Polycarboxylic adds

Physical properties for naphthalene mono-, di-, tn-, and tetracarboxylic adds are summarized in Table 8. Most of ihe naphthalene di- or polycarboxylic adds have been made by simple routes such as the oxidation of appropriate di- or polymethylnaphthalenes, or by complex routes, e.g,. the Sandmeyer reaction of the selected aminonaphthalenesulfonic add, to give a cyanonaphthalenesulfonic acid followed by fusion of the... 

Even when the charging effect is considered, the pKa of soil organic matter, unlike the pKa of a monoprotic add, tends to decrease as the ionic strength (salt concentration) of the soil solution is increased. This means that soil organic matter seems to be more acidic in more concentrated salt solutions. Synthetic polycarboxylic adds also show this behavior. It becomes clear that the application of solution concepts such as pK to complex charged polymeric solids has numerous pitfalls. 

Several investigations have been carried out to modify starch catalytically with the aim of obtaining specific hydrophilic properties. For example, selective oxidation of the hydroxymethyl groups of starch molecules leads to polycarboxylic adds, which can be used as adsorbers in diapers (nappies). A suitable catalyst for the synthesis of... 

The mechanism of high-temperature, base-catalyzed esterification involves cyclic anhydride formation by the polycarboxylic add, followed by base-catalyzed reaction of anhydride groups with cellulosic hydroxyls. Fumaric add, which cannot form a cyclic anhydride because of the irons arrangement of the two carboxyl groups, fails to react with cotton in the presence of weak bases and heat. 

Chem. Descrip. Sol n. of a lower m.w. unsat. acidic polycarboxylic add polyester with a polysiloxane copolymer in alkylbenzene solv. 

Chem. Descrip. Unsat. polycarboxylic add polymer with 36% xylene, 9% ethylbenzene, 3% 2,6-dimethyl-4-heptanone, 2% 4,6-dimethyl-2-heptanone... 

The catalyst comprises Ti, Zr, or V MgCU an alkyl A1 compound and optionally an electron donor compound, e.g., alkyl, cycloalkyl, or aryl esters of polycarboxylic adds (phthalic or succinic)... 

The procedure chosen for the calculation of the degree of linkage (0) and the stability constant of the complex (K) for a polycarboxylic add and an electron-donating polymer is indicated by the following equations for complexes with stoichiometric composition... 

The synthetic rubber products based on polyester-polyurethanes ate broken down in a definite way by alkali fusion to polyamines, polyols and polycarboxylic adds. The best reaction temperatures for separating are 300 °C for polyatnines, 180 °C for polyols and ca. 260 °C for polycarboxylic adds. Table 19 gives a survey. 

Chem. Descrip. Sodium salt of polycarboxylic add with wetting agent Ionic Nature Anionic... 

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