Alteration by additives of physico-chemical properties of solids: Effect of admixed heterophase semiconductors on thermal stability of silver azide

1967 ◽  
Vol 7 (2) ◽  
pp. 201
Author(s):  
Y ZAKHAROV
2017 ◽  
Vol 864 ◽  
pp. 48-53
Author(s):  
Ahmad Fairoz Aziz ◽  
Khuzaimah Nazir ◽  
S.F. Ayub ◽  
N.I. Adam ◽  
Muhd Zu Azhan Yahya ◽  
...  

0.5 wt.% of N-(1,3-dimethylbutyl)-N’-phenyl-p-phenylenediamine (6PPD) was introduced into polymer electrolytes based on 30% poly(methyl-methacrylate) grafted natural rubber (MG30) in order to reduce the aging factor of MG30. The polymer electrolyte without 6PPD was used as control. All samples were prepared by using solution cast techniques. The effect of 6PPD in the electrolytes was analysed by using TGA, DSC and FTIR. TGA and DSC results revealed the thermal stability of MG30 electrolytes with 6PPD have higher thermal stability but lower glass transition temperature value. FTIR studies confirmed the existence of LiTF in the sample and prove the occurrence of polymer-salt complexation. Deconvolution techniques analysis on FTIR spectra shows the electrolyte sample with 6PPD display more ion dissociation which reflects to higher ionic conductivity.


1993 ◽  
Vol 5 (4) ◽  
pp. 307-316 ◽  
Author(s):  
B S Bhonsale ◽  
S N Kaula ◽  
B V Patel ◽  
K C Patel

Various polycynaurates were synhesised by stirred interfacial polycondensation of 2-(N.N-diphenynhydrazino)-4,6-dichloro-s-triaziae (DPHDCT) with each of the aromatic diols: bisphenol-A (BPA); bisphenol-C (BPC); bisphenol-S (BPS); phenolphthalein (Ph); catechol; resorcinol; 1,5and 2.7-dihydroxynaphthalene (DHN-1,5 and DHN-2,7) and 1,8-dihydroxyanthraquinone (DHA-1,8). Interfacial polycondensation of DPHDCT with BPA was investigated in detail in order to select optimum reaction conditions. The yield of polycyanurates varies from 6 I% to 79%. The polycyanurates are soluble in chlorinated solvents such as chloroform, dichloroethane. dichloromethane and chlorobenzene. The reduced viscosity for polycyanurates, determined with a 1 g disolution in chloroform at 25 + 3°C was found to be in the range 0.50-0.68 dl g. All the polycyanurates were characterized by IR spectra. The densities of the polycyanurates, determined using the suspension method at 25 3°C, range between 1.196 and 1.330 g cm. The overall reactivity of diols, based on reduced viscosity values, was found to decrease in the following order: PCBPA> PCPh> PCBPC> PCR>PCDHN-2,7 > PCDHN-I,5 > PCC > PCDHA-1.8 > PCBPS. The thermal stability of polycyanurates, derived from various temperature characteristics, was found to decrease in the following order: PCBPA> PCBPS> PCBPC > PCC PCR> PCDHN-2,7 PCDHN-.l 5 > PCDHA-1,8 > PCPh.


2019 ◽  
Vol 20 (1) ◽  
pp. 77-82
Author(s):  
A.L. Stepura ◽  
O.I. Aksimentyeva ◽  
P.Yu. Demchenko

Features of crystal structure, electrical conductivity and thermal stability of poly-ortho-toluidine (PoTi) samples, obtained with method of oxidative polymerization in the environment of sulfuric and toluenesulfonic acids (TSA), were investigated. It was discovered that PoTi-TSA samples are characterized withhigh crystallinity. According to the physico-chemical analysis, doping samples with TSA causes increase of PoTi thermal stability, electrical conductivity and sensor sensitivity on the contrary to samples doped with sulfuric acid. Based on temperature dependence of specific resistance, were calculated the values of the conductivity activation energy, which are within the limits of 0.2-0.4 eV depending on the type of dopant.


