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1.
一种疏水缔合水溶性聚合物的合成及其溶液性能   总被引:1,自引:1,他引:0  
粘度;抗盐性;表面活性剂;一种疏水缔合水溶性聚合物的合成及其溶液性能  相似文献   

2.
Composite gels based on polyacrylamide and poly(N-isopropyl acrylamide) with incorporated sodium bentonite particles are synthesized. It is shown that the presence of hydrophobic isopropyl groups in a polymer molecule promotes the subsequent formation of highly ordered aggregates of clay and cetylpyridinium chloride in a gel composite. An increase in temperature results in the collapse of composite gels based on poly(N-isopropyl acrylamide); however, no marked changes in the structure of lamellar aggregates of clay and surfactant are observed. It is revealed that the gel can stabilize lamellar structures formed in organoclay suspension prior to the incorporation into swollen polymer network.  相似文献   

3.
The polymer electrolytes based on chitosan and ammonium chloride were prepared by solution casting technique and the properties were studied. The addition of ammonium chloride results in: (1) the enhancement of the amorphous nature of the polymer electrolytes; (2) the shift of the absorption bands of amino group at 1566 cm?1 and the carbonyl group at 1640 cm?1 towards lower wave number, and the appearance of a new absorption band at 1759 cm?1; (3) a decrease of the glass transition temperature. The 20 wt % ammonium chloride doped polymer electrolyte has the best room temperature electric property, the lowest activation energy and the highest ionic conductivity. Placing the as‐prepared polymer electrolyte in a dryer is adverse for the sample's moisture content, and results in higher activation energy and lower ionic conductivity. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 260–266, 2010  相似文献   

4.
The preparation of polyester (PQ) and copolyester (PQ-DIOL) catalysts having quaternary ammonium groups was performed, and an aromatic polyester (PEA) was directly synthesized from isophthaloyl chloride and diphenolic acid by aqueous/organic interfacial polycondensation using these polymer catalysts. The yield and molecular weight of the polyester were affected by the structure of the pendant quaternary ammonium groups.  相似文献   

5.
邹剑华  林德  施文芳 《化学学报》2002,60(5):926-930
以1,1,1-三羟甲基丙烷为核,4-N,N-(2-羟乙基)-4-酮丁酸为单体,按照 一定比例,合成理论上第二代羟端基超支化聚酰胺酯,再与丙烯酰氯反应获得丙烯 酸化超支化聚酰胺酯预聚物(HAPAE-2-A),它在光引发剂存在下经紫外光辐照可 以快速固化成膜。根据~1H NMR 谱测定所得产物的反应程度为85%。采用凝胶渗透 色谱和气相渗透法测定所得产物的分子量分布和数均分子量分别为2.16和1620 g/mol,与其理论分子量相比,其反应程度为89%,从而估算产物实际端基丙烯酸 酯双键数为10左右。采用光-差热分析仪研究HAPAE-2-A的反应动力学,发现当体系 中加入多官能团单体,如三羟甲基丙烷三丙烯酸酯、己二醇二丙烯酸酯和乙氧基一 缩二乙二醇丙烯酸酯时,多官能团单体的官能度及含量会对体系的最大光聚合反应 速率和不饱和双键的反应程度产生较大的影响。通过动态力学热性能测试发现 HAPAE-2-A光固化膜的玻璃态转化温度随多官能团单体的加入而提高。  相似文献   

6.
An enatioselective surface-imprinted polymer for an amino acid derivative (N-benzyloxycarbonyl-glutamic acid, Z-Glu) was prepared using the bifunctional molecule, benzyldimethyl-n-tetradecylammonium chloride (Zeph). The long-chain quaternary ammonium chloride was found to serve the dual function of an emulsifier and host molecule, while conventional functional molecules possess only the latter function. Chiral recognition ability and ligand specificity of the imprinted polymer were demonstrated by several batchwise tests using different four amino acid derivatives. The surface-imprinted polymer could recognize the chirality of N-protected glutamic acid; therefore, it preferentially adsorbed the corresponding enantiomer that was imprinted in the preparation. The pH and buffer concentration in the aqueous solution are the key factors enhancing enantioselectivity. The molecularly imprinted polymer could distinguish the specific structure from other molecular analogues, even though the structural difference was the only methylene group. The high interfacial activity of the functional molecule and the low swelling property of the imprinted polymer were important in ensuring high imprinting effect. The mechanism of chiral recognition on the polymer was also discussed.  相似文献   

