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1.
二元酸单甲酯;环氧化合物;碱水显影阻焊油墨研究—羧基与环氧基的反应  相似文献   

2.
利用腰果酚缩水甘油醚与经酸酐酸化后的酚醛环氧丙烯酸酯反应,得到改性碱溶性酚醛环氧丙烯酸酯树脂,并将其应用到感光型阻焊油墨中。实验通过红外以及核磁氢谱证明了目标产物的成功合成。该改性树脂所制得的涂层具有优异的感光性、耐热性以及力学强度,同时柔韧性得到提升。将其应用到感光型阻焊油墨中,与用未改性碱溶性酚醛环氧丙烯酸酯树脂制得的油墨相比,在保持良好显影性和感光性的同时,解析度由140μm提高到了85μm,显影线条的最小侧蚀由37.1μm降低到10.4μm,展现了优异的抗蚀刻能力。  相似文献   

3.
本文介绍了PCB制造过程中所用阻焊油墨的研究现状及其发展趋势,重点介绍了可喷墨打印阻焊油墨、柔性电路板用阻焊油墨、水溶性碱显影感光阻焊油墨和LED封装用白色阻焊油墨的研究现状及趋势。  相似文献   

4.
树脂;多元羧酸酐;光固化;碱显影;羧基化环氧丙烯酸酯合成及在光成像阻焊油墨中的应用  相似文献   

5.
紫外线(Ultra Violet, UV)固化喷墨打印技术将打印技术与UV固化系统结合,集成了喷墨打印技术无接触、操作简单、低成本及UV固化后无溶剂残留、环保的特点,广泛应用于印制电路板中阻焊层的制备,陶瓷材料、盲文及电子器件的制备,纺织品制造,木材表面的修饰或保护等领域。UV固化喷墨打印墨水是该技术的关键原料,它主要由UV单体、UV预聚物、光引发剂、添加剂及助剂等组成,并根据不同应用要求添加功能材料,如金属、金属氧化物、碳纳米材料或量子点等。UV固化喷墨打印技术用于阻焊层制备时的关键在于墨水固化后形成的涂层与基材粘附力的调控,涂层与基材结合既要保证阻焊的效果,又要在阻焊后易于分离并去除。了解UV固化喷墨打印技术在应用中的各种关键因素及对策,对于其进一步推广应用具有重要意义。  相似文献   

6.
以有机硅改性丙烯酸环氧单酯为树脂配制了一系列紫外光-热混杂固化体系.通过FTIR表征了光-热固化过程双键和环氧特征吸收峰的变化.研究了不同的稀释剂对光固化和光-热混杂固化膜的凝胶率、吸水率、表面水接触角等性能的影响,并用能谱仪(EDS)测试了固化膜表面硅元素的含量.结果表明:光固化膜的凝胶率低于86.5%,而光-热混杂固化膜的凝胶率在97.0%左右.与丙烯酸环氧单酯光-热固化体系相比,有机硅改性丙烯酸环氧单酯光-热固化膜的表面水接触角有显著提高,由62.53°提高到99.27°,EDS测试也表明有机硅有富集于固化膜表面的特性.  相似文献   

7.
合成了含环氧基团的可交联的甲基丙烯酸甲酯和甲基丙烯酸环氧丙酯的共聚物[Poly(MMA-co-GMA)],通过FTIR,NMR,GPC,DSC和AFM等技术对其进行了表征. 结果表明,所合成的聚合物材料具有较好的成膜性; 通过热固化使引入的环氧基团开环交联,该聚合物的玻璃化转变温度(Tg)比固化前提高了24 K,同时有效地降低了聚合物的双折射率. 用Poly(MMA-co-GMA)作为包层材料,双酚A型环氧化合物作为高折射率材料, 将其引入到包层材料中形成芯层材料的折射率在波长1.55 μm处可调,其范围是1.483~1.588. 采用旋涂、 铝掩膜和氧反应离子刻蚀的方法(RIE)制得了阵列式光波导. 测试结果表明,制作的波导在1.55 μm处实现了光的单模传输,光损小于3.0 dB/cm.   相似文献   

