DK172318B1

DK172318B1 - Process for esterifying colophonium (natural resin) and a polyvalent alcohol in the presence of a catalyst

Info

Publication number: DK172318B1
Application number: DK587086A
Authority: DK
Inventors: Ciro S Lampo; William T Turner
Original assignee: Westvaco Corp
Priority date: 1986-12-05
Filing date: 1986-12-05
Publication date: 1998-03-16
Also published as: DK587086A; DK587086D0

Description

DK 172318 B1DK 172318 B1

Den foreliggende opfindelse angår en fremgangsmåde til fremstilling af estere af kolofonium. Mere specifikt ligger forbedringen ifølge opfindelsen i at reagere kolofonium og en polyvalent alkohol i nærværelse af hypophosphorsyrling 5 (H3P02) og en phenolsulfidforbindelse, som kombineret kataly sator, til reduktion af reaktionstiden til dannelse af kolo-fonium-pentaerythritolestere og til at give en kolofonium-ester med forbedret farve- og oxidationsstabilitet.The present invention relates to a process for the preparation of rosin esters. More specifically, the improvement of the invention lies in reacting rosin and a polyhydric alcohol in the presence of hypophosphoric acid 5 (H3 PO2) and a phenolic sulfide compound, as a combined catalyst, to reduce the reaction time to form rosin-pentaerythritol esters and to give a rosin. ester with improved color and oxidation stability.

Kolofonium er fortrinsvis en blanding af C20-ringkondenserede 10 monocarboxylsyrer typisk såsom levopimarinsyre og abietin-syre, som begge er følsomme over for talrige kemiske omdannelser. De kolofonium-stoffer, som den foreliggende opfindelse har relation til, omfatter kolofoniumgummi, trækolofonium og talloliekolofonium eller kolofoniumsyrerne indeholdt deri, 15 fx abietinsyre, pimarinsyre, sapininsyre etc.The rosin is preferably a mixture of C20 ring-condensed 10 monocarboxylic acids typically such as levopimaric acid and abietic acid, both of which are sensitive to numerous chemical conversions. The rosin substances to which the present invention relates include rosin rubber, rosin rosin and tall oil rosin or rosin acids contained therein, e.g., abietic acid, pimaric acid, sapinic acid etc.

Den naturlige adskillelse og gradvise omdannelse af visse af de hydrofile komponenter af saft og dermed beslægtede plante-væsker fra et træs cambium-lag til i stigende grad hydrofobe faste stoffer er den generiske proces til dannelse af for-20 skellige gummier, harpikser og voksarter. Et typisk eksempel på oleoharpiksmellemproduktet ved denne proces er fyrregummi ("pine gum"), som flyder fra harpiksstammen på træet "southern yellow pine" i det sydøstlige USA, Frankrig og i andre lande. Fyrregummi indeholder ca. 80% (gummi) kolofonium og 25 ca. 20% terpentin.The natural separation and gradual conversion of some of the hydrophilic components of juice and related plant fluids from a tree's cambium layer to increasingly hydrophobic solids is the generic process for forming various gums, resins and waxes. A typical example of the oleo resin intermediate in this process is pine gum ("pine gum"), which flows from the resin stock of the "southern yellow pine" tree in the southeastern United States, France, and other countries. Pine rubber contains approx. 80% (rubber) rosin and approx. 20% turpentine.

Harpiksdannelse ud fra oleoharpiks kan resultere fra enten naturlig fordampning af olie fra et ekstrudat eller langsom opsamling i kanaler i saftved og kerneved. Pinus-stubbe er værdifulde nok til at blive høstet, hakket i spåner og eks-30 traheret med hexan eller højerekogende paraffiner til at give trækolofonium, træterpentin og andre terpenbeslægtede forbindelser ved fraktioneret destillation. Ved kraftpulpnings-processen (dvs. sulfatpulpningsprocessen) til fremstilling af papir behandles fyrretræ med alkali, hvilket giver rå tall- DK 172318 B1 2 olie og rå sulfatterpentin som biprodukter. Fraktionering af den rå tallolie giver talloliekolofonium og fedtsyrer.Resin formation from oleo resin can result from either natural evaporation of oil from an extrudate or slow collection in channels in sapwood and corewood. Pinus stumps are valuable enough to be harvested, chopped in shavings and extracted with hexane or higher-boiling paraffins to provide charcoal, wood turpentine and other terpene-related compounds by fractional distillation. In the kraft pulping process (ie the sulphate pulping process) for making paper, pine is treated with alkali, which gives crude tall oil and crude sulphate turpentine as by-products. Fractionation of the crude tall oil yields tall oil rosin and fatty acids.

