共查询到19条相似文献,搜索用时 78 毫秒
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含呋喃环系西佛碱型大环化合物的合成 总被引:3,自引:0,他引:3
利用 Mn~(++)和 Ba~(++)作为模板离子,合成了一类新型的含呋喃环系西佛碱型大环化合物L~1 和配合物 L~2 Ba(ClO_4)_2、L~3 Ba(ClO_4)_2 和 L~4 Ba(ClO_4)_2.L~2~L~4 的 Ba~(++)配合物经与 Na_2 SO_4 水溶液反应解络,得到自由配体 L~2、L~3 和 L~4。配体 L~2 和 L~3 分别与 Sr~(++)作用,得到配合物 L~2 Sr(ClO_4)_2 和 L~3 Sr(ClO_4)_2。上述大环配体和各种配合物均经元素分析、IR、~1HNMR、MS 等证实了它们的结构和组成。 相似文献
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直接酯化法合成聚2,5-呋喃二甲酸乙二酯 总被引:1,自引:3,他引:1
以2,5-呋喃二甲酸(FDCA)和乙二醇(EG)为原料,草酸亚锡为催化剂,采用直接酯化法制备了聚2,5-呋喃二甲酸乙二酯(PEF)。考察了酯化反应、酯化产物、缩聚反应及缩聚产物的影响因素,结果表明,草酸亚锡在该体系中既可催化酯化反应又可催化缩聚反应,当n(FDCA)∶n(EG)=1∶1.6、草酸亚锡摩尔分数为0.1%、酯化温度为210℃、缩聚温度为240℃、缩聚反应时间为480 min、磷酸三甲酯摩尔分数为0.03%时,酯化程度最高(酯化产物的酸值在94%以上),缩聚产物相对分子量最高(比浓粘度达到1.29 dL/g),端羧基含量最低(34.3 mol/t);采用FTIR和1H NMR对目标产物的结构进行了表征。 相似文献
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提供了一种合成噻吩基和呋喃基四硫富有瓦烯(TTF)的方法,并用其合成了3种未见文献报道的噻吩基TTF(Ⅶa,Ⅷb,Ⅶc)和2种呋喃基TTF(Ⅶd1,Ⅶd2)研究这些化合物的循环伏安行为及有关电化学性质,制得了一种Ⅶb与TCNQ反应生成的电荷转移络合物,讨论了噻吩基TTF和呋喃基TTF在产物构型和电化学性质方面的差别。 相似文献
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以对苯二酚及对氟苯甲腈为原料, 合成了芳香二羧酸单体1,4-二(4-羧基苯氧基)苯(BCPOB-COOH), 再经磺化反应合成了磺化芳香二羧酸单体1,4-二(4-羧基苯氧基)苯-2-磺酸钠(BCPOBS-Na). 另外, 以芳香二胺单体4,4'-二氨基二苯醚(ODA)为原料, 合成了磺化芳香二胺单体4,4'-二氨基二苯醚-2,2'-二磺酸(ODADS). 以N-甲基-2-吡咯烷酮(NMP)为溶剂、 亚磷酸三苯酯(TPP)与吡啶(Py)为缩合剂, 氯化钙或氯化锂或二者的组合为催化剂, 通过Yamazaki-Higashi直接缩聚, 使芳香二羧酸和芳香二胺中的磺化单体与非磺化单体反应, 制得了两种磺化芳香聚酰胺(Sulfonated polyamide, SPA). 通过红外光谱、 核磁共振波谱及热重分析等手段对聚合物的结构及性能进行了表征与分析, 并研究了聚合物的特性黏度、 溶解性、 成膜性及聚合物薄膜的力学性能等. 结果表明, 通过Yamazaki-Higashi直接缩聚制备的2种磺化芳香聚酰胺在极性非质子性溶剂中具有优良的溶解性能、 较高的耐热性能及优异的力学性能. 相似文献
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Polyamides represent a very important class of polymers for a wide range of applications. After establishing in the 1930s with Nylon and Perlon, their impact on many branches has been continuously growing. In the context of developing sustainable polymers from renewable resources, many polyamides have meanwhile been described, which are based on natural building blocks. In addition to their sustainability, these biobased starting materials can provide special structural features to the resulting polymers and their properties, e.g., side groups, functionalities, or stereoinformation. While some biopolyamides are known for decades and well established (e.g., PA‐11, Rilsan), many other promising candidates have been described in fundamental research studies, which have high potential but whose capability—especially for large scale and/or high‐performance materials—will have to be proved in the future. Other candidates are very interesting from a scientific point of view, but with less potential for a market establishment due to price and/or feasibility reasons. This article aims at collating the recent developments in the field of biopolyamides and elucidating their properties and potential for different applications.