8.
为了获得高分辨率和耐侧蚀性能优异的阻焊油墨,本文利用叔碳酸缩水甘油酯(E10p)对碱溶性酚醛环氧丙烯酸酯进行改性,并将其应用到阻焊油墨体系。实验结果表明,该改性树脂具有优异的感光性,同时涂层性能测试表明该树脂具有优异的耐热性及柔韧性。与未改性树脂相比,该树脂所制备的阻焊油墨分辨率由75 μm线距提高到50 μm,侧蚀由37.5 μm降低到24.5 μm,表现出了更高的分辨率及更优的耐侧蚀性。  相似文献   

9.
通过对比研究硫磺固化液体丁腈橡胶、液体丁腈橡胶/苯基缩水甘油醚、液体丁腈橡胶/邻烯丙基苯基缩水甘油醚3个体系的固化反应,推测了硫磺/含双键橡胶/环氧树脂体系的反应机理.采用示差扫描量热(DSC)法、红外光谱(FTIR)法、X射线光电子能谱(XPS)法、动态力学分析(DMA)法研究了固化反应放热,双键和环氧基团随反应时间的变化,固化产物中苯环、氧元素、网络结构与模型化合物结构的关系.实验结果表明,硫磺/液体丁腈橡胶体系是一步反应、硫磺/液体丁腈橡胶/环氧化合物体系是两步反应,且丁腈橡胶与环氧化合物之间有化学键键接;液体丁腈橡胶/硫磺、液体丁腈橡胶/苯基缩水甘油醚/硫磺、液体丁腈橡胶/邻烯丙基苯基缩水甘油醚/硫磺3个体系的玻璃化转变温度依次升高,储能模量、交联密度依次降低.在此基础上提出液体橡胶与环氧化合物的固化反应机理为:硫磺裂解生成硫自由基,一方面部分硫自由基与体系中的双键发生加成反应,另一方面硫自由基与烯丙基α位的活泼氢反应生成巯基,巯基引发环氧基团发生开环反应,体系内的自由基间相互偶合交联.  相似文献   

10.
为了制备X光可显影且可以体温固化的聚氨酯,合成了N,N'-双(1,3-二羟基丙基)-2,3,5,6-四碘对苯二甲酰胺(BDTIP)含碘四元醇,将其作为聚氨酯固化的交联剂和X光显影剂,与聚氨酯预聚物混合反应得到一种新的可用于人工髓核假体的材料.利用红外光谱监测BDTIP的反应程度;利用X射线对不同BDTIP含量的聚氨酯材料的显影效果进行评定;利用噻唑蓝(MTT)比色法测试材料细胞毒性,并对具有不同碘含量聚氨酯材料的力学性能进行了对比研究.结果表明,碘的加入对聚氨酯的显影效果有很好的促进作用,较低碘含量(0.2 wt%)的聚氨酯材料即有较好的X光显影效果,而且此时聚氨酯依然保持较好的力学性能;MTT法测试表明含BDTIP的聚氨酯材料不具有细胞毒性.  相似文献   

11.
Alkylpinacol phosphonates were prepared by rhodium-catalyzed olefin hydrophosphorylation, and attempted alpha-deprotonation of the pinacol derived alkyl phosphonates resulted in ring cleavage. The propensity of the alkylpinacol phosphonates to undergo ring opening was exploited to prepare phosphonic acid monomethyl esters in high yield by transesterification in acidulated methanol. Esterification and alkylation with aldehydes or ketones gave beta-hydroxy mixed phosphonate esters. tert-Butyl and benzylic phosphonate ester protective groups were introduced to improve the efficiency and functional group compatibility of beta-hydroxy phosphonate saponification. The beta-hydroxy phosphonic acid monomethyl esters were dehydrated with diisopropylcarbodiimide, which gave oxaphosphetane intermediates that collapse to an olefin. The overall reaction sequence complements the arsenal of Horner-Wadsworth-Emmons-type coupling reactions.  相似文献   