Den kemiske omdannelse af kolofoniumgummi, træ- og talloliekolofonium, som har relation til denne opfindelse, er esteri-5 ficering. De nyttige produktkarakteristika, der fås ved kolofoniumesterificering til forskellige anvendelser har ført til udvikling af mange esterificeringsprocedurer, især behandling med polyvalente alkoholer. USA patentskrifterne nr. 2.369.125, 2.590.910 og 2.572.086 beskriver kolofoniumesteri-10 ficering med glycerol og pentaerythritol, blandt andre polyvalente alkoholer, sædvanligvis med et kolofoniumdispropor-tioneringstrin inden.The chemical conversion of rosin, wood and tall oil rosin related to this invention is esterification. The useful product characteristics obtained by rosin esterification for various uses have led to the development of many esterification procedures, especially treatment with polyhydric alcohols. US Patent Nos. 2,369,125, 2,590,910 and 2,572,086 disclose rosin esterification with glycerol and pentaerythritol, among other polyhydric alcohols, usually with a rosin disproportionation step within.

USA patentskrift nr. 3.780.012 beskriver forbehandling af talloliekolofonium med paraformaldehyd efterfulgt af destil-15 lation inden esterificeringsreaktionen for at opnå produkt-farveforbedring. USA patentskrift nr. 3.780.013 beskriver trinvis stigende addition af en phenolsulfidforbindelse under talloliekolofonium-pentaerythritolesterificering. Farven af produktet fra disse procedurer blev påstået at være af kate-20 gorien M på U.S.D.A.-skalaen. De kolofoniumfarvestandarder, hvortil der henvises i nærværende ansøgning, er U.S.D.A.-standarder varierende fra X, som er den lyseste, til D, som er den mørkeste farve. Farveskalaen angives som X, WW, WG, N, Μ, K, I, H, G, F, E og D. På grund af den lyse farve af 25 kolofoniumesterprodukterne fra fremgangsmåden ifølge opfindelsen angiver endvidere, blandt de X-farvede kolofoniumfor-bindelser, betegnelserne X-A, X-B og X-C farver, der er lysere end X-farven, idet X-C er den lyseste farve.U.S. Patent No. 3,780,012 discloses pretreatment of tall oil rosin with paraformaldehyde followed by distillation prior to the esterification reaction to obtain product color enhancement. U.S. Patent No. 3,780,013 discloses step-by-step addition of a phenolic sulfide compound under tall oil rosin-pentaerythritol esterification. The color of the product from these procedures was claimed to be of category M on the U.S.D.A. scale. The rosin color standards referred to in this application are U.S.D.A. standards varying from X, which is the lightest, to D, which is the darkest color. The color scale is indicated as X, WW, WG, N, Μ, K, I, H, G, F, E, and D. Due to the bright color of the rosin ester products of the process of the invention, among the X-colored rosin forms, bonds, the designations XA, XB and XC are colors that are brighter than the X color, with XC being the brightest color.

USA-patentskrift nr. 4.172.070 beskriver anvendelse af aryl-30 sulfonsyre i stedet for de traditionelle basiske esterifi-ceringskatalysatorer såsom calciumoxid med henblik på at reducere tiden for talloliekolofonium-pentaerythritolesteri-ficering til opnåelse af kolofoniumester med forbedret oxygenstabilitet, farve og smeltepunkt. Dette arbejde forvirres 35 imidlertid af den usædvanligt store mængde af anvendt penta- DK 172318 B1 3 erythritol (35% ækvivalent overskud), hvilket i sig selv i mærkbar grad ville forøge hastigheden for faldet i syretal-let. Der blev vundet produkter med ring-og-kugle-smeltepunkter på fra 77°C til 86,5°C. Normale kommercielle pentaery-5 thritolestere af kolofoniumforbindelser har ring-og-kugle-smeltepunkter mellem 95°C og 105°C.U.S. Patent No. 4,172,070 discloses the use of aryl sulfonic acid in place of the traditional basic esterification catalysts such as calcium oxide to reduce the time of tall oil rosin-pentaerythritol esterification to obtain rosin ester with improved oxygen stability, color and melting point. However, this work is confused by the unusually large amount of penta-erythritol used (35% equivalent excess), which in itself would noticeably increase the rate of decrease in acid number. Products with ring-and-ball melting points of 77 ° C to 86.5 ° C were obtained. Normal commercial pentaerythritol esters of rosin compounds have ring-and-ball melting points between 95 ° C and 105 ° C.

Europæisk patentansøgning 0.121.125 omhandler disproportionering af kolofonium med et phenolsulfid og efterfølgende esterificering af det dispropotionerede kolofonium med gly-10 cerol i nærværelse af phosphorsyre og omhandler endvidere samtidig disproportionering og esterificering i nærværelse af phenolsulfidet alene. Reaktionerne udføres ved temperaturer på mellem 180°C og 300°C. Europæisk patentansøgning 0.121.125 nævner intet om samtidig disproportionering og esterificering 15 i nærværelse af både et phenolsulfid og phosphorsyre eller for den sags skyld om esterificering af kolofonium med polyvalent alkohol i samtidig nærværelse af et phenolsulfid og hypophosphorsyrling.European Patent Application 0,121,125 discloses disproportionation of rosin with a phenolic sulfide and subsequent esterification of the disproportionate rosin with glycerol in the presence of phosphoric acid and further discloses simultaneous disproportionation and esterification in the presence of the phenolic sulfide alone. The reactions are carried out at temperatures between 180 ° C and 300 ° C. European Patent Application 0,121,125 makes no mention of simultaneous disproportionation and esterification in the presence of both a phenolic sulfide and phosphoric acid or, for that matter, the esterification of rosin with polyhydric alcohol in the presence of a phenolic sulfide and hypophosphoric acid.

