催化氧化环己烯清洁合成己二酸

在无相转移催化剂和有机溶剂存在条件下,将自制的钨酸用于H2O2氧化环己烯合成己二酸的清洁工艺中.通过单因素实验确定合成己二酸的较佳工艺条件为:n(钨酸)=2.5 mmol,n(H2O2)∶ n(环己烯)=4.9∶ 1,回流反应6 h,反应开始时加入25 mL 30%H2O2和10 mL环己烯,反应1 h后再加入25 mL 30%H2O2,己二酸产率可达74.2%.含钨酸的滤液经浓缩后可重复使用6次,己二酸的产率无明显下降.     

植物甾醇已二酸单酯的合成与固体纳米脂质粒的制备

以植物甾醇、己二酸为原料,二甲苯为溶剂,对甲苯磺酸为催化剂合成了植物甾醇己二酸单酯,并通过FT–IR、13C NMR、HPLC等分析手段证实了产物的结构;以植物甾醇己二酸单酯为原料,制备出固体纳米脂质粒。     

增塑剂己二酸二异辛酯合成研究进展

较全面的介绍了己二酸二异辛酯合成中的催化剂体系,包括无机酸、有机酸、固体酸、钛酸酯类以及其他催化方法等,并对其发展前景进行了展望。     

磷钨酸催化合成己二酸二丁酯

以Keggin型磷钨酸为催化剂、甲苯为带水剂,采用均匀设计,确定合成己二酸二丁酯的最佳工艺条件为:n(正丁醇)∶n(己二酸)=3.3,m(磷钨酸)∶m(己二酸)=1.5∶100,w(甲苯)=24%,反应时间2 h.在此条件下,酯化率可达99.45%.     

磷钨酸催化合成己二酸二丁酯

以Keggin型磷钨酸为催化剂、甲苯为带水剂,采用均匀设计,确定合成己二酸二丁酯的最佳工艺条件为：n（正丁醇）∶n（己二酸）=3.3,m（磷钨酸）∶m（己二酸）=1.5∶100,w（甲苯）=24%,反应时间2 h.在此条件下,酯化率可达99.45%.     

塑化剂己二酸二丁酯的合成现状和发展

本文阐述了增塑剂己二酸二丁酯的合成方法现状和发展,利用六水合氯化铁作催化剂来催化己二酸和正丁醇发生酯化反应。有效地避免了以传统的硫酸作为催化剂来合成己二酸二丁酯产生的环境污染。     

代谢工程改造大肠杆菌利用脂肪酸合成己二酸

己二酸作为生产尼龙、化纤和工程塑料等聚合物的单体,在食品、医药、塑料和化工行业具有广泛的应用。目前,己二酸的生物合成主要利用可食用原料,碳原子损失较多,造成己二酸产率较低。为解决上述问题,设计和重构以脂肪酸为原料的己二酸合成新路径,提高己二酸的理论得率;其次,强化本源的β-氧化路径和引入异源的ω-氧化路径;增强细胞对脂肪酸的利用能力;再次,借助系统代谢工程策略,进一步优化己二酸合成路径。最后,经发酵条件优化,最优工程菌Escherichia coli AA0304能够产生1.32 g/L己二酸。上述研究结果为利用废弃脂肪酸类化合物生产高价值化学品奠定了良好的基础。     

己二酸交联淀粉的制备及理化性质研究

通过单因素试验和正交试验,研究己二酸交联淀粉的制备方法,测定己二酸交联淀粉的的多个理化性质.试验结果表明:经过己二酸交联改性的淀粉抗凝沉性减弱,冻融稳定性提高,膨胀度和溶解度降低.以己二酸为交联剂制备交联淀粉的最佳工艺条件为反应体系pH值9,反应温度50℃,反应时间1 h,交联剂比例为0.4&.     

PAE-酚醛树脂鞣剂的研制

以己二酸,二乙烯三胺、环氧氯丙烷、苯酚、甲醛为原料,合成了一种新型的毛皮鞣剂.本文主要讨论了该鞣剂的合成方法及合成中各种影响,应用试验结果表明:该鞣剂可以直接用做主鞣剂,对毛皮具有一定的保毛性及助染性,并且鞣制的毛皮柔软,毛色光亮.     

