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Carbonyl and carboxyl groups

The anomalous effect of the last two rubbers in the table with their low solubility parameters is possibly explained by specific interaction of PVC with carbonyl and carboxyl groups present respectively in the ketone- and fumarate-containing rubbers to give a more than expected measure of compatibility. It is important to note that variation of the monomer ratios in the copolymers and terpolymers by causing changes in the solubility parameter and eompatibility will result in variation in their effect on impact strength. [Pg.341]

The acid number is mainly defined for rosins and rosin-derived resins and for phenol-modified resins. Standard hydrocarbon resins have zero acid number because the absence of functional groups. However, the acid number allows one to control deterioration by oxidation with formation of carbonyl and carboxyl groups in hydrocarbon resins. Typical acid number values of different resin types are ... [Pg.615]

It has been shown that fairly quantitative solid-state spectra can be obtained for coals. With other polymers our experience indicates the same behaviour. Only in the case of highly polar groups, e.g. carbonyl and carboxyl groups, may difficulties be noted. [Pg.20]

The total emission In the commercial heat treatment of 5 to 8 hours at 170 to 160°C varied from 0.4 to 1.2% for CO2 and 0.05 to 0.2% for CO and 0.04 to 0.1% for total acids based on dry board. Some of this emission might emanate from pyrolysis of higher molecular weight material condensed and deposited on the walls of the heat treatment chamber. The heat of formation of this CO2 and CO Is about half the total heat release measured. Part of the oxidation products might remain in the solid phase within the board material, e.g. as bound carbonyl and carboxylic groups, partly followed by heat consuming dehydration reaction. [Pg.396]

Arachidic acid monolayers were prepared from a benzene solution on the water subphase of pH5.8(pure water) and 12.6(adjusted by addition of NaOH) at Tsp of 303 K below Tm(=328 K) of the monolayer [31]. The ionic dissociation state of hydrophilic group was estimated on the basis of the stretching vibrations of carbonyl and carboxylate groups by Fourier transform-infrared attenuated total reflection, FT-IR ATR measurements. 70 arachidic acid monolayers were transferred on germanium ATR prism, resulting in the formation of the multi-layered film. Transfer on the prism was carried out at surface pressures of 25 or 28 mN-nr1. Infrared absorption measurements revealed that almost carboxylic groups of arachidic acid molecules did not dissociate on the water subphase of pH5.8, whereas all carboxylic groups dissociated as carboxylate ions on the water subphase of pH 12.6. [Pg.26]

Although the sulfur trifluoride compounds are generally useful as selective agents for conversion of carbonyl and carboxyl groups to difluoromethylene and trifluoromethyl groups, variations in reaction conditions are often necessary.7 Thus the reaction of aromatic ketones requires heating at 150°. Since the reaction with aliphatic aldehydes and ketones is exothermic, it is advan-... [Pg.21]

Generation of carbonyl and carboxyl groups can also be achieved by plasma etching, which is a particularly useful technique because when applied in an inert atmosphere (e.g. N2) affords the introduction of basic functionalities [16]. [Pg.48]

Sodium naphthalene etching or Tetra Etch for PTFE improves the surface roughness and creates unsaturated bonds, carbonyl and carboxyl groups. [Pg.761]

Sterols are steroid alcohols. They have a P-positioned hydroxyl group at C-3 and one or more double bonds in ring B and in the side chain. There are no further oxygen functions, as in the carbonyl and carboxyl groups. [Pg.56]

Falcon 3001 (polystyrene which is treated by glow discharge to introduce carbonyl and carboxyl groups, giving the surface a certain hydrophilicity). [Pg.20]

Thus, bleaching of non-phenolic lignin derivatives is possible at both pH extremes, and conditions may be chosen according to process convenience. The formation of new functionality during color removal is inevitable, and this can be assessed by FTIR spectroscopy. Acidic conditions appear to result in the formation of carbonyl and carboxyl groups, and alkaline H2O2 is suggested to alter aromatic character. Hydroxylation and hydrolysis are encountered also. [Pg.447]

The IR spectra of these kerogens show high concentrations of carbonyl and carboxyl groups indicating strong oxidation of the organic matter. This alteration... [Pg.40]

The main causes for the formation of carbonyl and carboxyl groups in cellulose are isolation and purification procedures besides natural aging. This applies in particular to cellulosic pulps from wood, which has undergone a number of processing steps to be freed from lignin, hemicelluloses, and extractives. [Pg.3]

Fig. 1 Possible effects of carbonyl and carboxyl groups on macroscopic properties of cellulose... Fig. 1 Possible effects of carbonyl and carboxyl groups on macroscopic properties of cellulose...
During an alkaline oxygen stage the formation of keto structures by oxidation of ketols is postulated, finally leading to acids. Sodium permanganate treatments yield a moderate increase in both, carbonyls and carboxyl groups at short reaction times [20]. [Pg.6]


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Addition to cumulated carbonyl groups and carboxylate ions

Carbonyl carboxylate

Substitutions at the Carbonyl Group Reactions of Carboxylic Acids and Derivatives

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