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Dicarboxylic acids from diols

Using HF-SbF5, Yoneda et al.405 have obtained dicarboxylic acids from diols by reaction with CO under mild conditions. Some cyclization products were also obtained. Scheme 5.40 was suggested for the reaction. [Pg.620]

Various organic plasticizers having boiling points over 300 °C are available, such as di(2-ethylhexyl) phthalate (4a), di(2-ethylhexyl) adipate (8), oligomers formed from dicarboxylic acids and diols with molecular weights ranging up to 3500, esters of tri-mellitic acid, epoxidised fatty acids or organic phosphates, such as tris(2-ethylhexyl) phosphate (9) or (2-ethylhexyl) diphenyl phosphate (10). Most phosphates also function as flame retardants and some, such as 10, are smoke suppressants as well (Meier, 1990). [Pg.53]

In the polycondensation of aliphatic dicarboxylic acids with diols, DCC is used to mediate the reaction. In this manner biodegradable and surface active aliphatic polyesters are obtained. Also, hydroxycarboxylic acids derived from maleic or succinic acid are ho-mopolymerized in the presence of EDCCl in DMF at room temperature. In this manner... [Pg.268]

Vicinal diols are also oxidized to carboxylic acids. 1,2-Dihydroxydec-ane in benzonitrile shaken with oxygen at atmospheric pressure at 100 °C in the presence of cobalt laurate as a catalyst furnishes, after 2 h, a 66% yield of pelargonic (nonanoic) acid [69]. Electrolysis at 20-30 °C in aqueous potassium carbonate with nickel electrodes in an undivided cell and a current of 0.3 A yields 74-84% of dicarboxylic acids from both cis and trans cyclic diols having six to eight carbons in the rings (equation 307) [122]. [Pg.163]

The diisocyanates are used mainly in the manufacture of polyurethanes (PUR). These are produced by polyaddition of diisocyanates and dihydric alcohols, in particular the polyether alcohols (i.e., polyethylene glycols, polypropylene glycols, and the reaction products of propylene oxide with polyhydric alcohols). In addition, oligomeric esters from dicarboxylic acids and diols (polyester alcohols) are also used [91] ... [Pg.211]

Okumara et al. [10] were the first to attempt the enzyme-catalyzed synthesis of oligoesters from a reaction between dicarboxylic acids and diols. Gutman et al. [11] reported the first study on polyester synthesis by enzyme-catalyzed polymerization of A-B type monomers. Two independent groups in 1993 [12, 13] were first to report enzyme-catalyzed ring-opening polymerization (ROP). Their studies focused on 7- and 6-membered unsubstituted cyclic esters, e-caprolactone (e-CL) and 8-valerolactone (8-VL), respectively. [Pg.84]

Zhu, C., Zhang, Z., Liu, Q. et al. (2003) Synthesis and biodegradation of aliphatic polyesters from dicarboxylic acids and diols. Journal of Applied Polymer Science, 90 (4), 982-990. [Pg.271]

In the late 1920s W. Carothers and his research group at DuPont investigated the formation of polyesters from the condensation polymerization of aliphatic dicarboxylic acids with diols. These aliphatic polyesters were found to be inadequate as... [Pg.9]

Therefore, polyesters can be made by reacting dicarboxylic acids with diols, e.g. propanedioic acid and ethane -1,2-diol. The most common polyester fibre is Terylene . Terylene is made from benzene-1,4-dicarboxylic acid and ethane-1,2-diol. The conditions required are a catalyst such as antimony(III) oxide at a temperature of about 280 °C ... [Pg.431]

More recently we have shown Aat oligomeric polyesters form in aqueous oil-in-water (o/w) emulsion from molten mixtures dicarboxylic acids and diols below 100°C (14,15). In this case the emulsion particles served as a hydrophobic phase and catalysts were surface-active sulfonic acids. The method was restricted, however, to water-insoluble monomers that were liquid at the polymerization tenq)erature. [Pg.333]

Polyesters from diols and dicarboxylic acids (polyester fibres). [Pg.1019]

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... [Pg.61]

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. [Pg.78]

