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Polymer-supported ruthenium complexes Ⓟ-Phen-Ru-①, Ⓟ-Phen-Ru-②, Ⓟ-Phen-Ru-③, Ⓟ-Phen-Ru-④, Ⓟ-Phen-Ru-⑤, Ⓟ-Phen-Ru-⑥ and Ⓟ-Phen-Ru-⑦ were prepared using aminomethyl polystyrenes of different morphological structures as supports. A variety of alcohols were oxidized efficiently into the corresponding ketones, carboxylic acids or aldehydes with iodosylbenzene (PhIO) catalyzed by aminomethyl polystyrene-supported ruthenium complexes under mild reaction conditions in acetonitrile. The influences of morphological structure of the polymer supporters on the catalytic properties of these metal complexes were investigated in detail. 相似文献
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红外光谱研究表明,苯乙烯-丙烯酸共聚物载体-钕络合物具有双配位的羧酸根结构,Nd-O键富有共价性。考察了载体钕络合物催化丁二烯聚合的一般规律,载体钕络合物的组成与聚合活性的关系。在溶剂THF或二氧六环的存在下制得的苯乙烯-丙烯酸共聚物最适宜于合成高活性的载体钕络合物。功能团-COOH含量大约12%,金属钕含量与功能团含量摩尔比在0.20左右的载体钕络合物催化活性最佳。 相似文献
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运用原位FT-IR光谱和TPSR-MS等技术研究了负载Ru催化剂的金属表面状态. 结果表明催化剂中存在二类静态活性中心: (1)体现金属Ru本征特性的S_1中心, (2)金属与载体相互作用而产生的S_2中心. 在吸附CO及其加氢反应过程中, S_1中心上处于边、角、棱位置等配位不饱和的金属Ru原子或原子簇经CO剥蚀而产生的动态S_3活性中心. CO在S_1中心上以Ru~0—CO线式态吸附的, 其IR谱带位于1980~2060 cm~(-1)之间. Ru~0—CO在H_2流中进行程序升温加氢反应的TPSR-MS图上出现450 K左右的低温甲烷峰. 焙烧温度升高, 则在TPSR-MS谱图上出现两个甲烷峰, 600±50 K的高温甲烷峰归属为S_2中心上以Ru~(δ+)-CO线式态吸附CO加氢所致. IR谱图中的2075±50 cm~(-1)峰代表Ru~(δ+)-CO. IR谱中2135±5和2075±5 cm~(-1)这对峰的出现反映了S_3中心的形成. 相似文献
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分子结构对1,2-聚丁二烯橡胶性能的影响 总被引:1,自引:0,他引:1
本文研究了分子链结构、分子量及其分布对钼催化聚合1,2-聚丁二烯(1,2-PB)的加工工艺性能及硫化胶性能的影响.实验发现,1,2-PB的加工工艺行为随分子量降低和分子量分布加宽而得以改善,其抗湿滑性能随分子链中1,2-结构含量增加而提高,而1,2-结构的空间规整性—间同含量的增加则导致1,2-PB应变诱导结晶、降低硫化胶的弹性和增加生热值。 相似文献
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The effect of different kinds of comonomers with or without flexible chain on proper-ties of copolyesters, such as transition temperature, crystallization velocity, crystallinityand size of crystallites, is studied. The experimental results indicate the obvious differ-ence in properties between comonomers with iso- and ortho-structure of phenyl ring andcomonomers with flexible chain. The influence of chemical structure of comonomers onproperties of copolyesters is discussed. 相似文献
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在通过Friedel—Crafts后交联反应制备高度交联聚苯乙烯吸附剂的过程中,向反应体系中加入非极性芳香化合物甲苯,当加入少量甲苯时,吸附剂的比表面积、孔容等变小,但其吸附能力却明显提高;当加入甲苯超过某一量时,其吸附能力又随加入甲苯的量的增加而降低,这说明孔结构和骨架结构共同影响着高度交联聚苯乙烯吸附剂的吸附性能. 相似文献
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Schiff碱配合物结构对其催化氧化性能的影响 总被引:3,自引:0,他引:3
水杨醛缩二胺类双Schif碱配合物,在可逆吸附氧分子和催化氧化性能等方面的研究已有不少报道[1-3]。Schif碱配合物在均相氧化反应中早有应用,但作为异丙苯均相氧化反应的催化剂的报道则很少[4]。已有的研究结果表明,Schif碱配合物结构对在催化氧... 相似文献
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EFFECT OF STRESS-INDUCED REACTIONS ON MORPHOLOGICAL STRUCTURE AND PROCESSABILITY OF PVC DURING PAN-MILLING 总被引:1,自引:0,他引:1
Hua-weiZou WenXu Qing-fenFeng XiXu 《高分子科学》2005,(2):227-234
The effect of pan-milling on morphological structure, processability and properties of PVC was studied through SEM, FTIR, granulometer, GPC and mechanical properties test in the hope of gaining ease in operation, needless of plasticizers, a clean and efficient route for improving the processability of PVC through stress-induced reactions,fulfilling the idea of “plasticizing PVC by itself”. The experimental results show that during pan-milling at ambient temperature, within 2-3 min, the microcrystalline structure of PVC becomes indistinct, the grain size of PVC is reducedfrom 130-160 μm to 1-50 μm the molecular weight of PVC is slightly decreased, the variation of molecular weight distribution is indistinct, the plasticizing time and torque at balance drop a great deal from 71-132 s to 31-33 s and from 18.2-22.1 Nm to 14.7-18.4 Nm, respectively, the processability of PVC is markedly improved, and the mechanical properties get enhanced too. 相似文献
