原料,采用曼尼希加成法合成了一种疏水型改性胺固化剂。研究间苯二甲胺、壬基酚、甲醛3者配比及反应时间、反应温度等因素对改性胺黏度和水下粘接强度的影响,采用控制变量法优选出改性间苯二甲胺的最佳方案。研究结果表明,n(MXDA):n(壬基酚):n(甲醛)=1.4:1.2:0.8,反应温度100℃,反应时间4h时,合成的改性固化剂具有良好的工艺性能和水下粘接性能,同时环氧树脂浇铸体冲击性能优异,固化剂黏度4 705 mPa·s,水下粘接强度为7.54 MPa,冲击韧性达到24.7 kJ/m~2。     

环氧树脂腰果酚醛胺及腰果酚醛酰胺固化剂的合成及其性能研究

采用曼尼希反应合成了一类新的环氧树脂室温固化剂——腰果酚醛酰胺。重点研究了固化剂的合成机理及其胺值的控制方法。采用傅里叶红外光谱(FT-IR)表征了固化剂的结构。采用差示扫描量热仪(DSC)比较了腰果酚醛胺、腰果酚醛酰胺以及聚酰胺的固化动力学,并揭示了腰果酚醛酰胺的固化机理。分别以合成的腰果酚醛胺和腰果酚醛酰胺固化无溶剂环氧树脂涂料,测定涂层的机械力学性能、热力学性能以及防腐蚀性能,结果表明:相比聚酰胺和腰果酚醛胺固化剂,用腰果酚醛酰胺固化的涂膜具有优异的低温固化性、柔韧性、硬度以及防腐性能。     

曼尼希改性胺固化剂及在环氧胶中的应用研究

对聚环氧烷多胺环氧树脂固化剂进行了曼尼希反应改性。探究了曼尼希合成反应的原料配比对改性后的产物的胺值、黏度和粘接力学性能的影响,曼尼希改性胺中含水量对剪切强度的影响显著。改性后的胺类固化剂的80℃剪切强度和固化速率有明显提高,在80℃下它的剪切强度为14.92MPa,改性后体系的凝胶时间提高到5.9h。动态热分析仪测试的结果显示,曼尼希改性胺的固化体系的耐热性能好,玻璃化转变温度为81.64℃。     

我国曼尼希型环氧树脂固化剂的现状及发展预测

本文对曼尼希反应的国内外发展状况进行了简要介绍，系统地概括了曼尼希型改性胺固化剂的合成原理、工艺路线和工艺条件等制备技术及优点，对国内曼尼希型改性胺固化剂的现状进行了详细分析；对市场前景进行了分析预测，借鉴国外曼尼希型固化剂技术进步方向，针对国情，提出了国内2000年曼尼希型固化剂的制胜对策。     

曼尼希改性三乙烯四胺固化剂的合成及性能研究

对三乙烯四胺(TETA)环氧树脂固化剂进行了曼尼希(Mannich )改性及其固化性能的研究.实验结果表明:曼尼希固化剂最佳合成条件为n(TETA):n(苯酚):n(甲醛)=1.5:1:1,反应温度为80℃,反应时间4h,可制备出具有合适的黏度、适中的胺值以及游离酚含量小于5%的改性环氧树脂固化剂;其比未改性的三乙烯四胺有优异的物理化学性能和环保性能.固化剂与水不互容,不能与乳化环氧树脂互容,可用无水乙醇作为溶剂,得到良好的效果.     

环氧树脂固化用腰果酚型酚醛胺的制备及其固化动力学研究

以腰果酚、甲醛和二乙烯三胺为原料通过曼尼希反应合成了腰果酚醛胺固化剂,通过红外光谱和凝胶渗透色谱分别对其化学结构和相对分子质量进行了分析,并研究了腰果酚醛胺固化剂对环氧树脂的固化动力学。结果表明：制备的腰果酚醛胺固化剂的数均、重均相对分子质量均在 1 250左右,且相对分子质量分布较窄。通过将非等温 DSC曲线数据拟合 Kissinger方程、 Ozawa方程、 Crane方程,得到环氧树脂 /二乙烯三胺固化体系表观活化能为 71. 40 kJ/mol,环氧树脂 /腰果酚醛胺固化剂的表观活化能低于前者为 56. 72 kJ/mol,固化反应级数没有变化,均为 0. 93。因此,相比于传统固化剂二乙烯三胺,腰果酚型酚醛胺能使得环氧树脂在更低的温度下,更快地进行固化,符合研究预期结果。     

KJ-630高韧性环氧树脂固化剂的合成

采用多支链化合物改性苯酚(HBMP),通过曼尼希反应合成一种高韧性酚醛胺类环氧树脂固化剂。通过对其合成工艺、产物性能和固化性能的深入研究发现,该固化剂可大幅提高固化体系的韧性,获得了极佳的使用性能。     

