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1.
李长元  罗炎 《应用化学》2005,22(10):1104-0
无孔双马来酰亚胺树脂微球的制备;聚醚酰亚胺;双马来酰亚胺树脂;相结构;微球  相似文献   

2.
双马来酰亚胺在改进硅橡胶热稳定性中的作用   总被引:2,自引:0,他引:2  
 双马来酰亚胺能改进硅橡胶在空气或氧气中的热稳定性。热老化试验和热降解动力学分析表明,其机理可能是双马来酰亚胺能优先与氧作用,避免了硅橡胶链上侧甲基被氧化,减轻了交联密度的提高,从而提高了硅橡胶的热稳定性。  相似文献   

3.
氢化松香是重要的天然可再生资源松香的深加工产品之一,在电子、食品、医药等领域有着重要的用途。本文介绍了氢化松香的主要组分、氢化松香国内外工业化生产历程及氢化松香制备工艺,特别是由贵金属钯和非贵金属镍为催化剂的制备工艺的研究现状;对近年来氢化松香和二氢枞酸衍生物,主要是以氢化松香为整体的衍生物的制备研究进行了综述,并对氢化松香及其衍生物研究前景进行了展望。  相似文献   

4.
bmi/bce树脂体系反应固化动力学研究   总被引:5,自引:0,他引:5  
氰酸酯;双马来酰亚胺;反应机理;固化动力学  相似文献   

5.
聚合松香的制备及其含量测定   总被引:4,自引:0,他引:4  
以工业松香为原料,用硫酸-无水氯化锌作催化剂制备聚合松香.在70℃下,用甲苯溶解松香(松香和甲苯的重量比为1∶1),加入n(H2SO4)∶n(ZnCl2)=0.6的催化剂,120℃温度聚合反应10 h和270℃减压蒸馏(200 Pa)的条件下,所得一级聚合松香的二聚松香的含量≥90.5%,软化点182℃,酸值150.6 mg KOH/g,收率≥74%;二级聚合的二聚松香的含量≥65%,软化点135℃,酸值157 mg KOH/g,收率≥95%.用GC-MS分离出二聚体中的14个异构体;通过测定松香单体和二聚体的相对校正因子,采用面积归一法测定产品二聚体的含量.  相似文献   

6.
合成了一系列结构不同和链长短不一的双马来酰亚胺,并对其结构和性能作了表征,同时研究了它们的固化反应和固化产物的性能。用双马来酰亚胺和二烯丙基化合物反应制造了增韧树脂,研究了该树脂的固化和热稳定性。  相似文献   

7.
松香树脂酸乙烯酯合成新方法   总被引:2,自引:0,他引:2  
松香树脂酸乙烯酯合成新方法哈成勇袁金伦夏建汉(中国科学院广州化学研究所广州510650)松香树脂酸及其衍生物的乙烯酯是一类含活性乙烯基的物质;歧化松香树脂酸乙烯酯[主要成分为去氢枞酸乙烯酯(简称VDeHA)和二氢枞酸乙烯酯(简称VDiHA)]和马来海...  相似文献   

8.
催化加氢;反应机理;氢化松香;Raney镍催化松香加氢反应的机理  相似文献   

9.
邓瑞红  余政  张招贵 《应用化学》2012,29(4):486-488
以天然松香为原料,通过胺化、脱水、Diels-Alder反应合成一种新型松香衍生物马来松香腈。考察了反应温度、反应时间和物料配比等因素对产率的影响,得到了较佳的合成条件。用IR、1H NMR和MS方法对其结构进行了表征。  相似文献   

10.
松香改性制备表面活性剂及其应用研究进展   总被引:5,自引:0,他引:5  
从松香出发,可制备阴离子、阳离子、非离子和两性离子等四类表面活性剂。文章综述了国内外近年来以松香和改性松香为主要原料合成表面活性剂及其应用方面的研究进展,分别讨论了这些表面活性剂在使用过程中的主要优势和存在问题。  相似文献   

11.
From a methanol extract of Artemisia caruifolia, which showed a moderate inhibitory activity on HIV-1 protease in a preliminary screening, N1,N5,N10-tri-p-coumaroylspermidine and three dicaffeoylquinic acids were isolated. The former compound was found to appreciably inhibit HIV-1 protease. Of related amides which were chemically synthesized, N1,N5,N10,N14-tetra-p-coumaroylspermine and N1,N4,N7,N10,N13-penta-p-coumaroylte-traethylenepentamine inhibited HIV-1 protease more potently than N1,N5,N10-tri-p-coumaroylspermidine.  相似文献   

