IMIDE-CONTAINING POLYESTER

Abstract

The present invention relates to a special process for preparing polyesterols having terminal hydroxyl groups and containing imide groups, to the polyesters per se, and to their use for the preparation of polyurethanes.

Claims

1. A process for preparing a hydroxyl group-terminated polyesterol (A) comprising: in a first process step, preparing an imide group-containing mono- or polycarboxylic acid (B) by reacting (B.1) at least one amino acid having one or more amino groups and one or more acid groups with (B.2) at least one carboxylic anhydride having precisely one anhydride group and no further free acid groups in the presence of (C) at least one diol and/or polyol having a molecular weight of 62 to 1000 g/mol, and, in a second process step, esterifying the reaction mixture obtained in the first process without purification, optionally with addition of further component B.2 and/or further component C and/or (D) at least one further mono- and/or polycarboxylic acid which does not fall under the definition of components (B) and (B.2), under polycondensation conditions, wherein auxiliaries and additives (E) are optionally used in the first process step and/or in the second process step and wherein no further solvent besides component (C) is added in the first process step.

2. The process for preparing a hydroxyl group-terminated polyesterol (A) of claim 1, wherein the first process step is conducted at a temperature of 25 C. to 200 C. and the second process step is conducted at a temperature of 150 to 250 C. and at a reduced pressure of 0.1 to 300 mbar.

3. A hydroxyl group-terminated polyesterol obtained by the process as claimed in claim 1.

4. The process as claimed in claim 1, wherein, in the preparation of the hydroxyl group-terminated polyesterol (A), in addition to components (B.1), (B.2), (C), (D) and (E) a further component (F) is used which comprises diols and polyols which do not fall under the definition of component (C), and wherein the proportion of components (B.1), (B.2), (C), (D) and (E) is 80 percent by weight, based on the total amount of all components used.

5. The process as claimed in claim 1, wherein in the preparation of the hydroxyl group-terminated polyesterol (A) exclusively the components (B.1), (B.2), (C), (D) and (E) are used.

6. The process as claimed in claim 1, wherein in the reaction of components (B.1) and (B.2), the molar ratio of amino groups from the at least one amino acid (B.1) to anhydride groups from the at least one carboxylic anhydride (B.2) is in the range from 1.5:1 to 1:1.5.

7. The process as claimed in claim 1, wherein the at least one amino acid (B.1) comprises monoaminomonocarboxylic acid, monoaminodicarboxylic acid, diaminomonocarboxylic acid or diaminodicarboxylic acid.

8. The process as claimed in claim 1, wherein the at least one amino acid (B.1) comprises anthranilic acid (o-aminobenzoic acid), m-aminobenzoic acid, p-aminobenzoic acid, alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, serine, threonine, tryptophan, tyrosine, valine, ornithine, 3-aminopropionic acid, 2-aminobutyric acid, 4-aminobutyric acid, 6-aminocaproic acid, 2-amino-2-methylpropionic acid, 11-aminoundecanoic acid, or homoserine.

9. The process as claimed in claim 1, wherein the at least one carboxylic anhydride (B.2) comprises phthalic anhydride, tetrachlorophthalic anhydride, 3-chlorophthalic anhydride, maleic anhydride, citraconic anhydride, itaconic anhydride, succinic anhydride, 1,8-naphthalic anhydride, or a derivative of any of the foregoing anhydrides.

10. The process as claimed in claim 1, wherein component (C) comprises ethylene glycol, propane-1,2-diol, propane-1,3-diol, butane-1,4-diol, 2-methylpropane-1,3-diol, pentane-1,5-diol, neopentyl glycol, hexane-1,6-diol, 3-methylpentane-1,5-diol, butane-2,3-diol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, glycerol, 1,1,1-trimethylolpropane, pentaerythritol, castor oil, an oligomer of 1,4-butylene glycol, or a polyether polyol.

11. The process as claimed in claim 1, wherein the at least one mono- and/or polycarboxylic acid (D) comprises oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassylic acid, tetradecanedioic acid, thapsic acid, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, citraconic acid, mesaconic acid, oleic acid, ricinoleic acid or furandicarboxylic acid.

