共查询到19条相似文献,搜索用时 62 毫秒
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The easily accessible, water soluble, conjugated polymer poly(4-bromopyridine), has been synthesised by the self-condensation of 4-bromopyridine at various temperatures and also in the presence of methyl iodide. The structure of the material is complex with a variety of sub-units; possible structures are discussed in the light of a detailed spectroscopic analysis. 相似文献
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以Pd2(dba)3作为催化剂,对2-溴吡啶和4-氟苯硼酸进行了Suzuki偶联反应,合成了相应的偶联产物2-(4-氟苯基)吡啶,并利用单因素法考查了反应中所用的碱、溶剂、相转移催化剂等因素对反应的影响,探索其最佳反应条件。最佳反应条件是碱为KOH,溶剂为水,相转移催化剂为十六烷基三甲基溴化铵。 相似文献
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含氟丙烯酸酯聚合物具有许多特殊优异性能,成为新型含氟材料领域研究热点。在许多要求特殊性能领域获得广泛应用,如特殊涂料、纸张和皮革涂饰剂、织物整理剂等。阐述了含氟丙烯酸酯类单体合成技术进展,并对其研究开发提出一些建议。 相似文献
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研究了2,6-二叔丁基对苯醌的合成工艺,选择了最佳合成方法,即催化分子氧氧化法,该法以2,6-二叔丁基苯酚和氧气为原料,采用自制催化剂,进行气液相氧化,通过多次对比实验,确定了最佳催化剂用量和产品提纯方法,产品收率为70%,纯度大于99.5%。 相似文献
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?brahim Uslu Tuncay Tun? 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(1):183-189
In this study, polyvinyl alcohol (PVA) and boric acid (BA) were mixed in an aqueous medium by heating in order to prepare
a PVA/BA hybrid material. The viscosity and pH values of the PVA/BA hybrid material mixed in various proportions were determined.
Then the hybrid polymer was electrospun to give dimensions to fibers. The FT-IR spectra of these fibers revealed that BA chemically
reacted with PVA and formed B–O–C bonds. The fibers were first calcified at 500 °C and then the calcified products were pelleted
and exposed to the sintering process at 1300 °C. The XRD peaks of the sintered product were seen at 2θ = 34.7 and 37.7° verified
the formation of boron carbide. The study proved that it was possible to use sub-micron fibers for the production of sub-micron
boron carbide material. 相似文献