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1.
A reliable method to decide whether two polymers A and B are miscible or incompatible would be very helpful in many ways. In this contribution we demonstrate why traditional procedures cannot work. We propose to use the intrinsic viscosities [η] of the polymer blends instead of the composition dependence of the viscosities as a criterion for polymer miscibility. Two macromolecules A and B are miscible because of sufficiently favorable interactions between the two types of polymer segments. For solutions of these polymers in a joint solvent, this Gibbs energetic preference of dissimilar intersegmental contacts should prevail upon dilution and lead to the formation of interpolymer complexes, manifesting themselves in deviations from the additivity of intrinsic viscosities.  相似文献   

2.
两种大分子可以利用氢键或者库仑力形成高分子复合物,根据不同的作用力性质可分为氢键复合物(氢键作用)和聚电解质复合物(静电力)。这种通过物理共混得到的高分子复合物,表现出了与单组分高分子截然不同的性质和特点。这一特性决定了此类复合物在诸多领域的应用,目前应用较多的领域有生物医药、渗透汽化、增稠等。本文主要介绍了高分子复合物近年来研究和应用的进展情况。  相似文献   

3.
酚氧树脂/聚(4-乙烯基吡啶)高分子复合物的制备及表征   总被引:1,自引:1,他引:1  
采用元素分析、DSC、FTIR、紫外光谱及XPS等手段对酚氧树脂和聚(4-乙烯基吡啶)在氯仿中溶液共混形成的高分子复合物的组成及结构进行了研究,并与相应的共混物作了比较。结果表明,所得的各复合物的组成相同,其值与组分分子中的链节等摩尔比一致;而共混物也为相容体系,其组成与两高分子组分的投料比对应。基于实验结果,揭示了复合物的形成过程。  相似文献   

4.
闫佳文  马振毛 《应用化学》2014,31(7):823-827
采用超声法制备齐墩果酸(OA)与烷醇胺(EAs)[单乙醇胺(MEA)、二乙醇胺(DEA)或三乙醇胺(TEA)]复合物,利用差示扫描量热、X射线衍射、红外光谱和拉曼光谱等技术手段对复合物进行了表征。 发现OA与EA之间无新的化学键形成,它们以分子间力结合形成复合物。 OA与EA复合物提高了OA的溶解度,为OA新型给药系统提供新思路和理论依据。  相似文献   

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In order to improve the aqueous solubility and enhance the bioavailability of Hyperoside (Hyp), three inclusion complexes (ICs) of Hyp with 2-hydroxypropyl-β-cyclodextrin (2H-β-CD), β-cyclodextrin (β-CD), and methyl-β-cyclodextrin (M-β-CD) were prepared using the ultrasonic method. The characterization of the inclusion complexes (ICs) was achieved using Fourier-transform infrared spectroscopy (FTIR), scanning electronic microscopy (SEM), X-ray powder diffraction (XRPD), thin-layer chromatography (TLC), and 1H nuclear magnetic resonance (1H NMR). The effects of the ICs on the solubility and antioxidant activity of Hyp were investigated. A Job’s plot revealed that the Hyp formed ICs with three kinds of cyclodextrin (CD), all at a 1:1 stoichiometric ratio. The FTIR, SEM, XRPD, TLC, and 1H NMR results confirmed the formation of inclusion complexes. The water solubility of the IC of Hyp with 2-hydroxypropyl-β-cyclodextrin was enhanced 9-fold compared to the solubility of the original Hyp. The antioxidant activity tests showed that the inclusion complexes had higher antioxidant activities compared to free Hyp in vitro and the H2O2–RAW264.7 cell model. Therefore, encapsulation with CDs can not only improve Hyp’s water solubility but can also enhance its biological activity, which provides useful information for the potential application of complexation with Hyp in a clinical context.  相似文献   

7.
The polymer-bound Schiff base ternary manganese complexes [PS-SalPhe-Mn-L (L = Phen, Bipy and 8HQ)] have been prepared from the polymer-bound Schiff base ligand, a manganese salt and the second ligand, such as 1,10-phenanthroline (phen), 2,2‘-bipyridyl (bipy) and 8-quinolinol (8HQ). The polymer-bound Schiff base ternary manganese complexes were characterized by means of infrared spectrometry and ICPAES. The catalytic activities of the complexes have been studied in the aerobic epoxidation of long-chain linear aliphatic olefins. It is shown that 1-octene or 1-decene can be directly oxidized by molecular oxygen when catalyzed by PS-SalPhe-Mn-L(L=Phen, Bipy and 8HQ), and 1,2-epoxy alkane can be afforded in these reactions.  相似文献   

8.
A series of polymeric complexes were prepared from Fe~(2 ),Co~(2 ) or Ni~(2 ) and poly(Schiff base)(DAPcIPA), which was obtained by polycondensation of 5,6-diamino-1,10-phenanthroline(DAP)with isophthalaldehyde(IPA).The structures of the polymer and the polymeric complexes were characterized by IR,~1H-NMR and elemental analysis.The magnetic behavior of these complexes was measured as a function of magnetic field strength(0-3.98×10~6 A/m)at 5 K and as a function of temperature(5-300 K)at a magnetic field strength of 2.39×10~6 A/m.Experimental results show that DAPcIPA-Ni~(2 ),DAPcIPA-Co~(2 ) are soft ferromagnets while DAPcIPA-Fe~(2 ) exhibits features of an antiferromagnet.  相似文献   

