PU COMPOSITE RESINS

Abstract

Disclosed herein is a fiber composite material including: (a) a polyurethane obtained reaction of at least the components: (i) a polyisocyanate composition; and (ii) a polyol composition including at least 15% by weight of an at least trifunctional alcohol (ii.1), which exhibits at least two primary hydroxyl groups (ii.1); and (b) fibers which are at least partially embedded in the compact polyurethane.

Further disclosed herein are a process for producing a fiber composite material, a fiber composite material obtained by this process, and a method of using the fiber composite material for producing a pipe, in particular a conical pipe, a pipe connector, a pressure vessel, a storage tank, an insulator, a mast, a bar, a roller, a torsion shaft, a profile, a piece of sports equipment, a molded part, a cover, an automotive exterior part, a rope, a cable, an isogrid structure or a semi-finished textile product.

Claims

1. A fiber composite material comprising the following components: a) a polyurethane obtained by reaction of at least the components: i) a polyisocyanate composition; and ii) a polyol composition comprising at least 15% by weight of an at least trifunctional alcohol (ii.1), which exhibits at least two primary hydroxyl groups, and less than 10% by weight of polyols which exhibit an end group based on propylene oxide and/or butylene oxide; and b) fibers which are at least partially embedded in the compact polyurethane; wherein polyisocyanate composition (i) and polyol composition (ii) are used in such a ratio that the isocyanate index is between 99 and 400.

2. The fiber composite material according to claim 1, comprising the following components: a) a polyurethane obtained by reaction of at least the components: i) a polyisocyanate composition; and ii) a polyol composition comprising at least 15% by weight of an ethoxylated polyetherol (ii.1); and b) fibers which are at least partially embedded in the compact polyurethane.

3. The fiber composite material according to claim 2, wherein the ethoxylated polyether polyol (ii.1) is obtained by reaction of: ii.1.1) a polyol initiator with a functionality of 3 to 6, with ii.1.2) ethylene oxide, in the presence of an alkoxylation catalyst (ii.1.3); and ii.1.4) optionally further auxiliaries and/or additives.

4. The fiber composite material according to claim 2, wherein the ethoxylated polyether polyol (ii.1) exhibits no end groups based on propylene oxide and/or end groups based on butylene oxide.

5. The fiber composite material according to claim 2, wherein the polyol initiator (ii.1.1) of the ethoxylated polyether polyol (ii.1) comprises a triol with a functionality of 3 ##STR00009##

6. The fiber composite material according to claim 2, wherein the ethoxylated polyether polyol (ii.1) is produced only by the reaction of a polyol initiator (ii.1.1.) and ethylene oxide (ii.1.2), and no further alkylene oxide is used, and/or wherein the ethoxylated polyether polyol (ii.1) is produced only by the reaction of a polyol initiator (ii.1.1.) and ethylene oxide (ii.1.2), and no further initiator, is used.

7. The fiber composite material according to claim 2, wherein the ethoxylated polyether polyol (ii.1) is based on a triol exhibiting the formula (II): ##STR00010## wherein l, m, n and o are each independently of one another an integer from the range from 1 to 6; p, q and r are each independently of one another zero or an integer from the range from 1 to 6; and X.sup.1, X.sup.2 and X.sup.3 are each a —CH.sub.2—CH.sub.2—O— group.

8. The fiber composite material according to claim 1, wherein the polyol composition (ii) comprises no polyols which exhibit a propylene oxide end group or butylene oxide end group, and/or wherein the polyol composition (ii) comprises less than 10% by weight of polyols which exhibit a propylene oxide and/or butylene oxide group.

9. The fiber composite material according to claim 1, wherein the polyol composition (ii) comprises no polyols which exhibit a propylene oxide or butylene oxide group and/or wherein the polyol composition (ii) comprises no polyols based on propylene oxide and/or butylene oxide.

10. A process for the production of a fiber composite material according to claim 1, comprising the stages: A) providing a polyisocyanate composition (i); B) providing a polyol composition (ii) comprising at least 15% by weight of an at least trifunctional alcohol (ii.1), which exhibits at least two primary hydroxyl groups, and less than 10% by weight of polyols which exhibit an end group based on propylene oxide and/or butylene oxide; C) mixing polyisocyanate composition (i) and polyol composition (ii) to obtain a polyurethane reaction mixture (a′); and D) reacting the polyurethane reaction mixture (a′) in the presence of fibers (b) to yield a polyurethane (a), the fibers (b) being at least partially embedded in the polyurethane reaction mixture (a′) or in the polyurethane (a), to obtain a fiber composite material; wherein polyisocyanate composition (i) and polyol composition (ii) are used in such a ratio that the isocyanate index is between 99 and 400.

