POLYESTER POLYOLS COMPRISING ISOSORBIDE, ISOIDIDE OR ISOMANNIDE-DERIVED UNITS

Abstract

The present invention relates to polyester polyols comprising units derived from a) at least one component (A) carrying at least one COOH group or a derivative thereof, wherein component (A) comprises (i) at least one compound carrying two COOH groups or derivatives thereof (A1), and b) at least one component (B) carrying at least one OH group and no COOH group, wherein component (B) comprises (ii) at least one compound or oligomer carrying at least three OH groups and no COOH group (B1), (iii) at least one compound carrying two OH groups (B2) selected from the group consisting of

##STR00001##

B2a and B2c, wherein n and m are independently from each other 0 or 1, and R.sup.1 and R.sup.2 are independently selected from the group consisting of H, CH.sub.3 and CH.sub.2CH.sub.3, and (iv) optionally at least one compound, oligomer or polymer carrying two OH groups and no COOH group, which is different from B2 (B3), wherein the molar ratio of the OH groups of components B1 to the sum of OH groups of components B1, B2 and B3 is in the range of from 25 to 90%, and to an organic solvent-based two-component coating composition comprising a) a first component (K1) comprising (i) at least one polyester polyol of the present invention, and (ii) optionally at least one polymer carrying more than one OH group, which is different from the polyester polyol of the present invention, (D), and b) a second component (K2) comprising (i) at least one compound, oligomer or polymer carrying more than one NCO group or blocked NCO group (F), to substrates coated with the coating compositions, and to coating layers on a substrate formed from the coating compositions.

Claims

1-17. (canceled)

18. A polyester polyol comprising units derived from a) at least one component (A) carrying at least one COOH group or a derivative thereof, wherein component (A) comprises (i) at least one compound carrying two COOH groups or derivatives thereof (A1), and b) at least one component (B) carrying at least one OH group and no COOH group, wherein component (B) comprises (ii) at least one compound or oligomer carrying at least three OH groups and no COOH group (B1), (iii) at least one compound carrying two OH groups (B2) selected from the group consisting of ##STR00009## wherein n and m are independently from each other 0 or 1, and R.sup.1 and R.sup.2 are independently selected from the group consisting of H, CH.sub.3 and CH.sub.2CH.sub.3, and (iv) optionally at least one compound, oligomer or polymer carrying two OH groups and no COOH group, which is different from B2 (B3), wherein the molar ratio of the OH groups of components B1 to the sum of OH groups of components B1, B2 and B3 is in the range of 25 to 90%.

19. The polyester polyol of claim 18, wherein compound A1 is at least one aliphatic or alicyclic compound carrying two COOH groups or a derivative thereof

20. The polyester polyol of claim 18, wherein compound or oligomer B1 carries three OH groups and no COOH group.

21. The polyester polyol of claim 18, wherein the compound carrying two OH groups (B2) is a compound of formula ##STR00010## wherein n and m are independently from each other 0 or 1, and R.sup.1 and R.sup.2 are independently selected from the group consisting of H, CH.sub.3 and CH.sub.2CH.sub.3, with the proviso that at least one of R.sup.1 or R.sup.2 is H.

22. The polyester polyol of claim 18, wherein the molar ratio of the OH groups of components B1 to the sum of OH groups of components B1, B2 and B3 is in the range of 50% to 90%.

23. The polyester polyol of claim 22, wherein the molar ratio of the OH groups of components B1 to the sum of OH groups of components B1, B2 and B3 is in the range of from to 85%.

24. The polyester polyol of claim 18, wherein the molar ratio of the sum of OH groups of all components A and B to the sum of COOH groups of all components A is in the range of 1.05/1 to 3/1.

25. The polyester polyol of claim 18, wherein the polyester polyols have a hydroxyl number in the range of 50 to 400 mg KOH/g.

26. The polyester polyol of claim 18, wherein the polyester polyols have an acid number in the range of 1 to 200 mg KOH/g.

27. The polyester polyol of claim 18, wherein the polyester polyols have a number average molecular weight Mn in the range of 400 to 5000 g/mol.

28. The polyester polyols of claim 18, wherein the polyester polyols have a weight average molecular weight Mw in the range of 400 to 15000 g/mol.

