Preparation of Aminated Macroporous Polyvinyl Alcohol Resins and Evaluation for Bilirubin Adsorption

In the present study we prepared macroporous polyvinyl alcohol beads. A series of bilirubin adsorbents were generated by immobilization of eight amine agents to the beads as ligands. The adsorption of bilirubin was evaluated by in vitro static and dynamic adsorption tests. The results show that these adsorbents have excellent adsorption efficiency and capacity. Among the eight ligands, trimethylamine （TMA）, triethylamine （TEA） and 1,6- hexanediamine （HDA） showed the highest adsorption capacity. The adsorption equilibrium can be achieved in half an hour, and the adsorption percentage of bilirubin was up to 80%. Static electricity and hydrophobie interaction played the main role in bilirubin adsorption, and the adsorption was found to match the monolayer model. The excellent adsorption of these adsorbents indicates their potential in clinical treatment.

Curing Reaction Kinetics of Epoxy Resin Using Dicyandiamide Modified by Aromatic Amines

The curing reaction and reaction mechanism of epoxy resin E-44, for which aromatic amine modified dicyandiamide was used as a curing reagent, were investigated by means of differential scanning calorimetry （DSC）. The results showed that the modified dicyandiamide had better curing characteristic than unmodified dicyandiamide for epoxy resin E-44, and the curing reaction could be carried out at moderate temperature. Apparent activation energy of the curing reaction was decreased appreciably from 123.829 kJ/mol to 61.550-64.405 kJ/mol, and reaction order was decreased from 0.941 to 0.896-0.900. Curing reaction mechanism also was discussed.

Partial amination of cationic exchange resins and its application in the hydration of butene

In this work, the amination of sulfonated polystyrene resin with alkyl secondary amine is investigated. The catalytic activities of the modified resins are determined through the hydration of l-butene. The optimum chain length and the best range of amination rate are determined. It is found that the single-pass conversion of 1 -butene was raised 2% on average, and the relative activity was increased over 30% after modification. A hypothesis about the enhancement of catalytic activities by the inclusion of alkyl chain to wrap up the butene molecule is proposed.

An Efficient and Novel Synthesis of Carbamate Esters from the Coupling of Amines, Halides and Carbon Dioxide in the Presence of Basic Resin

A convenient, efficient, one-pot, novel process has been developed for the synthesis of carbamates from corresponding alkyl halides and amines using basic resin/CO2 system.

Statistical deduction and experimental verification on kinetic equations for the curing reactions of epoxy resins/amines

Based on three typical mechanisms (second-order, third-order and competitive mechanisms) for the curing reactions of the epoxy resins with amines, a pair of the kinetic equations (for primary and secondary aminations) was presented to explain the uniformity and relationship among the three different kinetic mechanisms of the reactions. The presented macro-equations were deduced from the kinetic micro-equations by the statistics method. And the constitutive equations were verified by experimental data at different reaction times and temperatures (95°C, 60°C and 39°C), taking diglycidyl ether of bisphenol A (DGEBA) /ethyleneamine (EA) as a model.

Comparative Efficacy of Polyamine-Based Scavenger Resins

Polyamine-based scavenger resins containing 2, 3 and 4 nitrogen atoms have been prepared and their comparative efficacy to scavenge appropriate electrophilic chemicals (acids, acid chlorides, isocyanates and aldehydes) from solutions has been studied. As expected, the scavenging efficiency is directly proportional to the number of nucleophic nitrogens present on the resin. The results have been compared with the performance of the popular scavenger resin, namely, tris(2-aminoethyl)amine resin, to conclude that the low-cost polyamine resins now prepared can be conveniently used as effectively as the expensive commercial product.

INFLUENCE OF MOLECULAR STRUCTURES OF SECONDARY AMINE TERMINATED POLY(ESTER-AMINE)S ON THE CURING PERFORMANCE WITH EPOXY RESIN

Five secondary amine terminated poly（ester-amine）s （defined as PEA） with controlled molecular structures were synthesized through reacting excessive piperazine with phthalicdiglycol diacrylate （PDDA） and 1,1,1-trimethylolpropane triacrylate （TMPTA） at a constant secondary amine/acrylate group ratio of 1.5/1 and at different PDDA/TMPTA molar ratios. Both IR and ^1H-NMR spectra indicated that all acrylate groups were consumed in the reaction, based on which the structural parameters were calculated from the ^1H-NMR spectra. With decreasing PDDA/TMPTA ratio, the content of secondary amine, degree of branching, molecular weight, Tg and Td increased accordingly. These polymers were further used as both crosslinkers and flexibilizers for a linear epoxy resin E51 to form cured films under ambient condition. The gel content, relative hardness and Tg of the resulting films increased as PEA molecules changed from linear to highly branching structures. Due to the flexibility of PEA molecules, all the films possessed excellent mechanical performance.