11. The process for the production of a fiber composite material according to claim 10, comprising the stages: A) providing a polyisocyanate composition (i); B) providing a polyol composition (ii) comprising at least 15% by weight of an ethoxylated polyether polyol (ii.1) and less than 10% by weight of polyols which exhibit an end group based on propylene oxide and/or butylene oxide; C) mixing polyisocyanate composition (i) and polyol composition (ii) to obtain a polyurethane reaction mixture (a′); and D) reacting the polyurethane reaction mixture (a′) in the presence of fibers (b) to yield a polyurethane (a), the fibers (b) being at least partially embedded in the polyurethane reaction mixture (a′) or in the polyurethane (a), to obtain the fiber composite material.

12. The process for the production of a fiber composite material according to claim 10 for the production of fibers or textiles preimpregnated with polyurethane (polyurethane prepregs), comprising mixing the polyisocyanate composition (i) and the polyol composition (ii), bringing them into contact with oriented fibers (b), and subsequently partially curing them.

13. The process for the production of a fiber composite material according to claim 10 for the production of fibers or textiles preimpregnated with polyurethane, comprising mixing the polyisocyanate composition (i) and the polyol composition (ii), polymerizing them at a temperature below 80° C., and subsequently bringing them into contact with oriented fibers (b).

14. A fiber composite material obtained by the process according to claim 10.

15. A method of using the fiber composite material according to claim 1, the method comprising using the fiber composite material for the production of a pipe, a conical pipe, a pipe connector, a pressure vessel, a storage tank, an insulator, a mast, a bar, a roller, a torsion shaft, a profile, a piece of sports equipment, a molded part, a cover, an automotive exterior part, a rope, a cable, an isogrid structure or a semi-finished textile product.

16. The fiber composite material according to claim 2, wherein the ethoxylated polyether polyol (ii.1) is obtained by reaction of: ii.1.1) a polyol initiator with a functionality of 3 or 4, with ii.1.2) ethylene oxide, in the presence of an alkoxylation catalyst (ii.1.3); and ii.1.4) optionally further auxiliaries and/or additives.

17. The fiber composite material according to claim 2, wherein the ethoxylated polyether polyol (ii.1) exhibits exclusively end groups based on ethylene oxide.

18. The fiber composite material according to claim 2, wherein the ethoxylated polyether polyol (ii.1) exhibits exclusively groups based on ethylene oxide and comprises no groups based on propylene oxide and/or groups based on butylene oxide.

19. The fiber composite material according to claim 2, wherein the polyol initiator (ii.1.1) of the ethoxylated polyether polyol (ii.1) comprises a triol of the formula (I): ##STR00011## wherein l, m, n, and o are each independently an integer from the range from 1 to 6.