29. A solution comprising the polyester polyols of claim 18, and at least one organic solvent.

30. An organic solvent-based two-component coating composition comprising a) a first component (K1) comprising (i) at least one polyester polyol of claim 18, and (ii) optionally at least one polymer carrying more than one OH group, which is different from the polyester polyol of the present invention, (D) and b) a second component (K2) comprising (i) at least one compound, oligomer or polymer carrying more than one NCO group or blocked NCO group (F).

31. The organic solvent-based two-component coating composition of claim 30, wherein the polymer carrying more than one OH group, which is different from the polyester polyol of the present invention, (D) is present and is at least one (meth)acrylic polymer carrying more than one OH group.

32. The organic solvent-based two-component coating composition of claim 30, wherein the first component (K1) and/or the second component (K2) also comprises at least one organic solvent, at least one catalyst, at least one pigment, and at least one additive.

33. A substrate coated with the organic solvent-based two component composition of claim 30.

34. A coating layer on a substrate formed from the organic solvent-based two component composition of claim 30.

Description

EXAMPLES

[0236] Description of Test Methods

[0237] The weight average molecular weight Mw and number average molecular weight Mn were determined using gel permeation chromatography calibrated to a polystyrene standard.

[0238] The glass transition temperature (Tg) was determined using differential scanning calorimetry.

[0239] The hydroxyl number was determined according to DIN53240, 2016.

[0240] The acid number was determined according to DIN53402, 1990.

[0241] The solid content of solutions comprising polyester polyol were measured using a moisture analyzer (Mettler Toledo HB43-S Moisture Analyzer) at 160 C. until constant mass was reached.

[0242] The solid content of white pigmented coating compositions comprising the polyester polyol solutions were calculated based on the measured solid content of the polyester polyol solutions.

[0243] The viscosity was determined using a cone plate viscosimeter set to a shear rate of 100 s.sup.1 at 23 C.

[0244] Cotton wool drying time: The coating composition was applied with a draw down bar on a glass plat yielding a wet film thickness of 150 m. After film application, a frayed cotton wool was swept without pressure across the surface of the coating every 5 to 10 minutes. At the beginning, cotton fibers were sticking to the coating. The time when no fibers remained attached to the coating, is referred to as the cotton wool drying time.

[0245] Pendulum hardness [osc.]: The coating composition was applied with a draw down bar having a gap of 150 m on a 4 mm thick glass plate, which has been cleaned with acetone before, yielding a wet film. The pendulum hardness was measured according to DIN EN ISO 1522:2006 using the Konig pendulum.

Comparative Example 1

[0246] Preparation of a Solution Comprising a Polyester Polyol Comp1 Prepared from HHPA and TMP

[0247] Cyclohexane-1,2-dicarboxylic acid anhydride (mixture of isomers) (HHPA) and 1,1,1-trime-thylolpropane (TMP) were mixed in a molar ratio as indicated in table 1 and slowly heated to 160 C. under a steady stream of nitrogen. When the reaction mixture reached 135 C., an exothermic reaction was observed. The reaction mixture was kept at 160 C. for 30 min, and then heated to 180 C. Water was removed by distillation. The reaction was monitored by the titration of the acid number and cooled down to 80 C. when the desired value was reached. Butyl acetate was added to the melt to yield a solution comprising a polyester polyol comp 1 with a solid content as indicated in table 1. The solid content, the hydroxyl number, the acid number, the glass temperature (Tg) the number average molecular weight (Mn), the weight average molecular weight (Mw) of the polyster polyol comp1 and the viscosity of the solution of the polyster polyol comp 1 were determined according to the methods described in the section above titled Description of test methods and are also shown in table 1.