USA patentskrift 4.548.746 beskriver en fremgangsmåde til 20 esterificering af kolofonium med pentaerythritol under anvendelse af hypophosphorsyrling som katalysator for at accelerere esterificeringsreaktionen, og det nævnes, at det er muligt at esterificere talloliekolofonium med pentaerythritol uden mærkbar farvenedbryning. Der nævnes intet om, at slut-25 produkterne har særligt fordelagtige egenskaber med hensyn til Deres farvekvalitet, og hovedparten af eksemplerne på esterificering af talloliekolofonium eller trækolofonier i nærværelse af hypophosphorsyrling giver anledning til en mørkere farve af slutproduktet end af udgangsproduktet.U.S. Patent 4,548,746 discloses a process for esterifying rosin with pentaerythritol using hypophosphoric acid as a catalyst to accelerate the esterification reaction, and it is mentioned that it is possible to esterify tall oil rosin with pentaerythritol without appreciable color degradation. There is no mention that the end-25 products have particularly advantageous properties with regard to your color quality, and most of the examples of esterification of tall oil rosin or wood rosin in the presence of hypophosphoric acid cause a darker color of the final product than of the starting product.

30 USA patentskrift 3.377.334 omhandler en fremgangsmåde til disproportionering af kolofonium, men der nævnes intet om esterificering af kolofonium. Kolofoniet opvarmes i nærværelse af en phenolsulfidforbindelse.30 United States Patent 3,377,334 discloses a method for disproportionation of rosin, but there is no mention of rosin esterification. The rosin is heated in the presence of a phenolic sulfide compound.

DK 172318 B1 4DK 172318 B1 4

Formålet med den foreliggende opfindelse er at tilvejebringe en hidtil ukendt fremgangsmåde til fremstilling af estere af kolofonium. Det er et yderligere formål med opfindelsen at anvende en katalysator, som accelerer kolofoniumesterifi-5 cerings-reaktionshastigheden, og resulterer i en reduceret reaktionstid. Det er et yderligere formål med opfindelsen at tillade en reduktion i mængden af den ved reaktionen anvendte mængde polyvalent alkohol, hvilket resulterer i reducerede omkostninger og højere og mere ønskelige smeltepunkter, dvs.The object of the present invention is to provide a novel process for the production of rosin esters. It is a further object of the invention to use a catalyst which accelerates the rosin esterification reaction rate and results in a reduced reaction time. It is a further object of the invention to allow a reduction in the amount of the polyvalent alcohol used in the reaction, resulting in reduced costs and higher and more desirable melting points, i.e.

10 fra 95°C til 105°C. Det er et særligt formål med opfindelsen at tilvejebringe en fremgangsmåde til fremstilling af estere af kolofonium, som udviser en farve, der er ækvivalent med eller lysere end udgangskolofoniet.10 from 95 ° C to 105 ° C. It is a particular object of the invention to provide a process for the production of rosin esters which exhibits a color equivalent to or lighter than the starting rosin.

Det har overraskende vist sig, at hypophosphorsyrling rea-15 gerer synergistisk med en phenolsulfidforbindelse som en kombineret katalysator til accelerering af kolofoniumesteri-ficerings-reaktionshastigheden. Mere specifikt reagerer en kolofonium med i det mindste en ækvivalent mængde af en polyvalent alkohol, fortrinsvis glycerol eller pentaerythri-20 tol, i nærværelse af fra 0,1% til 2,0% hypophosphorsyrling og fra 0,05 til 1,0% af et phenolsulfid, regnet ud fra vægten af kolofonium, ved en temperatur på fra ca. 180°C til ca. 300°C til dannelse af en kolofoniumester med en farve, der er ækvivalent med eller lysere end udgangskolofoniet.Surprisingly, it has been found that hypophosphoric acid reacts synergistically with a phenolic sulfide compound as a combined catalyst to accelerate the rosin esterification reaction rate. More specifically, a rosin reacts with at least an equivalent amount of a polyhydric alcohol, preferably glycerol or pentaerythritol, in the presence of from 0.1% to 2.0% hypophosphoric acid and from 0.05 to 1.0% of a phenolic sulfide, calculated from the weight of rosin, at a temperature of about 180 ° C to approx. 300 ° C to form a rosin ester of a color equivalent to or lighter than the starting rosin.

25 Hypophosphorsyrling er en stærk reducerende syre, der er nyttig på grund af dens antioxiderende eller farvereducerende egenskaber ved fremstilling af lystfarvede fedtsyretaurater (jfr. USA patentskrift nr. 3.232.968), carboxylsyreestere med poly(oxyalkylen)-forbindelser (britisk patentskrift nr.Hypophosphoric acid is a strong reducing acid useful because of its antioxidant or color reducing properties in the preparation of light colored fatty acid taurates (cf. U.S. Patent No. 3,232,968), carboxylic esters with poly (oxyalkylene) compounds (British Patent No.

