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1.
The chemical composition, morphology of the particles of positively charged layered double hydroxides (LDHs) were studied by ICP, Mastersizer, TEM. The preliminary results indicated that with adding LDHs to 1% laponite dispersion the yield stress of laponite/LDHs mixed dispersions increased at first, then decreased dramatically to a minimum, and the yield stress rose again when LDHs increased further.  相似文献   

2.
Russian Journal of Electrochemistry - The transport properties of solid composite electrolytes (1 – x)LiClO4–xCND (where СND are “UDA-S” nanodispersed diamonds with a...  相似文献   

3.
Russian Journal of Applied Chemistry - The effect of the residual catalyst for the synthesis of multi-walled carbon nanotubes (MWCNTs) on the electrophysical properties of MWCNT–polyethylene...  相似文献   

4.
The formation, and subsequent structural, thermal and adsorptive properties of single-component metal–organic framework crystal-glass composites (MOF-CGCs) are investigated. A series of novel materials exhibiting chemically identical glassy and crystalline phases within the same material were produced, where crystalline ZIF-62(Zn) was incorporated within an agZIF-62(Zn) matrix. X-ray diffraction showed that the crystalline phase was still present after heating to above the glass transition temperature of agZIF-62(Zn), and interfacial compatibility between the crystalline and glassy phases was investigated using a mixed-metal (ZIF-62(Co))0.5(agZIF-62(Zn))0.5 analogue. CO2 gas adsorption measurements showed that the CO2 uptakes of the MOF-CGCs were between those of the crystalline and glassy phases.  相似文献   

5.
Russian Journal of Electrochemistry - Copper(II) ferrite is synthesized by the co-precipitation method in the absence and in the presence of polyvinyl alcohol which is followed by thermally...  相似文献   

6.
The main objective of this article is to introduce a new natural fiber as a reinforcement in polymers for making composites for lightweight applications. The extraction of golden cane (Chrysalidocarpus lutescens) fiber and the mechanical properties of the fiber-reinforced polyester composites are described. The composites were formulated up to a maximum volume fraction of 0.43, resulting in a mean tensile strength and modulus of 2.13 and 2.26 times and mean flexural strength and modulus of 1.94 and 2.89 times greater than those of plain polyester, respectively, at a higher volume fraction of 0.43. The work of fracture in impact is measured to be 358 J/m. The results of this study indicate that golden cane fibers have potential as reinforcing fillers in plastics in order to produce inexpensive materials with high toughness.  相似文献   

7.
Lapekin  N. I.  Shestakov  A. A.  Brester  A. E.  Popov  M. V.  Bannov  A. G. 《Doklady Chemistry》2021,500(2):219-223
Doklady Chemistry - The electrical conductivity of carbon nanofiber–thermally expanded graphite compacted systems at various component mass ratios was investigated. Because the initial carbon...  相似文献   

8.
Polyaniline (PANI) nanocomposites were prepared with fly ash (FA) either by aging the starting materials (aniline and FA) before oxidative polymerisation or by including poly(styrene sulphonic acid) (PSSA) eliminating the aging step. The aging procedure formed polymer nanotubes that have cross-sectional diameters of 50–110 nm. The procedure involving PSSA produced nanorods and nanofibres composites that have diameters of 100–500 nm and length of up to 10 μm attributed to the presence of metal oxides and silica in FA. The electrochemical analysis of the PANI–PSSA–FA nanorod composites shows three redox couples with formal potentials, , values of 105 mV, 455 mV and 670 mV, and conductance, C, value of 1.21 × 10−2 S. The UV-Vis spectroscopy of the polymeric nanorod shows absorption maxima at 340 and 370 nm (due to π–π* transition of the benzoid rings), and 600–650 nm (due to charge transfer excitons of the quinoid structure), which are characteristic of emeraldine base.  相似文献   

9.
Organic photovoltaic devices have attracted a great attention because of their light weight and processability, and the ease of material design on the molecular level. There are a number of reports on organic photovoltaic devices using a variety of dyes1-…  相似文献   

10.
Mixed aniline–melamine–formaldehyde polymer was synthesized by parallel polycondensation of the monomers with formaldehyde. Copper(II) chloride and copper oxides (CuO, Cu2O) were introduced in situ the process. X-ray diffraction analysis revealed the presence of crystalline CuO phases at introducing CuCl2 into the polymer and the appearance of copper particles in all the synthesized composites after using them as catalysts in electrohydrogenation of o-nitroaniline, which is caused by electrochemical reduction of copper cations from copper oxides. The use of the synthesized composites for the cathode activation in electrohydrogenation of o-nitroaniline increases the process rate by a factor of 1.5–2.5 compared to electrochemical reduction, and with 100% conversion to o-phenylenediamine.  相似文献   

11.
Russian Journal of Applied Chemistry - The results of a study on the production of graphite–diamond nanocompositions by partial oxidation of a detonation synthesis blend in aqueous solutions...  相似文献   

12.
Crosslinked macroporous polyacrylamide (PAM) was prepared with inverse phase suspension polymerization technique.After treatment with hydrazine,the polymer was functionalized with chloroacetic acid,trifluoroacetic acid diethylenetriaminepentaacetic acid (DEPAA),and maleic acid,respectively,and PAM based adsorbents beating carboxyl functional groups for low density lipoprotein (LDL) apheresis use were obtained.The blood compatibility and the adsorption properties for plasma lipoproteins of PAM based adsorbents were investigated.  相似文献   

