Carboxylic acid high-molecular-weight

Beginning with 9-fluorene carboxylic acid, high molecular weight poly(9-hydroxy methyl-9-fluorene carboxylic acid) has been prepared by the homopolymerization of 9-hydroxymethyl-9-fluorene carboxylic acid using trifluoro methanesulfonate as the catalyst. This polymeric agent readily formed donor-acceptor complexes with 1,3-dinitrobenzene and is suitable as a charge transport material. 

About half of the dissolved organic carbon may appear in humic or fulvic acids. These are high-molecular weight organic compounds of a composition which is somewhat uncertain. They contain aromatic hydroxyl and carboxyl groups which have the ability to bind to metal ions. Rivers and estuaries typically contain 10 mg/liter of acid with an exchange capacity of 5-10 mmol/g, mainly due to carboxylic... 

An implication of the kinetic analysis presented in Sec. IV.A is that the rate of chain scission of polyesters can be retarded by endcapping to reduce the initial carboxylic acid end-group concentration. Alternatively, the rate may be increased by acidic additives that supplement the effect of the carboxy end groups. The first expectation was confirmed by partial ethanolysis of high molecular weight... 

Although the order of affinity of PF-4 for different glycosaminogly-cans, and dissociation of their complexes with salts, are typical of nonspecific, electrostatic interactions, PF-4 is not strictly a cationic protein.452 It is probable that heparin binds to clusters of basic amino acids (two lysine pairs) near the carboxyl terminal of a polypeptide chain that has an overall preponderance of acidic amino acid residues.457 High-molecular-weight heparin species can bind two PF-4 molecules, with formation of complexes 10 to 100 times as strong as those with antithrombin.217... 

The separation of rhodium hydride complex from a stream comprising catalyst and high molecular weight aldehyde condensation products using a carboxylic acid functionalized ion exchange resin in illustrated schematically in Figure 2.12. 

Current interest in synthetic fuels production by Fischer-Tropsch (FT) reactions have created a need for removal of byproduct oxygenates, formed by the FT reaction. The oxygenates consist of primary and internal alcohols, aldehydes, ketones, esters and carboxylic acids. The hydrocarbon products derived from the FT reaction range from methane to high molecular weight paraffin waxes containing more than 50 carbon atoms. 

Various combinations of reactant(s) and process conditions are potentially available to synthesize polyesters [Fakirov, 2002 Goodman, 1988], Polyesters can be produced by direct esterification of a diacid with a diol (Eq. 2-120) or self-condensation of a hydroxy carboxylic acid (Eq. 2-119). Since polyesterification, like many step polymerizations, is an equilibrium reaction, water must be continuously removed to achieve high conversions and high molecular weights. Control of the reaction temperature is important to minimize side reactions such as dehydration of the diol to form diethylene glycol... 

Anionic polyelectrolytes have been shown to enhance resistance to bacteria and fungi, enhance immune response, inhibit adjuvent arthritis and either depress or stimulate phagocytic activity of the reticuloendothelial system [458,459]. Carboxylic acid polymers have shown interferon induction, antiviral activity, and tumor growth inhibition [460]. The effects include inhibition of sarcoma, leukemia, polyoma and vesicular stomatitis virus. In one application, the cytotoxicity of bleomycin toward cultured mammalian cells was synergisti-cally enhanced by stirring in the presence of high molecular weight polyfacrylic acid) [461]. 

The tendency for PVC to degrade by the unzipping type of dehydrochlorination is reduced by the presence of heat stabilizers, such as barium and cadmium salts of high-molecular-weight carboxylic acids and epoxidized unsaturated aliphatic esters. The general reaction for cadmium salts is as follows ... 

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