30 979.673 og USA patentskrift nr. 3.071.604), acryl- og meth- acrylsyrestere af glycoler (japansk patentskrift nr.30,979,673 and U.S. Patent No. 3,071,604), acrylic and methacrylic acid esters of glycols (Japanese Pat.

73.11084) eller i lystfarvede alkylharpikser (japansk patentskrift nr. 12997) . Endvidere er hypophosphorsyrling blevet anvendt som et talloliebehandlingsmiddel til omdannelse af de 35 deri indeholdte urenheder og farvelegemer til en ikke-destil- DK 172318 B1 5 lerbar form og til at fremme decarboxylering af tilstedeværende kolofoniumsyrer (USA patentskrift nr. 2.441.197).73.11084) or in light-colored alkyl resins (Japanese Patent No. 12997). Furthermore, hypophosphoric acid has been used as a tall oil treating agent to convert the impurities and colorants contained therein into a non-distillable form and to promote decarboxylation of rosin acids (US Pat. No. 2,441,197).

Der er nu tilvejebragt en hidtil ukendt kolofoniumesterifi-ceringsproces, som involverer anvendelse af hypophosphorsyr-5 ling i kombination med en phenolsulfidforbindelse som esteri-ficeringskatalysator.A novel rosin esterification process is now provided which involves the use of hypophosphoric acid in combination with a phenolic sulfide compound as the esterification catalyst.

De kolofoniumgummi-, træ- og talloliekolofoniummaterialer, som den foreliggende opfindelse har relation til, kan udsættes for andre behandlinger før esterificeringen. Fx kan 10 kolofoniummaterialet, ud over den destillationsbehandling, som er antydet i de fraktionerede ekstraktionsprocesser, have været udsat for disproportionering, hydrogenering eller polymerisering eller en kombination af disse og/eller andre behandlinger.The rosin, wood and tall oil rosin materials to which the present invention relates can be subjected to other treatments prior to esterification. For example, in addition to the distillation treatment suggested in the fractionated extraction processes, the rosin material may have been subjected to disproportionation, hydrogenation or polymerization, or a combination of these and / or other treatments.

15 Som polyvalente alkoholer kan der anvendes ethylenglycol, propylenglycol, diethylenglycol, triethylenglycol, tetraethy-lenglycol, trimethylenglycol, glycerol, pentaerythritol, dipentaerythritol, tripentaerythritol, trimethylolethan, trimethylolpropan, mannitol, sorbitol samt kombinationer af 20 de nævnte og andre lignende polyvalente alkoholer. Den ved esterificeringen anvendte mængde alkohol kan variere inden for vide grænser, men i almindelighed vil ikke mere end et omtrent 20%'s overskud i forhold til det ækvivalente kombinerende forhold være nødvendig.As polyhydric alcohols, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, trimethylene glycol, glycerol, pentaerythritol, dipentaerythritol, tripentaerythritol, trimethylolethane, trimethylolpropane, mannitol, and the like, and other combinations may be used. The amount of alcohol used in the esterification may vary within wide limits, but in general no more than about 20% excess of the equivalent combining ratio will be required.

25 I almindelighed foretages esterificeringen ved, at kolofoni-et, et op til 50% ækvivalent overskud af en polyvalent alkohol, fortrinsvis 15-20% ækvivalent overskud, og fra 0,1% til 2,0% hypophoshorsyrling og fra 0,05% til 1,0% phenolsulfid regnet ud fra vægten af kolofoniet indføres i en reaktionsbe-30 holder. Reaktionstemperaturen hæves til fra ca. 180°C til ca. 300°C, fortrinsvis fra ca. 250°C til ca. 280°C i op til 15 timer, indtil kolofoniumsyretallet er reduceret til ca. 15 eller derunder. Der kan anvendes længere reaktionstider, men de yderligere tids- og energiomkostninger opvejer i alminde- DK 172318 B1 6 lighed eventuelle opnåede fordele. Den foretrukne mængde hypophosphorsyrling er fra ca. 0,2% til ca. 0,5% regnet ud fra vægten af kolofoniet, og der ses ikke at fås nogen fordele ved at anvende mængder på 0,5% eller derover af hypo-5 phosphorsyrlingen. Den foretrukne mængde af phenolsulfid er fra ca. 0,2% til ca. 0,5% regnet ud fra vægten af kolofoniet.In general, the esterification is done by the rosin, an up to 50% equivalent excess of a polyhydric alcohol, preferably 15-20% equivalent excess, and from 0.1% to 2.0% hypophosphorous acid and from 0.05% to 1.0% phenolic sulfide calculated from the weight of the rosin is introduced into a reaction vessel. The reaction temperature is raised from approx. 180 ° C to approx. 300 ° C, preferably from ca. 250 ° C to approx. 280 ° C for up to 15 hours until the rosin acid number is reduced to approx. 15 or less. Longer reaction times can be used, but the additional time and energy costs generally outweigh any benefits gained. The preferred amount of hypophosphoric acid is from ca. 0.2% to approx. 0.5% based on the weight of the rosin, and no benefits are seen in using amounts of 0.5% or more of the hypophosphorus acid. The preferred amount of phenolic sulfide is from about 0.2% to approx. 0.5% calculated on the weight of the rosin.