13.
The electrochemical behavior of platinized Ebonex® was studied. The electrochemical and semiconductor properties of electrodes can be varied within wide limits by thermal treatment of Ebonex®/Pt, which selectively affects the electrocatalytic activity of anodes in the oxygen evolution reaction. The reduction peak of platinum oxides on the cyclic voltammetry (CV) curves can be used as a correlation parameter when evaluating the electrocatalytic activity of Ebonex®/Pt electrodes in the oxygen evolution reaction.  相似文献   

14.
Synthesized sodium N-pamitoyl amino acids were evaluated for surface and antimicrobial properties and compared with sodium lauryl sulfate (SLS). Emulsion stability of the amino acid surfactants and calcium tolerance of the sodium N-palmitoyl isoleucine were better as compared to SLS. Wetting ability and foaming properties of the palmitic acid-based surfactants were inferior to SLS. N-Acyl amino acids exhibited better antibacterial activity compared to sodium salts of N-acyl amino acids and standard compounds against Staphylococcus aureus MLS-16 and Bacillus subtilis. These studies revealed that the palmitoyl amino acid surfactants can be exploited in household, skin care formulations, and industrial applications.  相似文献   

15.
Depolymerization for different time intervals of high molecular weight chitosan using 2 mol⋅L−3 HCl resulted in low molecular weight (LMW) chitosan of 6, 10, 13, 18, and 30 kDa. These were studied using the FT-IR which indicated that the depolymerization process did not influence the chemical structure. LMW chitosan increases the surface tension of water but adjusting the ionic strength (1% NaCl) caused LMW chitosan to reduce the water surface tension. The zeta potential increased with increasing concentration up to a maximum in 1% NaCl solutions. Particle size showed a reduction in size with increasing concentration. This behavior in reduction of particle size was similar to that for the stiffness parameters. These physico-chemical properties showed that LMW chitosan was present in low concentration in its extended form while in higher concentrations it adopted a more contracted form. This change in conformation was confirmed by using molecular modeling where LMW chitosan is ribbon-like to rod-like in solution but becomes rod-like to spherical at the gas–liquid interface.  相似文献   

16.
Poly (vinyl chloride)/ethylene-vinyl acetate/montmorillonite (PVC/EVA/OMMT) composites were prepared by melt blending method. Two kinds of montmorillonites were organically modified by trimethyloctadecyl ammonium and dimethyl bis (hydrogenated tallow) ammonium, respectively. The morphology and tensile properties of the resultant composites were discussed in terms of the modifier type and OMMT content. The PVC/EVA/OMMT composites have intercalated structure, which is independent of the polarity of the modifiers, while the tensile properties show strong dependence on the modifier type. The OMMT modified by polar modifier gives higher tensile ductile and strength of PVC/EVA/OMMT composites.  相似文献   

17.
邓聪  王玉忠 《高分子科学》2014,32(1):98-107
Aluminum hypophosphite (AP) was used to prepare flame-retarded thermoplastic polyurethane (FR-TPU) composites, and their flame retardancy, thermal degradation and mechanical properties were investigated by limiting oxygen index (LOI), vertical burning test (UL-94), thermogravimetric analysis (TGA), cone calorimeter (CC) test, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and tensile test. TPU containing 30 wt% of AP could reach a V-0 rating in the UL-94 test, and its LOI value was 30.2. TGA tests revealed that AP enhanced the formation of residual chars at high temperatures, and slightly affected the thermal stability of TPU at high temperatures. The combustion tests indicated that AP affected the burning behavior of TPU. The peak of heat release rate (PHRR), total heat release (THR) and mass loss rate (MLR) greatly reduced due to the incorporation of AP. The tensile test results showed that both the tensile strength and the elongation at break slightly decreased with the addition of AP. The digital photos and SEM micrographs vitrified that AP facilitated the formation of more compact intumescent char layer. Based on these results mentioned above, the flame-retarding mechanism of AP was discussed. Both the self-charring during the decomposing process of AP and its facilitation to the charring of TPU led to the great improvement in the flame retardancy of TPU.  相似文献   

18.
The effective utilization of raw natural fibers as indispensable component in polymers for developing novel low-cost eco-friendly composites with properties such as acceptable specific strength, low density, high toughness, good thermal properties, and biodegradability is one of the most rapidly emerging fields of research in polymer engineering and science. In fact, raw natural fiber–reinforced composites are the subject of numerous scientific and research projects, as well as many commercial programs. Keeping in mind the immense advantages of raw natural fibers, in the present article we concisely review raw natural fiber/polymer matrix composites with particular focus on their mechanical properties.  相似文献   

19.
Elastomers are materials showing exceptional elasticity and are used for numerous applications. However, their low stiffness as well as their insulating behavior can be limiting so the incorporation of graphene-based materials can help and improve drastically their properties. With high Young's modulus, high electrical and thermal conductivities, graphene and graphene-like fillers seem ideal fillers to effectively tune elastomers properties. With low graphene-like loadings, most elasticity properties of elastomers could be preserved while increasing or adding new properties to the composites to enable new applications. Herein, we focus on the effects of “graphene” incorporation into elastomers and we will highlight the key parameters to effectively monitor the changes.  相似文献   

20.
The main objective of this article is to introduce a newly identified fish tail palm tree natural fiber as reinforcement in the development of partially biodegradable green composites. The tensile strength, tensile modulus, and impact strength of the composite are 1.54, 1.83, and 9.8 times greater than those of pure resin, respectively. The thermal conductivity of the composite decreased with increase in fiber content and the opposite trend was observed for temperature. The effect of temperature on specific heat capacity and thermal diffusivity of the composite was also considered and discussed.  相似文献   

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