Dicarboxylic acids or esters thereof are recovered from solid phase polyester materials, such as post-consumer products and factory scrap, by subjecting the polyester to at least two hydrolysis stages in at least the first of which the amount of water used is substantially less than needed to effect total conversion of the polyester to the dicarboxylic acid. Also the diol content is controlled in the course of carrying out the hydrolysis. The hydrolysis reactions may be preceded by reaction of the polyester with a diol, the resulting depolymerisation products then being hydrolysed. [Pg.53]

A novel chemoenzymatic route to polyester polyurethanes was developed without employing highly toxic isocyanate intermediates. First, diurethane diols were prepared from cyclic carbonates and primary diamines, which were subsequently polymerized with dicarboxylic acids and glycols by using lipase CA as catalyst, yielding the polyurethanes under mild reaction conditions. [Pg.227]

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 ... [Pg.1019]

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]. [Pg.311]

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. [Pg.405]

There has in the past been some confusion in the use of the term alkyd, which is said to have been derived from alcohol plus acid. The definition offered by Kienle [1], discussed later, is broad enough to include all polyesters derived essentially from diols and dicarboxylic acids, and consequently linear polyesters were initially included in this class of polymer. On the other hand, Bjorksten et al. [2], in their 1956 compilation of published information about polyesters, restrict the term polyester to the polycondensation products of dicarboxylic acids with dihydroxy alcohols, and say that this definition does not include materials commonly known as alkyds . At the present time, there are still problems of nomenclature in the fibre field arising from the use of polyester as a generic term to cover fibres containing only a very restricted range of chemical groups. [Pg.4]

Wick, G. and Zeitler, H., Cyclic oligomers in polyesters from diols and aromatic dicarboxylic acids, Angew. Makromol. Chem., 112, 59 (1983). [Pg.140]

Propanediol. Both the diol and the dicarboxylic acid components of poly-trimethylene-terephthalate, a high performance polyester fiber with extensive applications in textile apparel and carpeting, are currently manufactured from petrochemical raw materials. [Pg.41]

The oxidation of propargyl alcohol to the acid and of but-2-yne-l,4-diol to acetylene dicarboxylic acid is carried out on a technical scale at a lead dioxide anode in sulphuric acid [4, 5]. Electrochemical oxidation of acetylenic secondary alcohols to the ketone at lead dioxide in aqueous sulphuric acid [4], gives better results than the cliromic acid based process of Jones [6], Oxidation of aminoalkan-1-ols to the amino acid at a lead dioxide anode in sulphuric acid is achieved in 31 -73 % 5delds [7]. This route is applied to the technical scale production of (l-alanine from 3-aminopropanol in an undivided cell [8]. [Pg.262]

The formation of polyesters from a dialcohol (diol) and a dicarboxylic acid (diacid) is used to illustrate the stepwise kinetic process. Polymer formation begins with one diol molecule reacting with one diacid, forming one repeat unit of the eventual polyester (structure 4.3) ... [Pg.85]

Polycondensation of diols with dicarboxylic acids is often performed in the melt. However, it does not always lead to high-molecular-weight polyesters. Sometimes, the starting materials or the resulting polyester are thermally unstable at the high condensation temperatures. If the reactants and the polyester are well soluble, one can carry out the polycondensation in solution (see Example 4-2). The elimination of water from diols and dicarboxylic acids frequently occurs rather slowly. In such cases suitable functional derivatives of the diols and dicarboxylic acids (esters or anhydrides) can be used instead of the direct condensation, as described in Sect. 4.1.1.3. [Pg.272]

Preparation of a Low-Molecular-Weight Branched Polyester from a Diol, a Triol and a Dicarboxylic Acid by Melt Condensation... [Pg.272]

Preparation of a High-Molecular-Weight Linear Polyester from a Diol and a Dicarboxylic Acid by Condensation in Soiution... [Pg.274]


See other pages where Dicarboxylic acids from diols is mentioned: [Pg.208]    [Pg.208]    [Pg.269]    [Pg.1316]    [Pg.99]    [Pg.79]    [Pg.257]    [Pg.388]    [Pg.265]    [Pg.1217]    [Pg.128]    [Pg.55]    [Pg.394]    [Pg.147]    [Pg.258]    [Pg.157]    [Pg.20]    [Pg.8]    [Pg.21]    [Pg.288]    [Pg.57]    [Pg.272]    [Pg.277]   
See also in sourсe #XX -- [ Pg.219 ]




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Diols dicarboxylation

Diols dicarboxylic acid

From 1,3-diols

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