腰果酚改性多乙烯多胺对环氧树脂固化物性能的影响

为了研究不同链长脂肪胺类固化剂二乙烯三胺(DETA)、三乙烯四胺(TETA)和四乙烯五胺(TEPA)经改性后对环氧树脂(EP)固化物性能的影响,利用曼尼希反应合成了3种改性固化剂。对改性后的固化剂进行胺值测定与红外(FT-IR)谱图分析,测试了固化物的力学性能和玻璃化转变温度(T)。结果表明,经过曼尼希反应改性后,3种固化剂的胺值分别降低了g55.4%、47.3%和46.2%;FT-IR表征显示,TETA、TEPA的改性反应程度强于DETA。固化物的拉伸、弯曲、压缩强度、拉伸弹性模量、伸长率等性能随着链长的增加先提高后降低,但抗剪强度与T随着链长的增加逐渐降低。g     

漆酚醛胺/环氧树脂体系固化动力学研究

采用固化动力学的方法研究漆酚醛胺/环氧树脂体系的固化行为,通过漆酚、二乙烯三胺、甲醛采用曼尼希反应制备漆酚醛胺还氧固化剂,使用非等温差示扫描量热分析(DSC)测定漆酚醛胺/环氧树脂体系固化过程的热量变化,使用n阶反应模型和自催化模型对实验数据进行拟合处理。结果表明,自催化反应模型能够较好的描述漆酚醛胺/环氧树脂体系的固化过程,确定了漆酚醛胺/环氧树脂体系自催化反应方程,为漆酚醛胺/环氧树脂体系固化工艺参数的优化提供理论指导。     

Ⅰ型水性环氧树脂涂料的研制

采用低分子量液体环氧树脂与非离子表面活性剂（BMJ）反应合成BMJ－环氧加成物,将表面活性链段引入到环氧树脂分子链中,然后经封端和成盐得到Ⅰ型水性环氧固化剂,研究了影响Ⅰ型水性环氧固化剂及其所配乳液涂料性能的因素,并对乳液的稳定性和固化速度,漆膜硬度等性能进行了评价。     

水性环氧树脂固化剂的研究进展

从水性环氧树脂固化剂的改性原理出发,介绍了现有制备胺类水性环氧树脂固化剂技术的三种改性方法,比较了酰胺化多胺、聚酰胺、多胺-环氧加成物等用作水性环氧树脂固化剂的优势与不足之处,并简单地归纳了水性环氧树脂固化剂研究与发展进程。     

环氧树脂室温固化用柔性固化剂的制备与性能研究

首先将聚醚多元醇和甲基丙烯酸甲酯(MMA)进行酯交换反应,然后利用多元胺与烯双键的加成反应原理,将多乙烯多胺与甲基丙烯酸酯进行反应,合成了含甲基丙烯酸聚醚多元醇酯柔性基团的新型环氧树脂室温固化剂。通过FT-IR等方法对产物结构进行表征,探讨并优化了各种反应条件,最后考察了该柔性固化剂对环氧树脂性能的影响。研究结果表明,柔性固化剂合成反应的优化条件是n(聚醚多元醇)∶n(MMA)为1∶5,n(催化剂)∶n(聚醚多元醇+MMA)为2∶100,n(聚醚多元醇酯)∶n(多乙烯多胺)为1∶2.0,反应时间为8h;在此条件下所得固化剂的产率和收率分别为96.3%和96.38%;改性固化剂/环氧树脂体系的凝胶时间仅为29min,拉伸剪切强度达到30MPa。     

Adhesive properties of cured epoxide resin containing the intermolecular compound of 2,4-diamino-6-vinyl-s-triazine and isocyanuric acid

The intermolecular compound of 2,4-diamino-6-vinyl-s-triazine and isocyanuric acid was synthesized, and the glass transition temperature and the adhesive properties of the cured epoxide resin containing the above compound were studied. Epoxide reacted with amino groups of 2,4-diamino-6-vinyl-s-triazine and isocyanuric acid at the curing conditions of 150 to 180°C for 60 min and formed the cured compounds. The infrared spectra showed that epoxide reacted with isocyanuric acid in the presence of imidazole compounds and converted to 2-oxazolidinone compound on the curing process. The glass transition temperatures of the cured compounds having isocyanurate and 2-oxazolidinone rings in their structures were higher than that of the epoxide resin cured with imidazole and rise as the curing temperature rises, but fall as 2-oxazolidinone ring content increases in their cured compounds. The tensile shear and peel strengths of the steel and steel bonded with the cured compounds and the cured epoxide resin were measured at 25 and 150°C. The adhesive strengths were improved due to isocyanurate and 2-oxazolidinone rings formed in their cured compounds.     