12.
本文合成了4种新型不对称酰胺荚醚萃取剂:N,N′-二甲基-N,N′-二苯基-3-氧戊二酰胺(DMDPhDGA)、N,N′-二甲基-N,N′-二己基-3-氧戊二酰胺(DMDHDGA)、N,N′-二甲基-N,N′-二辛基-3-氧戊二酰胺(DMDODGA)、N,N′-二甲基-N,N′-二癸基-3-氧戊二酰胺(DMDDDGA)。以氯仿为稀释剂,研究了N,N,N′,N′-四丁基-3-氧戊二酰胺(TBDGA)及上述4种萃取剂从硝酸体系中萃取Gd(Ⅲ)的反应机理,得出萃取能力顺序为:DMDHDGA>DMDDDGA>DMDODGA>DMDPhDGA>TBDGA。考察了水相酸度和萃取剂浓度对萃取分配比的影响,得出萃合物中有3个萃取剂分子同时参与配位;并结合红外光谱解释了萃取剂结构与萃取性能的关系。  相似文献   

13.
王世范 《合成化学》2001,9(3):223-226
合成了新型氮功能化大环配体内消旋-5,5,7,12,12,14-六甲基-1,4,8,11-四氮杂环十四烷-N,N'-二乙酸乙酯(TETADE);内消旋-5,5,7,12,12,14-六甲基-1,4,8,11-四氮杂环十四烷-N,N',N',N'',N'''-四乙酸乙酯(TETADE);内消旋-5,5,7,12,12,14-六甲基-1,4,8,11-四氮杂环十四烷-N,N'-二乙酸(TETADA);内消旋-5,5,7,12,12,14-六甲基-1,4,8,11-四氮杂环十四烷-N,N',N',N'''-四乙酸(TETATA)和内消旋-5,5,7,12,12,14-六甲基-1,4,8,11-四氮杂环十四烷-N,N'-二异羟肟酸(TETAD-HA).均通过元素分析、IR,1H NMR和MS表征.  相似文献   

14.
Synthesis, Structure, and some Reactions of N-(N′,N′,N″,N″-tetramethyl)guanidinyl-substituted Phosphoryl Compounds The tetramethylguanidinyl-substituted phosphoryl compounds 1 – 10 were prepared in the reaction of the appropriate chlorophosphoryl compounds with either N′,N′,N″,N″-tetramethylguanidine (HTMG) or N-trimethylsilyl-(N′,N′,N″,N″-tetramethyl)guanidine (TMSTMG). With methyl iodide 1 reacted with N-alkylation to give the ammonium salt 11. 1 reacted with BF3 · Et2O at both imino nitrogen atoms with formation of the bis-BF3-adduct 12 . The X-ray structure determination of phenylphosphonic acid-bis(N′,N′,N″,N″-tetramethylguanidinide) 3 shows shortened PN-bonds and widened PNC-angles, consistent with the partial double bond character of the PN-bond.  相似文献   

15.
锰(Ⅱ)呋喃甲醛Schiff碱催化苯乙烯环氧化的研究   总被引:1,自引:0,他引:1  
自1979年Groves首先以金属卟啉模拟细胞色素P-450,实现烯烃的环氧化^[1]以来,仿单加氧酶催化环氧化烯烃就成为仿酶催化领域里的一个非常活跃的研究课题^[2-5],但在这些报道中所用的模型化合物均为金属卟啉及其衍生物或Mn-Salen及其衍生物,这些化合物高昂的价格极大地限制了其应用前景。呋喃甲醛(俗称糠醛)取之于米糠或玉米芯,价格便宜且非石化产品,用它取代水杨醛不仅可降低成本,而且符合绿色化学要求。为此,本文选取了五种锰呋喃甲醛Schiff碱配合物作为模型化合物,以NaOCI为氧化剂,催化苯乙烯环氧化。讨论了配体结构、氧化物的pH值、轴配体、反应时间对催化环氧化反应的影响。  相似文献   

