Wood preservatives

Abstract

A wood preservative composition and method for preserving wood by contacting wood with said composition comprising a polyurethane polymer, non-aqueous solvents, and a wood preservative active.

Claims

1. A method for preserving wood comprising: contacting wood with a wood preservation composition comprising a) a polyurethane polymer synthesized from i) a polyol comprising >95% p-propylene oxide, ii) an isocyanate, and iii) a capping agent; b) an organic solvent; and c) at least one wood preservative active selected from among halogenated isothiazolone biocides, halogenated carbamate fungicides and azole fungicides; wherein the capping agent is selected from the group consisting of a mono alcohol, a secondary amine, a primary amine with alkyl chain greater than C15 and mixtures thereof; and further wherein the molecular weight of the polyol is greater than or equal to 2700.

2. The method of claim 1 wherein the at least one wood preservative active is 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one.

3. The method of claim 1 wherein the organic solvent comprises diesel.

4. The method of claim 1 wherein the polyol comprises 100% p-propylene oxide.

5. The method of claim 1 wherein the isocyanate is a diisocyanate.

6. A wood preservation composition comprising a) a polyurethane polymer synthesized from i) a polyol comprising >95% p-propylene oxide, ii) an isocyanate, and iii) a capping agent; b) an organic solvent; and c) at least one wood preservative active selected from among halogenated isothiazolone biocides, halogenated carbamate fungicides and azole fungicides; wherein the capping agent is selected from the group consisting of a mono alcohol, a secondary amine, a primary amine with alkyl chain greater than C15 and mixtures thereof; and further wherein the molecular weight of the polyol is greater than or equal to 2700.

7. The composition of claim 6 wherein the at least one wood preservative active is 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one.

8. The composition of claim 6 wherein the organic solvent comprises diesel.

9. The composition of claim 6 wherein the polyol comprises 100% p-propylene oxide.

10. The composition of claim 6 wherein the isocyanate is a diisocyanate.

Description

EXAMPLES

(1) Synthesis of Polyurethane Polymers:

(2) The following polyurethanes were synthesized from a bis hydroxy terminated polypropylene oxide (polyol) and a diisocyanate (IPDI or MDI). 150 mL of anhydrous polypropylene oxide in aromatic 200 (solvent, 10-30 wt % solution), diisocyanate (2 molar equivalents of isocyanates to hydroxyl groups), was charged with 0.003% of a tin catalyst (dibutyltin dilaurate) to the reactor. Polyols of three varying molecular weights were tested: 4000 MW, 2700 MW, and 2000 MW. The reactor was heated to 90? C. with overhead stirring. The reaction mixture was held at 90? C. for 1 h.

(3) The residual isocyanate, in the polyurethane capped examples, is measured using Surface SWYPE? test strips. The reaction product was cooled to room temperature and the capping reagent, mono amine (1 equivalent amine to unreacted isocyanate) was added to cap the remaining isocyanate groups in the reaction mixture. Alternatively, when mono alcohol (1 equivalent hydroxyl to unreacted isocyanate) was used as the capping reagent it was added at 90? C. and reacted for an additional 1 h at 90? C. The reaction is continued at 90? C. until no free isocyanate was observed when tested with SWYPE? test strips. The polymer solids of the PU solution was estimated from the conversion and the amount of reactants used for the reaction. The polymer solids are calculated as the sum of the reactive components in the synthesis of the polymer.

(4) Procedure to Determine Diesel Compatibility:

(5) In a clear, 1 oz vial, 0.1 gram of the polymer (on a 100% polymer solids basis) is diluted with 9.9 grams of diesel fuel (weight/weight) to a 1% solution of the polymer. The sample is maintained at room temperature for 48 hours. After 48 hours, the solution is checked for incompatibility, defined as phase separation, precipitation of the polymer as solids, and/or turbidity.