Hyperbranched polyamine: A promising curing agent for a vegetable oil-based poly(ester-amide) resin

A hyperbranched polyamine (HBPA) has been synthesized by a nucleophilic displacement polymerization of cyanuric chloride with an aromatic diamine, 4,4′-(1,3-phenylene diisopropylidene) bis-aniline by using an A₂ + B₃ approach with high yield (>78%). The synthesized polyamine was characterized by ¹H NMR, ¹³C NMR and FT-IR spectroscopic studies, X-ray diffraction study, elemental and thermogravimetric analyses and by measurement of solubility and solution viscosity. The polymer is soluble in polar solvents like DMAc, DMSO, DMF, THF, etc. but insoluble in water and non-polar solvents. The flame retardancy as measured by limiting oxygen index (LOI) test of the polymer indicates its self-extinguishing characteristic. This hyperbranched polyamine has been utilized as an effective curing agent for a Mesua ferrea L. seed oil-based poly(ester-amide) resin. This hyperbranched polyamine alone as well as with conventional metal catalyzed peroxide system is found to effectively cure the above resin at dose levels of 2.5–10 phr. The hyperbranched polyamine not only enhances the rate of crosslinking reaction but it also improves many desirable performance characteristics especially the thermostability, flame retardancy, hardness, impact strength, chemical resistance, etc. of the cured resin. Thus this study indicated that this hyperbranched polyamine acts as a promising curing agent for poly(ester-amide) resin.     

Cure kinetics of a high epoxide/hydroxyl group-ratio bisphenol a epoxy resin—anhydride system by infrared absorption spectroscopy

An infrared absorption spectroscopy study of the curing (gelation and postcure) kinetics of a high (4.7) epoxide/hydroxyl group-ratio diglycidyl ether of bisphenol A (DGEBA)–mixed anhydride epoxy resin system is reported. Peak assignments to molecular vibrational modes are given for the range 400–4000 cm^?1, and the optical density behavior of all peaks during reaction is discussed in detail. Chemical reaction was found to follow consecutive-step addition esterification and simultaneous addition etherification. Epoxide hydroxyl-group and carboxylic acid dimer hydrogen bonding was found to occur. The gelation phase of reaction is complex, exhibiting rapid initial hydroxyl–anhydride reactions followed by S-shaped kinetics approaching an incompletely reacted limit. Postcure exhibits functional group kinetic behavior similar to that occurring in low epoxide/hydroxyl group-ratio bisphenol A epoxy resin–phthalic anhydride systems and produces similar final chemical structures. The reaction behavior of low and high epoxide/hydroxyl group-ratio bisphenol A epoxy resin–anhydride systems arises from an hydroxyl group-limited inhomogeneous reaction mechanism involving bisphenol A epoxy resin molecular aggregates. The importance of free hydroxyl group content is discussed.     

水性环氧树脂乳化型固化剂固化特性研究

在多元胺中引入环氧树脂(EP),再通过成盐反应,合成出含仲胺盐结构、可乳化液体EP的固化剂;然后采用相反转法制备出稳定的水性EP乳液。结果表明:该固化剂在室温时具有一定的潜伏性(水性EP乳液室温储存期超过14 d),而在较高温度时具有快速固化的特点。仲胺盐的起始分解温度(Ti)约为113℃,当固化温度较低时,仲胺盐热分解反应难以进行,封闭的仲胺基与环氧基的固化反应难以发生,表现为成盐率越高,乳液凝胶时间越长;当固化温度>Ti时,仲胺盐快速热分解后释放出被封闭的活性仲胺基,乳液可快速固化,成盐率对乳液凝胶时间的影响不大。各固化膜均具有较低的吸水率(<3.1%),其耐水性和耐丙酮性能优良,但耐强酸、强碱性能较差且随固化剂成盐率提高而下降。     

水性聚氮酯的合成及其激活反应研究

聚乙二醇（PEG-1000）与甲基六氢苯酐（MHHPA）在催化剂XCT-cat81的存在下生成聚酯多元醇,再在催化剂XCT-cat57存在下,再与二苯基甲基4,4’-二异氰酸酯（MDI）反应生成聚氨酯预聚体,最后用苯酚封端制得水性聚氨酯。使用FTIR红外光谱仪分别对聚酯多元醇和水性聚氨酯进行了表征。使用大分子聚胺XCT-802及低分子二乙烯三胺（DETA）两种固化剂研究了水性聚氨酯封端基的激活反应,讨论了二种固化剂在不同固化温度与固化时间对水性聚氨酯木材黏结强度的影响。     

改性胺类环氧树脂固化剂的研制及其应用

本文介绍了用多元脂肪胺与酚类、醛缩合制成一种改性胺类环氧树脂固化剂的方法,并讨论了原料的选择、工艺条件的确定和应用。