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1.
A series of novel mesogenic polyamides containing a flexible pendent side group wassynthesized by solution condensation polymerization. The new monomers, diacids and di-amines containing flexible elements of diferent lengths, were also synthesized and character-ized by ~1HNMR, mass spectroscopy and elemental analysis. The polymers were character-ized by viscosity measurements, differential scanning calorimetry (DSC), X-ray diffiactionand polarizing optical microscopy These studies revealed that polyamides containingflexible elements of a sufficient length exhibited thermotropic liquid crystalline(LC) pro-perties. The melting temperatures of this series of polymers were particularly sensitive tothe length of the flexible segment on the main chain and that of the flexible pendent esterside chain. Lyotropic LC behaviours were also observed in solution.  相似文献   

2.
Two new polyphenylquinoxaline-platinum and rhodium complexes were synthesized and iden-tified by X-ray photoelectron spectroscopy. Their catalytic properties on hydrosilylation and hy-drogenation of olefines have been investigated. It was found that these polymer complexes possessedhigh selective catalytic activities, and were easily recoverable after each reaction and could berepeatedly used for more than 10 times while maintaining the same effectiveness.  相似文献   

3.
Four γ-substituted-propylcyclotetrasiloxanes have been synthesized. Emulsion copolymerizations of these cyclosiloxanes with octamethylcyclotetrasiloxane have been carried out both in cationic and anionic emulsion systems. By way of these reactions, stable emulsions of organosilicon polymers which contain carbonfuctional groups such as γ-hydroxypropyl, γ-acetoxypropyl and γ-chloropropyi have been obtained.The effects of temperature, catalyst and the amount of γ-substituted-propylcyclotetrasiloxanes in emulsion copolymerizations have been studied.  相似文献   

4.
1-[(2-hydroxyethoxy)methyl]benzotriazole and -indole containing perfluoroalkyl group have been synthesized.  相似文献   

5.
Abstract

As part of a continuing studies of α-phosphoryl sulphoxides, racemic dimethylphosphorylmethyl p-tolyl sulphoxide (1) was prepared and resolved into optical isomers. Sulphoxide (+)-1 with the R chirality at sulphur was synthesized stereospecifically by treatment of (?)-menthyl p-tolylsulphinate with dimethylphosphorylmethyllithium. This communication describes some transformations of optically active 1.  相似文献   

6.
SYNTHESIS OF STEREO-ISOMERS OF SECOCLAUSENAMIDE Ⅰ AND SECODEMETHYLCLAUSENAMIDE ⅡSYNTHESISOFSTEREO-ISOMERSOFSECOCLAUSENAMIDEⅠA...  相似文献   

7.
Two kinds of fishbone-like, β-diketone-based liquid crystalline polysilsesquioxanes(FBDKLCP'S), homopolymeric (H-FBDKLCP) and copolymeric (C-FBDKaLCP) have been first synthesized via the hydrosilylation reaction of a vinyl-terminated β-diketone with the homopolymeric ladderlike polyhydrosilsesquioxane (LPHSQ) and random copolymethylhydrosilsesquioxane (LRPMHSQ) respectively. These new kinds of FBDKLCP with M of 10~4 is thermotroic liquid crystalline polymer and its clearing temperatures T_i's and mesophase range △T's are much higher than those of the corresponding comb-like β-diketone liquid crystalline polysiloxane (DKLCP) by about 200℃. Similar results have been observed with the comparison of the two different structure Cu-coordinating compounds The significant increases in T_((?))'s and △T's of the FBDKLCP and Cu-FBDKLCP are mainly attributed to the great rigidity of the ladderlike polysilsesquioxane backbone.  相似文献   

8.
In this paper the miscibility of poly (ε-caprolactone) (PCL) and aliphatic polycarbonate (APC) is studied by using DSC. The results show that PCL and APC are miscible in all ranges of composition. The interaction parameter between the polymers is calculated from the melting point depression data. Using optical microscope, the shapes of the PCL spherulites in the blends are observed.  相似文献   

9.
10.
Six polyamides with pendant 5-fluorouracil group were synthesized by the polycondensation ofdi-p-nitrophenyl N-(5-fluorouracil-1-acetyl)glutamate with a series of polymethylene diamines.All of the new polyamides obtained are soluble in water. Their chemical structures were confirmedby ~1H NMR, UV and IR spectra as well as elemental analyses. The antitumor activity of some ofthese polyamides were tested against Ehrlich Ascites Carcinoma in mice, III_a showed an inhibitionrate of 43%.  相似文献   

