己二胺的生产工艺与应用

己二胺是生产尼龙-66的主要原材料。己二胺生产方法主要有己二腈法、己二醇法、己内酰胺法、己二酸法、丁二烯法等。主要介绍了目前己二胺合成工业化、大型化常用的生产工艺,从己二胺催化加氢的反应机理及Raney-Ni催化剂的应用角度出发,为改进现有生产工艺及优化、更新催化剂配方起到重要的指导作用。     

1,6-六亚甲基二氨基甲酸甲酯的清洁合成研究

对碳酸二甲酯与己二胺甲氧羰基化反应的产品1,6-六亚甲基二氨基甲酸甲酯进行了定性分析,考察了催化剂用量、原料配比、反应时间和溶剂等操作条件对反应过程的影响。催化剂为CH3CONa或CaCl2;较好的反应条件为:n(催化剂)∶n(己二胺)=0.01∶1,n(碳酸二甲酯)∶n(己二胺)=5∶1,反应时间20h。     

环己亚胺的开发现状及市场前景

合成环己亚胺可采用很多原料,如己二胺、己二醇、己内酰胺、烷基己内酰亚胺、己内酯、丙烯醛和氧杂环庚烷等。但从原料易得和供给稳定看,只有己二胺和己内酰胺比较合理。早期生产环己亚胺的方法都是生产己二胺时的副产品,但产量受到尼龙生产规模的限制。从40年代开始,德、美、日等发达国家的专利中相继报道了己二胺在催化剂作用下经脱氨环化可制得环己亚胺,但由于未能彻底解决分子间脱氨的技术难题,目前此路线己基本淘汰。利用己内酰胺催化加氢制取环己亚胺是80年代后发展起来的一种新方法,该法在国内外都己工业化生产,技术关键是选择合适的催化剂。利用丙烯醛也可合成环己亚胺,但该法只是小试报道,未见工业化生产。     

尼龙66有望100%采用生物原料

美国Rennovia公司开发出新型催化剂及工艺,可用于以可再生原料低成本生产己二胺。该公司此前已推出可再生己二酸,今后将可以生产100%生物原料的尼龙66。     

生产己二胺用雷尼镍催化剂的研究进展

综述了己二腈催化加氢生产己二胺雷尼镍催化剂的制备方法，主要包括冶炼法、高能球磨法和激冷法制备铝镍合金。探讨了碱熔脱铝的活化条件，分析了活化后形成的催化剂微结构对其活性及选择性的影响，对比了与负载型非晶态合金催化剂制备方法的不同。     

六亚甲基二氨基二甲酸甲酯的制备

六亚甲基二氨基二甲酸甲酯是绿色合成六亚甲基二异氰酸酯(HDI)的前体。利用碳酸二甲酯与己二胺反应生成六亚甲基二氨基二甲酸甲酯,考察了在新型催化剂CH3COONa作用下反应的影响条件。得出了反应的较佳工艺:己二胺和催化剂的摩尔比为10,碳酸二甲酯和己二胺的摩尔比为8,反应温度353 K,反应时间8 h。并对反应机理及合成工艺进行了讨论。     

雷尼镍催化剂在己二腈加氢反应中的应用与研究

在生产己二胺的工艺中,雷尼镍催化剂作为己二腈加氢反应的主要催化剂。对己二腈加氢反应中的雷尼镍催化剂的物化特性进行介绍,对该催化剂的活化、钝化进行了研究,该催化剂在己二腈加氢反应中的应用及存在的问题进行研究,认为催化剂定量置换可以很好地解决活性降低和流动性变差这一问题。     

胡椒碱合成胡椒酸己二胺的中试放大研究

采用钠的催化剂，以无水乙醇和己二胺原料，对胡椒酸乙酯合成胡椒酸己二胺的工艺进行了中试放大研究。在中试规模的工艺流程上，考察了反应温度、物料循环比和催化剂等因素对合成物的影响。在氮气保护下n（胡椒酸乙酯）：n（无水乙醇）：n（己二胺）=2：25：2、反应温度65～72℃的条件下，，以胡椒酸乙酯+均己二胺为目的产物的单程收率为79%左右。实验结果达到了工业化生产的要求。     

聚六亚甲基双胍盐酸盐的合成工艺研究

以1,6-己二胺盐酸盐和1,6-双氰基胍基己烷为原料,水为溶剂,盐酸为催化剂合成了聚六亚甲基双胍盐酸盐(PHMB)。用紫外分光光度法对产物进行了表征。研究了原料1,6-己二胺盐酸盐与1,6-双氰基胍基己烷物质的量比、水的用量、催化剂、反应温度、反应时间对产物收率的影响,得出了最优条件:n(1,6-己二胺盐酸盐):n(1,6-双氰基胍基己烷)=1:0.95,m(1,6-己二胺盐酸盐):m(水)=1:1,盐酸为催化剂、反应温度为160℃、反应时间为5h。在该条件下,PHMB的分子量可以达到2600,收率为98.4%。     