Comparative Example 2

[0248] Preparation of a Solution Comprising Polyester Polyol Comp2 Prepared from HHPA, CHDM and THEIC

[0249] Cyclohexane-1,2-dicarboxylic acid anhydride (mixture of isomers) (HHPA), 1,4-bis(hydroxymethyl)cyclohexane (CHDM) and 1,3,5-tris(2-hydroxyethyl) isocyanurate (THEIC) were mixed in a molar ratio as indicated in table 1 and slowly heated to 160 C. under a steady stream of nitrogen. When the reaction mixture reached 135 C., an exothermic reaction was observed. The reaction mixture was kept at 160 C. for 30 min, and then heated to 180 C. Water was removed by distillation. The reaction was monitored by the titration of the acid number and cooled down to 80 C. when the desired value was reached. Butyl acetate was added to the melt to yield a solution comprising the polyester polyol comp2 with a solid content as indicated in table 1. The solid content, the hydroxyl number, the acid number, the glass temperature (Tg) the number average molecular weight (Mn) and the weight average molecular weight (Mw) of polyster polyol of polyster polyol comp2 and the viscosity of the solution of polyster polyol comp2 were determined according to the methods described in the section above titled Description of test methods and are also shown in table 1.

Example 1

[0250] Preparation of Solutions Comprising Hyperbranched Polyester Polyols 1a, 1b and 1c Comprising Isosorbide

[0251] Cyclohexane-1,2-dicarboxylic acid anhydride (mixture of isomers) (HHPA), isosorbide and 1,3,5-tris(2-hydroxyethyl) isocyanurate (THEIC) were mixed in a molar ratio as indicated in table 1. 500 ppm of titanium(IV) n-butoxide, based on the weight of the reaction mixture, was added. The reaction mixture was slowly heated to 160 C. under a steady stream of nitrogen. When the reaction mixture reached 135 C., a light exothermic reaction was observed. The reaction mixture was kept at 160 C. for 30 min, and then heated to 180 C. Water was removed by distillation. The reaction was monitored by the titration of the acid number and cooled down to 80 C. when the desired value was reached (51 mg KOH/g for 1a, 121 mg KOH/g for 1b and 53 mg KOH/g for 1c). Butyl acetate was added to the melt to yield a solution comprising the polyester polyol 1a, 1b and 1c, respectively, with a solid content as indicated in table 1. The solid content, the hydroxyl number, the acid number, the glass temperature (Tg) the number average molecular weight (Mn) and the weight average molecular weight (Mw) of polyster polyol 1a, 1b and 1c and the viscosity of the solution of polyster polyol 1a, 1b and 1c, respectively, were determined according to the methods described in the section above titled Description of test methods and are also shown in table 1.

TABLE-US-00001 TABLE 1 polyester polyol monomers comp1 Comp2 1a 1b 1c HHPA 50 47.1 47.1 53.3 53.3 CHDM 17.7 isosorbide 17.7 20.0 20.0 THEIC 35.3 35.3 26.7 26.7 TMP 50 properties Hydroxyl number 285 178 189 149 77 [mg KOH/g] acid number [mg 85 26 51 121 53 KOH/g] Mn [g/mol] 1050 750 530 450 970 Mw [g/mol] 1650 1580 1030 680 3080 Tg [ C.] 9 47.3 41.2 36.6 49.1 solid content [%] 69.1 67.4 64.4 64.1 67.8 Viscosity 3851 5100 4650 1740 7900 [mPa s]

Example 2

[0252] Preparation of a White Pigment Paste

[0253] 20 g Laropal A-8L (a grinding resin, 80% solution of a condensation product of urea and aliphatic aldehyde in 1-methoxy-2-propyl acetate, hydroxyl number: 90 mg KOH/g, available from BASF), 3.0 g 1-methoxy-2-propyl acetate and 3.0 g EFKA PX 4330, a high molecular weight dispersing agent available from BASF, were mixed using a lab stirrer. The speed of the stirrer was slowly increased to 4000 rpm and kept at that speed for 5 minutes. 74.0 g Kronos 2310, a white pigment with a white pigment index 6, was slowly added to the mixture under stirring. The speed of the stirrer was slowly increased to 5000 rpm and kept at that speed for 10 minutes. Then, the mixture was placed in a grinding mill. 150 g glass beads with a diameter in the range from 0.75 to 1 mm were added and the mixture was grinded at a speed of 5500 rpm for 30 minutes. Afterwards, the white pigment paste was separated from the glass beads using compressed air.