酿酒酵母异源合成己二酸

以酿酒酵母(Saccharomyces cerevisiae)为底盘生物,将来源于嗜热菌Thermobifida fusca B6中的己二酸逆降解途径基因搭配不同的酿酒酵母组成型启动子和终止子,构建在3个穿梭质粒上,并导入宿主细胞,成功实现了己二酸的异源合成。将AA-1菌株在YPD培养基中发酵,得到3. 39 mg/L己二酸,是同一宿主中已报道的最高值。同时,敲除了酿酒酵母TCA循环关键基因LSC1,但未能使己二酸产量提高。通过发酵实验,研究了生物量、副产物乙醇与己二酸产量的联系;并通过改变初始碳源浓度对乙醇和己二酸产量进行了研究,为进一步提高己二酸产率、降低酿酒酵母葡萄糖效应提供了参考依据。     

生物合成己二酸的代谢工程研究进展

己二酸是一种重要的大宗化学品,主要用于合成尼龙和聚氨酯泡沫塑料,市场需求巨大,其高效生物合成至今还未实现。本文概括了酿酒酵母中构建和优化新的己二酸合成途径研究进展。首先,通过体内及体外活性测试,对催化每一步反应的酶进行筛选,构建初步的代谢途径。利用组学分析诊断和定位生物合成途径的瓶颈。对于途径中的限速酶采用蛋白质工程手段进行改造。其次,利用合成生物学和代谢工程手段优化代谢途径。优化手段具体包括:通过模块化优化,平衡各个基因之间的表达;利用蛋白支架,构建酶反应的流水线,减少中间产物的扩散,提高反应效率;通过RNA干扰技术抑制竞争代谢途径的流量,提高目标代谢途径的通量。最后,利用CRISPR/Cas9及全局转录机器工程(gTME)等最新技术进行基因组编辑、重排转录网络,最终获得己二酸的高产菌株及适用于高效生产其他芳香族化合物的底盘酵母菌株。     

Structural characterisation of β‐cyclodextrin crosslinked by adipic acid

This study was conducted to investigate the structural characterisation of β‐cyclodextrin (β‐CD) crosslinked by adipic acid. β‐CD was treated with different concentrations (0%, 5%, 10% and 15%, w/v) of adipic acid. Different instruments, such as scanning electron microsope (SEM), Fourier‐transform infrared (FT‐IR) spectroscopy and ¹H and ¹³C nuclear magnetic resonance (NMR) spectra were used to find out chemical structure in the crosslinked β‐CD. SEM analysis suggested that crosslinking β‐CD with 15% adipic acid changed the original morphology and considerably increased the particle size of the raw material. FT‐IR spectroscopy data showed that an intensive absorption band at 1706 cm^?1 was present in the β‐CD samples treated with 10% and 15% adipic acid, indicating a crosslinking between hydroxyl groups of β‐CD and carboxyl groups of adipic acid. NMR spectra revealed that the ester linkages between hydroxyl groups of β‐CD and carboxyl groups of adipic acid were formed after crosslinking of β‐CD with adipic acid.     

新型聚酰胺纤维亲水整理剂PPAG合成及其应用研究

采用己二酸(AA)、己二胺(HDA)和双端羧基聚乙二醇(CT-PEG)为原料,通过缩聚反应,合成具有一定分子质量的聚酰胺聚酯聚醚嵌段共聚型亲水整理剂PPAG,并应用于聚酰胺纤维亲水整理.研究了反应物料配比、缩聚温度和缩聚时间对整理织物润湿时间的影响,优化了合成工艺条件;采用FTIR-ATR、GPC及TG对整理剂进行了结构表征和热性能测试;测定整理剂整理织物亲水性能及其耐洗性能,并与市场上其他亲水整理剂进行比较.结果表明:整理剂PPAG的优化合成条件为:n(己二酸)∶n(己二胺)∶n(双端羧基聚乙二醇)=1.0∶3∶1,缩聚温度为240℃,反应时间为2.5 h.整理织物润湿时间为6.3 s,洗涤20次,其整理织物润湿时间小于10 s,具有较好的亲水性和耐洗性,已达到国外同类产品水平.与水溶性聚醚硅油亲水整理剂相比,整理剂PPAG亲水性差,但耐洗性具有一定的优势.     

己二酸市场状况及发展趋势

本文详细阐述了己二酸的用途、价格趋势、市场状况以及今后一段时期内己二酸新建拟建情况.分析认为，国内己二酸产品在未来的几年内将会达到供需平衡。     

Storage of Structured Beef Steakettes Produced with Algin/Calcium/Adipic Acid Gel

Binding properties and shelf-life characteristics of solid-muscle structured beef produced with algin/calcium/adipic acid binding gel were evaluated. Juncture binding strength and surface discoloration were not affected by refrigerated storage of meat blocks up to 35 days. Fresh steakettes had stronger muscle junctures than frozen steakettes in both raw and cooked forms. Rancidity development was greatest in steakettes stored in oxygen permeable packages. Results indicated structured meat products bound with algin/calcium/adipic acid gel maintained integrity following extended refrigerated and/or frozen storage.     