Phenolsulfidet er beskrevet i USA patentskrift nr. 3.780.013. Som anført i nævnte patentskrift kan behandlingsmidlet repræsenteres ved følgende struktur: («0>n Γ(Η0>η Ί <0H>nThe phenolic sulfide is disclosed in U.S. Patent No. 3,780,013. As stated in said patent, the treating agent can be represented by the following structure: («0> n Γ (Η0> η Ί <0H> n

I I II I I

(p1)-sx--(p1)-Sx--fp1) (R)m L <R>m Jp <R>m 10 hvor n er et helt tal fra og med 1 til og med 3, p er et helt tal fra og med 0 til og med 100 og fortrinsvis fra og med 5 til og med 20, og summen af m og n på hver aryl er fra og med 1 til og med 5, x er 1, 2 eller 3, og R er en carbonhydrid-gruppe, fx alkylcycloalkyl og substitueret alkyl, fx C-^g, 15 hvor substituenterne er cycloalkyl, aryl, alkaryl og lignende. R indeholder fortrinsvis fra og med 1 til og med 22 carbonatomer. Foretrukne alkylgrupper er ligekædede sekundære og tertiære alkylgrupper indeholdende op til og med 8 carbonatomer. Foretrukne arylgrupper er dem, der indeholder fra og 20 6 til og med 18 carbonatomer, typisk phenyl, naphthyl og anthracyl. Typiske cycloalkylgrupper indeholder 3-8 carbonatomer i ringen, fx cyclopropyl, cyclopentyl og cyclohexyl.(p1) -sx - (p1) -Sx - fp1) (R) m L <R> m Jp <R> m 10 where n is an integer from 1 up to and including 3, p is an integer numbers from 0 to 100 and preferably from 5 to 20, and the sum of m and n on each aryl is from 1 to 5, x is 1, 2 or 3, and R is a hydrocarbon group, for example, alkylcycloalkyl and substituted alkyl, for example C 1-6, wherein the substituents are cycloalkyl, aryl, alkaryl and the like. Preferably, R contains from 1 to 22 carbon atoms. Preferred alkyl groups are straight-chain secondary and tertiary alkyl groups containing up to 8 carbon atoms. Preferred aryl groups are those containing from and from 6 to 18 carbon atoms, typically phenyl, naphthyl and anthracyl. Typical cycloalkyl groups contain 3-8 carbon atoms in the ring, for example cyclopropyl, cyclopentyl and cyclohexyl.

Esterificeringsreaktionen bør med fordel udføres i nærværelse af en inert atmosfære tilvejebragt ved en nitrogenrensning af 25 reaktionsbeholderen inden tilsætning af reaktanterne og en nitrogenskylning under reaktionen. Eftersom lys farve er en DK 172318 B1 7 ønsket egenskab hos kolofoniumesteren, og farven er følsom over for oxygenpåvirkning, bør en sådan påvirkning minimeres.The esterification reaction should advantageously be carried out in the presence of an inert atmosphere provided by a nitrogen purification of the reaction vessel prior to the addition of the reactants and a nitrogen rinse during the reaction. Since light color is a desired property of the rosin ester and the color is sensitive to oxygen influences, such influence should be minimized.

Eftersom en fordel ved den kombinerede hypophosphorsyrling-og phenolsulfidkatalysator er minimal farvedegradation under 5 esterificeringen, er kolofoniumesterfarven primært også afhængig af udgangskolofoniets farve. Når kolofonium esteri-ficeres, tillader de kombinerede katalysatorer ved fremgangsmåden ifølge opfindelsen fremstilling af en ester med en ækvivalent eller lysere farve end udgangskolofoniet.Since an advantage of the combined hypophosphoric acid and phenolic sulfide catalyst is minimal color degradation during esterification, the rosin ester color is also primarily dependent on the color of the starting rosin. When rosin is esterified, the combined catalysts in the process of the invention allow the production of an ester of an equivalent or lighter color than the starting rosin.