Kinetics of Reaction of Bromo-epoxy Resin with Oleic Acid catalyzed by Dimethyl benzyl amine

The kinetics of reaction of bromo-epoxy resin with oleic acid in the presence of dimethylbenzylamine catalyst was studied. The reaction is a zero order reaction with respect to oleic acid, first order with respect to epoxy group and 0. 74 order with respect to dimethylbenzylamine. The reaction rate constants at various temperatures and activation energy were determined. The mechanism of this reaction was discussed. Keywords Tetrabromobisphenol-A, Bromo-epoxy resin, Oleic acid kinetics, Reaction mechanism

Investigation on the Structure and Curing Performances of Secondary Amine Terminated Hyperbranched Poly(ester-amine)s

Three secondary amine terminated hyperbranched poly（ester-amine）s （defined as HPEA1, HPEA2 and HPEA3） were synthesized from piperazine （A2） and trimethylolpropane triacrylate （TMPTA, B3） at their molar ratios of 2.5：1, 2.25：1 and 2.0：1, respectively. The polymers were analyzed by 1H NMR, GPC, DSC and TGA. The results indicated that the ratio of secondary amine to tertiary amine and the content of secondary amine decreased, while the molecular weight, molecular weight distribution and glass transition temperature （Tg） increased from HPEA1 to HPEA3. Due to their reactive terminal groups and flexible chains, these polymers further reacted with an epoxy resin （E51） to form cured films under ambient conditions. With increasing the ratio between secondary amine groups and epoxy groups from 1：2 to 2：1, the gel content, film hardness and onset decomposing temperature of the cured samples increased. The good film performances should make the polymers as the components of non-solvent coating materials.

氧化叔胺树脂制备及对水中刚果红的吸附性能研究

以丙烯酸二甲氨基乙酯为单体、三羟甲基丙烷三甲基丙烯酸酯为交联剂,通过悬浮聚合法制备出叔胺树脂(TAR),然后经H_(2)O_(2)改性得到氧化叔胺型树脂(TAOR)。采用场发射扫描电镜(SEM)、傅里叶变换红外光谱(FT-IR)、氮气吸附-脱附曲线和热重(TG)等技术手段对其结构进行了表征。以刚果红(CR)为模型对象污染物,并通过正交试验对TAOR最佳合成工艺进行了优化研究,同时,研究了TAOR投加量、溶液pH、离子强度和共存组分等因素对水中CR吸附性能的影响,并对其吸附过程中吸附动力学模拟。结果表明:CR的吸附量随着pH和离子强度的增加而减少,共存离子和腐殖酸对TAOR树脂吸附CR有一定的抑制作用。CR在TAOR上的吸附过程符合拟二级动力学吸附模型,Langmuir等温吸附符合模型可以很好地描述TAOR对溶液中CR的吸附过程,最大吸附量为101.9mg/g(pH=6.0和25℃)。吸附热力学结果表明,CR在TAOR上的吸附是一个自发的物理吸附过程,其吸附机制单层子化学作用控制机制。FT-IR和X射线光电子能谱技术(XPS)结果进一步显示,TAOR上的氧化胺结构参与CR吸附。脱附再生实验发现,1.0mol/L NaOH溶液脱附效果最优,经5次循环再生使用,TAOR的吸附性能没有明显下降。

受阻胺光稳定剂与紫外吸收剂协同改进GPPS树脂抗紫外光老化性能研究

采用黄度指数仪、激光扫描共聚焦显微镜(CLSM)和透光率雾度测定仪等研究了2种紫外光吸收剂(UV-A、UV-B)与受阻胺光稳定剂(HALS)协同使用对通用级聚苯乙烯(GPPS)树脂抗紫外光老化性能的影响。结果表明:加入HALS,UV-A,UV-B均可有效抑制GPPS树脂因紫外光老化作用而发生降解。在紫外光环境下,紫外光吸收剂(UV-A,UV-B)对样品抗紫外老化性能的提升效果均优于HALS,其中,UV-A最优。HALS与2种紫外光吸收剂(UV-A,UV-B)复配时均表现出良好的抗紫外光老化协同作用。