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超支化聚芳酰胺的合成 总被引:1,自引:0,他引:1
由3,5-二硝基苯甲酰氯和邻氨基苯甲酸合成了AB2型单体2-(3,5-二氨基苯甲酰氨基)苯甲酸。该单体进行自缩聚反应,合成了新型超支化聚酰胺(a),将其与酰氯反应,得到了7种封端的超支化聚合物(b~h)。用FT-IR1、H NMR、GPC、DSC测试技术对超支化聚合物进行了表征。封端改性后,聚酰胺的溶解性均得到了提高,聚合物的重均分子量(Mw)为3.36~3.96 kg/mol,特性粘度(ηinh)为0.061~0.078 dL/g,聚合物玻璃化转变温度(Tg)为56~185℃,随封端剂脂肪链增长而降低,随封端剂极性增加而升高。 相似文献
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Yuehua Zhang John C. Tebby John W. Wheeler 《Journal of polymer science. Part A, Polymer chemistry》1997,35(3):493-497
Four novel polyamides have been prepared in high yields by the polycondensation reactions of bis(3-carboxyphenyl)- and bis(4-carboxyphenyl)phenylphosphine oxide with 3,3′- and 4,4′-diaminodiphenylsulfone. The thermal properties of these materials were studied using differential scanning calorimetry and thermogravimetric analysis. It was found that the presence of both phosphine oxide and sulfonyl groups within the polymer backbone brought about remarkable modifications in the thermal behavior. Glass transition temperatures 40–50°C lower than those of conventional polyamides i.e., in the range 170–200°C, were recorded. However, we observed greater thermooxidative stability (5% weight loss at >410°C) and high char yield upon prolonged heating at 800°C (20–34%). Also, good solubility in polar aprotic solvents was observed for all polyamides together with some solubility in aqueous solvent mixtures, e.g. tetrahydrofuran/water (95:5). © 1997 John Wiley & Sons, Inc. 相似文献
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Yuehua Zhang John C. Tebby John W. Wheeler 《Journal of polymer science. Part A, Polymer chemistry》1996,34(8):1561-1566
Five novel polyamides incorporating phosphine oxide groups have been synthesized by the condensation reaction of bis(4-carboxyphenyl)phenylphosphine oxide with a series of aromatic diamines. The thermal properties of these polymers were investigated by differential scanning calorimetry and thermogravimetric analysis. Glass transition temperatures in the 225–254°C range were recorded, together with good thermooxidative stability (5% weight loss occurring at >420°C) and high char yield upon prolonged heating at 650–800°C (24–50%). Also, good solubility in aprotic polar solvents was observed for all polyamides synthesized. © 1996 John Wiley & Sons, Inc. 相似文献
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以可再生资源2,5-呋喃二甲酸(FDCA)和1,8-辛二醇(1,8-ODO)为原料,钛酸四丁酯为催化剂,采用直接酯化法制得聚2,5-呋喃二甲酸1,8-辛二酯(1,8-POF)。 考察了原料配比、催化剂用量、酯化温度、缩聚温度及缩聚时间对聚合反应的影响,结果表明,当n(FDCA)∶n(1,8-ODO)=1∶1.2,钛酸四丁酯摩尔分数为0.3%,酯化温度为240 ℃,缩聚温度为260 ℃,缩聚时间为300 min时,缩聚产物的比浓粘度最高(2.1 dL/g),端羧基含量最低(5.8 mol/t)。 与乙二醇相比,采用1,8-辛二醇为单体降低了酸醇的摩尔比,减少了醇的消耗,同时得到了较高分子量的聚合物。 气质联用仪对酯化馏出液和缩聚产物真空抽出物进行了分析,结果表明,酯化馏出液的主要成分是水,并含有少量的1,8-ODO;缩聚产物真空抽出物的组成为环己酮(56%)、顺式-3-辛烯醇(18%)、4-甲基-3-戊烯-2-酮(17%)和4-羟基-4-甲基-2-戊酮(9%)。 相似文献
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长链脂肪族二元酸一般是指含有10个或以上碳原子的饱和直链二元酸,其两端带有羧基官能团,可用于合成香料、特种尼龙工程塑料、热熔胶、涂料、增塑剂、高级润滑油等众多化工产品;由于其链段中含有长烷烃链段,具有优于短链二元酸的性质,使得相应的合成材料具有优越的性能,因此广泛应用于化工、轻工、国防、汽车工业、工程材料等领域;同时,还可用于开发新的聚合物产品。长链脂肪族二元酸在自然界中不单独存在,目前工业上主要通过化学合成法和生物发酵法生产。本文主要对长链脂肪族二元酸的合成方法进行综述,包括传统有机合成、生物技术转化、烯烃复分解、异构化-氢氧羰基化及聚乙烯端基功能化等,并简要概述长链脂肪族二元酸在缩聚反应(聚酯和聚酰胺)中的应用。最后,对合成方法待解决的问题进行了总结,并对未来发展方向进行了展望。 相似文献