12. The process as claimed in claim 1, wherein the hydroxyl group-terminated polyesterol (A) has an OH number of 20 to 500 mg KOH/g and a number-average functionality of 1.4 to 3.5.

13. The process as claimed in claim 1, wherein at least one of the components (B.1), (B.2), (C), (D), (E) and (F) is bio-based.

14. A polyurethane prepared from the hydroxyl group-terminated polyesterol (A) as claimed in claim 3.

15. The hydroxyl group-terminated polyesterol of claim 3, wherein the hydroxyl group-terminated polyesterol has a melting point of <23 C.

16. The hydroxyl group-terminated polyesterol of claim 15, wherein the hydroxyl group-terminated polyesterol has a melting point of 20 C.

17. The polyurethane of claim 14, wherein the polyurethane is a polyurethane foam.

Description

EXAMPLES

[0152] 1. Methods and Materials

[0153] 1.1 Raw Materials Used:

TABLE-US-00001 Trimellitic anhydride (Fluka) Anthranilic acid (Sigma-Aldrich) Acetic acid (Fisher Scientific) Glutaric acid, technical grade (Lanxess AG) Adipic acid (BASF) Phthalic anhydride (My-ChemGmbH) Diethylene glycol (Sigma-Aldrich) Ethylene glycol (Ineos) DL-Glutamic acid (Sigma-Aldrich) DL-Aspartic acid (abcr) DL-Lysine (Sigma-Aldrich) SnCl.sub.22H.sub.2O (Sigma-Aldrich) Glycerol (Sigma-Aldrich) 3-Amino-1-propanol (Acros-Organics) Diglycol terephthalate (Sigma-Aldrich) L 2830: Desmophen L 2830 (Covestro AG), aliphatic polyether polyol having OH number of 28 mg KOH/g, a molar mass of 4000 Da and approx. 90 mol % of primary OH end groups and a viscosity of 860 mPas at 25 C. TCPP Levagard PP (Lanxess AG), trischloroisopropyl phosphate B 8433 Tegostab B844 (Evonik Industries AG), silicone stabilizer B 8325 Tegostab B8325 (Evonik Industries AG), silicone stabilizer DB Desmorapid DB (Covestro AG), activator for the production of rigid polyurethane foams 1792 Desmorapid 1792 (Covestro AG), preparation containing diethylene glycol and potassium acetate; trimerization catalyst A30 Niax* Catalyst A-30 (Momentive Performance Materials Inc.), tertiary amine. Catalyst for the water reaction 117 Addocat 117 (Lanxess AG), tertiary amine Catalyst for the urethane reaction Water deionized water n-pentane (Azelis) 44V70L Desmodur 44V70 L (Covestro AG), MDI isocyanate having an NCO content of 30% to 32% by weight T80 Desmodur T80 (Covestro AG), TDI isocyanate having an NCO content of at least 48% by weight T65N Desmodur T65N (Covestro AG), TDI isocyanate having an NCO content of at least 48% by weight

[0154] 1.2 Methods Used

[0155] The analyses were conducted as follows:

[0156] Viscosity:

[0157] MCR 51 rheometer from Anton Paar in accordance with DIN 53019 using a CP 50-1 measuring cone, diameter 50 mm, angle 1 at shear rates of 25, 100, 200 and 500 s.sup.1. The inventive and non-inventive polyester polyols exhibit viscosity values that are independent of the shear rate. [0158] Hydroxyl number: determined according to DIN 53240-1 (method without catalyst, June 2013). [0159] Acid number: determined according to DIN 51639-1 (November 2014). [0160] Amine number: determined according to DIN EN ISO 2114 (June 2002). [0161] Apparent density: determined according to DIN EN ISO 845 (October 2009). [0162] Flammability characteristics: determined for rigid foams according to DIN 4102-1 (May 1998). determined for flexible foams according to DIN 75200 (September 1980). [0163] Compressive strength rigid foam: compressive stress determined at 10% compression according to DIN EN ISO 844 (November 2014). [0164] Compressive strength flexible foam: compressive stress determined at 40% compression according to DIN EN ISO 3386-1 (October 2015). [0165] Open-cell content: determined according to DIN EN ISO 4590 (December 2016, method 1) with AccuPyc 1330. [0166] Dimensional stability: determined according to DIN ISO 2796 (January 1986) [0167] Melting point: It is determined whether the melting point of the polyesterols is below room temperature. To this end, the polyesterol is stored at room temperature (23 C.) for at least 4 weeks after preparation and inspected visually to determine whether the polyol remains homogeneous and in the liquid state of matter. Polyesterols that crystallize, form solids or become cloudy during this storage are discarded.