厚朴酚环氧树脂涂层的制备及综合防护性能研究

采用联苯结构的生物质原料厚朴酚合成生物基环氧树脂,以柔性聚醚胺固化剂(D230、D400、D2000及T403)进行固化制备生物基环氧抗冲蚀涂层,探究聚醚胺分子量与官能度对厚朴酚环氧树脂力学性能、防腐性能以及抗冲蚀防护性能的影响,阐述厚朴酚环氧涂层抗冲蚀磨损机理。结果表明:D230固化的厚朴酚环氧涂层在3.5%(质量分数)NaCl溶液中浸泡15 d后仍具有较高的阻抗值(1.25×10^(11)Ω·cm^(2));以T403固化可获得高拉伸强度(26.59 MPa)、低摩擦系数(0.373)和磨损率[0.0183 mm^(3)/(N·m)]涂层;D2000固化的厚朴酚环氧涂层在抗冲蚀测试中表现出较低质量损失(244.74 mg)与体积损失(157 mm^(3))。在固/液/气三相流冲蚀作用下,D2000较长的柔性链段,赋予厚朴酚环氧涂层更好的弹性和柔韧性,降低了冲蚀介质的冲击作用,从而表现出优异的抗冲蚀性能。

胺液净化中离子交换树脂的失效与再生研究

离子交换法常被应用于胺液净化领域,但是在低碱液浓度下部分离子交换树脂难以再生,存在失效的问题。利用SEM、EDS、FT-IR和XPS等手段对树脂的失效原因进行分析,并利用电再生的方法对失效树脂的再生进行了探究。实验结果显示,树脂净化胺液前后的骨架和功能基团并未改变,但是硫元素的质量分数显著提升,结合S 2p光谱存在162.2 eV和163.4 eV 2个分裂峰,说明树脂失效的主要原因是吸附的硫离子难以解吸;对失效树脂施加电再生时树脂的交换容量提升了3.6倍,吸附的硫元素质量分数下降了57.5%,表明电再生的方式可以提高树脂的交换容量和树脂内硫离子的解吸程度。

棕榈酰化三聚氰胺的合成与性质

以十六碳酰氯(棕榈酰氯)为酰化剂与三聚氰胺进行反应,制备了十六碳酰化三聚氰胺(PM),并优化了反应条件;探究了棕榈酰氯、草酰氯、磺酰氯及丙烯酰氯四种酰化剂,制备得到相应的酰化三聚氰胺,对比了反应条件和产物性能;最后对比了密胺树脂(MF)以及棕榈酰化密胺树脂(PMF)的性能。用FT-IR、^(1)H-NMR以及SEM表征分析了PM的结构,用TGA研究了PM的热稳定性。结果表明,该合成方法以及纯化方法产率高(90%),产物热分解温度高(367.4℃),PM粉末具有疏水性,其水接触角最高达143°。PMF树脂比MF树脂具有更高的固含量(59.8%)和更高的粘度(150.6 m Pa·s),对MF树脂后续的研究应用有着重要意义。

胺液在线深度复活装置的设计及应用

目的解决天然气净化厂脱硫装置胺液系统中由于醇胺溶液自身降解与外来污染所导致的脱硫性能下降、腐蚀穿孔、发泡停产等一系列问题。方法对溶液系统污染物来源进行解析,为有效降低溶液中的污染物、降解物和烃类杂质等,采取了以下措施:①增设原料气预处理设施;②设置溶液过滤器;③增设胺液在线深度复活系统等设施。结果胺液在线深度复活装置可有效去除溶液中热稳定盐及致泡物质,使溶液的发泡高度由500 mm降至30 mm,消泡时间由110 s降至5 s。结论通过对胺液进行深度复活,保证溶液的洁净度,恢复溶液性能,可大幅度降低脱硫装置的发泡频率,更好地保障天然气净化装置的平稳高效运行。

核电厂二回路系统有机胺应用研究

降低核电厂二回路系统设备管道腐蚀和减少腐蚀产物进入蒸汽发生器,对维持二回路安全运行和蒸汽发生器可靠性具有重要意义。运行核电厂二回路设备管道的金属腐蚀程度主要取决于其所在部位运行温度下的p H值即p Ht值,以提高二回路系统所有部位p Ht值为目标,分析主要有机胺吗啉、乙醇胺、3-甲氧基丙胺、二甲胺等及其组合的性能特征,并结合这些有机胺的应用经验,探讨了主要有机胺及其组合的应用原则。对目前国内二回路有机胺的应用现状提出了改进建议:选择有机胺或其组合时应计算二回路各部位的p Ht值是否满足设备管道防腐要求,同时评估对系统树脂床运行时间的影响;碱性较强挥发性低的乙醇胺适用于二回路腐蚀产物主要来自高温疏水且凝结水精处理需要连续运行的电厂,3-甲氧基丙胺则因其碱性强挥发性适中使用范围较为广泛,吗啉因碱性较弱挥发性适中适用于凝结水精处理非连续运行的电厂,二甲胺和氨因其挥发性高适合和其他碱化剂组合使用,碱化剂组合使用可以在设备管道防腐和树脂床运行周期方面体现出更多的优势。

