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The effects of ion implantation on ployacetylene films PA have been studied with Ar~+, Fe~+, C1~+, I~+, Na~+ and K~+ ions in the energy range of 15—30 keV. The changes of PA films in the electrical conductivity, due to chemical doping and ion implantation in relation to their structure and depth profiles of impurities, were measured through infrared (ATR/FTIK), Rutherford backscattering spectrometry (RBS) and the four probe technique. In all cases, ion implantation of active ions exhibits the same effects as chemical doping. The formation of p-n junction is observed at the interface of implanted region and chemical doped PA substrate. The mechanism of interaction process between ion beam and polymer is also discussed. 相似文献
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本文研究了乙炔在三异丙醇钕盐[Nd(O-i-Pr)_3]-三烷基铝(AIR_3)-第Ⅲ组份(Ⅲ)络合催化体系中定向聚合的规律。发现在所用稀土络合催化体系中,催化活性不仅与第Ⅲ组份(Ⅲ)添加量有关,而且与铝和钕的摩尔比[AlR_3/Nd(O-i-Pr)_3]有着密切的关系,每种添加剂各有其显示最佳添加效应的铝、钕摩尔比和添加量。同时发现,聚乙炔的顺式含量,除与温度有关外,亦符合上述规律。从而进一步提高了稀土络合催化体系的活性以及聚乙炔膜的顺式含量,在30~5℃制得了高顺式(90—99.5%)具有金属光泽的银色聚乙炔薄膜。此外,本文用红外光谱、顺磁共振、扫描电子显微镜、X衍射、热分析及电阻率、密度测定等对聚乙炔膜进行了表征。 相似文献
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The study on coordination copolymerization of styrene (S) with maleic anhydride (MA) by rare-earth coordination catalysts, NdL_3-Al(i-Bu)_3, has been successfully carried out for the first time. Some features, kinetic behavior, and mechanism of the SMA copolymerization by Nd(naph)_3-Al(i-Bu)_3 system are described and discussed. The copolymex of styrenemaleic anhydride prepared by the NdL_3-Al(i-Bu)_3 systems in benzene at 50℃ is an alternating-rich white powder having high number-average molecular weight of 6—8.5×10~5. The overall activation energy for the polymerization was found to be 10.5KJ/mol. The polymerization was not suppressed by addition of hydroquinone. The catalytic activity of various ligands in NdL_3 for the copolymerization decreases in the following order: Nd (naph)_3>Nd-(P_(507))_3~NdCl_3-6H_2O>Nd(P_(204))_3>Nd(acac)_3. 3H_2O. The experimental results are explained based on a mechanism to be the coordination-type copolymerization in terms of the participation of a monomer-monomer c 相似文献
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Epichlorohydrin (ECH) was polymerized with a rare earth catalytic system: Nd (i-OPr)_3-Al (i-Bu)_3. The effects of Al/Nd molar ratio, solvents, the polymerization time and temperature,the aging time and temperature of the catalyst preparation were studied. The results showed thatat a low Al/Nd molar ratio (4) of the Nd(i-OPr)_3-Al(i-Bu)_3 system ECH polymerized at a lowtemperature (248K) with a high conversion. The average molecular weight ofpolyepichlorohydrin (PECH) ranged from 1×10~5 to 3×10~5. 相似文献
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Polyacetylene is the most hopeful electrical conductive polymer, which is being exploited to fabricate plastic battery, solar energy cell etc. The catalysts used for the synthesis of high cis-polyacetylene films are mainly Ti(OC_4H_9)_4-AlEt_8 and rare-earth coordination catalysts as well as Co(NO_3)_2-NaBH_4. This paper reports features of acetylene polymerization by novel catalysts composed of transition metal 2-ethyl hexyl phosphonates of the fourth periodic transitional series-Ti, V, Cr, Mn, Fe, Co, Ni and aluminium trialkyls. Except Ni catalyst system, all catalytic systems can promote polymerization of acetylene at room temperature to form a silvery-grey polyacetylene film with rich cis-content and high crystallinity. Under the experimental conditions tested, the catalytic activity of various systems shows the following sequence: Fe>Ti~V>Cr>Mn>Co>Ni The polyacetylene films obtained were characterized. 相似文献
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离子液体支载稀土催化剂催化 2,2-二甲基-三亚甲基碳酸酯均聚及其与ε-己内酯的共聚 总被引:1,自引:0,他引:1
首次合成了离子液体支载稀土催化剂,并探讨了其催化2,2-二甲基-三亚甲基碳酸酯(DTC)均聚及其与ε-己内酯(ε-CL)的共聚,结果表明该新型催化剂能有效地催化DTC的均聚及其与ε-CL的共聚.研究了不同稀土以及加料顺序等反应条件对聚合的影响,发现轻稀土的催化活性比重稀土高,其中离子液体支载La催化剂的催化活性最高,而通过控制不同的加料顺序可以制备DTC和ε-CL的无规及嵌段共聚物.对共聚物结构进行了表征. 相似文献
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取代茚基稀土配合物/添加剂体系催化丙烯腈聚合 总被引:7,自引:1,他引:7
研究了取代茚基稀土配合物 /添加剂体系对丙烯腈的聚合 ,发现季胺盐及芳氧钠是取代茚基二价稀土配合物催化丙烯腈聚合的有效添加剂 ,其中Me3NC1 6 H33Br效果最好 ,5种二价稀土配合物 (C5H9C9H6 ) 2 Yb (THF) 2 ,(C5H9C9H6 ) 2 Sm (THF) 2 ,KSm (C5H9C9H6 ) 3(THF) 3,(PhCH2 C9H6 ) 2 Sm(THF) 2 和 (CH3CH2 C9H6 ) 2 Sm (THF) 2 与Me3NC1 6 H33Br构成的催化体系对于丙烯腈聚合都显示出好的催化活性。对(C5H9C9H6 ) 2 Yb(THF) 2 /Me3NC1 6 H33Br体系而言 ,在丙烯腈中当催化剂用量为 2× 10 - 5mol·g - 1时 ,丙烯腈聚合的最大转化率为 61%。 相似文献