Disproportionated rosin

In disproportionation, rosin is heated over a catalyst to transfer hydrogen, yielding dehydro (5) and dihydro (8) resin acids. The dehydro acids are stabilized by the aromatic ring the dihydro acids contain only an isolated double bond in place of the less stable conjugated double bonds. 

The most commonly used emulsifiers are sodium, potassium, or ammonium salts of oleic acid, stearic acid, or rosin acids, or disproportionate rosin acids, either singly or in mixture. An aLkylsulfate or aLkylarenesulfonate can also be used or be present as a stabilizer. A useful stabilizer of this class is the condensation product of formaldehyde with the sodium salt of P-naphthalenesulfonic acid. AH these primary emulsifiers and stabilizers are anionic and on adsorption they confer a negative charge to the polymer particles. Latices stabilized with cationic or nonionic surfactants have been developed for special apphcations. Despite the high concentration of emulsifiers in most synthetic latices, only a small proportion is present in the aqueous phase nearly all of it is adsorbed on the polymer particles. 

Dehydroabietic acid 1, the main resin acid of disproportionated rosin, is a readily available hydrophenanthrene derivative and a useful starting material for the synthesis of industrial and/or physiologically important products (1), by introduction of suitable substituents in the aromatic ring, such as the nitro or amino groups. 

The paper industry uses large amounts of the sodium salt of rosin as paper size, which accounts for the greatest single use of rosin. The synthetic rubber industry is the second most important user of rosin. In making styrene-butadiene rubber, disproportionated rosin soaps are used alone or in combination with fatty acid soaps as emulsifiers in the polymerization process. Disproportionation decreases the number of double bonds in the abietic acid of the rosin, making a more stable material. 

Emulsifiers for styrene-butadiene, styrene-butadine-acrylonitrile, and neoprene rubbers is the next important area of rosin use. Due to its unique properties of being surface active in aqueous solution and tacking in coagulated rubber, disproportionated rosin finds ready acceptance in this application. However, due to slow growth of SBR, which is by far the most important factor among all rubbers, the consumption of rosin here will rise only very slowly, if at all, in the future. It is significant to note that there appears to be an industry-wide acceptance of a mixed disproportionated rosin-fatty acid emulsifier, which is lower in manufacturing cost, to replace the traditional disproportionated rosin acid and soaps. 

DRA 1500. [TdioChem. Industry] POE disproportionated rosin ester eituilsi-fier, dispersaiL... 

Disproportionated rosin acid, potassium salt Disproportionated rosin, potassium soap EINECS 263-142-4 Potassium rosinate Potassium salt of wood rosin acids Potassium soap of rosin Resin acids and Rosin acids, potassium salts Rosin acids, potassium salts Rosin, disproportionated, potassium salt Rosin, potassium salt. 

Disproportionated rosin acid, sodium salt EINECS 263-144-5 Resin acids and Rosin acids, sodium salts Rosin acid, monosodium salt Rosin xids, sodium salt Rosin acids, sodium salts Rosin, disproportionated, sodium salt Rosin, sodium salt Rosin, sodium soap Sodium soap of disproportationed rosin Wood rosin, sodium salt... 

Disproportionated rosin acid, potassium salt 3129 Dithiothreitol 1510... 

Dehydroabietic acid methyl ester 1 was prepared by methylation with diazomethane [7] of the respective acid, obtained from commercially disproportionated rosin [8]. 

Chem. Desarip. Modified dehydrogenated (disproportionated) rosin CAS 8050-09-7 EINECS/ELINCS 232-475-7 Uses Thermoplastic resin in hot-melt-applied adhesives and coating tor paper and paperboard substrates as tackifier and processing aid tor rubber-based adhesives and molding compds. emulsifier tor emulsion polymerization plasticizer, softener, tackifier tor use in contact with food Features Pale, oxidation-resistant si. retards cure Pro rties USDA Rosin N solid, flakes sol. in alcohols, esters, ketones, min. spirits, and aromatic hydrocarbons dens. 1.058 kg/l R B soften, pt. 73 C flash pt. (COC) 209 C acid no. 154 sapon. no. 159... 

CAS 8050-09-7 8052-10-6 EINECS/ELINCS 232-475-7 Synonyms Colophane Colophonium Cotophony Disproportionated rosin Gum rosin Pine rosin Resin Rosin gum Wood rosin Yellow pine... 

Disponil SUS 1C 640. See Dicyclohexyl sodium sulfosuccinate Disponil TA 20. See Ceteareth-20 Disposorb . See Carbon, activated Disproportionated rosin. See Rosin Disproportionated tall oil fatty acid. See Tall oil acid... 

Synonyms Colophane Colophonium Colophony Disproportionated rosin Gum rosin... 

R = THE HYDROCARBON RADICAL FROM ANY ROSIN ACID, HYDROGENATED ROSIN ACID, DEHYDROGENATED OR DISPROPORTIONATED ROSIN ACID. 

Rosin dehydrogenation leads to the removal of hydrogen, which, after double bond rearrangement, converts abietadienoic acids into dehydroabietic acid [5, 8-11]. This reaction is normally carried out at high temperatures (200-300°C), often in the presence of catalysts like metals e.g. Pd, Ni), sulphur or iodine. The hydrogen thus released reacts in situ by adding to the pimaradienoic acids and, to a smaller extent, to the abietadienoic acids. Both reactions contribute to the rosin stabilization and these products are known as disproportionated rosins. 

Mayer M.I.I., Meuldijk 1., Thoenes D., Emulsion polymerization of styrene with disproportionated rosin acid soap as emulsifier, 7. Appl. Polym. Sci, 59(6), 1996, 1047. 

Synonyms disproportionated rosin gum rosin wood rosin pine rosin... 

Sodium disproportionated rosin Mixed tertiary mercaptans Potassium persulphate... 

Chem. Descrip. Disproportionated rosin Ionic Nature Anionic... 

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