9.
何茵  王雷  陈治  唐小真 《应用化学》1999,16(6):89-0
低分子量聚醚;聚氨酯固体电解质;离子电导率;硬段聚醚掺杂聚氨酯的合成及其离子导电性能  相似文献   

10.
稀土与5-苯基吡唑啉二硫代甲酸固态配合物的合成与表征   总被引:3,自引:1,他引:3  
在干燥氮气氛中 ,以 5 苯基吡唑啉二硫代甲酸钠和无水稀土氯化物为原料 ,乙腈为溶剂 ,制备出稀土与 5 苯基吡唑啉二硫代甲酸形成的 9个新型固态配合物 ,产率达 40 %以上。经元素分析、红外光谱、差热 热重分析和电导测定 ,确定其组成为 :Na[RE(S2 CNC9H9N) 4·xH2 O](RE =La~Dy ,Y ,除Ce和Pm外 ) ,配体是通过两个硫原子以双齿形式与稀土离子配位。热分析表明 ,配合物开始分解温度均低于配体的分解温度 ,说明配合物的热稳定性不如配体。配合物的乙腈溶液 (浓度为 1 2 4~ 1 32× 10 - 3mol·dm- 3)的摩尔电导值在 86~ 10 4Ω- 1 ·cm- 2 ·mol- 1 范围 ,配合物为 1∶1型电解质  相似文献   

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罗贤  吕桂琴 《无机化学学报》2011,27(9):1705-1708
运用自组装和电化学组装联用方法,将镍卟啉配合物THPPNi和Keggin型硅钨酸SiW12修饰到玻碳电极上,制备镍卟啉修饰电极和镍卟啉/硅钨酸复合修饰电极,研究其在DMF溶液中的电化学行为,测定在碱性条件下对NO2-和BrO3-的电催化性能。循环伏安和交流阻抗研究结果表明,复合修饰电极THPPNi/SiW12的电极过程属于扩散控制过程;复合修饰电极优于单一修饰金属卟啉和多酸修饰电极。  相似文献   

13.
Literature data as well as our own experimental results devoted to the complexation of polycarboxylic acids with various water‐soluble polysaccharides (methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, starch, and dextran) by means of hydrogen bonding are systematized and analyzed. The specific peculiarities of interpolymer complexes based on polysaccharides‐polycarboxylic acids are demonstrated. The perspectives for the application of these interpolymer complexes are considered. It was shown that these materials possess good biocompatibility and adhesive properties. The promising directions for further study of interpolymer complexes between polycarboxylic acids and nonionic polysaccharides as well as existing gaps in the knowledge in this field are pointed out.

Formation of compact IPCs and hydrophilic interpolymer associates.  相似文献   


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Inclusion compounds of transition metal complexes of cycloocta-1,5-diene (cod) and norbornadiene (nbd) with cyclodextrins were prepared. Two-to-one (cyclodextrin:guest) inclusion compounds were obtained in high yields by the treatment of β-cyclodextrin (β-CD) with [(L)RhCl]2 (L = nbd or cod) and 1:1 inclusion compounds were obtained by the reaction of β-CD with (cod)PtX2 (X = Cl, Br, or I) in high yields, while γ-CD formed 1:1 inclusion compounds with (cod)PtX2 (X = Br or I). The formation of inclusion compounds is selective. α-CD did not form inclusion compounds with any transition-metal complexes with cycloocta-1,5-diene. Thermogravimetric measurements show that the complexes are stabilized by inclusion in cyclodextrin cavities. The inclusion compounds were characterized by 1 H-NMR, IR, UV, and circular dichroism spectra.  相似文献   

16.
The oxidative addition of XRCN to PtL4 yields cis-and/or trans-PtX(RCN)L2 (X = Cl, Br; R = (CH2)n, n = 1, 2, 3; L = PPh3, PPh2CH3, AsPh3). L is readily displaced by more basic phosphines or by a diphosphine. In each case the trans complex is the thermodynamically more stable isomer and cis-trans isomerization catalyzed by free L occurs in dichloromethane. Insertion of CO in the σ Pt? C bond takes place quantitatively in the case of cyanoethyl and cyanopropyl. Abstraction of X by AgBF4 gives cis or trans cationic complexes with N-bonded CN group.  相似文献   

17.
Interactions between poly(vinylpyrrolidone) (PVP) and p-hydroxyben-zoic acid-formaldehyde copolymer have been studied in methanol solution. The component polymers appear to form interpolymer complexes in distinct stages. The results are interpreted in terms of 1) hydrogen bonding, 2) ion-dipole interaction, 3) tacticity of PVP, and 4) multiple coordinating positions of component polymers.  相似文献   

18.
The conformational behavior of a single AB block copolymer is studied by Monte Carlo simulation. The A‐A and A‐B interactions have the character of excluded volume interactions while the B units attract each other; the attractive B blocks can move along the chain. The collapse transition of the chain with increasing attraction between the B units is analyzed. Intrachain separation of the A and B units takes place in the course of the chain collapse with the formation of “globule with a tail” conformations. The globule is formed by the attractive moving B blocks while the tail consists of the swollen A segments. The model of AB block copolymer with moving B blocks can describe the behavior of interpolymer complexes between a long macromolecule and shorter polymer chains.

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