10 I en foretrukken udførelsesform af fremgangsmåden ifølge opfindelsen smeltes kolofoniumudgangsmaterialet i en inert atmosfære i reaktionsbeholderen efterfulgt af tilsætning af 0,2% (regnet ud fra vægten af kolofoniet) hypophosphorsyrling (50% aktiv i vand), 0,5% (regnet ud fra vægten af kolofoniet) 15 af et phenolsulfid og et 15-20% ækvivalent overskud af penta-erythritol. Der opretholdes en meget lav skylning med inert gas såsom nitrogen eller carbondioxid, medens blandingen opvarmes til 250°C under omrøring, hvilken temperatur holdes i ca. 3 timer. Reaktionstemperaturen øges derefter til 275°C, 20 indtil reaktionsproduktets syretal er faldet til 15 eller derunder eller i et tidsrum på ca. 2-12 timer. Efter ca. 5-15 timer fra reaktionens begyndelse erstattes skylningen med inert gas med en skylning med damp efterfulgt af tilsætning af ca. 0,053% fast natriumhydroxid (eller anden basisk for-25 bindelse) regnet ud fra vægten af kolofoniet for at neutralisere hypophosphorsyrlingkatalysatoren, og blandingen afkøles til 220-230°C og skylles med nitrogen for at fjerne al fugt. (Alternativt kan der anvendes en 50% vandig natriumhydroxidopløsning) .In a preferred embodiment of the process of the invention, the rosin starting material is melted in an inert atmosphere in the reaction vessel followed by the addition of 0.2% (by weight of rosin) hypophosphoric acid (50% active in water), 0.5% (calculated from the weight of the rosin) of a phenolic sulfide and a 15-20% equivalent excess of penta-erythritol. A very low flush with inert gas such as nitrogen or carbon dioxide is maintained, while the mixture is heated to 250 ° C with stirring, which temperature is maintained for approx. 3 hours. The reaction temperature is then raised to 275 ° C, 20 until the acid number of the reaction product has dropped to 15 or less or for a period of approx. 2-12 hours. After approx. 5-15 hours from the start of the reaction, the inert gas rinse is replaced by a steam rinse followed by the addition of ca. 0.053% solid sodium hydroxide (or other basic compound) calculated from the weight of the rosin to neutralize the hypophosphoric acid catalyst and the mixture is cooled to 220-230 ° C and rinsed with nitrogen to remove all moisture. (Alternatively, a 50% aqueous sodium hydroxide solution may be used).

30 Nedenstående eksempler tjener til at illustrere den uventede farveforbedring i kolofoniumesterne fremstillet ved fremgangsmåden ifølge opfindelsen samt den reducerede reaktionstid. Delangivelserne er efter vægt, medmindre andet er angivet .The following examples serve to illustrate the unexpected color improvement in the rosin esters prepared by the process of the invention as well as the reduced reaction time. The sub-declarations are by weight, unless otherwise stated.

DK 172318 B1 8 EKSEMPEL 1 I en egnet reaktionsbeholder smeltes 500 dele af en tallolie-kolofonium, der har et U.S.D.A.-farveindex på WW, ved 200°C med et dække af nitrogen. Ved 200°C tilsættes der langsomt 5 pentaerythritol i en mængde på 65 dele. Denne blanding blev opvarmet til 250°C i 3 timer under omrøring, hvorefter temperaturen blev hævet til 275°C og holdt der, indtil reaktionsproduktets syretal var 15. Den totale reaktionstid var 43 timer, og den endelige ester havde et U.S.D.A.-farveindex 10 på I.EXAMPLE 1 In a suitable reaction vessel, 500 parts of a tall oil rosin having a U.S.D.A. color index of WW are melted at 200 ° C with a cover of nitrogen. At 200 ° C, 5 pentaerythritol is slowly added in an amount of 65 parts. This mixture was heated to 250 ° C for 3 hours with stirring, then the temperature was raised to 275 ° C and held there until the reaction product's acid number was 15. The total reaction time was 43 hours and the final ester had a USDA color index of 10 IN.

EKSEMPEL 2EXAMPLE 2

Dette og det følgende eksempel viser fordelene ved at anvende en traditionel kolofoniumesterificeringskatalysator ved reaktionen. Reaktionen blev udført som eksempel 1 med und-15 tagelse af, at der før pentaerythritoltilsætningen blev tilsat 1,076 dele calciumformiat som katalysator ved 200°C.This and the following example show the advantages of using a conventional rosin esterification catalyst in the reaction. The reaction was carried out as Example 1 except that before the pentaerythritol addition, 1,076 parts of calcium formate as catalyst were added at 200 ° C.

Den reaktionstid ved 275°C, der var nødvendig for at opnå et reaktionsproduktsyretal på 15, var kun 6 1/2 time ud af en samlet reaktionstid på 9 1/2 time. Endvidere havde den fær-20 dige ester et U.S.D.A.-farveindex på fra M til K og et ring-og -kugle-smeltepunkt på 100°C.The reaction time at 275 ° C required to obtain a reaction product acid number of 15 was only 6 1/2 hours out of a total reaction time of 9 1/2 hour. Furthermore, the finished ester had a U.S.D.A. color index of from M to K and a ring-and-ball melting point of 100 ° C.

EKSEMPEL 3EXAMPLE 3

Reaktionen blev udført som i eksempel 2 med undtagelse af, at der i stedet for calciumf ormiat blev tilsat 1 del calcium-25 hydroxid som katalysator. Den samlede reaktionstid, der var nødvendig for at opnå et syretal på 15, var 10 timer. Den færdige ester havde et U.S.D.A.-farveindex på I.The reaction was carried out as in Example 2 except that 1 part of calcium-25 hydroxide as catalyst was substituted for calcium formate. The total reaction time needed to obtain an acid number of 15 was 10 hours. The finished ester had a U.S.D.A. color index of I.

