磷钨钼杂多酸催化合成环己酮乙二醇缩酮

以H3PW6Mo6O40为催化剂，对以环己酮与乙二醇为原料合成环己酮乙二醇缩酮的反应条件进行了研究，较系统地研究了酮醇物质的量比、催化剂用量、反应时间对收率的影响。实验结果表明，在n（环己酮）：n（乙二醇）=1．0：1．5，催化剂用量占反应物料总质量的0．8％，反应时间0．75h，带水剂环己烷8mL的条件下，环己酮乙二醇缩酮的收率为84.9％。     

Application of lipase immobilized on nylon‐6 for the synthesis of butyl acetate by transesterification reaction in n‐heptane

A purified alkaline thermotolerant bacterial lipase from Bacillus coagulans BTS‐3 was immobilized on nylon‐6 matrix activated by glutaraldehyde. The matrix showed ～ 70% binding efficiency for lipase. The bound lipase was used to perform transesterification in n‐heptane. The reaction studied was conversion of vinyl acetate and butanol to butyl acetate and vinyl alcohol. Synthesis of butyl acetate was used as a parameter to study the transesterification reaction. The immobilized enzyme achieved ～ 75% conversion of vinyl acetate and butanol (100 mmol/L each) into butyl acetate in n‐heptane at 55°C in 12 h. When alkane of C‐chain lower or higher than n‐heptane was used as an organic solvent, the conversion of vinyl acetate and butanol to butyl acetate decreased. During the repetitive transesterification under optimal conditions, the nylon bound lipase produced 77.6 mmol/L of butyl acetate after third cycle of reuse. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Coloring effect of the organic hybrid of polyamide 6 and N,N′‐ethylene‐bis(tetrabromophthalimide)

Coloring study in organic hybrid of polyamide (PA6) and N,N′‐ethylene‐bis(tetrabromophthalimide) (EPT), where the chromophore was self‐assembled by hydrogen bonding formed between PA6 molecular chains and EPT compound, have been characterized by several techniques. CS930 double wavelength lamella scanner was employed to measure the change of color. The existence of hydrogen bonding in PA6/N‐N′‐ethylene‐bis (tetrabromophthalimide) (PA6EPT) was investigated with Fourier transform infrared (FTIR), the results of which were compared with that of PA6 with the same thermal history. FTIR spectra at room temperature revealed that there is essentially hydrogen bonding between PA6 and EPT. The crystallization behavior of PA6EPT affected by hydrogen bonding was studied by using FTIR. The temperature‐dependent behavior of both PA6 and PA6EPT was studied by temperature‐FTIR spectroscopy and differential scanning calorimetry (DSC). With temperature increasing, changes in sensitive, high‐resolution absorbance spectra are observed as dissolve‐volatilizing thin film. Temperature‐FTIR results showed that the hydrogen bonding in PA6EPT attenuated and dissociated considerably at a smaller rate than PA6, that is to say, hydrogen bonding in PA6EPT is more stable than that in PA6. DSC showed that the melting temperature of PA6EPT and PA6 are similar. However, the crystalline degree and crystalline temperature and melting enthalpy of PA6 and PA6EPT are different. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 594–600, 2007     

Effect of in situ synthesized macroactivator on morphology of PA6/PS blends via successive polymerization

In situ polymerization and in situ compatibilization was adopted for preparation of ternary PA6/PS‐g‐PA6/PS blends by means of successive polymerization of styrene, with TMI and ε‐caprolactam, via free radical copolymerization and anionic ring‐opening polymerization, respectively. Copolymer poly(St‐g‐TMI), the chain of which bears isocyanate (? NCO), acts as a macroactivator to initiate PA6 chain growth from the PS chain and graft copolymer of PS‐g‐PA6 and pure PA6 form, simultaneously. The effect of the macroactivator poly(St‐g‐TMI) on the phase morphology was investigated in detail, using scanning electron microscopy. In case of blends with higher content of PS‐g‐PA6 copolymer, copolymer nanoparticles coexisting with the PS formed the matrix, in which PA6 microspheres were dispersed evenly as minor phase. The content of the compositions (homopolystyrene, homopolyamide 6, and PS‐g‐PA6) of the blends were determined by selective solvent extraction technique. The mechanical properties of PA6/PS‐g‐PA6/PS blends were better than that of PA6/PS blends. Especially for the blends T10 with lower PS‐g‐PA6 copolymer content, both the flexural strength and flexural modulus showed significantly improving because of the improved interfacial adhesion between PS and PA6. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Direct synthesis of La9.33Si6O26 ultrafine powder via sol–gel self-combustion method