11.
Acrylonitrile (AN)-chlorinated polyethylene (CPE)-styrene (St) (ACS) terpolymer was synthesized by suspension-swelling graft copolymerization method, in which two key factors such as dispersing system and time were studied. Highly effective comples dispersing system was chosen and determined, and two-layer protection model was put forward to clarify the stable effect mechanism Varying the swelling time of CPE in AN and St monomer mixture, some results such as grafting effect, particle characteristics, rubber particle morphology and its size distribution, and properties of ACS resins were investigated , thus the optimum swelling time was proposed.  相似文献   

12.
Different proportions of β-cydodextrin and epichlorohydrin were used to prepare a group of β-cyclodextrin polymers. The relationship between the reaction extent and the molar ratios of reactants was discussed according to the results of ~1H-NMR, ~(13) C-NMR spectra and elemental analysis. Especially, high resolution ~1H-NMR spectra were usd for studying the reaction active sites and the extent of reaction. The solubility of oil soluble drugs in water was largely improved in the presence of water-soluble β-cyclodextrin polymer.  相似文献   

13.
The total synthesis of isodeoxyarteannuin 3 was achieved starting from norsesquiterpenoid lactone 5 which was obtained from 10-R( )-citronellal 4. The synthetic route is Summarized in Fig. 1.  相似文献   

14.
Active esters, 8-acryloyloxyquinoline (AQ) and 8--methacryloyloxyquinoline (MAQ) were synthe-sized and characterized. It was found that polymers of these two monomers can react with nucleophilicreagents such as amines or alcohols under mildcondition. The ammonolysis yield of P(AQ) for aliphaticamines were above 60% and the specific activity of the immobilized glucoamylase on P(AQ) andP(MAQ) was 5328 u/g and 4320 u/g, respectively.  相似文献   

15.
The polymerization rates of three cyanopyridines catalyzed by cuprous chloride-zinc system are measured, and the structure of the formed polymer is also determined. Compared with aromatic nitrile, cyanopyridines polymerize faster and form polyconjugated polymer with skeleton—(C=N)—_n instead of triazine structure. This chain-polymer possesses semiconductive property, and can be converted into conductive material by thermal treatment. In addition, the polymerization kinetics of 3-cyanopyridine catalyzed by 3-cyanopyridinium perchlorate is investigated. It is found that the polymerization rate is directly proportional to the concentrations of monomer and catalyst, and the activation energy of the polymerization is 103.1 KJ/mol.  相似文献   

16.
In a capacitively coupled discharge with external electrodes, He, H_2, N_2 or Ar were used as plasmagas, polymerization of octafluorocyclobutane was carried out under different conditions by varyingdischarge power, pressure, plasma gas and plasma-gas/monomer ratio. Structure of polymerizedproducts was characterized by IR spectroscopy and ESCA measurement. It was found that therewere six elements in the products, i.e. C, F, Si, O, N and H. The probably existed groups in poly-mers wer investigated. By analyzing the resolved peaks of C_(1S) region in ESCA spectra, effect of thereaction conditions on degree of branching of the polymerized products and the relationship of thepolymer structure wth the mechanism of the competitive ablation and polymerization process werestudied. In addition, polymer deposition process occurring in glow discharge was discussed.  相似文献   

17.
A new series of liquid crystal polyesters with T-shaped two-dimensional mesogenic units weresynthesized by melt polycondensation of the diacetates of 2-(4'-alkoxy -phenyl)-hydroquinones with 4,4'-alkylenedioxydibenzoic acid. The polymers were characterized by using polarized microscopy, DSC and X-ray diffraction. It was realized that all the polymers have nematic thermotropic liquid crystallinecharacteristics. The melting temperature (T_m) and isotropization temperature (T_i) of the polymers changeregularly with varying lengths of the alkoxy side group and the length of the alkylene group in the main chainin company with an even-odd effect. The mesophase temperature range also varies regularly with the polymerstructure. It is shown that the mesophase range has been widened.  相似文献   

18.
A series of liquid crystalline polymers with T-shaped two-dimensional mesogenic unitswere synthesized via low temperature solution polycondensation of 2-(4'-alkoxy-phenyl)hydroquinone with various diacyl dichlorides. The polymers were found to be nematic andshown thermotropic liquid crystalline behaviors through observations using DSC, polarizedmicroscopy and X-ray diffraction. The melting temperature T_m and the isotropizationtemperature T_i of the polymers change regularly with varying of the monomer structures.  相似文献   

19.
A precursor 12 of sinulariol-D,sinularial-A and sinularic acid-A(marinecembranoids)was prepared from geraniol through nine steps  相似文献   

20.
STUDIESONTHESYNTHESISANDDNA-BINDINGABILITYOFZINCFINGERMOTIF¥XiaoYuHU;RuiWANG;XiangQunLI(StateKeyLaboratoryofAppliedOrganicChe...  相似文献   

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