(6) Calculations of Hansen Solubility Parameters:

(7) Hansen solubility parameters (HSP) for the various polyurethane end cap segments were computed using HSPiP software (Purchased from https://www.hansen-solubility.com/). Predicted HSPs (using the Y-MB method), namely, the HSP for the dispersion (D), polar (P), and hydrogen bonding (H) contributions (all SP in MPa1/2), the total SP (calculated using the predicted HSP), and End cap distance from diesel were computed. According to the HSP theory, the distance between two materials is a measure of the solubility. The smaller the distance the more soluble the fluids are within one another. HSP data for a diesel was obtained from the literature (Batista et al. J. Am. Oil Chem. Soc. V92, 95, 2015).
?.sub.T=?{square root over (?.sub.D.sup.2+?.sub.P.sup.2+?.sub.H.sup.2)}
R.sub.a=?{square root over (4(?.sub.D1?.sub.D2).sup.2+4(?.sub.P1=?.sub.P2).sup.2+4(?.sub.H1??.sub.H2).sup.2)}
?.sub.D1=Dispersive solubility parameter for Diesel=14.51
?.sub.D2=Dispersive solubility parameter for a given end group (?.sub.D)
?.sub.P1=Polar solubility parameter for Diesel=3.18
?.sub.P2=Polar solubility parameter for a given end group (?.sub.P)
?.sub.H1=H-bonding solubility parameter for Diesel=5.97
?.sub.H2=H-bonding solubility parameter for a given end group (?.sub.H)

(8) TABLE-US-00001 TABLE 1 Diesel Compatibility of PU Polymers with 100% p-iPO and IPDI with various cap segments (MW = 2700 to 4000) Diesel compatibility Calculated Hansen Solubility (1 wt. %) Parameters (MPa.sup.1/2) for End Polyol Polyol Cap Segment and End Cap MW = 4000 MW = 2700 End Capping distance from Diesel (Ra) EX-1-22; EX-1-22; Example # Reagent ?.sub.T ?.sub.D ?.sub.P ?.sub.H Ra Comp 1-9 Comp 1-9 EX-1 Methanol 28.4 19.1 16 13.6 17.5 YES YES EX-2 1-Propanol 23.4 17.8 11.5 10 11.3 YES YES EX-3 2-Propanol 22.7 17.5 11.4 8.9 10.6 YES YES EX-4 1-Butanol 22.7 17.5 10.4 10 10.2 YES YES EX-5 2-Butanol 21.8 17.3 9.8 8.9 9.1 YES YES EX-6 Sec-Butanol 21.7 17.2 10.1 8.5 9.1 YES YES EX-7 1-Pentanol 21.9 17.4 9.5 9.2 9.2 YES YES EX-8 1-Hexanol 21.1 17.2 8.9 8.4 8.2 YES YES EX-9 1-octanol 19.8 16.9 7.6 6.9 6.6 YES YES EX-10 Docosanol 17.1 16.2 4.3 3.4 4.4 YES YES EX-11 Propylene glycol 20.9 17 9.2 8 8.1 YES YES butyl ether EX-12 Dimethylamine 26.1 18.3 14.3 11.9 14.7 YES YES EX-13 Diethylamine 23.1 17.3 12.2 9.3 11.1 YES YES EX-14 Di-n-butylamine 20.8 16.9 9.3 7.7 8 YES YES EX-15 Di-isobutylamine 19.7 16.5 8.8 6.1 6.9 YES YES EX-16 Dihexylamine 19.7 16.7 8.1 6.6 6.6 YES YES EX-17 Diheptylamine 19.3 16.6 7.8 6.1 6.2 YES YES EX-18 Dioctylamine 18.6 16.5 6.8 5.4 5.4 YES YES EX-19 Didecylamine 18.3 16.4 6.3 5 5 YES YES Comp.1 Benzylamine 26 20.2 12.4 10.7 15.4 NO NO Comp.2 1-butylamine 25.6 18.1 13.2 12.4 13.9 NO NO Comp.3 1-pentylamine 24.5 17.9 12.2 11.5 12.6 NO NO Comp.4 1-hexylamine 22.7 17.5 10.9 9.6 10.4 NO NO Comp.5 1-octylamine 21.9 17.4 9.9 8.8 9.3 NO NO Comp.6 2-ethylhexylamine 21.7 17.3 9.7 8.8 9 NO NO Comp.7 1-undecylamine 20.5 17.1 8.7 7.3 7.7 NO NO Comp.8 1-dodecylamine 20 17 8.1 6.8 7 NO NO Comp. 9 1-Pentadecylamine 19.3 16.8 7.4 5.9 6.2 NO NO Ex-20 1-Hexadecylamine 18.9 16.7 6.9 5.5 5.8 YES YES Ex-21 1-Heptadecylamine 18.8 16.7 6.7 5.4 5.6 YES YES Ex-22 1-Octadecylamine 18.6 16.6 6.5 5.2 5.4 YES YES

(9) In accordance with the present invention, all mono alcohol, all secondary amine, and primary amine with alkyl chains greater than C15 capping agents were compatible.

