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1.
Thermal oxidation of polyethylene containing amine and phenolic antioxidants during contact with copper (metal support, powder) and the trends in variation of the antioxidant performance were studied.  相似文献   

2.
A study has been made on samples of dispersed vanadium dioxide (VO2) in a matrix of polyethylene glycol (PEG) doped with a quaternary ammonium salt (QAS), namely tetraethylammonium bromide. It has been established that under the influence of the dopant the heating of a sample up to the temperature of the metal-semiconductor phase transition (MSPT) results in a phase in homogeneity of the sample. On the basis of the results of this study it is possible to conclude that small concentrations of QAS in a PEG matrix can exert a strong effect on the electronic structure of dispersed VO2 particles. This is accompanied by the appearance of phase heterogeneity of VO2 which manifests itself in the fact that - with the onset of MSPT with increasing temperature - one portion of the substance passes into the metallic state, and the other remains in the semiconductive state. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

3.
Contact oxidation of polyethylene films on copper was studied as influenced by their thickness. An oxidation mechanism is proposed.  相似文献   

4.
Transfer of metal into the polymer bulk during contact oxidation of polyethylene films on a copper support was studied. The metal distribution in the sol and gel fractions of the polymer was determined.  相似文献   

5.
Conducting composite systems containing polypyrrole layers were prepared by in situ polymerization of pyrrole on the surface of porous polyethylene films. The polymerization was performed in the gas phase, in a monomer solution, and in supercritical CO2. The chemical structures, electrical conductivities, and mechanical, thermodeformational, and morphological characteristics of the composites obtained were compared.  相似文献   

6.
利用透射电子显微学(TEM)和示差扫描量热学(DSC)等方法研究了含少量丁烯-1组分(摩尔分数为0.64%)的聚乙烯共聚物(PE100)熔体拉伸高取向薄膜的形态结构. 结果表明, 在PE100熔体拉伸薄膜中, 除存在高取向片晶结构外, 还含有大量的纤维晶, 纤维晶平行于拉伸方向, 穿过几个片晶区, 平均直径约为12 nm. 模拟实验结果表明, 纤维晶的生成源于聚乙烯共聚物中的超高分子量组分, 但不同于传统意义上的伸直链纤维晶, 其形态特征应为晶桥结构. 由此提出了晶桥结构纤维晶模型, 该模型不但有助于深入理解和认识聚合物取向结晶机理, 同时也为该材料的高性能化提供了理论依据.  相似文献   

7.
The conducting properties of composites prepared by deposition of polyaniline layers on the surface of porous polyethylene films from dispersions and by polymerization in situ were studied.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 3, 2005, pp. 484–489.Original Russian Text Copyright © 2005 by Kuryndin, Mokreva, Terlemezyan, Sidorovich, Praslova, Elyashevich.  相似文献   

8.
杯芳烃;合成;杯[4]芳烃-受阻胺类复合稳定剂在聚丙烯中的抗热氧稳定性能  相似文献   

9.
10.
We report a systematic study on wrinkling and CuO nanowires (NWs) growth in the thermal oxidation of copper foil. Copper foils with thickness of 0.5 mm were thermally oxidized in air at 500℃ for 0.5-10 h. It is found that all the samples have wrinkles and the size of the wrinkles increases with the oxidation time increasing. CuO NWs can grow on both the sidehill and hilltop of wrinkle. The CuO NWs on sidehill are longer and denser than those on hilltop. The growth direction of the CuO NWs on sidehill is not vertical to the substrate but vertical to their growth surfaces. The process of wrinkling and CuO NWs growth can be divided into three stages: undulating, voiding, and cracking. The CuO NWs on both sidehill and hilltop grow at the undulating stage. However, only the CuO NWs on sidehill grow and those on hilltop stop growing at the voiding and cracking stages because of the void in hilltop. The local electric field in a wrinkle at undulating stage was calculated, and it is found that the difference of local electric field strengths between hilltop and sidehill is small, which indicates that the predominant driving force for the diffusion of Cu ion during CuO NWs growth is internal stress.  相似文献   

11.
松香和枞酸在聚乙烯膜上氧化反应动力学研究   总被引:1,自引:0,他引:1  
设计了松香和枞酸在聚乙烯膜上的氧化反应器, 建立了枞酸在聚乙烯膜上的紫外分光光度分析方法, 跟踪测定了松香和枞酸氧化反应的过程. 实验结果表明, 松香和枞酸的氧化反应均呈现表观一级反应. 枞酸的氧化反应温度为30, 35, 40, 45, 50和55 ℃时, 表观速率常数分别为0.0036, 0.0041, 0.0062, 0.0087, 0.011和0.0157 min-1, 表观反应活化能Ea为50.29 kJ/mol. 松香的氧化反应温度为35, 40和45 ℃时, 表观速率常数分别为0.0009, 0.0015和0.0025 min-1 , 表观反应活化能Ea为80.2 kJ/mol.  相似文献   

12.
光/生物降解聚乙烯薄膜的光降解性能   总被引:10,自引:0,他引:10  
光/生物降解聚乙烯薄膜的光降解性能;淀粉;聚乙烯;塑料薄膜;降解性能  相似文献   

