Dicarboxylic aliphatic 226

Organic Acid Salts. Slightly soluble or insoluble silver salts are precipitated when mono- and dicarboxylic aliphatic acids or their anions are... 

Effect of the molecular weight on the characteristics of phase transitions. This effect was found in studying some polyethers of different structure in the region of low molecular weights [S, 6]. The study of nematic polyethers based on 4,4 -dihydroxy-2,2 -dimethylazoxybenzene and dicarboxylic aliphatic acids [43] with from 1000-3000 to 20,000-30,000 showed that the values of T-i are essenti ly dependent on M up to values of approximately 10,000 and stop being dependent on M with lower values, from... 

Table 4. Experimental conditions and weight percent of original organic matter converted to oxalic (Q), succinic (C4), pyrotartaric (C5), glutaric (C5), iso-adipic (Q), adipic (C6), pimelic (C7), suberic (Cg), azelaic (C9), and sebacic (Ciq) acids at maximum generation of total dicarboxylic aliphatic acids...

Nylon A class of synthetic fibres and plastics, polyamides. Manufactured by condensation polymerization of ct, oj-aminomonocarboxylic acids or of aliphatic diamines with aliphatic dicarboxylic acids. Also rormed specifically, e.g. from caprolactam. The different Nylons are identified by reference to the carbon numbers of the diacid and diamine (e.g. Nylon 66 is from hexamethylene diamine and adipic acid). Thermoplastic materials with high m.p., insolubility, toughness, impact resistance, low friction. Used in monofilaments, textiles, cables, insulation and in packing materials. U.S. production 1983 11 megatonnes. 

As with poly(ethylene terephthalate) PBT-based copolymers have been introduced to overcome some of the deficiencies of the homopolymer. For example, the rather low notched impact strength of unreinforced grades has been overcome by partial replacement of the terephthalic acid with a longer chain aliphatic dicarboxylic acid. Improved toughness has also been obtained by grafting about 5% of ethylene and vinyl acetate onto the polyester backbone. 

Bromophenol blue (3.0...4.6) aliphatic carboxylic acids [225 — 228] malonic and lactic acids [229] palmitic and lactic acids [230] malonic, glycolic, malic, citric, tartaric, ketoglutaric, galacturonic and oxalic acids [196] dicarboxylic acids, succinic acid [231] indoleacetic acid, trichloroacetic acid [232] palmitic acid, palmityl- and stearyllactic acid [223] benzoic, sorbic and salicylic acid [234] metabolites of ascorbic acid [235] chloropropionic acid [236] oligogalacturonic acids [237] amino acids, hydrocarbons, mono-, di- and triglycerides [238] xylobiose, xylose, glucose and derivatives [239] sugar alcohols [91] toxaphene [240]... 

One of the most actively investigated aspects of enamine chemistry has been the acylation process (i). Initial intensive studies by Hiinig (373-375) showed the ease of preparing a variety of 9-diketones and particularly the synthetic potential of acylated cyclic ketones as intermediates in the preparation of aliphatic keto acids, keto dicarboxylic acids and diketo dicarboxylic acids (376-378). 

Some of the typical conditions of polycondensations used for aliphatic and aromatic monomers are not suitable for furan derivatives, e.g., the melt polycondensation of 2,5-furan dicarboxylic acid chloride with 2,5-b/s(hydroxymethyl) furan at about 80 °C only yields a black insoluble product5. The hydrochloric acid liberated in the reaction is clearly responsible for the charring of the furanic diol which like its simpler homologue furfuryl alcohol, resinifies rapidly in acidic media (see below). 

From the preceding discussion, it is easily understood that direct polyesterifications between dicarboxylic acids and aliphatic diols (Scheme 2.8, R3 = H) and polymerizations involving aliphatic or aromatic esters, acids, and alcohols (Scheme 2.8, R3 = alkyl group, and Scheme 2.9, R3 = H) are rather slow at room temperature. These reactions must be carried out in the melt at high temperature in the presence of catalysts, usually metal salts, metal oxides, or metal alkoxides. Vacuum is generally applied during the last steps of the reaction in order to eliminate the last traces of reaction by-product (water or low-molar-mass alcohol, diol, or carboxylic acid such as acetic acid) and to shift the reaction toward the... 

Trinitrochlorobenzene (piciyl chloride) in pyridine-A -mcthylpyrrolidi-none (NMP) solutions were later used for the preparation of polyesters from dicarboxylic acids and diphenols or aliphatic diols,309 but better results have been obtained with sulfonyl chlorides and phosphorus compounds. 

Polymers with hetero-atoms in the chain are suitable for chemical recycling of waste materials. In addition to depolymerisation (nylon 6) and solvolysis (nylon 6,6, PETP, PU) the degradation of aliphatic polyamides with dicarboxylic acids, diamines and cyclic anhydrides, especially trimellitic anhydride, becomes more and more important. The utilisation of the obtained fragments is described. 

A dispersant that can be used in drilling fluids, spacer fluids, cement slurries, completion fluids, and mixtures of drilling fluids and cement slurries controls the rheologic properties of and enhances the filtrate control in these fluids. The dispersant consists of polymers derived from monomeric residues, including low-molecular-weight olefins that may be sulfonated or phosphonated, unsaturated dicarboxylic acids, ethylenically unsaturated anhydrides, unsaturated aliphatic monocarboxylic acids, vinyl alcohols and diols, and sulfonated or phosphonated styrene. The sulfonic acid, phosphonic acid, and carboxylic acid groups on the polymers may be present in neutralized form as alkali metal or ammonium salts [192,193]. 

M. Hofinger and H. Schellenberg. Process for the preparation of polycondensation products from alkoxylated fatty amines, diols and aliphatic dicarboxylic acids (Verfahren zur Herstellung von Polykon-densationsverbindungen aus oxalkylierten Fettaminen, Diolen und Aliphatischen Dicarbonsauren). Patent EP 299348,1989. 

Wilkins, A. L., Lu, Y., and Tan, S. T. (1995). Extractives from New Zealand honeys 5. Aliphatic dicarboxylic acids in New Zealand rewarewa (Knightea excelsa) honey. /. Agric. Food Chem. 43, 3021-3025. 

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