[0168] 2. Polyester Synthesis

[0169] 2.1 One-Pot Synthesis Trimellitic Anhydride/Ethylene Glycol/Glycerol/Aminopropanol/Diglycol Terephthalate (Non-Inventive, Comparative Example According to FR1445078A)

[0170] A 2 l four-neck round-bottomed flask equipped with mechanical stirrer, heating mantle, bottom thermometer, nitrogen gas connection, diaphragm pump vacuum connection and a 40 cm filler column with attached column head and jacketed coil condenser was initially charged with 300 g of ethylene glycol (4.83 mol), 46 g of glycerol (0.50 ml), 75 g of 3-amino-1-propanol (1.00 mol) while passing nitrogen through. The mixture was heated to 50 C. and 192 g of trimellitic anhydride (1.00 mol) were added. The mixture was heated to 140 C. for 80 min in order to convert amine and anhydride to the imide. The reaction mixture was cooled to 120 C. and 127 g of diglycol terephthalate (1.00 mol) and the catalyst (14 mg of SnCl.sub.2.2H.sub.2O) were added. The reaction mixture was heated to a bottom temperature of 200 C. and the pressure was lowered in steps over 6 h to approx. 100 mbar, in the course of which 298 g of distillate was collected. The mixture was stirred at a bottom temperature of 220 C. and 60 mbar of pressure for a further 4 h, in the course of which a further 30 g of distillate was collected.

[0171] The product obtained was so highly viscous at room temperature (>100 000 mPa*s at 25 C.) that further processing and use for the production of polyurethane foams was impossible.

[0172] 2.2 One-Pot Synthesis Anthranilic Acid/Trimellitic Anhydride/Glutaric Acid (Non-Inventive)

[0173] A 2 l four-neck round-bottomed flask equipped with mechanical stirrer, heating mantle, bottom thermometer, nitrogen gas connection, diaphragm pump vacuum connection and a 40 cm filler column with attached column head and jacketed coil condenser was initially charged with 349 g of diethylene glycol (3.29 mol) while passing nitrogen through. To this were added 192 g of trimellitic anhydride (1.00 mol) and 137 g of anthranilic acid (1.00 mol) and the reaction mixture was stirred at a bottom temperature of 150 C. for 4 hours. Technical-grade glutaric acid (134 g, 1.00 mol) was added and the reaction mixture was heated to a bottom temperature of 200 C. over 2 hours, in the course of which water was distilled off. 15 mg of SnCl.sub.2.2H.sub.2O were added and the mixture was stirred under reduced pressure at a bottom temperature of 210 C. for 43 hours. 45 g of diethylene glycol (0.42 mol) were added and the mixture was stirred under reduced pressure at a bottom temperature of 200 C. for a further 5 hours. After cooling, the following properties of the polyester were determined: [0174] Hydroxyl number (mg KOH/g): 198 [0175] Acid number (mg KOH/g): 1.2 [0176] Viscosity (mPa*s at 25 C.): n.d./>50 000 [0177] Viscosity (mPa*s at 50 C.): 4050

[0178] 2.3 One-Pot Synthesis Anthranilic Acid/Phthalic Anhydride/Adipic Acid (Inventive Process)