12.
Trans-alkyl cyclohexane formic acid phenol ester compounds are synthesised by reaction of trans-cyclohexane formic acid and phenols. This process also produces many harmful cis-alkyl cyclohexane formic acid phenol ester compounds that are harmful to the environment. Using p-toluenesulphonic acid as the catalyst in this experiment, these cis compounds were transformed to their trans form. The yields of trans-alkyl cyclohexane formic acid phenol ester compounds were more than 70%, which was significantly higher when compared to the yields of 40–60% obtained using the control method. The effects of catalyst, reaction time and reaction temperature on cis–trans transformation were investigated. The possible mechanism of cis–trans transformation has been discussed in this report.  相似文献   

13.
The first catalytic asymmetric direct Mannich reaction of malonates and beta-keto esters has been developed. Malonates react with an activated N-tosyl-alpha-imino ester catalyzed by chiral tert-butyl-bisoxazoline/Cu(OTf)(2) to give the Mannich adducts in high yields and with up to 96% ee. These reactions create a chiral quaternary carbon center and it is demonstrated that this new direct Mannich reactions provides for example a new synthetic procedure for the formation of optically active beta-carboxylic ester alpha-amino acid derivatives. A series of different beta-keto esters with various ester substituents has been screened as substrates for the catalytic asymmetric direct Mannich reaction and it was found that the best results in terms of yield, diastereo- and enantioselectivity were obtained when tert-butyl esters of beta-keto esters were used as the substrate. The reaction of different beta-keto tert-butyl esters with the N-tosyl-alpha-imino ester gave the Mannich adducts in high yields, diastereo- and enantioselectivities (up to 95% ee) in the presence of chiral tert-butyl-bisoxazoline/Cu(OTf)(2) as the catalyst. To expand the synthetic utility of this direct Mannich reaction a diastereoselective decarboxylation reaction was developed for the Mannich adducts leading to a new synthetic approach to attractive optically active beta-keto alpha-amino acid derivatives. Based on the stereochemical outcome of the reactions, various approaches of the N-tosyl-alpha-imino ester to the chiral bisoxazoline/Cu(II)-substrate intermediate are discussed.  相似文献   

14.
Vinylversatate-10 (VV10)1 has successfully been used to synthesise a large number of lower vinyl esters by transvinylation in presence of mercuric acetate and sulfuric acid. The synthesis of vinylhalo esters proceeds with more difficulty. It has been observed that neither Hg(OAc)2 nor H2SO4 alone is capable of initiating the transvinylation. Furthermore, it has been found that a molar ratio 2:1 of VV10 to carboxylic acid is sufficient to drive the reaction to the right by continuous distillation of the vinyl ester formed, and as a result a high yield of vinyl ester is obtained. A mechanism for this reaction and for the formation of side products has been proposed.  相似文献   

15.
An efficient, diastereoselective synthesis of substituted and unsubstituted 2,3,4,5‐tetrahydro‐1H‐1‐benzazepine‐5‐carboxylic esters has been developed based on the tandem reduction‐reductive amination reac tion. Catalytic hydrogenation of a series of 2‐(2‐nitrophenyl)‐5‐oxoalkanoic esters initiates a reaction sequence involving (1) reduction of the aromatic nitro group, (2) condensation of the N‐hydroxylamino (or amino) nitrogen with the side chain carbonyl, and (3) reduction of the seven‐membered cyclic imine. Cyclizations that produce 2‐alkyl‐2,3,4,5‐tetrahydro‐1H‐1‐benzazepine‐5‐carboxylic esters are diastereose lective for the product having the C2 alkyl and the C5 ester groups cis. In these reactions, the transannular ester group exerts a strong stereodirecting effect on the reduction of the cyclic imine intermediate, though not as strong as that observed in previous closures of 2‐alkyl‐1,2,3,4‐tetrahydroquinoline‐4‐carboxylic esters. This decrease in diastereoselectivity is attributed to (1) the greater distance between the ester and the imine double bond and (2) the increased conformational mobility of the larger ring, both of which diminish the stereodirecting effect of the ester. Finally, formation of the seven‐membered ring is sufficiently slow that reaction with the side chain ester group competes with heterocycle formation in several of the reactions.  相似文献   