废弃胺肟树脂气流膨化碳化及其吸附Pb^(2+)研究

胺肟树脂作为镓的吸附树脂,在反复吸附-解吸1月后失效,孔道塌陷官能团失效,每年产生废弃树脂量大。为了对废弃胺肟树脂进行资源化利用,提出“爆米花”式气流膨化法对废胺肟树脂进行膨化扩孔处理,并探究膨化树脂对溶液Pb^(2+)离子的吸附行为,膨化实验和吸附实验结果表明:废胺肟树脂的含水率,罐体预热温度,膨化压力对膨化效果影响大;膨化树脂对溶液中对Pb^(2+)的饱和吸附容量为221.02 mg/g,吸附符合准二级动力学(R^(2)=0.9999)和Langmuir等温模型(R^(2)=0.9906),主要以化学吸附为主。研究结果为废弃胺肟树脂再生利用及溶液含铅废水处理提供一种新吸附材料,为废弃胺肟树脂对资源化处理提供一种新途径。

风电混塔用环氧拼接胶在低温下的应用性能研究

自制改性胺固化剂B1与环氧A1组份搭配使用,研究不同的胶体温度对风电用环氧拼接胶施工性能及压缩强度的影响,以及不同改性胺固化剂与不同A组份搭配使用时,风电用环氧拼接胶的施工性能及压缩强度。结果表明:当自制改性胺B1作为固化剂与A1复合使用,并维持胶体温度在20、25℃时,风电用环氧拼接胶具有较好的施工性能和压缩强度;因此建议冬季环境温度在-10~-7℃时,将风电用环氧拼接胶A、B组份升温至20℃再混合使用,此时风电用环氧拼接胶的对粘弯曲性能符合T/CECS 10080—2020的要求。当环氧A4组份与自制改性胺固化剂B1复合使用时,室温调节30 min后,风电用环氧拼接胶的7、14 d压缩强度分别为56.5、71.9 MPa;与B3复合使用时,其7、14 d压缩强度分别为61.2、68.2 MPa,14 d强度低于自制改性胺固化剂B1。

环氧大豆油仲胺树脂的合成及性能研究

以环氧大豆油与苯胺反应制备了环氧大豆油仲胺树脂,较优合成条件为0.3%三氟化硼乙醚催化、60~80℃反应24~48 h。控制苯胺/ESO反应投料物质的量比为2.5~3.0、实际反应物质的量比为2.0~2.5时得到的仲胺树脂具有较低的黏度及适当的反应活性,与HDI三聚体、TDI/TMP加成物、聚合MDI等种类固化剂配合使用,得到聚脲涂层具有优良的综合性能。

固体火箭发动机壳体碳纤维复合材料的溶胀降解

目的 降解固体发动机壳体,回收其高性能碳纤维。方法 首先通过N-甲基吡咯烷酮(NMP)、二甲基甲酰胺(DMF)、二甲基乙酰胺(DMAC)、乙酸(CH3COOH)4种有机溶剂对混合树脂为基体的CFRP溶胀效果比较,分析不同的因素(温度、时间)对溶胀的影响。然后将溶胀后的固体发动机壳体复合材料在二乙二醇(DEG)-氢氧化钾(KOH)体系中低温常压降解处理。结果 经过2h溶胀处理,NMP对固体发动机壳体复合材料具有最好的溶胀效果,溶胀率达到180.81%,远超DMF、DMAC、CH3COOH溶胀效果。温度对各溶剂的溶胀效果均存在明显的影响。溶胀溶剂与聚合物基体基本不发生化学反应。可通过旋转蒸发再生。在DEG-KOH体系中,树脂降解率接近100%,同时可得到表面清洁、力学性能保留90%以上的碳纤维(CF)。结论 得到了一种固体发动机壳体复合材料绿色处理的手段,实现了胺固化环氧树脂基碳纤维复合材料的降解回收。