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41.
淀粉丙烯酸接枝共聚吸水性树脂的研究进展 总被引:4,自引:0,他引:4
基于淀粉丙烯酸接枝共聚作为吸水性树脂具有环保和可生物降解的优良特性 ,目前 ,人们普遍关注的是如何提高其吸水性 ,抗温性 ,控制水份释放 ,压力下保水 ,以及电解液的吸收等。这些特性的改进将使产品的用途更为广泛 ,可以预见 ,淀粉丙烯酸接枝共聚作为吸水性树脂具有广阔的应用和发展前景。 相似文献
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Xiaohong Gu Tinh Nguyen Mounira Oudina David Martin Bouchra Kidah Joan Jasmin Aziz Rezig Lipiin Sung Eric Byrd Jonathan W. Martin Derek L. Ho Y. C. Jean 《Journal of Coatings Technology and Research》2005,2(7):547-556
Atomic force microscopy (AFM) has been used to study the morphology and microstructure of an amine-cured epoxy before and
after outdoor exposure. Measurements were made from samples prepared in an essentially CO2-free, H2O-free glove box and from samples prepared in ambient conditions. For those prepared in a CO2-free glove box, AFM imaging was conducted on (1) an unexposed air/coating surface, (2) an unexposed coating bulk, (3) an
unexposed coating/substrate interface, and (4) a field exposed air/coating surface. For samples prepared in ambient conditions,
only the unexposed air/coating surface was investigated. The same regions of the exposed samples were scanned periodically
by the AFM to monitor changes in the surface morphology of the coating as UV exposure progressed. Small angle neutron scattering
and Fourier transform infrared spectroscopy (FTIR) studies were performed to verify the microstructure and to follow chemical
changes during outdoor exposure, respectively. The results have shown that amine blushing, which occurs only under ambient
conditions, had a significant effect on the surface morphology and microstructure of the epoxy. The surface morphology of
the samples prepared under CO2-free, dry conditions was generally smooth and homogeneous. However, the interface and the bulk samples clearly revealed a
two-phase structure consisting of bright nodular domains and dark interstitial regions, indicating an inhomogeneous microstructure.
Such heterogeneous structure of the bulk was in good agreement with results obtained by small angle neutron scattering of
unexposed samples and by AFM phase imaging of the degraded sample surface. The relationship between submicrometer physical
changes and molecular chemical degradation is discussed.
Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago,
IL. 相似文献
45.
The carboxyl‐terminated butadiene‐a‐acrylonitrile rubber (CTBN) has been proved to be the most effective toughener for cyanate ester (CE) resin. This work mainly focuses on the different modification effects caused by the addition of CTBN with different acrylonitrile content. The phase separation, morphology of fracture surface, and physical properties of the blends are studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic mechanic analysis (DMA), and thermogravimetric analysis (TGA). It is testified that the compatibility and toughness between CE and CTBN had a positive correlation with the acrylonitrile content of CTBN. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
46.
An attempt was made on the modification of the tetraglycidyl‐4,4′‐diaminodiphenyl methane/diaminodiphenyl sulfone (TGDDM/DDS) system to improve properties for several industrial applications. Epoxy resins [TGDDM and 1‐glycidyloxy‐4‐methoxy phenol (GMP)] were synthesized in the laboratory. Also, a new cyanate ester and phenoxy polymer were synthesized and characterized by FTIR, 1H‐/13C‐NMR, and thermal studies. GMP was added as a diluent and a new cyanate ester (DCDPT) was introduced to reduce the tight crosslinking density. Further, a new phenoxy polymer was added to improve the toughness property. A variety of neat resin casts using different compositions of the blends were made and their physical, chemical, thermal, and mechanical properties were evaluated to study the effect of GMP as a diluent, cyanate ester as a comonomer, and phenoxy polymer as a toughener. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2963–2973, 2003 相似文献
47.
本文对模拟的含酚废水,采用新型技术对乳状液膜法脱酚进行了进一步的探讨。对所采用的制乳设备———撞击流-旋转填料床对制乳率、提取设备———旋转填料床对脱酚率、破乳设备———无机微孔膜法破乳的重要参数(如透过压方式、膜孔径等对膜通量和破乳率的影响)进行了研究。并且讨论了破乳后的油相回用情况。实验结果表明:撞击流-旋转填料床的制乳效率可达99.90 %以上,脱酚率可达99%左右,且瞬间完成;膜孔径越小,破乳率越高,膜通量越小;外压内抽方式的破乳效果优于单外压方式的破乳效果。对于粒径为5~2 5 μm乳液,用膜孔径为2 .0 μm的SiC微孔膜,在外压为6 0kPa、内负压为30kPa的外压内抽破乳方式下破乳,破乳率可达96 .4 % ,膜通量可达90 0L·(m2 ·h) -1。 相似文献
48.
酚醛树脂为原料制备双电层电容器用电极材料的工艺研究 总被引:6,自引:2,他引:6
以酚醛树脂为原料,NaOH为活化剂制取双电层电容器用高比表面积活性炭电极材料,考察了炭化温度、活化温度、活化剂用量、活化时间等工艺参数对活性炭比电容的影响。实验结果表明,在炭化温度为600℃,活化温度为900℃,碱炭比为4,活化时间为1h的工艺条件下,制得的高比表面积活性炭比电容可达58.8F/g,用它组装成的电容器具有良好的充放电性能和循环性能,既能在大电流下快速充放电也能在小电流下缓慢充放电,但存在微孔所占比例较高引起的分散电容效应,这是大电流下放电容量有所下降的主要原因。 相似文献
49.
Roser Cervellera Xavier Ramis Josep Maria Salla Ana Mantecn Angels Serra 《应用聚合物科学杂志》2006,102(3):2086-2093
Diglycidyl ether of bisphenol A or 3,4‐epoxycyclohexylmethyl 3,4‐epoxycyclohexane carboxylate were mixed with different proportions of 4‐methyl‐1,3‐dioxolan‐2‐one and cured using lanthanide triflates as initiators. In order to compare the materials obtained, conventional initiators such as boron trifluoride complexes and N,N‐dimethylaminopyridine were also tested. The curing process was followed by differential scanning calorimetry (DSC) and Fourier transform IR in attenuated total reflectance mode. This technique proved that the carbonate accelerates the curing process because it helps to form the active initiating species, although it was not chemically incorporated into the network and remained entrapped in the material. The DSC kinetic study was also reported. © 2006 Wiley Periodicals Inc. J Appl Polym Sci 102: 2086–2093, 2006 相似文献
50.
离子交换膜间水的电离及其应用 总被引:1,自引:0,他引:1
王方 《精细与专用化学品》2002,10(21):22-24
本文通过分析纯水的电离,讨论了普通电渗析(ED)和填充床电渗析(EDI)中水的电离现象及其相关 机理。EDI过程中水电离产生的H+和OH-离子可以自再生离子交换树脂。文中简单介绍了已得到产业化的EDI 技术和正在推广中的离子交换树脂的电再生技术。 相似文献