以尿素为羰化剂合成六亚甲基二氨基甲酸酯的工艺研究

对尿素作为羰基化试剂合成六亚甲基二氨基甲酸酯进行了可行性研究,用正交实验法确定了合成反应的较佳工艺条件：温度225℃,反应时间5h,催化剂用量、尿素用量与己二胺的物质的量比为0．0005：2．5：1。分析讨论了反应温度、反应时间、催化剂用量等工艺条件对产物收率的影响,发现催化剂最佳用量为己二胺的0．1％（物质的量分数）,并验证副产物是完全可以回用的。     

Synthesis of nitrogen-doped onion-like carbon and its use in carbon-based CoFe binary non-precious-metal catalysts for oxygen-reduction

Nitrogen-doped onion-like carbon-rich materials were synthesized by heat treatment of a “hybrid” containing hexamethylene diamine complex in the presence of Co and Fe species while preparing non-precious metal electrocatalyst for oxygen-reduction. As demonstrated by electrochemical rotating disk electrode and fuel cell tests, the binary CoFe-based catalyst containing graphitized onion-like carbon nanostructures provides for improved performance relative to the single Fe-based catalyst in which no such carbon structure was observed. In the binary catalysts, variation of the ratios of Co to Fe and the total metal loading during the synthesis leads to a markedly different activity and four-electron selectivity for oxygen reduction. The optimized binary catalyst was studied in fuel cell lifetime tests using both constant current and voltage models, showing a good combination of activity and durability. Possible reasons for the improved performance of the CoFe-based binary catalyst are discussed. The graphitized onion-like carbon structure exclusively derived from Co in this work may be providing a robust matrix to host non-precious metal active sites, which would prevent water flooding of them, and increase the resistance to oxidative attack in the oxygen cathode, thereby leading to an improvement in performance durability.     

骨架镍催化剂在腈类加氢中的应用

介绍3种类型骨架镍催化剂在己二腈加氢中的应用,并对加氢结果进行比较。结果表明,3种类型骨架镍催化剂均可以实现己二腈加氢,己二腈转化率和己二胺选择性较高。同时对其他二腈如2-甲基戊二腈和丁二腈进行加氢研究,进一步表明骨架镍在腈类加氢中具有独特优势。     

氯乙酰化聚苯乙烯树脂的胺基化反应

以氯乙酰化聚苯乙烯(PS-Acyl-Cl)代替氯甲基化聚苯乙烯作为载体,引入乙二胺(EDA)和己二胺(HMD)得到2种胺基树脂。考察了反应时间、油浴温度、物料比、溶剂体系等对胺化反应的影响,在最佳反应条件下,乙二胺和己二胺树脂的担载量分别达到1.60 mmol/g和2.6 mmol/g。将2种胺基树脂进行比较:在相同条件下,制备的己二胺树脂的担载量明显高于乙二胺树脂。该方法避免了氯甲基化法存在的弊端,并消除了烷基化引起的二次交联及多取代等副反应。制备的胺基树脂可以作为一个活性中间体,进一步衍生化制备多种功能介质。     

酮亚胺对水性聚氨酯性能的改进

用丙酮分别和乙二胺、己二胺反应制备酮亚胺,并以其作为潜伏性扩链剂改善水性聚氨酯(PU)的性能。研究了酮亚胺以不同方式、加量对水性PU漆膜的厚度、硬度、耐水性、耐酸性、热稳定性和机械性能的影响。结果表明,采用丙酮缩乙二胺扩链的水性PU乳液的漆膜的耐水性优于用丙酮缩己二胺和用水扩链的PU乳液的漆膜,且加入过量的酮亚胺扩链效果较好,但其热稳定性并没有得到明显提高。     

熔融聚合法制备一种具有双螺环结构的膨胀型阻燃剂及其性能研究

采用3,9二氯-2,4,8,10四氧杂-3,9-二磷杂螺环［5,5］3,9二氧十一烷 (SPDPC)与己二胺,在氮气保护下采用熔融聚合法合成了一种新型膨胀型阻燃剂螺环磷酸酯己二胺共聚物（SPHD）,通过测试特性黏度确定了最佳合成条件为：反应温度165 ℃,n(SPDPC)/n(己二胺)=1/1.1,反应时间约4 h,产率达84 %;采用红外光谱、核磁共振氢谱对共聚物SPHD进行了结构表征,证实了目标产物的成功制备;热重分析显示其具有良好的热稳定性;通过与聚磷酸铵（APP）复配,应用于低密度聚乙烯（PE-LD）中,初步测试了其阻燃性能,当SPHD含量为15 %时,复合材料的氧指数值为27.2 %,UL94达到V-0级。     