7.
本文合成了一些季铵盐聚合物试剂,研究了这些试剂对三氯乙酸分解生成三氯乙酰氯的催化作用。不同季铵盐聚合物催化剂对三氯乙酸分解的催化活性顺序如下: (?) (?) 聚合物催化剂经重复使用后,活性并无明显降低。  相似文献   

8.
硫酸铵水溶液中丙烯酰胺与正离子单体的分散共聚研究   总被引:4,自引:0,他引:4  
以硫酸铵(AS)水溶液为介质,进行丙烯酰胺(AM)与正离子单体甲基丙烯酰氧乙基三甲基氯化铵(DMC)分散共聚合,制备出水溶性聚合物分散体.研究了盐浓度、分散稳定剂浓度及其分子量、单体浓度等对反应体系及分散体粒径的影响.结果表明,随着分散稳定剂的用量从6%增加到14%,分散体的平均粒径先下降,后又随之上升.分散稳定剂分子量越大,所得分散体的平均粒径越小.硫酸铵和单体的浓度对平均粒径和粒子形态等影响显著,只有在较小的范围内才能制备出粒径较均一的正离子型水溶性聚合物分散体;硫酸铵浓度越大,生成聚合物分子量越低.  相似文献   

9.
In last few decades, polymer electrolyte is the most promising candidate for the fabrication of electrochemical devices. In current work, the influence of adding the room-temperature ionic liquid (trifluoromethanesulfonic chloride – CClF3O2S) in polyethylene oxide (PEO): ammonium iodide (NH4I) polymer electrolyte has been studied. The IL-doped polymer electrolyte films are synthesized by solution casting method with varying stoichiometric ratios. Several experimental techniques including optical polarizing microscope, impedance spectroscopy, X-ray diffraction, Linear sweep voltammetry, Ionic transference number thermal analysis, and electrical conductivity measurements at room temperature have been studied in detail. The complex material's maximum conductivity has been determined to be 3.3 × 10−5 S cm−1 at room temperature. The POM images show the increase in amorphous region which further confirm the improvement in ionic conductivity. Ionic transference number 0.96 shows the system is purely ionic in nature. The ESW of the IL doped polymer electrolyte is also sawed to be 3.32 V which is suitable for the fabrication of electrochemical devices.  相似文献   

10.
Dispersion copolymerization of acrylamide (AM) with 2-methylacryloylxyethyl trimethyl ammonium chloride (DMC) has been carried out in aqueous salts solution containing ammonium sulfate and sodium chloride with poly(acryloylxyethyl trimethyl ammonium chloride) (PDAC) as the stabilizer and 2,2′-azobis[2-(2-inidazolin-2-yl)propane]-dihydro chloride (VA-044) as the initiator. A new particle formation mechanism of the dispersion polymerization for the present system has been proposed. The effects of inorganic salts and stabilizer concentration on dispersion polymerization have been investigated. The results show that varying the salt concentration could affect the morphology and molecular weight of the resultant copolymer particles significantly. With increasing the stabilizer concentration, the particle size decreased at first and then increased, meanwhile the effect on the copolymer molecular weight was the contrary. These results had been rationalized based on the proposed mechanism.  相似文献   

11.
Carbon nanotube based nanocomposite membranes have been fabricated through solution casting by embedding multi-walled carbon nanotubes (MWCNTs) within polyetherimide (PEI) polymer host matrix. In order to achieve fine dispersion of nanotubes and facilitate strong interfacial adhesion with the polymer matrix, the nanotubes were first treated with surfactants of different charges, namely anionic sodium dodecyl chloride, cationic cetyl trimethyl ammonium chloride and non-ionic Triton X100, prior to the dispersion in the PEI dope solution. Dispersion of MWCNTs in N-methyl-2-pyrrolidone solvent showed that the agglomeration and entanglement of the nanotubes were greatly reduced upon the addition of Triton X100. Scanning electron microscopy and atomic force microscopy examination has evidenced the compatibility of Triton X100 dispersed MWCNTs with the polymer matrix in which a promising dispersion and adhesion has been observed at the MWCNT-PEI interface. The increase in both thermal stability and mechanical strength of the resulting Triton X100 dispersed MWCNT/PEI nanocomposite indicated the improved interaction between MWCNTs and PEI. This study demonstrated the role of Triton X100 in facilitating the synergetic effects of MWCNTs and PEI where the resulting composite membrane is anticipated to have potential application in membrane based gas separation.  相似文献   