[0179] A 4 l four-neck round-bottomed flask equipped with mechanical stirrer, heating mantle, bottom thermometer, nitrogen gas connection, diaphragm pump vacuum connection and a 40 cm filler column with attached column head and jacketed coil condenser was initially charged with 849 g of diethylene glycol (8.00 mol) while passing nitrogen through. To this were added 296 g of phthalic anhydride (2.00 mol) and 274 g of anthranilic acid (2.00 mol) and the reaction mixture was stirred at a bottom temperature of 150 C. for 3 hours. After cooling to a bottom temperature of 110 C., adipic acid (587 g, 4.02 mol) was added and the reaction mixture was heated to a bottom temperature of 200 C. over 2 hours, in the course of which water was distilled off. 36 mg of SnCl.sub.2.2H.sub.2O were added and the mixture was stirred under reduced pressure at a bottom temperature of 200 to 210 C. for 66 hours. After cooling, the following properties of the polyester were determined: [0180] Hydroxyl number (mg KOH/g): 177 [0181] Acid number (mg KOH/g): 2.0 [0182] Viscosity (mPa*s at 25 C.): 2330

[0183] 2.4 One-Pot Synthesis Aspartic Acid/Phthalic Anhydride/Adipic Acid (Inventive)

[0184] A 2 l four-neck round-bottomed flask equipped with mechanical stirrer, heating mantle, bottom thermometer, nitrogen gas connection, diaphragm pump vacuum connection and a 40 cm filler column with attached column head and jacketed coil condenser was initially charged with 497 g of diethylene glycol (4.68 mol) while passing nitrogen through. To this were added 148 g of phthalic anhydride (1.00 mol) and 133 g of aspartic acid (1.00 mol) and the reaction mixture was stirred at a bottom temperature of 150 C. for 4.5 hours. After cooling to a bottom temperature of 120 C., adipic acid (292 g, 2.00 mol) was added and the reaction mixture was heated to a bottom temperature of 200 C. over 1.5 hours, in the course of which water was distilled off. 19 mg of SnCl.sub.2.2H.sub.2O were added and the mixture was stirred under reduced pressure at a bottom temperature of 200 C. for 19 hours. After cooling, the following properties of the polyester were determined: [0185] Hydroxyl number (mg KOH/g): 180 [0186] Acid number (mg KOH/g): 2.0 [0187] Viscosity (mPa*s at 25 C.): 4600

[0188] 2.5 One-Pot Synthesis Glutamic Acid/Phthalic Anhydride/Adipic Acid (Inventive Process)

[0189] A 2 l four-neck round-bottomed flask equipped with mechanical stirrer, heating mantle, bottom thermometer, nitrogen gas connection, diaphragm pump vacuum connection and a 40 cm filler column with attached column head and jacketed coil condenser was initially charged with 500 g of diethylene glycol (4.71 mol) while passing nitrogen through. To this were added 148 g of phthalic anhydride (1.00 mol) and 147 g of glutamic acid (1.00 mol) and the reaction mixture was stirred at a bottom temperature of 150 C. for 2.5 hours. After cooling to a bottom temperature of 120 C., adipic acid (292 g, 2.00 mol) was added and the reaction mixture was heated to a bottom temperature of 200 C. over 2 hours, in the course of which water was distilled off. 19 mg of SnCl.sub.2.2H.sub.2O were added and the mixture was stirred under reduced pressure at a bottom temperature of 200 C. for 25 hours. 47 g of diethylene glycol (0.44 mol) were added and the mixture was stirred under reduced pressure at a bottom temperature of 200 C. for a further 15 hours. After cooling, the following properties of the polyester were determined: [0190] Hydroxyl number (mg KOH/g): 202 [0191] Acid number (mg KOH/g): 0.8 [0192] Viscosity (mPa*s at 25 C.): 2350

[0193] 2.6 One-Pot Synthesis Glutamic Acid/Phthalic Anhydride (Inventive Process)