六亚甲基亚胺合成研究

对ε-己内酰胺加氢制六亚甲基亚胺的工艺进行了研究,筛选了催化剂,考察了氢气流量、反应温度、反应压力以及催化剂量对反应收率的影响。实验结果表明,采用Ra-Co为催化剂,以二乙二醇二甲醚为溶剂,氢气流量0.3 m3/h,反应压力3.0 MPa,反应温度220~230℃,催化剂用量10 g时,六亚甲基亚胺的收率达到44.2%。与传统工艺相比,本研究中催化剂及溶剂可连续使用,降低了成本。     

Relaxations in thermosets. XXV. Calorimetric studies of the curing kinetics of pure and rubber-containing epoxy-based thermosets

The curing kinetics of diglycidyl ether of bisphenol-A, with ethylene diamine, propylene diamine, and hexamethylene diamine, with 60 wt % amine-terminated butadiene acrylonitrile (ATBN) and without, have been measured under both isothermal and ramp-curing conditions. The phase separation of ATBN is undetectable by calorimetry, but has a significant effect on both the rate of curing and the extent of cure. In all cases, its presence decreases the extent of cure and lowers the T_g of the thermoset formed. The total heat of reaction for the curing is 445 ± 15 J/g and remains unaffected by both the presence of an elastomer and the increase in the molecular size of the curing agent. None of the formalisms available for the curing kinetics of epoxy-based thermosets is consistent with the results for the neat thermosets. The average activation energy for the reactions increases from 107 to 150 kJ/mol when ethylene diamine is replaced by hexamethylene diamine, but curing reaches near completion in a shorter time with the latter than with the former. The T_g of the latter thermoset is lower than that of the former and follows a decreasing trend with increase in the molecular size of the curing agent—an effect that is related to the increase in the length of cross-links in the network structure. © 1993 John Wiley & Sons, Inc.     

Relaxations in thermosets. XXIX. Calorimetric studies of the curing kinetics of nonstoichiometric diamine–epoxy mixtures

The curing kinetics of nonstoichiometric mixtures of diglycidyl ether of bisphenol A, with ethylene diamine, propylene diamine, and hexamethylene diamine have been measured under both isothermal and ramp-curing condition. Their kinetics are faster than for stoichiometric compositions and the reactions reach completion. The total heat evolved for the amine-rich composition is greater than for the amine-deficient. None of the available formalisms is consistent with the results. This and the variation in the heat of reaction indicate that steric effects are important for both the reaction rate and the heat evolved. It is argued that the standard heat of reaction of primary amine with the epoxide group differs from that of secondary amine. © 1994 John Wiley & Sons, Inc.     

Modified PMMA monosize microbeads for glucose oxidase immobilization

Glucose oxidase (GOD) was immobilized onto modified polymethylmethacrylate (PMMA) microspheres by covalent bonding. Monosize PMMA microbeads with 1.5 μm diameter were produced by dispersion polymerization of methylmethacrylate by using polyvinyl alcohol as a stabilizer. Hydroxyl groups on the microbeads were first converted to aldehyde groups by periodate oxidation. Three amino compounds, namely ammonium hydroxide, ethylene diamine and hexamethylene diamine were incorporated through the aldehyde groups. Then, GOD molecules were immobilized through the spacer-arms by using glutaraldehyde. The highest amount of immobilization and activity were obtained in which hexamethylene diamine was used as the spacer-arm with 14 atom length, and were 2.1 mg g⁻¹ polymer and 129 IU g⁻¹ polymer, respectively. The optimal conditions for GOD immobilization were obtained as follows: pH, 6.0; temperature, 30 °C; immobilization time, 60 min; and GOD initial concentration, 0.10 mg ml⁻¹. The optimal conditions for the GOD-immobilized PMMA microbeads were at pH 6.0 and at a temperature of 30 °C. The K_m and V_max values of the GOD-immobilized PMMA microbeads were, 13.79 mM and 26.31 mM min⁻¹ calculated by non-linear regression, respectively.     

抗静电剂对抗静电PET纤维表面形态的影响

以己二酸聚乙二醇胺盐,己二酸己二胺盐和ε－己内酰胺为单体,经真空共缩聚合成共缩聚醚酰胺,用ＤＳＣ和ＴＧＡ测定了其热性能。将共缩聚醚酰胺和ＰＥＴ熔融共混熔纺成纤维,测定了纤维的抗静电性能并用扫描电镜研究了抗静电纤维的微区形貌。