过氧化尿素及其在纸浆漂白中的应用

介绍了过氧化尿素比其他过氧化物所具有的优点及其制备方法，并举例说明了过氧化尿素在纸浆清洁漂白生产中的优点，指出作为新型无氯漂白剂的过氧化尿素具有广阔的应用前景。     

丁酮的Baeyer-Villiger氧化合成乙酸乙酯的研究

本试验以三氟乙酸酐和30％过氧化氢为原料制备过氧三氟乙酸,通过Baeyer-Villiger反应将丁酮氧化成乙酸乙酯.在温度为40℃,三氟乙酸酐用量为40 mmol,过氧化氢用量为25 mmol,反应时间为3h以及不加缓冲剂的条件下氧化15 mmol丁酮时取得较好效果,丁酮转化率为96.02％,产物乙酸乙酯的得率为48...     

Determination of polyadipates migrating from lid gaskets of glass jars. Hydrolysis to adipic acid and measurement by LC–MS/MS

Polyadipate plasticizers can be present in the polyvinylchloride (PVC) gaskets used to seal the lids of glass jars. As the gaskets can come into direct contact with the foodstuffs inside the jar, the potential exists for polyadipate migration into the food. The procedure and performance characteristics of a test method for the analysis of polyadipates in food simulants (3% aqueous acetic acid and 10% aqueous ethanol) and the volatile test media used in substitute fat tests (isooctane and 95% aqueous ethanol) are described. The PVC gaskets were exposed to the food simulants or their substitutes under standard test conditions. Studies were initially carried out using direct measurement of the polyadipate oligomers by liquid chromatography with time-of-flight mass spectrometric detection (LC-TOF-MS) but this was not practical due to the number of peaks detected. Instead, the migrating polyadipates were hydrolysed to adipic acid and measured by liquid chromatography with tandem mass spectrometric detection (LC–MS/MS). The amount of polyadipate that this measurement of adipic acid represents was then calculated. Method performance was assessed by analysis of gaskets from two types of jar lids by single-laboratory validation. Linearity, sensitivity, repeatability, intermediate reproducibility and recovery were determined to be suitable for checking compliance with the 30 mg/kg specific migration limits for polyesters of 1,2-propane diol and/or 1,3- and/or 1,4-butanediol and/or polypropylene-glycol with adipic acid, which may be end-capped with acetic acid or fatty acids C₁₂–C₁₈ or n-octanol and/or n-decanol. The method was found to be much quicker than previous methods involving extraction, clean-up, hydrolysis, esterification, derivatisation and GC measurement, consequently saving time and money.     

乳液催化大豆油的环氧化

以磷钨酸为催化剂,考察了乳化剂季铵盐的种类对合成环氧大豆油的影响。其中,十六烷基三甲基氯化铵的效果相对较好。结合磷钨酸的催化性能与十六烷基三甲基氯化铵的乳化性能,实现大豆油的高效环氧化,且易溶于反应体系的磷钨酸与十六烷基三甲基氯化铵可原位生成不溶的磷钨酸季铵盐固体,易于与产物分离。此外,也考察了反应温度、甲酸用量、双氧水用量、磷钨酸与十六烷基三甲基氯化铵的总用量和反应时间对合成环氧大豆油的影响。在大豆油：甲酸：双氧水：磷钨酸：十六烷基三甲基氯化铵=1: 0.12: 1.20: 0.0062: 0.002(以大豆油的质量为基准),反应温度70℃,反应时间6h的优化条件下,合成的环氧大豆油环氧值为6.15% ,碘值为2.46%。经FT-IR表征,大豆油的不饱和键已基本转化为环氧大豆油的环氧基团。     

Oxidation reactions in CO2: academic exercise or future green processes?

Conducting oxidation reactions using CO2 as the solvent is a promising strategy for creation of greener chemical processes that are also economical, as CO2 and water are probably the only solvents that can be used in oxidation reactions without the formation of any solvent byproducts. However, it must be noted that the promise of CO2-based oxidation still dwarfs the actual realization of CO2-based oxidation processes. Nevertheless, there is extensive literature on the use of CO2 as the solvent for the oxidation of cyclohexane (adipic acid synthesis), cumene oxidation (phenol synthesis), and epoxidation (propylene oxide synthesis). In all of these studies, knowledge of the phase behavior is crucial toward understanding the effects of pressure and temperature on reaction outcomes. To date, much of the research in this field has involved simply using CO2 as a "drop-in" replacement for a conventional organic solvent; it will be interesting in the future to see if the use of CO2 can be combined with innovations in catalyst and reactor design to create truly green oxidation processes where the use of CO2 is not merely tolerated but truly supports process and chemistry innovation.