12.
Polymer colloids with internal ordering were synthesized using hydrolytic condensation of octadecyl-dimethyl(3-trimethoxysilylpropyl)ammonium chloride (ODMACl) and a mixture of ODMACl and the trisodium salt of the triacetic acid N-(trimethoxysilylpropyl)ethylenediamine (TANED). The structure and morphology of these colloids were studied with small-angle X-ray scattering, transmission electron microscopy, nuclear magnetic resonance, sedimentation in ultracentrifuge; and other methods. When polymer colloids are obtained from a single precursor (ODMACl), their local structure, molecular weight characteristics, and morphology strongly depend on the reaction conditions, while lamellar ordering remains nearly unaffected. Use of a mixture of cationic and anionic silanes (ODMACl and TANED) as precursors in hydrolytic condensation results in novel zwitterionic copolymer colloids with two-dimensional hexagonal packing. Interaction of the ODMACl quaternary ammonium groups with the three carboxy groups of TANED leads to replacement of sodium and chloride ions and formation of gegenions, resulting in a molar ratio ODMACl:TANED = 3:1 (each TANED molecule contains three carboxy groups). Due to their ordered interior, polyODMACl (PODMACl) and PODMACl-TANED colloids can be used as templates for controlled positioning of nanoparticles within these colloids. For example, lamellar ordering controls Pt nanoparticle formation within PODMACl colloids providing Pt nanoparticle alignment within the lamellar structure. Loading of PODMACl-TANED colloids with iron salts followed by pH increase results in the formation of iron oxide nanoparticles located within PODMACl-TANED cylinders.  相似文献   

13.
Modified polysaccharide was synthesized by the reaction of amylopectin with a cationic monomer, (1,2-epoxyprop-3-yl)triethylammonium chloride, in alkaline solution in the presence of Fenton’s reagent. The influence of the concentrations of amylopectin, gelatin, their polymer-inorganic hybrids, and modified pectin on their flocculating properties in free (unrestricted) sedimentation of ocher suspension as a model disperse system was studied. Amylopectin exerts a stabilizing effect, whereas the modified pectin and polymer-inorganic hybrid exert a flocculating effect. The influence of the mode of introducing polymer additives on the flocculating effect and aggregation of ocher particles was analyzed.  相似文献   

14.
A novel multifunctional conjugated polymer (RCP‐1) composed of an electron‐donating backbone (carbazole) and an electron‐accepting side chain (cyanoacetic acid) connected through conjugated vinylene and terthiophene has been synthesized and tested as a photosensitizer in two major molecule‐based solar cells, namely dye sensitized solar cells (DSSCs) and organic photovoltaic cells (OPVs). Promising initial results on overall power conversion efficiencies of 4.11% and 1.04% are obtained from the basic structure of DSSCs and OPVs based on RCP‐1, respectively. The well‐defined donor (D)‐acceptor (A) structure of RCP‐1 has made it possible, for the first time, to reach over 4% of power conversion efficiency in DSSCs with an organic polymer sensitizer and good operation stability.  相似文献   

15.
通过氧化还原引发荆引发的接枝共聚反应,使阴离子型单体丙烯酸(AA)和阳离子型单体三甲基烯丙基氯化铵(TMAAC)在羧甲基壳聚糖(CMCTS)的分子链上接枝共聚,制得羧甲基壳聚糖接枝-(聚丙烯酸-co-聚三甲基烯丙基氯化铵)(CMCTS-g-(PAA-co-PTMAAC)两性聚电解质高吸水性树脂.采用红外光谱对产物的结构进行了表征,比较了反应条件对产物吸液性能的影响.发现制备具有良好吸液性能的高吸水性树脂的最优化反应条件为:TMAAC占单体总质量的14.3%,mNNMBA/mAA值在0.014附近,单体总质量为CMCTS质量的9.33倍,丙烯酸中和度在20%~30%之间.研究发现,随外部溶液pH值的变化,两性聚电解质高吸水性树脂的溶胀性能在酸性和碱性条件下各有一个最大值,在等电点处产物的吸液性相对较低.  相似文献   