Single phase La_9.33Si₆O₂₆ ultrafine powder, as a kind of highly activated precursor to prepare medium-to-low temperature electrolyte for solid oxide fuel cells (SOFCs), has been successfully synthesized via a non-aqueous sol–gel and self-combustion approach from the starting materials: lanthanum nitrate (La(NO₃)₃·6H₂O), citric acid, ethylene glycol (EG), tetraethyl orthosilicate (TEOS) and ammonium nitrate. The details of gel's self-combustion were investigated by DTA–TG and the structural characterization of as-synthesized powder from self-combustion was performed by XRD and SEM. The results show that La_9.33Si₆O₂₆ single phase of apatite-type crystal structure can be directly synthesized by sol–gel self-combustion method without further calcinations on the condition that the molar ratio (R) of NO₃⁻ to citric acid and ethylene glycol being 6:1. Such powders composed of well-dispersed particles with an average size of 200 nm and a specific surface area of 5.54 m²/g. It can be sintered to 90% of its theoretical density at 1500 °C for 10 h, about 200 °C lower than the sintering temperature for the powder derived from traditional solid reactions. The sintered material has a thermal expansion coefficient of 9.2 × 10⁻⁶ K⁻¹ between room temperature and 800 °C.     

全消光锦纶6全拉伸丝生产工艺探讨

用国产全消光锦纶6切片,在常规FDY纺丝设备上可生产出高质量全消光锦纶6全拉伸丝(FDY),就纺丝温度、喷丝板、冷却条件、热辊温度、拉伸等工艺条件对全消光锦纶6FDY的影响进行了探讨。     

纳米银系抗菌锦纶6的制备与应用

通过在纺丝过程中添加无机层状纳米银磷酸盐抗菌母粒制备出了一种持续、高效、广谱的抗菌锦纶6纤维。研究发现:采用低温纺丝技术,可有效地控制熔体氧化降解,减少断头和飘丝;减小侧吹风风速,降低纺丝速度,提高丝条上油量可降低条干不匀率;降低DTY加工速度、拉伸比、D/Y比及热箱温度有利于克服抗菌POY物理性能变化给DTY加工带来的不利因素。扫描电镜显示:抗菌粉体在纤维表面均匀分散,平均直径约1.0μm,较少发生团聚。抗菌实验表明:经洗涤100次后,纤维抗菌性能仍达99%。     

2,6-双(4-氨基苯氧基)苯腈的合成及其聚酰亚胺

从4-氨基酚和2,6-二氯苯腈出发,合成了2,6-双(4-氨基苯氧基)苯腈单体,总收率为55%。由该单体与4,4′-(六氟亚丙基)双-邻苯二甲酸酐共聚合,经热环化脱水反应得可溶性聚酰亚胺,可溶于NMP、DMF、DMAc等溶剂。     

四硝酸甘露醇酯类化合物的合成和抑菌活性

以海藻中提取的海洋活性物质D-甘露醇为原料,先与丙酮发生缩合反应,将1,2,5,6位的羟基保护起来,再对3,4位的羟基分别甲醚化、甲基磺酸和对甲苯磺酸酯化后,脱去异亚丙基保护基团,还原1,2,5,6位的羟基,并对其进行硝酸酯化,合成了3个标题化合物,产率在77%以上。合成的部分中间体和目标产物的结构,经红外光谱(IR)、核磁共振氢谱(1HNMR)、碳谱(13CNMR)、质谱(MS)和元素分析进行了确证。抑菌实验表明,这3个1,2,5,6-四-O-硝酸甘露醇酯类化合物具有一定的选择性,仅对金黄色葡萄球菌(G Staphylococcus aureus)有抑制作用,最小抑制浓度为50μg/mL,抑制作用没有太大的差别。