[0194] A 2 l four-neck round-bottomed flask equipped with mechanical stirrer, heating mantle, bottom thermometer, nitrogen gas connection, diaphragm pump vacuum connection and a 40 cm filler column with attached column head and jacketed coil condenser was initially charged with 502 g of diethylene glycol (4.73 mol) while passing nitrogen through. To this were added 305 g of phthalic anhydride (2.06 mol) and 304 g of glutamic acid (2.07 mol) and the reaction mixture was stirred at a bottom temperature of 150 C. for 2.5 hours. The reaction mixture was heated to a bottom temperature of 210 C. over 2 hours, in the course of which water was distilled off. 20 mg of SnCl.sub.2.2H.sub.2O were added and the mixture was stirred under reduced pressure at a bottom temperature of 180-210 C. for 2 hours. 98 g of diethylene glycol (0.92 mol) were added and the mixture was stirred under reduced pressure at a bottom temperature of 200-210 C. for a further 11 hours. After cooling, the following properties of the polyester were determined: [0195] Hydroxyl number (mg KOH/g): 297 [0196] Acid number (mg KOH/g): 0.8 [0197] Viscosity (mPa*s at 25 C.): 6500

[0198] 2.7 One-Pot Synthesis Lysine/Phthalic Anhydride/Glutaric Acid (Inventive Process)

[0199] A 2 l four-neck round-bottomed flask equipped with mechanical stirrer, heating mantle, bottom thermometer, nitrogen gas connection, diaphragm pump vacuum connection and a 40 cm filler column with attached column head and jacketed coil condenser was initially charged with 400 g of diethylene glycol (3.77 mol) while passing nitrogen through. To this were added 355 g of phthalic anhydride (2.40 mol) and 176 g of lysine (1.20 mol) and the reaction mixture was stirred at a bottom temperature of 150 C. for 2.5 hours. Technical-grade glutaric acid (178 g, 1.33 mol) was added and the reaction mixture was heated to a bottom temperature of 200 C. over 2 hours, in the course of which water was distilled off. 20 mg of SnCl.sub.2.2H.sub.2O were added and the mixture was stirred under reduced pressure at a bottom temperature of 200 C. for 16 hours. After cooling, the following properties of the polyester were determined: [0200] Hydroxyl number (mg KOH/g): 182 [0201] Acid number (mg KOH/g): 0.5 [0202] Viscosity (mPa*s at 25 C.): 17000

[0203] 3. Rigid Polyurethane Foams

[0204] Rigid polyurethane foams were produced from the above-described polyesterols having an OH number of 150 to 250 according to the following general method. All parts are parts by weight:

TABLE-US-00002 L2830 12 parts Polyester (OH number 150-250) 73 parts TCPP 15 parts B 8443 3 parts Water 0.8 parts DB 1.7 parts 1792 2.8 parts n-Pentane approx. 13.4 parts 44V70L approx. 200 parts

[0205] The exact amount of n-pentane is calculated according to the desired apparent density of the foam. The exact amount of the isocyanate V70L is calculated so that an index (100*molar ratio of NCO groups to NCO-reactive groups) of 350 is achieved.

[0206] The polyols, stabilizers, water, flame retardants and catalysts are stirred for 60 s using a Pendraulik stirrer at 1000 rpm. n-Pentane is added and the mixture is homogenized at 500-1000 rpm. The isocyanate is added and the mixture is stirred for 10 s at 4200 rpm. The mixture is poured into a paper mold and allowed to react to completion. After storage at room temperature overnight, the rigid foam is sawed up and analyzed.

[0207] The comparison standard polyester was prepared from glutaric acid and ethylene glycol (OH number 216, viscosity at 25 C. 1980 mPas).

TABLE-US-00003 Polyester Standard 2.3 2.4 2.5 2.6 2.7 Apparent density 40 41 41 41 42 42 [g/l] Fire test [cm] 10 12 13 11 12 10 Compressive stress 345; 153 364; 164 378; 155 402; 151 424; 169 356; 220 at 10% compression, parallel; transverse [kPa] Open-cell content 9.3 6.7 6.6 7.8 8 7.3 [%] Dimensional 0.1; 0.3; 0.2 0.2; 0.2; 0.1 0.8; 0.0; 0.1 0.8; 0.1; 0.1 0.2; 0.4; 0.5 0.3; 0.4; 0.3 stability 22 C. [%] Dimensional 0.5; 0.4; 0.7 0.7; 0.3; 0.3 1.1; 0.5; 0.6 0.6; 0.4; 0.4 1.2; 0.5; 0.1 0.3; 0.3; 0.5 stability 100 C. [%]