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Adipoyl salts

The chemistry of synthetic jasmine materials was given an enormous boost in the 1930s when Nylon 66 was launched as a product. Nylon 66 is a polyamide prepared using adipoyl chloride and hexamethylenetetramine as monomers. The 66 in the name refers to the fact that there are 6 carbons in each type of unit that lies between the amide links in the polymer chain. Thus, adipic acid is the key feedstock for Nylon 66 and the introduction of the latter meant that the former became a basic chemical commodity. Pyrolysis of the calcium or barium salt of adipic acid produces cyclopentanone, and so the availability of large quantities of the acid meant that the ketone could also be prepared at low cost. [Pg.121]

Preparation of Macromolecular Dioxolenium Salts. Living polystyrene prepared by the polymerization of styrene in THF with a-methylstyrene tetramer dianion reacted with a 2.1-molar amount of ethylene oxide for three hours at room temperature a 6.6-molar amount of adipoyl chloride was added, and the mixture was stirred for 20 horns a 20-molar amount of ethylenebromohydrin was added. This mixture was stirred for 44 hours. The bromoethylated polystyrene was precipitated in excess methanol and freeze-dried from benzene in a vacuum system. A 1-nitropropane solution of polystyrene dioxolenium salt was prepared by reaction of bromoethylated polystyrene with silver perchlorate in 1-nitropropane. Silver bromide was removed from the reaction mixture by filtration. Molecular weight of the product was measured by a vapor-pressure osmometer it was 1910 for living polystyrene and 5190 for the bromoethylated polystyrene. Bromine analysis of the bromoethylated polystyrene showed 67.9% of the calculated value. [Pg.260]

Polytetramethylene glycol of molecular weight 2000 was freeze-dried from benzene in a vacuum. The bromoethylated prepolymer was obtained by reaction of the glycol, first with adipoyl chloride, then with ethylene bromohydrin (Table II) and precipitation in water and n-hexane. Nitromethane solution of the poly-THF dioxolenium salt was prepared after filtration of silver bromide from the reaction product of bromoethylated poly-THF with silver perchlorate in nitromethane. [Pg.260]

Anhydro-alditols - The preparations of polyesters based on l,4 3,6-di-anhydro-D-glucitol and -o-mannitol with succinyl-, glutaryl- and adipoyl-dichlor-ides have been reported. Also reported have been the syntheses of poly(1 6)-2,5-anhydro-D-glucitol and its 3,4-di-0-alkylated derivatives by Lewis acid induced polymerization of 3,4-di-0-alkyl-l,2 5,6-dianhydro-D-mannitol base induced polymerization of l,2 5,6-dianhydro-3,4-di-0-methyl- or 3,4-di-O-iso-propylidene-D-mannitol base induced polymerization of l,2 5,6-dianhydro-3,4-di-O-pentyl- or di-O-decyl-o-mannitol and base induced polymerization of l,2 5,6-dianhydro-3,4-di-0-methyl-L-iditol. The solubilities of these 3,4-di-O-alkylated and deprotected polymers in aqueous and organic media were studied. Further, it has been reported that 2,5-anhydro-3,4-di-0-methyl-D-glucitol linked 1,6 to silica gel was useful for the optical resolution of amines and amino acid salts. ... [Pg.226]

Won et al. [19], have reported synthesis of polyesters with valine, leucine, isoleucine, methionine, and phenylalanine (Table 12.1). This three-step process involves synthesis of a diester and a dinitro compound that are copolymerized [19], An amino acid is first coupled with a diol (with 3, 4, or 6 methylene groups) in the presence of tosyl to yield a diester with acid salts of diamine at the terminal ends. The second monomer, di-p-nitrophenyl ester of carboxylic acids, is synthesized by a condensation reaction of adipoyl or se-bacoyl chloride with p-nitro phenol. The final polymerization step involves an arduous condensation reaction in the presence of a strong proton abstractor between acid salt of bis(amino acid-alkyne diester) and di-p-nitrophenyl ester of dicarboxylic acids. Following along the same lines, Chu and Guo [22] have copolymerized a mixture of nitro phenyl ester of succinate, adipate, or sebacate and nitrophenyl fumarate with toluenesulfonic acid salt of phenylalanine butane-1,4-diester. The addition of fumarate derivative to the monomer mixture provides an unsaturated double bond in the polymer backbone that can be functionalized for specific biomedical... [Pg.210]

Fig. 2.6 Scheme illustrating the synthesis of polyesteramide following solution phase polycondensation. Monomer I Di(phenylalanine) adipamide prepared from L-phenylalanine and adipoyl chloride under Schotten-Baumann condition. Monomer II p-Toluenesulfonic acid salts of bis (amino acid)-1,4-butane diesters prepared by direct esterification of a-amino acids with 1,4-butanediol in presence of p-toluenesulfonic acid. Adapted from Ref. [24]... [Pg.29]


See other pages where Adipoyl salts is mentioned: [Pg.33]    [Pg.259]    [Pg.33]    [Pg.150]   
See also in sourсe #XX -- [ Pg.23 ]




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Adipoylation

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