Katalysatorerne i eksemplerne 2 og 3 giver således reduceret reaktionstid, men der opnås ingen egentlige fordele i pro-30 duktfarve.Thus, the catalysts in Examples 2 and 3 provide reduced reaction time, but no real benefits in product color are obtained.

EKSEMPEL 4 9 DK 172318 B1EXAMPLE 4 9 DK 172318 B1

For at bestemme de opnåede fordele ved at anvende en arylsul-fonsyre som katalysator til kolofoniumesterificeringen (som beskrevet i USA patentskrift nr. 4.172.070), blev reaktionen 5 udført som i eksempel 1 med undtagelse af, at der, efter at pentaerythritolen var blevet sat til den smeltede kolofonium og blandet grundigt ved 200°C, blev tilsat 1 del paratoluen-sulfonsyre. Den tid, der er nødvendig for at opnå et syretal på 15 eller derunder, var 12 timer. Den færdige ester havde 10 et U.S.D.A.-farveindex på fra WW til WG. Selv om reaktionstiden var reduceret i forhold til ingen katalysator, og produktfarven var bedre end den, der blev opnået med katalysatorerne i eksemplerne 2 og 3, blev der kun set ringe eller ingen farvereduktion (lysning) i forhold til udgangskolofoni-15 et.To determine the benefits obtained by using an arylsulfonic acid as a catalyst for rosin esterification (as described in U.S. Patent No. 4,172,070), reaction 5 was carried out as in Example 1 except that after the pentaerythritol had been added to the molten rosin and mixed thoroughly at 200 ° C, 1 part paratoluene sulfonic acid was added. The time needed to obtain an acid number of 15 or less was 12 hours. The finished ester had a U.S.D.A. color index of from WW to WG. Although the reaction time was reduced relative to no catalyst and the product color was better than that obtained with the catalysts in Examples 2 and 3, little or no color reduction (brightening) was seen relative to the starting colophon.

EKSEMPEL 5EXAMPLE 5

Med henblik på at bestemme, hvorvidt der opnås en fordel ved en katalysatorkombination af en arylsulfonsyre og et phenol-sulfid, blev reaktionen udført som i eksempel 4 med undtagel-20 se af, at der efter tilsætning af paratoluensulfonsyren blev tilsat phenolsulfid (Vultac®2, en amylphenolsulfidpolymer forhandlet af Pennwalt) portionsvis i mængder på hver 0,5 dele ved reaktionens begyndelse, 4 timer efter ved 275°C og endelig 4 timer senere ved 275°C. Den totale reaktionstid, 25 der var nødvendig for at opnå et syretal på under 15, var 10 timer, og den færdige ester havde et U.S.D.A.-farveindex på fra X til WW. Der blev således ikke bemærket nogen signifikant forbedring i forhold til, når hver af katalysatorerne blev anvendt alene.In order to determine whether an advantage is obtained from a catalyst combination of an arylsulfonic acid and a phenolic sulfide, the reaction was carried out as in Example 4 except that after the addition of the paratoluene sulfonic acid, phenolic sulfide was added (Vultac® 2 , an amylphenol sulfide polymer marketed by Pennwalt) in portions in each 0.5 part at the beginning of the reaction, 4 hours after at 275 ° C and finally 4 hours later at 275 ° C. The total reaction time required to obtain an acid number below 15 was 10 hours and the finished ester had a U.S.D.A. color index of from X to WW. Thus, no significant improvement was noted when each of the catalysts was used alone.

DK 172318 B1 10 EKSEMPEL 6Example 17

For at påvise den synergistiske katalytiske og produktfarve-forbedrende virkning af kombinationen af phenolsulfid og hypophosphorsyrling ved kolofoniumesterificering blev reak-5 tionen udført som i eksempel 5 med undtagelse af, at der i stedet for paratoluensulfonsyren blev tilsat 1 del 50% aktiv hypophosphorsyrling. Endvidere blev al phenolsulfidet (1,5 dele), i stedet for trinvis tilsætning, tilsat sammen med de andre reaktanter ved reaktionens begyndelse. Efter reaktion i 10 3 timer ved 250°C blev temperaturen hævet til 275 °C i 4 timer, hvilket gav en slutester med et syretal på under 13 og et U.S.D.A.-farveindex på fra X-B til X-C.To demonstrate the synergistic catalytic and product color enhancing effect of the combination of phenolic sulfide and hypophosphoric acid by rosin esterification, the reaction was carried out as in Example 5 except that 1 part of 50% active hypophosphoric acid was added instead of the paratoluene sulfonic acid. Furthermore, all the phenol sulfide (1.5 parts), instead of incremental addition, was added together with the other reactants at the beginning of the reaction. After reaction for 10 hours at 250 ° C, the temperature was raised to 275 ° C for 4 hours, giving a final ester with an acid number below 13 and a U.S.D.A. color index of from X-B to X-C.

