Ethylene dicarboxylation

Ethylene—Dicarboxylic Acid Copolymers. Partial neutralization of copolymers containing carboxyls in pairs on adjacent carbons, eg, ethylene—maleic acid, has been described (11). Surprisingly, there is no increase in stiffness related to neutralization. Salts with divalent metal cations are not melt processible. The close spacing of the paired carboxyl groups has resulted in ionic cluster morphology which is distinct from that of the commercial ionomer family. 

Attack on Saturated Carbon. - Ethylene dicarboxylic diphosphonic acid (EDCP, 2) has been prepared in 70% yield from 2,3-dichlorosuccinic anhydride (3) and trimethyl phosphite, followed by hydrolysis of the Arbuzov product. Tris(trimethylsilyl) phosphite, in contrast to trialkyl phosphites, attacks an oxirane carbon of epibalohydrins (4) to give the phosphonates (5). Bis(trimethylsilyl) phosphonite (6) has previously been prepared in situ and used to obtain y-ketophosphinic acids similar reactions with simple alkyl halides to give alkylphosphinic and dialkylphosphinic acids acids in high yields have now been described. ... 

Fumaric acid INS No 270, FW 116.07, Chem. name trani-bntanedioic acid, trans-l,2-ethylene-dicarboxylic acid. Fumaric acid is naturally found in rice, sngar cane, wine, plant leaves, bean sprouts, and edible mushrooms in small amonnts (is an intermediate in the tricarboxylic acid (Krebs) cycle), and is also produced in sun-exposed skin. The fnnctional nses are as an acidity regnlator and a flavoring agent. The ADI is not specified for fnmaric acid. The ferrons salt of fumaric acid can be used as iron fortifier. The common application areas inclnde bakery, confectionary, and drinks. It can also be used by mixing with other acidifiers. 

The procedure (with ethylene dibromide replacing trimethyleiie dibromide) described for cycZobutanecarboxylic acid (previous Section) does not give satisfactory results when applied to the cyclopropane analogue the yield of the cyclopropane-1 1 dicarboxylic acid is considerably lower and, furthermore, the decarboxylation of the latter gives a considerable proportion (about 30 per cent.) of butyrolactone ... 

The principal polymers to be described are poly(butylene terephthalate) [26062-94-2] (PBT) poly(ethylene terephthalate [25038-59-9] (PET) poly(cyclohexanedimethylene terephthalate) [24936-69-4] (CHDMT), and mention will be made of poly(ethylenenaphthalene-2,6-dicarboxylate)... 

The direct combination of selenium and acetylene provides the most convenient source of selenophene (76JHC1319). Lesser amounts of many other compounds are formed concurrently and include 2- and 3-alkylselenophenes, benzo[6]selenophene and isomeric selenoloselenophenes (76CS(10)159). The commercial availability of thiophene makes comparable reactions of little interest for the obtention of the parent heterocycle in the laboratory. However, the reaction of substituted acetylenes with morpholinyl disulfide is of some synthetic value. The process, which appears to entail the initial formation of thionitroxyl radicals, converts phenylacetylene into a 3 1 mixture of 2,4- and 2,5-diphenylthiophene, methyl propiolate into dimethyl thiophene-2,5-dicarboxylate, and ethyl phenylpropiolate into diethyl 3,4-diphenylthiophene-2,5-dicarboxylate (Scheme 83a) (77TL3413). Dimethyl thiophene-2,4-dicarboxylate is obtained from methyl propiolate by treatment with dimethyl sulfoxide and thionyl chloride (Scheme 83b) (66CB1558). The rhodium carbonyl catalyzed carbonylation of alkynes in alcohols provides 5-alkoxy-2(5//)-furanones (Scheme 83c) (81CL993). The inclusion of ethylene provides 5-ethyl-2(5//)-furanones instead (82NKK242). The nickel acetate catalyzed addition of r-butyl isocyanide to alkynes provides access to 2-aminopyrroles (Scheme 83d) (70S593). 

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. 

For the ordinary Diels-Alder reaction the dienophile preferentially is of the electron-poor type electron-withdrawing substituents have a rate enhancing effect. Ethylene and simple alkenes are less reactive. Substituent Z in 2 can be e.g. CHO, COR, COOH, COOR, CN, Ar, NO2, halogen, C=C. Good dienophiles are for example maleic anhydride, acrolein, acrylonitrile, dehydrobenzene, tetracya-noethylene (TCNE), acetylene dicarboxylic esters. The diene preferentially is of the electron-rich type thus it should not bear an electron-withdrawing substituent. 

The aromatization of the oxepin structure can be accompanied by other acid-catalyzed reactions such as the hydrolysis of ketals. Dimethyl 11 -oxo-6-oxabicyclo[5.4.0]undeca-l (7),2,4-triene-2,3-dicarboxylate ethylene ketal reacts in the presence of trifluoroacetic acid to give the tetralone system 3.133... 

Linear step-growth polymerizations require exceptionally pure monomers in order to ensure 1 1 stoichiometry for mutually reactive functional groups. For example, the synthesis of high-molecular-weight polyamides requires a 1 1 molar ratio of a dicarboxylic acid and a diamine. In many commercial processes, the polymerization process is designed to ensure perfect functional group stoichiometry. For example, commercial polyesterification processes often utilize dimethyl terephthalate (DMT) in the presence of excess ethylene glycol (EG) to form the stoichiometric precursor bis(hydroxyethyl)terephthalate (BHET) in situ. 

Explain the process of condensation polymerization. How might the polymer obtained from benzene-1,2-dicarboxylic acid and ethylene glycol differ from Dacron ... 

Polymerisation of a diol with a dicarboxylic acid is exemplified by the production of a polyester from ethylene glycol and terephthalic acid either by direct esterification or by a catalysed ester-interchange reaction. The resulting polyester Terylene) is used for the manufacture of fibres and fabrics, and has high tensile strength and resiliency its structure is probably ... 

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]. 

Block polymers or copolymers of ethylene oxide and 1,2-propylene oxide can be chain extended or crosslinked, respectively, with diisocyanates, dicarboxylic acids, formaldehyde, and diglycidyl ethers [108]. 

In general, polyalkylene polyamides-amines are obtained by the condensation of polyalkylenepolyamines with dicarboxylic acids. The materials are alkoxylated with an excess of ethylene oxide or propylene oxide or 1,2-butylene oxide [149],... 

Figure 4. Effect of radiation on the poly(ethylene terephthalate-co-2,6-naphthalene-dicarboxylate) yarns mole % of 2,6-DMN (%) 0.0 (X) 0.5 fA) 1-0 (O) 2.0 ...

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