Example 3

[0254] Preparation of a white pigmented coating composition comprising the polyester polyols comp1, comp2, 1a, 1b and 1c, respectively, and application of the coating compositions on a glass plate

[0255] 0.647 g of a 1 wt % solution of dibutyltin(IV) dilaurate (catalyst) in butyl acetate was added in a 100 mL glass jar. Then, 0.388 g EFKA PB 2744 (a defoamer available from BASF) was added, followed by 0.516 g EFKA WE 3050 (a levelling agent available from BASF).

[0256] Then, 18 g of of Setalux 1907 BA-75 (a 75 weight % solution of an acrylic polyol with 4.5% OH groups calculated on non-volatiles and available from Allnex in butyl acetate) was combined with the amount of the solution of polyester polyol of comparative example 1, comparative example 2, example 1 and example 2, respectively, comprising the polyester polyol compl, comp2, 1a, 1b and 1c, respectively, containing 4.5 g solids, and the obtained mixture comprising the acrylic polyol and polyester polyol was added to the mixture above comprising catalyst, defoamer and levelling agent.

[0257] 49.10 g of the white pigment paste of example 3 was added to the mixture. The mixture was stored for 16 h. Then, 10 g butyl acetate was added, and the mixture was stirred using a lab stirrer with a 35 mm disc at a speed of 750 rpm for 5 minutes.

[0258] Basonat HI 2000 NG (solvent-free, aliphatic polyisocyanate) at an index of 100 (with respect to the OH groups of Setalux 1907 BA-75, polyester polyol, and Laropal A-8L) was added to the mixture. The mixture was stirred using a lab stirrer with a 35 mm disc at a speed of 750 rpm for 10 minutes. Subsequently, butyl acetate was added in an amount that the viscosity measured with a cone plate viscosimeter corresponds to 200 mPas. After waiting for 10 min, the pigmented coating composition was ready to use.

[0259] After cleaning glass substrates properly with acetone, the pigmented coating compositions were applied with a draw down bar with a wet film thickness of 200 m. The dry film thickness was approximately 60 m.

[0260] The solid content, the cotton wool drying time and the pendulum hardness [osc.] of the white pigmented coating compositions comprising polyester polyols comp1, comp2, 1a, 1b and 1c, respectively, were determined as described above in the section titled Description of Test Methods and are shown in table 2.

TABLE-US-00002 TABLE 2 .sup.1Pendulum Hardness. Pigmented coating composition comprising polyester polyol monomers comp1 Comp2 1a 1b 1c HHPA 50 47.1 47.1 53.3 53.3 CHDM 17.7 isosorbide 17.7 20.0 20.0 THEIC 35.3 35.3 26.7 26.7 TMP 50 properties solid content [%] 76.4 76.9 75.7 75.3 75.7 cotton wool drying 160 90 60 60 50 time [min] PH.sup.1 [osc.] after 1 d at 14 14 13 15 14 RT PH.sup.1 [osc.] after 2 d at 33 29 26 25 28 RT PH.sup.1 [osc.] after 7 d at 38 38 36 30 35 RT PH.sup.1 [osc.] after 7 d at 52 53 50 45 48 RT + 15 h at 60 C.) PH.sup.1 [osc.] after 15 33 35 38 41 37 min at RT + 30 min at 60 C. + 1 d at RT PH.sup.1 [osc.] after 15 60 59 81 65 59 min at RT + 30 min at 60 C. + 6 d at RT PH.sup.1 [osc.] after 15 88 82 95 88 80 min at RT + 30 min at 80 C. + 6 d at RT

[0261] Table 2 shows that inventive white pigmented organic solvent-based two-component coating compositions comprising polyester polyol 1a, 1b and 1c (comprising isosorbide), respectively, show a shorter cotton wool drying time than comparative white pigmented organic solvent-based two-component coating compositions comprising polyester polyol compl (comprising trimethylolpropane instead of isosorbide) or polyester polyol comp2 (comprising 1,4-bis(hydroxymethyl)cyclohexane (CHDM) instead of isosorbide). At the same time the inventive white pigmented organic solvent-based two-component coating compositions comprising polyester polyol 1a, 1b and 1c, respectively, have a comparable solid content and comparable pendulum hardness than the coating composition comprising polyester polyol comp2 or polyester polyol comp1.