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A series of new optically active aromatic poly(ester arnide)s containing a chiral group in the side chain prepared from the p-toluenesulfonic acid salt of o,o‘-bis(leucyl)-hexanediol (TS^- LHD^ TS^-) and p-phthaloyl chloride and styrene-2,5-dicarbonyl chloride styrene have been synthesized by interfacial polymerization. The structure of the monomer is elucidated by FT-IR and elemental analysis. The thermal properties of the polymers were studied by DSC and TGA. The chiroptical properties of the above polymer have also been studied by circular dichroism (CD) spectroscopy. Results indicated that these polymers form helical structures. 相似文献
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Effect of both structure of substituents and degree of substitution of polyions derived from poly-vinyl alcohol on water-absorbility and antithrombogenecity of formed polyionic complexes (PIC)have been investigated. It was found that the water content of the PIC formed from p-formylben-zenesulfonic acid substituted PVA was higher than that of the PIC formed from p-formylbenzoicacid substituted PVA. When the substitution degree of polycation increased from 27% to 64%,the water content of the formed PIC increased from 170% to 1270%. Effect of water content andnet charge of PVA-type PIC on the antithrombogenecity was also investigated by plasma recalci-fication method. 相似文献
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KhalilFaghihi AzizollahMirsamie 《高分子科学》2005,(1):63-69
Eight novel poly(amide-imide)s were synthesized under microwave irradiation by using a domestic microwaveoven from the polycondensation reactions of N,N′-(pyromellitoyl)-bis-L-alanine diacid chloride (1) with eight different derivatives of hydantoin compounds (2a-h) in the presence of a small amount of a polar organic medium such as o-cresol. The polycondensation proceeded rapidly, compared with the conventional solution polycondensation and was completed within 8-10min, producing a series of new poly(amide-imide)s (3a-h) with inherent viscosities about 0.35-0.68dL/g in high yields. The obtained PAIs (3a-h) were fully characterized by means of FT-IR spectroscopy, elemental analyses, inherent viscosity (ηinh), solubility and specific rotation measurements. All of the resulting polymers show optical rotation and are optically active. Thermal properties of the poly(amide-imide)s were investigated by using thermal gravimetric analysis(TGA). 相似文献
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Abstract The novel shish-kebab-type liquid crystalline poly(p-phenylene)s were synthesized through Suzuki coupling reaction from 2,5-bis[(4-n-alkoxyl)benzoyloxy]1,4-dibromobenzene (monomer 1) and 1,4-benzenediboronic acid bistrimethylene cyclic ester (monomer 2). Their structure and properties were characterized by GPC, DSC, X-ray diffraction and polarizing optical microscope (POM). It was found that the polymers turned to liquid crystalline phase above their melting point. The melting point (Tm) of the polymers decreases when the length of the alkoxy tails of the mesogenic units increases. The mesophase was identified by X-ray diffraction method. The polymers could dissolve in common organic solvents and show strong blue fluorescence. The maximum absorption bands of polymers prepared from annealed films have large red-shift due to the spontaneous orientation of the liquid crystalline side chains. The same phenomena were also observed in the fluorescence spectra. 相似文献
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A series of new nickel(Ⅱ)complexes with 2-aminomethylpyridine ligands,(2-PyCH_2NHAr)_2NiBr_2(Ar=2,6- dimethylphenyl 2a;2,6-diisopropylphenyl 2b,2,6-difluorophenyl 2c),have been synthesized and used as catalyst precursors for ethylene polymerization in the presence of methylaluminoxane(MAO).The catalysts containing ortho-alkyl-substituents afford high molecular weight branched polyethylenes as well as a certain amount of oligomers.Enhancing the steric bulk of the alkyl substituent of the catalyst resulted... 相似文献
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《中国化学快报》1995,(7)
STUDYONSYNTHESIS,CHARACTERIZATIONANDCATALYSISOFPILLAREDANIONCLAY(Ⅲ)──SYNTHESISOFZnAl-BW_(11)O_(39)Z(H_2)~(n-)ThanksforthesupportofFoundationofCECandtheopenlabofHydrothermalSynthesisinJinnUniversityeddifferentkindsoftriheteropolyoxometalate(TH'POMs)totheZnAIlayeredclays,usingtheesterificationofn-butylalcoholandaceticacidasprobereaction.andfoundthatthepillaredcompoundsweremoreactiveandselectivethanthesolidacidcatalystssuchasacidicion-exchangeresinsl4].Onthebasisofpreviouswork.wenowencapsulatetriheteropolyoxome 相似文献
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SYNTHESIS AND CRYSTAL STRUCTURE OF AZACROWN(2,2)DINITRATE[C12H 总被引:1,自引:0,他引:1
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<正> Cu8C24H60O12P6S13,Mt= 1651. 73,trigonal,R3,a=b = c= 12. 667(4) A,α= β=γ=111. 42(1)°.V=1441(2)A3,Z=1,Dc=1. 903g·cm-3,λ(MoKa) = 0. 71073 A ,μ(MoKa) = 35. 671cm-1, F ( 000 ) = 830, 293K. Final R = 0. 066,Rw= 0. 077 for 850 unique intensity data (I≥3σ(I)). Each unit cell of the crystal comprises of a neutral molecule of formula Cu8S(dtp)6[dtp=S2P(OEt)2],wherein the eight copper atoms are arranged at the corners of regular cube,with each dtp ligand μ4-bridged to each face of the cube and a μ8-S in the center bonded to all the eight copper atoms. Each copper atom is coordinated by four sulfur atoms in a tetrahedral configuration. The bond lengths of Cu-(μ8-S) are in the range of 2. 627(2)-2. 543(2) A ,those of Cu-S(dtp)in the range of 2. 251-2. 280A.The adjacent Cu-Cu bond lengths (2. 950(5)-3. 070(2) A) show a weak interaction between the copper atoms 相似文献