2014 ◽  
Vol 104 ◽  
pp. 223-230 ◽  
Author(s):  
Djalal Trache ◽  
André Donnot ◽  
Kamel Khimeche ◽  
Riad Benelmir ◽  
Nicolas Brosse

1996 ◽  
Vol 8 (2) ◽  
pp. 265-273 ◽  
Author(s):  
K C Patel ◽  
S N Kaula ◽  
P S Patel

Several homopolycyanurates were synthesized by stirred interfacial polycondensation of 2-morpholino-4,6-dichloro- s-triazine with various aromatic diols such as 1,5- dihydroxynaphthalene,(DHN-1,5),1,7-dihydroxynapthalene(DHN-1,7),2,7-dihydroxynapthalene resorcinol (R), catechol (C), hydroquinone (H) and phenolphthalein (Ph). They were characterized by density, viscosity measurements, IR spectra, solubility tests and thermogravimetric analysis. The polymer had reduced viscosities in the range 0.468 to 0.829 dl g−1 in chromoform at 30 °C. All the polymers were amorphous and soluble in chlorinated solvents. The thermal stability of polycyanurates decreases in the following matter: PCDHN-1,5 > PCDHN-1,7 > PCPh > PCR ≃ PCDHN-2,7 > PCHQ > PCC.


1981 ◽  
Vol 36 (11) ◽  
pp. 1444-1450 ◽  
Author(s):  
Max Schmidt ◽  
Erich Sametschek

Abstract The first examples of the hitherto unknown 1,2,4-Trithia-3,5-diborolanes with B-O-C-bonds have been synthesized and characterised. The diiodo substituted ring (2) reacts with 2,6-dimethylphenol, to form 3,5-bis-(2,6-dimethylphenyloxi)-1,2,4-trithia-3,5-di-borolane (3) and HI. 3,5-Diethoxi-1,2,4-trithia-3,5-diborolane, 5, and C2H5I are formed via the cleavage of diethylether by 2. From 2 and diisopropylether, the corresponding 3,5-diisopropyloxi-1,2,4-trithia-3,5-diborolane (6) is formed. The unsymmetrical ethers methyl-t-butylether and methylphenylether undergo reactions with 2 resulting in the formation of 3,5-dimethyloxi-1,2,4-trithia-3,5-diborolane (8) (besides t-C4H9I) and 3,5-diphenyloxi-1,2,4-trithia-3,5-diborolane (10) (besides CH3I). The thermal stability of the new compounds is increasing with increasing size of R in the -OR group and from aliphatic to aromatic R in this group. IR, Raman, 1H NMR and 11B NMR spectra of the compounds are reported as well as some physical and chemical properties.


2012 ◽  
Vol 727-728 ◽  
pp. 609-613
Author(s):  
P.C.F. Menezes ◽  
Taciana Regina de Gouveia Silva ◽  
Ana Cristina Figueiredo de Melo Costa ◽  
Edcleide Maria Araújo

The research in composites attempt to predict the physico-chemical and mechanical a given mixture of materials. In this work, a composite was produced using as the polyamide 6 matrix and how the burden of nickel ferrite was incorporated as powders calcined at 1200°C and concentration of 50 wt.%. This mixture was compacted in a hydraulic press with heating and characterized by XRD, SEM and TG. XRD results showed the characteristic peaks of polyamide 6 and ferrite. SEM results showed a good dispersion of nickel ferrite loading in the matrix, the presence of larger clusters and evenly distributed load for the composite calcined at 1200 ° C. TG curves showed that the addition of loading of calcined nickel ferrite promoted an increase in thermal stability of the composite compared to pure polyamide.


2014 ◽  
Vol 604 ◽  
pp. 192-195 ◽  
Author(s):  
Kristine Salma-Ancane ◽  
Liga Stipniece ◽  
Zilgma Irbe ◽  
Marina Sokolova ◽  
Guna Krieke ◽  
...  

β-Tricalcium phosphate bioceramics with small, close to bone-like amounts of Mg were obtained by modified precipitation method and following sintering. The effect of small amounts of Mg on the thermal stability, microstructure and sintering behavior of β-tricalcium phosphate bioceramics was evaluated. Addition of small amounts of Mg, can induce a remarkable effect on the physic-chemical properties of β-TCP and therefore the chemical composition of the starting materials should be controlled.


2014 ◽  
Vol 10 (9) ◽  
pp. 2744-2753 ◽  
Author(s):  
Fang Gao ◽  
Kay Lockyer ◽  
Karena Burkin ◽  
Dennis T Crane ◽  
Barbara Bolgiano

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