16.
聚二烯丙基甲基苄基氯化铵的合成及粘度行为   总被引:1,自引:1,他引:0  
刘立华  李鑫  曹菁  令玉林 《应用化学》2011,28(7):777-784
以甲胺、烯丙基氯、NaOH、氯化苄和偶氮二异丙基咪唑啉盐酸盐为原料,合成了聚二烯丙基甲基苄基氯化铵(PDAMABC),采用FT IR、1H NMR和元素分析对其结构进行表征,并考察了其在氯化钠、氯化钾、溴化钾、氯化钙、氯化镁、硫酸镁和硫酸钠溶液中的粘度行为。 将所得水相和低沸点馏分回用,二烯丙基甲基胺的收率从72.79%提高至83.41%;以水与乙醇为混合溶剂(V(H2O)∶V(C2H5OH)为1∶3~2∶3),合成的二烯丙基甲基苄基氯化铵收率较高且水溶性好。 PDAMABC的比浓粘度随外加盐浓度增加而降低。 在0.1 mol/L NaCl溶液中,当其质量浓度低于0.031 25 g/L时,表现为聚电解质行为;质量浓度大于0.125 g/L时,表现为中性聚合物的粘度行为。 外加盐对比浓粘度的影响顺序为:Na2SO4<NaCl<KCl<MgSO4<MgCl2<CaCl2<KBr。 阴离子的屏蔽作用是导致比浓粘度降低的主要原因。  相似文献   

17.
Journal of Solid State Electrochemistry - Solid polymer electrolyte based on iota-carrageenan (i-carrageeenan) with ammonium thiocyanate (NH4SCN) has been prepared by solution casting technique...  相似文献   

18.
The binary radical copolymerization of acrylic acid amides (acrylamide and N-cyclohexen-1-ylacrylamide) with alkenyl halides (vinyl chloride, vinyl bromide, and allyl chloride) has been studied. The constants of relative activity of the monomers used are calculated. For the systems under investigation, the occurrence of dehydrochlorination of a polymer chain and protonation of a carbonyl group occur is confirmed. Allyl chloride shows the most pronounced tendency toward dehydrochlorination, while in the case of vinyl chloride, this tendency is the least distinct. The polymer-analogous transformations result in copolymers containing polyene fragments and units of ammonium or oxonium amide salts.  相似文献   

19.
"Quat-primer" polymers bearing cationic groups were investigated as a surface modifier for Tb-doped cerium phosphate green-emitting fluorescent nanorods (NRs). The NRs were synthesized by a microwave process without using any complex agents or ligands and were characterized with different analytical tools such as X-ray diffraction, transmission electron microscopy, and fluorescence spectroscopy. Poly(ethyleneimine) partially quarternized with glycidyltrimethylammonium chloride was synthesized separately and characterized in detail. (1)H and (13)C NMR spectroscopic studies revealed that the quaternary ammonium group was covalently attached to the polymer. UV-vis spectroscopy was used to examine the stability of the colloidal dispersions of the bare NRs as well as the modified NRs. ζ potential, thermogravimetric analysis, and atomic force microscopy studies were carried out to confirm that the positively charged Quat-primer polymer is adsorbed on the negatively charged surface of the NRs, which results in high dispersion stability. Emission spectra of the modified NRs indicated that there was no interference of the Quat-primer polymer with the fluorescence behavior.  相似文献   

20.
Surfactant-free gelatin/heptamolybdate (HM) hybrid nanoparticles are prepared by a simple and environmentally friendly approach utilizing the electrostatic interaction between anionic HM and the zwitterionic gelatin. The obtained nanoparticles have a tunable size and very high HM loading content up to about 70%. In vitro and in vivo experiments prove that the gelatin/HM hybrid nanoparticles exhibit significantly better antitumor activity than plain ammonium heptamolybdate solution. Therefore, the gelatin/HM hybrid nanoparticles reported here may serve as a prototype platform for polymer/polyoxometalate (POM) hybrid nanoparticles as cancer treatment agents and hence open up more opportunities to maximize the potential of POM-based pharmaceutical agents.  相似文献   

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