16.
Adenosine (Ado) can accept three protons, at N1, N3, and N7, to give H(3) (Ado)(3+) , and thus has three macro acidity constants. Unfortunately, these constants do not reflect the real basicity of the N sites due to internal repulsions, for example, between (N1)H(+) and (N7)H(+). However, these macroconstants are still needed for the evaluations and the first two are taken from our own earlier work, that is, pK(H)(H(3))((Ado)) = -4.02 and pK(H)(H(2))((Ado)) = -1.53; the third one was re-measured as pK(H)(H)((Ado)) = 3.64 ± 0.02 (25 °C; I=0.5 M, NaNO(3)), because it is the main basis for evaluating the intrinsic basicities of N7 and N3. Previously, contradicting results had been published for the micro acidity constant of the (N7)H(+) site; this constant has now been determined in an unequivocal manner, and that of the (N3)H(+) site was obtained for the first time. The micro acidity constants, which describe the release of a proton from an (N)H(+) site under conditions for which the other nitrogen atoms are free and do not carry a proton, decrease in the order pk(N7-N1)(N7(Ado)N1·H)) = 3.63 ± 0.02 > pk(N7-N1)(H·N7(Ado)N1) = 2.15 ± 0.15 > pk(N3-N1,N7)(H·N3(Ado)N1,N7) =1.5 ± 0.3, reflecting the decreasing basicity of the various nitrogen atoms, that is, N1>N7>N3. Application of the above-mentioned microconstants allows one to calculate the percentages (formation degrees) of the tautomers formed for monoprotonated adenosine, H(Ado)(+) , in aqueous solution; the results are 96.1, 3.2, and 0.7% for N7(Ado)N1·H(+), (+)H·N7(Ado)N1, and (+)H·N3(Ado)N1,N7, respectively. These results are in excellent agreement with theoretical DFT calculations. Evidently, H(Ado)(+) exists to the largest part as N7(Ado)N1·H(+) having the proton located at N1; the two other tautomers are minority species, but they still form. These results are not only meaningful for adenosine itself, but are also of relevance for nucleic acids and adenine nucleotides, as they help to understand their metal ion-binding properties; these aspects are briefly discussed.  相似文献   

17.
从N,N’-二烷基酯联咪唑出发,经过还原、氯代、亲核取代反应,合成了N,N’-二烷基膦联咪唑.产物经过了红外、核磁共振及质谱表征.反应前体N,N’-二醇联咪唑和N,N’-二烷基氯联咪唑可作为起始物,合成得到一系列联咪唑衍生物.  相似文献   

18.
The N–N bond is present in many important organic compounds, such as hydrazines, pyrazoles, azos, etc. Many methods based on transition metal catalyzed N–N coupling or functionalization of hydrazine have been reported for the synthesis of N–N containing organic compounds. In recent years, electrochemical dehydrogenative N–H/N–H coupling has become a powerful tool for the construction of N–N bearing organic compounds. The electrochemical methods employ electrons as traceless redox reagents instead of chemicals and produce hydrogen as the only byproduct. In this review, we summarize the recent advances in the electrochemical dehydrogenative N–H/N–H coupling reactions with focus on the mechanistic insights and synthetic applications of these transformations.  相似文献   

19.
If a strong base is added to solutions containing complexes of trivalent antimony with aminopolycarboxylates, these ligands are displaced, and oversaturated solutions of antimony (III) hydroxide are formed. This reaction has been used to investigate the formation of complexes of SbIII with the following ligands: N′-hydroxyethyl-ethylenediamine-N,N,N′-triacetate ion, ethylenediamine-N,N,N′,N′-tetraacetate ion, 1,2-diaminocyclohexane-N,N,N′,N′-tetraacetate ion, and diethylenetriamine-N,N,N′,N″,N″-pentaacetate ion.  相似文献   

20.
无烟煤挥发分和焦炭独立燃烧过程中NO生成规律   总被引:2,自引:1,他引:1  
采用固定床反应器,将无烟煤粉的燃烧分为焦炭燃烧和挥发分燃烧两部分,研究了各自燃烧过程中产生NO的规律,评价了焦炭N和挥发分N对煤粉燃烧产生NO的相对贡献。结果表明,煤粉N﹑焦炭N和挥发分N的转化率都随过量空气系数α和温度的增加而增加;焦炭N是无烟煤粉燃烧过程中NO的主要来源;煤粉的转化率都小于煤粉分解燃烧时挥发分转化率加焦炭的总转化率;还原性气氛或氧化性气氛越强,挥发分和焦炭在煤粉燃烧时的相互作用越强。  相似文献   

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