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《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):1361-1368
ABSTRACT The polymer-bound Schiff base ternary cobalt complexes (PS-SalPhe-Co-L (L=Phen, Bipy and 8HQ)) have been prepared from the polymer bound Schiff base ligand, cobalt salt and the second ligand, such as 1,10-phenanthroline(phen), 2,2′-bipyridyl(bipy) and 8-quinolinol(8HQ). The polymer-bound Schiff base ternary cobalt complexes were characterized by the infrared spectra and ICP-AES. The catalytic activity of the complexes has been studied in aerobic epoxidation of long-chain linear aliphatic olefins. It showed that 1-octene or 1-decene can be directly oxidized by molecular oxygen catalyzed by PS-SalPhe-Co-L (L=Phen, Bipy and 8HQ), which afford the 1,2-epoxy alkane. 相似文献
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Transition metal vinylidene complexes (M=C=CHR) have attracted a great deal of attention in recent years as a new type of organometallic intermediates that may have unusual reactivity[1]. Their reactivity has been explored and their application to organic synthesis is developed[2]. Recent reports on the ruthenium-vinylidene complexes[3]suggest that the reaction of ruthenium-vinylidene complexes with a base generates the coordinatively unsaturated ruthenium acetylide species, which are involved in a number of catalytic and stoichiometric reactions of alkynes. For example,the coordinatively unsaturated ruthenium acetylide species C5Me5Ru(PPh3)-C≡CPh,formed from the reaction of the vinylidene complex C5Me5Ru(PPh3) (Cl)=C=CHPh with a base was reactive toward a variety of small molecules and active in catalytic dimerization of terminal alkynes[4]. The dimerization of terminal alkyne is an effective method of forming enynes, but its synthetic application in organic synthesis has been limited dueto low selectivity for dimeric products[5]. In this communication, we report that three ruthenium complexes were used as catalysts for the highly selective dimerization of phenylacetylene. 相似文献
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研究了苯乙烯-丙烯酸共聚物载体-双金属络合物(SAAC·Nd·Na,SAAC·Nd·Fe)的合成以及由其组成的新型丁二烯聚合催化体系.发现在双金属络合物中Nd与游离的-COOH功能团的摩尔比较小时体系的催化活性最佳.对于SAAC·Nd·Fe体系,随着Fe含量的增加活性逐渐下降.对于SAAC·Nd·Na体系,无论Na含量多少都有着促进活性提高的作用,只是在Nd/-COOH摩尔比较小时活性提高较大.此外,初步考察了在邻啡绕啉存在下SAAC·Nd·Fe体系聚合丁二烯的活性以及所得产物的微观结构与络合物SAAC·Nd·Fe中Fe的含量关系. 相似文献
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红外光谱研究表明,苯乙烯-丙烯酸共聚物载体-钕络合物具有双配位的羧酸根结构,Nd-O键富有共价性。考察了载体钕络合物催化丁二烯聚合的一般规律,载体钕络合物的组成与聚合活性的关系。在溶剂THF或二氧六环的存在下制得的苯乙烯-丙烯酸共聚物最适宜于合成高活性的载体钕络合物。功能团-COOH含量大约12%,金属钕含量与功能团含量摩尔比在0.20左右的载体钕络合物催化活性最佳。 相似文献
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IntroductionZSM-5zeoliteshavebeenwidelyemployedinthefieldofhydrocarbonconversion.UtiliZationofMo-containingandKorBamodifiedZSM-5zeolitestOactivatemethaneandtOpreparelightolefinsfromparaffinshavebeenreportedinourpreviouspapersll'2].However,littleattentionh… 相似文献
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lntroductionForthepartialoxidaionofmethanetoformaldehydeacatalystthatfacilitatestheformationofformaldehydewithoutcataIyzingitsfurtheroxidaiontocarbon0xidesisrequired.Effortshavebeenextensivel}'tryingforthisreactionbyusingsilicasupportedmetaloxidesespeciallym0l}'bdenumoxidecataly'stswithdioxygenastheox}'gensourccunderatmosphericconditions.However,mostofthelitefatureresultsshowedvery'l0tvHCH0selectivitiesdcspiteofthehighCH4conversionsandthereforeHCH0yieldsweregenerallybelow2%.Inourpreviousx`… 相似文献