共查询到20条相似文献,搜索用时 406 毫秒
1.
2.
3.
4.
以2,4-二异氰酸甲苯酯(2,4—TDI)、胆甾醇、丙烯酸β-羟丙酯为原料,合成了含胆甾醇介品基团的侧链液晶高分子、并用NMR、IR和元素分析方法对其结构进行了鉴定。聚合物的相转变温度和形态织构用DSC、X-射线衍射和偏光显微镜进行了测定和观察。 相似文献
5.
PS/LDPE共混体系相结构的TEM研究徐世爱,江明,沈静姝(复旦大学高分子科学系和聚合物分子工程实验室,上海,200433)(中国科学院化学研究所高分子物理开放实验室)关键词相结构,透射电镜,共混体系聚苯乙烯(PS)和低密度聚乙烯(LDPE)共混体... 相似文献
6.
PS/LDPE共混体系形变机理的TEM研究徐世爱,江明(复旦大学高分子科学系、聚合物分子工程实验室,上海,200433)沈静姝(中国科学院北京化学所高分子物理开放实验室)关键词形变机理,银纹,透射电镜,共混物在PS/LDPE共混体系中加入接枝或嵌段共... 相似文献
7.
8.
负载型SiO2无机膜的制备与表征 总被引:1,自引:0,他引:1
采用Sol-Gel法制备负载型SiO_2无机膜,考察了有机粘结剂、处理温度对膜性能和结构的影响,并用SEM、XRD、孔分布和渗透性测定等方法对无机膜进行了表征。 相似文献
9.
以4-苯乙烯基吡啶(4SZ)为质子受体,准链链含苯甲酸的苯乙烯/马来酸单楷共聚物(ME-SMA)为质子供体,四氢呋喃为溶剂,制备高分子氢链复合物。DSC和POM的结果表明该氢链复合物在146 ̄204℃呈现向列相液晶态。IR结果证实了羧基和吡啶环的分子间氢键代替了羧基间的分子间氢链。 相似文献
10.
利用DSC、DMA、TEM和XPS对[PSF-PDMS-PHS]n/PSF共混物的相容性及表面组成进行了研究.结果表明,PDMS在共混物表面的富集与PSF均聚物和[PSF-PDMS-PHS]n中硬段的相容性有关;PDMS在相容的共混物体系表面的富集与对应的多嵌段共聚物组成基本相近;不相容共混物体系表面PDMS的富集程度相对较高,当共混物本体中有机硅含量从1%增至5%,表面层PDMS的含量迅速增加,可达到嵌段共聚物中PDMS的含量. 相似文献
11.
12.
13.
14.
A low barrier in the reaction pathway between the double Rydberg isomer of OH(3) (-) and a hydride-water complex indicates that the former species is more difficult to isolate and characterize through anion photoelectron spectroscopy than the well known double Rydberg anion (DRA), tetrahedral NH(4) (-). Electron propagator calculations of vertical electron detachment energies (VEDEs) and isosurface plots of the electron localization function disclose that the transition state's electronic structure more closely resembles that of the DRA than that of the hydride-water complex. Possible stabilization of the OH(3) (-) DRA through hydrogen bonding or ion-dipole interactions is examined through calculations on O(2)H(5) (-) species. Three O(2)H(5) (-) minima with H(-)(H(2)O)(2), hydrogen-bridged, and DRA-molecule structures resemble previously discovered N(2)H(7) (-) species and have well separated VEDEs that may be observable in anion photoelectron spectra. 相似文献
15.
16.
17.
Summary Dichlorobis(methylsalicylato)titanium(IV) reacts with potassium or amine salts of dialkyl or diaryl dithiocarbamates in 11 and 12 molar ratios in anhydrous benzene (room temperature) or in boiling CH2Cl2 to yield mixed ligand complexes: (AcOC6H4O)2 Ti(S2CNR2)Cl (1) and (AcOC6H4O)2 Ti(S2CNR2)2 (2), R=Et, n-Pr, n-Bu, cyclo-C4H8 and cyclo-C5H10. These compounds are moisture sensitive and highly soluble in polar solvents. Molecular weight measurement in conjunction with i.r.,1H and13C n.m.r. spectral studies suggest coordination number 7 and 8 around titanium(IV) in (1) and (2) respectively. 相似文献
18.
Pure, highly explosive CF(3)C(O)OOC(O)CF(3) is prepared for the first time by low-temperature reaction between CF(3)C(O)Cl and Na(2)O(2). At room temperature CF(3)C(O)OOC(O)CF(3) is stable for days in the liquid or gaseous state. The melting point is -37.5 degrees C, and the boiling point is extrapolated to 44 degrees C from the vapor pressure curve log p = -1875/T + 8.92 (p/mbar, T/K). Above room temperature the first-order unimolecular decay into C(2)F(6) + CO(2) occurs with an activation energy of 129 kJ mol(-1). CF(3)C(O)OOC(O)CF(3) is a clean source for CF(3) radicals as demonstrated by matrix-isolation experiments. The pure compound is characterized by NMR, vibrational, and UV spectroscopy. The geometric structure is determined by gas electron diffraction and quantum chemical calculations (HF, B3PW91, B3LYP, and MP2 with 6-31G basis sets). The molecule possesses syn-syn conformation (both C=O bonds synperiplanar to the O-O bond) with O-O = 1.426(10) A and dihedral angle phi(C-O-O-C) = 86.5(32) degrees. The density functional calculations reproduce the experimental structure very well. 相似文献
19.