16.
The use of protected amino acid chlorides for peptide coupling reactions has long been avoided due to the extensive racemization that commonly occurs during either the acid chloride formation or the coupling reaction itself. Conditions are described which allow N-trifluoroacetyl-protected amino acid chlorides to be generated in high purity and with high retention of stereochemical integrity. Control of temperature is the predominant factor in controlling racemization, and rapid formation of acid chlorides under low temperature can be conveniently achieved using Vilsmeier reagent. Stereochemical integrity is further maintained when coupling of N-trifluoroacetyl acid chlorides is carried out with amino acid esters under Schotten-Baumann conditions using specific controls on pH, temperature, and agitation. Second order rate constants for coupling and the azlactone formation associated with racemization were measured to be 4260 and 3.6 L/mol s, respectively. This high rate differential allows for the reaction to be run with a minimum excess of amine ester, and makes it suitable for continuous processing. The applicability of the preferred coupling conditions to a range of amino acid couplings is described.  相似文献   

17.
Addition of highly stabilized ester nucleophiles to 1,2-dioxines affords good to high yields of gamma-lactones with high diastereoselectivity. Heterolytic or homolytic cleavage of the 1,2-dioxines under appropriate conditions generates the key reactive cis gamma-hydroxy enones, which ultimately afford the observed gamma-lactones. Diastereoselectivity is installed as a result of anti 1,4-addition by the ester enolate to the cis enones followed by intramolecular cyclization. The reaction is tolerant of a range of substitution patterns on the 1,2-dioxine while a broad range of esters are also accommodated. In addition to the synthesis of racemic gamma-lactones, highly enantioenriched gamma-lactones can also be synthesized when chiral cobalt(II) catalysts are employed for the initial homolytic ring-opening of the 1,2-dioxine.  相似文献   

18.
The selective fluorolactonization was achieved by treatment of cis-5-norbornene-2,3-endo-dicarboxylic acid or its monomethyl and dimethyl esters with F-TEDA-BF4 or XeF2. The reactions of 5-norbornene-endo-2-carboxylic acid and its monomethyl ester with F-TEDA-BF4 or XeF2 proceed in a non-selective manner to give fluorolactonization, addition and rearrangement products. The basic factor responsible for selectivity of the fluorolactonization is the presence of two endo-oriented carboxyl groups in the substrate molecule. The electrophilicity and type of the fluorinating agent is of secondary importance in this regard. It is postulated that the fluorolactonization of norbornenecarboxylic acids and their methyl esters with F-TEDA-BF4 or XeF2 is realized mainly via “open” fluoronorbornyl carbocation intermediates which in the reaction with XeF2 are postulated as the tight ion pairs.  相似文献   

19.
双吡唑酮羧酸酯螯合剂的合成   总被引:2,自引:0,他引:2  
毕韵梅  何森泉 《有机化学》1991,11(3):299-302
1909年,Johannes 用丁、戊、已二酰丙二酸二乙酯与苯肼反应合成了相应的双吡唑酮羧酸酯(3)(n=2,3,4)。近年来,吡唑酮类化合物在金属离了的分析和分离工作中得到了广泛的应用。本文报道用类似于 Johannes 的方法,由  相似文献   

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