(10) TABLE-US-00002 TABLE 2 Diesel Compatibility of PU Polymers with 100% p-iPO and IPDI with various cap segments (MW = 2700 to 4000 Vs MW = 2000) Diesel compatibility (1 wt. %) Calculated Hansen Solubility Polyol Polyol Parameters (MPa.sup.1/2) for End MW = 4000 MW = 2700 Cap Segment and End Cap EX. 1-6; EX. 1-6; Polyol End Capping distance from Diesel (Ra) EX. 12-17; EX. 12-17; MW = 2000 Polymer # Reagent ?.sub.T ?.sub.D ?.sub.P ?.sub.H Ra EX. 20-22 EX. 20-22 Comp. 10-24 EX-1; Methanol 28.4 19.1 16.0 13.6 17.5 YES YES NO Comp 10 EX-2; 1-Propanol 23.4 17.8 11.5 10.0 11.3 YES YES NO Comp. 11 EX-3; 2-Propanol 22.7 17.5 11.4 8.9 10.6 YES YES NO Comp. 12 EX-4; 1-Butanol 22.7 17.5 10.4 10.0 10.2 YES YES NO Comp. 13 EX-5; 2-Butanol 21.8 17.3 9.8 8.9 9.1 YES YES NO Comp 14 EX-6; Sec-Butanol 21.7 17.2 10.1 8.5 9.1 YES YES NO Comp 15 EX-12 Dimethylamine 26.1 18.3 14.3 11.9 14.7 YES YES NO Comp 16 EX-13; Diethylamine 23.1 17.3 12.2 9.3 11.1 YES YES NO Comp 17 EX-14; Di-n-butylamine 20.8 16.9 9.3 7.7 8.0 YES YES NO Comp 18 EX-15; Di-iso-butylamine 19.7 16.5 8.8 6.1 6.9 YES YES NO Comp 19 EX-16; Dihexylamine 19.7 16.7 8.1 6.6 6.6 YES YES NO Comp 20 EX-17; Diheptylamine 19.3 16.6 7.8 6.1 6.2 YES YES NO Comp. 21 Ex-20; 1-Hexadecylamine 18.9 16.7 6.9 5.5 5.8 YES YES NO Comp. 22 Ex-21; 1-Hepatadecylamine 18.6 16.6 6.5 5.2 5.4 YES YES NO Comp. 23 Ex-22; 1-octadecylamine 18.6 16.6 6.5 5.2 5.4 YES YES NO Comp 24

(11) TABLE-US-00003 TABLE 3 Diesel Compatibility of PU Polymers with 100% p-iPO and MDI with various cap segments (MW = 2700 to 4000) Diesel compatibility Calculated Hansen Solubility (1 wt. %) Parameters (MPa.sup.1/2) for End Polyol Polyol Cap Segment and End Cap MW = 4000 MW = 2700 End Capping distance from Diesel (Ra) EX-23-30; EX-23-30; Example # Reagent ?.sub.T ?.sub.D ?.sub.P ?.sub.H Ra Comp 25-27 Comp 25-27 EX-23 Methanol 28.4 19.1 16 13.6 17.5 YES YES EX-24 1-octanol 19.8 16.9 7.6 6.9 6.6 YES YES EX-25 Docosanol 17.1 16.2 4.3 3.4 4.4 YES YES EX-26 Dimethylamine 26.1 18.3 14.3 11.9 14.7 YES YES EX-27 Dihexylamine 19.7 16.7 8.1 6.6 6.6 YES YES EX-28 Didecylamine 18.3 16.4 6.3 5 5 YES YES Comp. 25 1-butylamine 25.6 18.1 13.2 12.4 13.9 NO NO Comp. 26 1-octylamine 21.9 17.4 9.9 8.8 9.3 NO NO Comp. 27 1-Pentadecylamine 19.3 16.8 7.4 5.9 6.2 NO NO Ex-29 1-Hexadecylamine 18.9 16.7 6.9 5.5 5.8 YES YES Ex-30 1-Octadecylamine 18.6 16.6 6.5 5.2 5.4 YES YES

(12) In accordance with the present invention, all mono alcohol, all secondary amine, and primary amine with alkyl chains greater than C15 capping agents were compatible