EKSEMPEL 7EXAMPLE 7

For at påvise fordelene ved fremgangsmåden ifølge opfindelsen 15 til esterificering af kolofoniumgummi blev reaktionen udført som i eksempel 6 med undtagelse af, at der som udgangskolofo-niummateriale blev anvendt kolofoniumgummi med et U.S.D.A.-farveindex på WG. Slutesteren havde et syretal på 11 og et U.S.D.A.-farveindex på fra X-A til X-B.In order to demonstrate the advantages of the process of the invention 15 for rosin esterification, the reaction was carried out as in Example 6 except that rosin rubber having a U.S.D.A. color index was used on WG. The final tester had an acid number of 11 and a U.S.D.A. color index of from X-A to X-B.

20 Det er klart, at den mærkbare forbedring i den reaktionstid, der er nødvendig for at opnå det ønskede produktsyretal, og den mærkbare forbedring (dvs. lysning) i produktfarven under anvendelse af katalysatorkombinationen ifølge opfindelsen udviser en uventet og ikke-nærliggende synergistisk kataly-25 tisk virkning til kolofoniumesterificering.It will be appreciated that the appreciable improvement in the reaction time required to obtain the desired product acid number and the appreciable improvement (i.e., brightening) in the product color using the catalyst combination of the invention exhibited an unexpected and unrelated synergistic catalyst. 25 effect on rosin esterification.

Selv om opfindelsen i det foreliggende er blevet beskrevet og illustreret under henvisning til forskellige specifikke materialer, procedurer og eksempler er det klart, at opfindelsen ikke er begrænset til de specifikke materialer, kombi-30 nationer af materialer og procedurer valgt til dette formål.Although the present invention has been described and illustrated with reference to various specific materials, procedures and examples, it is clear that the invention is not limited to the specific materials, combinations of materials and procedures selected for this purpose.

Der kan anvendes talrige variationer af sådanne detaljer, hvilket vil være klart for fagfolk.Numerous variations of such details can be used, as will be apparent to those skilled in the art.

Claims

A process for esterification of rosin with a polyhydric alcohol, characterized in that the rosin and polyhydric alcohol are heated in the presence of a catalytic amount of hypophosphoric acid and a phenolic sulfide compound in an inert environment.

Process according to claim 1, characterized in that the reaction is carried out in an inert environment for from 5 to 15 hours at from 180 ° C to 300 ° C in the presence of from 0.1% to 2.0% hypophosphoric acid and from 0 , 05% to 1.0% of a phenolic sulfide compound, followed by a steam rinse and addition of a basic compound in an amount sufficient to neutralize the hypophosphorous acid.

Process according to claim 1, characterized in that the rosin is esterified with up to 50% equivalent excess polyhydric alcohol at from 250 ° C to 280 ° C.

Method according to any one of claims 1-3, characterized in that the rosin is selected from the class consisting of tall oil rosin, rosin and wood rosin.

Process according to any one of claims 1-3, characterized in that a rosin pretreatment step is preceded by rosin esterification.

Process according to claim 5, characterized in that the pretreated rosin is selected from the class consisting of disproportionate rosin, hydrogenated rosin and polymerized rosin. A process according to any one of claims 1-3, characterized in that the polyhydric alcohol is pentaerythritol in an amount of 15-20% equivalent excess.

8. Improvement in the process of esterification of rosin with a polyhydric alcohol to prepare the corresponding ester, characterized in that the esterification reaction is carried out in an inert environment in the presence of from 0.1% to 2.0% hypophosphoric acid and from 0.05% to 1.0% of a phenolic sulfide compound, calculated from the weight of the rosin, at a temperature of about 180 ° C to approx. 300 ° C for a time sufficient to obtain an ester product acid number of 15 or less, and neutralization of the hypophosphorus acid.

Process according to claim 8, characterized in that the rosin is esterified with 15 up to 50% equivalent excess pentaerythritol in the presence of 0.2% to 0.5% hypophosphoric acid and from 0.2% to 0.5% of a phenol sulfide compound and the reaction is carried out under flushing with an inert gas. A method according to claim 1 for carrying out rosin esterification, which comprises reacting rosin with up to 50% equivalent excess of a polyhydric alcohol, calculated from the equivalent weight of rosin, at a temperature from 180 ° C to 300 ° C, characterized in by reacting the rosin and polyhydric alcohol for a period sufficient to obtain an ester product acid number of 15 or less, in the presence of from 0.1% to 2.0% hypophosphoric acid and from 0.05% to 1, 0% of a phenolic sulfide compound of structure DK 172318 B1 7- Γ? .. 17- (Ryl) Sx fAryl) -Sx - fAryl) <R, "- <*>» _.p <% where n is a integer from 1 to 3, p is an integer from 0 to 100, x is from 1 to 3, and the sum of m and n on each aryl is from 1 to 5, aryl is selected from the class consisting of phenyl, naphthyl and anthracyl, and R is a hydrocarbon radical having from 1 to 22 carbon atoms.