13.
2,2,2-三硝基乙基-N-硝基甲胺的热安全性   总被引:1,自引:0,他引:1  
为评价2,2,2-三硝基乙基-N-硝基甲胺(TNMA)的热安全性, 得到计算TNMA热安全性参数用的基本数据, 用经验式估算了TNMA的比热容(Cp)和热导率(λ). 用键能贡献于生成热Qf的加和法, 估算了TNMA的标准生成焓ΔcHmθ(TNMA, s, 298.15 K). 用热力学公式计算了TNMA的标准燃烧焓ΔUmθ(TNMA, s, 298.15 K)和标准燃烧能ΔcHmθ(TNMA, s, 298.15 K). 用Kamlet-Jacobs 公式估算了爆速、爆压和爆热. 用经验式估算了分解热(Qd). 通过差示扫描量热(DSC)曲线和高灵敏度布鲁顿玻璃薄膜压力计测得的逸出气体标准体积(VH)-时间(t)曲线, 得到了TNMA放热分解反应的动力学参数. 用上述基本数据得到了评价TNMA的热安全性参数: 自加速分解温度(TSADT), 热爆炸临界温度(Tbe0和Tbp0), 绝热至爆时间(tTIad), 撞击感度50%落高(H50), 热点起爆临界温度(Tcr), 被300 K环境包围的半厚和半径为1 m的无限大平板、无限长圆柱和球形TNMA的热感度概率密度函数S(T), 相应于S(T)-T关系曲线最大值的峰温(TS(T)max), 安全度(SD), 临界热爆炸环境温度(Tacr)和热爆炸概率(PTE). 结果表明: (1) TNMA有较好的热安全性和对热抵抗能力, 与环三亚甲基三硝胺(RDX)相比, TNMA易从热分解过渡到热爆炸; (2) 不同形状大药量TNMA 热安全性降低的次序为: 球>无限长圆柱>无限大平板; (3)TNMA有高的燃烧能、高的爆轰化学能(爆热)和接近环四亚甲基四硝胺(HMX)的爆炸性能, 其对冲击敏感, 冲击感度与季戊四醇四硝酸酯(PETN)和特屈尔接近, 可用作混合炸药主组分.  相似文献   

14.
Reaction of copper halides CuX (X=Cl, Br, I) with tri(2‐pyridylmethyl)amine) (TPMA) in THF under N2 affords a series of monomeric copper(I) complexes CuX(TPMA) (X=Cl ( 1 ), Br ( 2 ) and I ( 3 )). Treatment of [CuCl(TPMA)] ( 1 ) with 0.5 equivalent of 1,4‐diisocyanobenzene following by equimolar amount of NaBF4 affords a novel binuclear complex [(TPMA)Cu(μ‐1,4‐CNC6H4NC)Cu(TPMA)](BF4)2 ( 4 ). The copper(I) halide TPMA complexes show interesting fluxional behaviors in temperature dependence in the 1H NMR spectrum that can be explained by the dissociation and reassociation of the pyridyl group and alkylamine nitrogen of TPMA ligand. The crystal structures of 1 , 3 and 4 are determined by an X‐ray diffractometer. Complexes 1 and 3 are distorted tetrahedral coordinates with strong bonding between three pyridyl N atoms and the corresponding halide donor. Crystallographic results of 4 clearly indicates two Cu(I) ions are bridged by 1,4‐diisocyanobenzene, forming a centro‐symmetrical homobinuclear complex with a “dangling” uncoordinated pyridyl group.  相似文献   

15.
王少敏  于九皋 《应用化学》2003,20(11):1080-0
高分子吸附剂;仲胺型硝化纤维素的合成及应用  相似文献   

16.
Copper aryl carboxylates are known to form co-ordination complexes with various nitrogen donors1-4). Except copper (II) benzoate5) complexes of other copper (II) aryl carboxylates with secondary amines such as diethyl amine and dipropyl amine are not known. The present communication deals with the preparation of complexes of various copper (II) aryl carboxylates with diethyl amine and dipropyl amine.  相似文献   

17.
The catalytic activity of soot filters for internal combustion gas exhausts made from synthetic cordierite with a catalytic covering of transition metal oxides (Co3O4, MnO2, CuO, Cr2O3) or binary oxides (CuCr2O4, CuCo3O5, Co3MnO6, CuMnO3) has been studied. The most active catalyst for the oxidation of CO and hexane and for the combustion of soot forming compounds in the exhaust gases is copper chromite. A secondary carrier based on -Al2O3 increased the soot capacity of the filters and increased the selectivity the process of combustion of soot to CO2.  相似文献   

18.
Allene groups are first employed as the reactive moiety in the simple and efficient synthesis of well‐defined functional polyethylene. By copolymerization of ethylene with allene group substituted norbornene, the allene group is successfully introduced into the polyethylene with a high content. The retained allene groups are demonstrated to be highly reactive in following photoinduced functionalized reactions and can be efficiently converted into the functional groups without the multi‐step, time consuming processes that have generally been required in previous reports, providing the side group‐functionalized polyethylene with a wide range of functional group content.  相似文献   

19.
Au nanoparticles dispersed ZrO2 thin films were prepared from two precursors HAuCl4·4H2O and ZrOCl2·8H2O in air. The structural properties and size of Au particle in ZrO2 film were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The surface analysis with atomic force microscopy (AFM) showed the effect of monoethanolamine on preventing the migration of Au particles to the surface. The absorption peak of Au particles by the surface plasma resonance was observed and the red shift of absorption peak was discussed.  相似文献   

20.
曾苏伟  徐森  王勇  喻敏  朱荔  姚小泉 《有机化学》2015,35(4):827-834
以铜纳米颗粒作为催化剂,Cs2CO3为碱,二卤甲烷为底物和溶剂,发展了一个高效的催化炔、二卤甲烷、胺三组分偶联反应(AHA偶联反应)生成炔丙胺的反应体系.与文献相比,该催化体系具有催化剂廉价易得、反应条件相对温和、底物适应性优良、使用单一溶剂体系后处理方便的特点.同时,以铜纳米颗粒为催化剂,易于实现催化剂的有效循环利用,经5次反应催化活性未见明显下降.  相似文献   

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