Light color rosin ester compositions and methods of making same

1. A rosin ester composition comprising

a reaction product of one or more rosins, one or more polyhydric alcohols, and optionally one or more monocarboxylic acids, and optionally one or more polycarboxylic acids having from 2 to 54 carbon atoms;

from 5 ppm to 200 ppm of a co-catalyst, and

optionally, a disproportionation catalyst, an esterification catalyst, or combinations thereof;

wherein the co-catalyst has a triplet formation quantum yield (ϕ T ) of greater than 0.5 and a triplet lifetime (τ T ) of greater than 0.5 microseconds.

2. The rosin ester composition of claim 1 , wherein the co-catalyst comprises one or more compounds represented by formula:

wherein n=0, 1 or 2;

X represents oxygen, sulphur, nitrogen, or carbon;

Z 1 , Z 2 , Z 3 , Z 4 , Z 5 , Z 6 , Z 7 and Z 8 are the same or different and each represents carbon or nitrogen;

R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 are the same or different and each is independently selected from the group of hydrogen, an alkyl group, an aryl group, an arylalkyl, an alkenyl group, an arylalkenyl group, an alkynyl group, an arylalkynyl group, a cycloalkyl group, a cycloalkylalkyl group, an alkylene group, a cycloalkylalkylene group, an alkynylene group, a phenyl group, a tolyl group, a naphtyl group, a pyridyl group, a furyl group, an acyl group, a propionyl group, a formyl group, a benzoyl group, a acetoxy group, a halogen, an alkoxy group, an amino group, a benzyl, halogen substituted benzyl group, a alkyl substituted benzyl group, a alkoxy substituted benzyl group, a halogen substituted aryl group, an alkyl substituted aryl group, an alkoxy substituted aryl group, a dialkylamino group, a monoalkylamino group, a monoalkylamido group, a dialkylamido group, a cyano group, a hydroxymethyl group, a hydroxyalkyl group, a trifluoromethyl group, a trifluoromethoxy group, a trifluoromethylthio group, a trifluoromethylsulfonyl group, a nitro group, a carboxyl group, a hydroxyl group, an alkoxyalkyl group, an aryloxyalkyl group, a sulfamoyl group, a dimethylsulfamido group, a sulfhydryl group, an alkylsulfonyl group, an arylsulfonyl group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfanyl group, an arylsulfanyl group, a methoxycarbonyl group, an ethoxycarbonyl group, an isopropoxycarbonyl group, a carbamoyl group, a carbonyl chloride group, a phosphine group, a phosphate group, a phosphodiester group, a phosphonic acid group, an oxiranylalkyl group, a carboxyalkyl group, a glucopyranosyl group, and a glucopyranosyloxy group.

3. The rosin ester composition of claim 1 , wherein the one or more rosins has at least 30 wt. % dehydroabietic acid.

4. The rosin ester composition of claim 1 , wherein the disproportionation catalyst is present in an amount from 0.01 wt. % to 5.0 wt. %, relative to the overall weight of the composition.

5. The rosin ester composition of claim 1 , wherein the composition comprises the esterification catalyst in an amount from 0.01 wt. % to 5.0 wt. %.

6. The rosin ester composition of claim 5 , wherein the esterification catalyst is calcium-bis(((3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl)methyl) -ethylphosphonate)).

7. The rosin ester composition of claim 1 , wherein the disproportionation catalyst is selected from the group of 2,2′thiobisphenols, 3,3′-thiobisphenols, 4,4′-thiobis(resorcinol), 1,1′-thiobis(pyrogallol), 4,4′-thiobis(6-t-butyl-m-cresol), 4,4′-thiobis(6-t-butyl-o-cresol) thiobisnaphthols, 2,2′-thio-bisphenols, 3,3′-thio-bis phenols, palladium, nickel, platinum, iodides, sulfides, poly-t-butylphenoldisulfide, 4,4′thiobis(2-t-butyl-5-methylphenol, nonylphenol disulfide oligomers, amylphenol disulfide polymer, and combinations thereof.

8. The rosin ester composition of claim 1 , wherein the one or more rosins comprise any of a tall oil rosin, a gum rosin, a wood rosin, a disproportionated rosin, a fortified rosin and combinations thereof.

9. The rosin ester composition of claim 8 , wherein the fortified rosin comprises a fortifiying agent selected from the group consisting of fumaric acid, maleic acid, acrylic acid, maleic anhydride, citraconic acid, mesaconic acid, itaconic acid, esters thereof, and combinations thereof.

10. The rosin ester composition of claim 1 , wherein the one or more polyhydric alcohols has an average hydroxyl functionality from 2 to 10.

11. The rosin ester composition of claim 1 , wherein the one or more polyhydric alcohols comprise at least one of glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, neopentylglycol, trimethylene glycol, glycerol, trimethylolpropane, trimethylolethane, pentaerythritol, pentaerythritol technical grade, dipentaerythritol, tripentaerythritol, 1,4-cyclohexanediol, polyethylene glycol, polyglycerol, polyglycerol technical grade, polyglycerol-3, polyglycerol-4, cyclohexane-1,4-dimethanol, tricyclo[5.2.1.0(2.6)]decane-4,8-dimethanol, hydrogenated bisphenol A (4,4′-Isopropylidenedicyclohexanol), mannitol, sorbitol, xylitol, maltitol, and lactitol.

12. The rosin ester composition of claim 1 , wherein the one or more monocarboxylic acids are selected from the group of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, cerotic acid, benzoic acid, cyclopropanecarboxylic acid, cyclopentanecarboxylic acid, cyclohexanecarboxylic acid, linoleic acid, alpha-linolenic acid, elaidic acid, sapienic acid, arachidonic acid, myristoleic acid, palmitoleic acid, oleic acid, myristic acid, isostearic acid, and combinations thereof.

13. The rosin ester composition of claim 1 , wherein the one or more polycarboxylic acids are selected from the group of adipic acid, 3-methyladipic acid, succinic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, rosin dimer, isophthalic acid, terephthalic acid, phthalic acid, TOFA dimer, hydrogenated TOFA dimer, 2-(2-carboxyphenyl) benzoic acid, 2,5-furandicarboxylic acid, camphoric acid, cis-norbornene-endo-2,3-dicarboxylic acid, trimellitic acid, and combinations thereof.

14. The rosin ester composition of claim 1 , wherein the composition has an initial (neat) Gardner color, as determined according to ASTM D1544-04 (2010), of less than 10.

15. The rosin ester composition of claim 1 , wherein the composition has a PAN number of equal to or less than 25.

16. The rosin ester composition of claim 1 , wherein the composition exhibits a change of less than 5.0 Gardner color units when heated to a temperature of 177° C. for a period of 96 hours.

17. An adhesive composition comprising the rosin ester composition of claim 1 .

18. A roadmarking composition comprising the rosin ester composition of claim 1 .

19. A pressure sensitive adhesive composition comprising the rosin ester composition of claim 1 .