Patent GB-652370-A (GB)
Title: Improvements in or relating to the treatment of abietyl compounds
IPC: C09F1/00
Filed: 1947-07-16
Abstract: Abietyl compounds in the form of rosin acids salts, esters, ethers, ester-ethers, and alcohols having either a single double bond or a conjugated system containing two double bonds in the ring structure and polymers thereof which retain the above characteristic abietyl structure within their molecule, are stabilized by bubbling sulphur dioxide gas through said compounds at temperatures in the range 170-250 DEG  C. at which extensive loss of substituents at the 1-position in the abietyl molecule does not occur.  Specified compounds are rosins and rosin acids, e.g. gum or wood rosins copals; natural or isomerized rosin acids, e.g. abietic, pimaric, sapinic, sapletic, colophonic, pyroabietic acids; hydrogenated and polymerized rosin acids and their aforesaid derivatives, e.g. their salts with sodium, calcium, zinc, lead, cobalt, manganese, aluminium, ammonia, amines, and quaternary base; rosin esters, ethers, and ester-ethers made with alcohols, alkylol-amines and phenols; rosin alcohols and their esters with straight-chain or cyclic acids or with H2SO4, H3PO4, or their organic derivatives.  The abietyl compounds treated may be present in crude turpentine or tall oil.  The treatment may be carried out in solution in hydrocarbons, or chlorinated benzene.  The SO2 treated rosin acids may be afterwards esterified, or converted into a salt or an alcohol or the two reactions may be carried out concurrently.  The products undergo reactions of aromatic compounds, e.g. they may be sulphonated.  The rate of SO2 flow per hour is about 0.5 per cent to 5 per cent based on the weight of resin, the preferred temperatures being 200 DEG  to 230 DEG  C. If decarboxylation is also desired temperatures of 250 DEG  to 350 DEG C. may be used.  Graphs and tables show the variations in iodine number, acid number, colour and melting point of the products with variations of the temperature, time, and amount of sulphur dioxide supplied in the treatment.  The treated products may be purified by fractional distillation, solvent extraction, fractional precipitation, crystallization or by sulfonation.  Examples 1-6 describe the SO2 treatment at 225 DEG  C. of WW wood resin, WW gum rosin, wood rosin sodium soap, crude tall oil, tall oil distillate, and crude turpentine.  Examples 8-10 describe the esterification of the treated rosin with glycerine, diethylene glycol, and cetyl alcohol.  In the latter case the treated rosin is first converted to the acid chloride by treatment with thionyl chloride.  Examples 7 and 11-13 illustrate the formation of soaps and salts by treatment of the stabilized rosin with sodium sulphite, sodium carbonate, lead acetate and calcium carbonate. In example 14 the treated rosin is decarboxylated by heating it with p-toluene sulphonic acid at 290 DEG C.  Further examples show the effect of varying the temperature and the amount of SO2 employed (examples 25-30); the use of stearic acid as solvent (example 31); the fractional distillation and crystallization of the products (examples 32-36); the saponification and sulphurisation of the product (examples 37-40).ALSO:Abietyl compounds in the form of rosin acids, salts, esters, ethers, ester-ethers, and alcohols having either a single double bond or a conjugated system containing two double bonds in the ring structure and polymers thereof which retain the above characteristic abietyl structure within their molecule, are stabilized by bubbling sulphur dioxide gas through said compounds at temperatures in the range 170-250 DEG  C. at which extensive loss of substituents at the 1-position in the abietyl molecule does not occur.  Specified compounds are rosins and rosin acids, e.g. gum or wood rosins copals; natural or isomerized rosin acids, e.g. abietic, pimaric, sapinic, sapletic, colophonic, pyroabietic acids; hydrogenated and polymerized rosin acids and their aforesaid derivatives, e.g. their salts with sodium, calcium, zinc, lead, cobalt, manganese, aluminium, ammonia, amines, and quaternary bases; rosin esters, ethers, and ester-ethers made with alcohols, alkylol-amines and phenols; rosin alcohols and their esters with straight chain or cyclic acids or with H2SO4, H3PO4 or their organic derivatives. The abietyl compounds treated may be present in crude turpentine or tall oil.  The treatment may be carried out in solution in hydrocarbons, or chlorinated benzene.  The SO2 treated rosin acids may be afterwards esterified, or converted into a salt or an alcohol or the two reactions may be carried out concurrently. The products undergo reactions of aromatic compounds, e.g. they may be sulphonated.  The rate of SO2 flow per hour is about 0.5 to 5 per cent based on the weight of resin, the preferred temperatures being 200 DEG  to 230 DEG  C.  If decarboxylation is also desired temperatures of 250 DEG  to 350 DEG  C. may be used. Graphs and tables show the variations in iodine number, acid number, colour and melting point of the products with variations of the temperature, time, and amount of sulphur dioxide supplied in the treatment.  The treated products may be purified by fractional distillation, solvent extraction, fractional precipitation, crystallization or by sulfonation.  Examples 1-6 describe the SO2 treatment at 225 DEG  C. of WW wood rosin, WW gum rosin, wood rosin sodium soap, crude tall oil, tall oil distillate, and crude turpentine.  Examples 8-10 describe the esterification of the treated rosin with glycerine, diethylene glycol, and cetyl alcohol.  In the latter case the treated rosin is first converted to the acid chloride by treatment with thionyl chloride.  Examples 7 and 11-13 illustrate the formation of soaps and salts by treatment of the stabilized rosin with sodium sulphite, sodium carbonate, lead acetate and calcium carbonate.  In example 14 the treated rosin is decarboxylated by heating it with p-toluene sulphonic acid at 290 DEG  C.  Further examples show the effect of varying the temperature and the amount of SO2 employed (examples 25-30); the use of stearic acid as solvent (example 31) the fractional distillation and crystallization of the products (example 32-36) the saponification and sulphurization of the product (examples 37-40).