20. The fiber composite material according to claim 7, wherein l, m, n, and o are all 1.

Description

EXAMPLES

[0266] 1. Chemicals

TABLE-US-00001 Abbreviation Chemical description Polyol 1 Propoxylated glycerol (glycerol-PO) OHN 805 mg KOH/g, viscosity 1275 mPa .Math. s [25° C], Polyol 2 Castor oil Polyol 3 Branched polyether/polyester, not containing EO, OHN 170 mg KOH/g, viscosity 3500 mPa .Math. s [25° C.] Polyol 4 Trimethylolpropane (TMP)-initiated ethoxylated polyol with an OH number (OHN) of 935 mg KOH/g, prepared with KOH as catalyst for the ethoxylation Polyol 5 Propoxylated propylene glycol, OHN 248 mg KOH/g, viscosity 75 mPa .Math. s [25° C.] Polyol 6 Trimethylolpropane, OHN 1250 Polyol 7 Branched polyether/polyester, not containing EO, OHN 315, viscosity 1000 mPa .Math. s [25° C.] Catalyst 1 40% by weight solution of potassium acetate in dipropylene glycol (DPG) Catalyst 2 Phenol-blocked DBU Catalyst 3 LiCl-based composition, KX 146, BASF SE Defoamer 1 Xiameter ACP 1000 Antifoam Compound Zeolite 1 Zeolite dispersed in castor oil Isocyanate 1 Composition comprising 50% by weight of carbodiimide-modified diphenylmethane-4,4-diisocyanate (mean functionality 2.2, NCO content 29.5 g/100 g) and 50% by weight of isocyanate prepolymer based on diphenylmethane-4,4-diisocyanate, a polyether polyol (22.4-23.4 g/100 g) and dipropylene glycol Isocyanate 2 Composition comprising 99.9% by weight of isocyanate prepolymer based on diphenylmethane-4,4-diisocyanate, a polyether polyol (22.4-23.4 g/100 g) and dipropylene glycol and 0.1% by weight of dibis Isocyanate 3 Composition comprising 97.9% by weight of isocyanate prepolymer based on diphenylmethane-4,4-diisocyanate, a polyether polyol (22.4-23.4 g/100 g) and dipropylene glycol, 2% by weight of catalyst 3 and 0.1% by weight of dibis Isocyanate 4 Composition comprising 49.95% by weight of polymeric diphenylmethane-4,4-diisocyanate, 24.95% by weight of diphenylmethane-2,4-diisocyanate, 25% by weight of diphenylmethane-4,4-diisocyanate and 0.1% by weight of dibis TMPTA 1,1,1-Trihydroxymethylpropyl triacrylate Dibis Oxydiethylene bis(chloroformate) Epoxy resin 1 Epoxy resin based on bisphenol A and epichlorohydrin, epoxy equivalent weight 190 g/eq, determined according to ASTM D-1652. Viscosity at 25° C.: 12-14 Pa .Math. s, determined according to ASTM D445

[0267] 2. Test Methods

[0268] Shore D hardness test in accordance with DIN ISO 7619-1

[0269] 3-point bending test in accordance with DIN EN ISO 178

[0270] Tensile strength in accordance with DIN EN ISO 527

[0271] Elongation at break in accordance with DIN EN ISO 527

[0272] Charpy impact strength (flatwise) in accordance with DIN EN ISO 179-1/1fU

[0273] Heat deflection temperature: HDT-B-f, flatwise at 0.45 MPa in accordance with DIN EN ISO 75

[0274] Hydroxyl number (OH number, OH N): DIN 53240

[0275] Content of epoxy groups: SMS 2026

[0276] Viscosity: ASTM D445 (25° C.)

[0277] Shrinkage: Polyol and isocyanate are mixed at ambient temperature and the reaction mixture is poured into a metallic mold with dimensions of 1000 mm×20 mm×10 mm. Excess material is removed with a doctor blade. The reaction mixture is cured at 80° C. for 1 hour and at 120° C. for 2 hours. After cooling to ambient temperature, the part is removed from the mold. The length of the test bar is compared with the length of the mold.

[0278] 3. Production of Polyurethane Test Panels for Determination of the Mechanical Properties (Examples 1 to 5 and Comparative Examples 1 to 3)

[0279] Composition of the polyurethanes of examples 1 to 5 and comparative examples 1 to 3 as indicated in table 1. All starting materials apart from the isocyanate (usual batch size: 300 g of polyol composition) were mixed at ambient temperature under vacuum, then the isocyanate was added, followed by mixing for 60 s in the Speedmixer (FA Hauschild); subsequently the reaction mixture was poured into a metal mold of 20×30×0.4 cm or 20×30×0.2 cm, followed by scraping off the excess resin with a doctor blade and curing at 80° C. for 1 h, then at 120° C. for 2 h and at 180° C. for 2 h. Test specimens were subsequently milled from the material after storage for 1 week at ambient temperature.

[0280] 4. Production of a Fiber Composite Material from Polyurethane and Glass Fibers by Means of a Fiber Winding Process (Filament Winding Process) to Determine the Tendency to Form Bubbles at 80% Atmospheric Humidity (Examples 1 to 5 and Comparative Examples 1 to 3)

[0281] Composition of the polyurethanes of examples 1 to 5 and comparative examples 1 to 3 as indicated in table 1. A conventional fiber winding system (filament winding system), located within an enclosure with an extraction system, was used. The desired atmospheric humidity could be set within the enclosure via an air humidifier. A bobbin with continuous glass fibers, which was mounted inside the enclosure, was used. The glass fibers were guided through the as yet unfilled impregnation bath and then laid down on a mandrel via the laying head. The mandrel was clamped at both ends into the rotation device. The impregnation bath and the laying head were located on a carriage, by means of which fibers can be laid down over the length of the mandrel. The movement of the carriage, the rotation of the mandrel and the intended laying angle of the fibers on the mandrel as a function of time were programmed and then controlled by the winding software. The glass fibers used were SE3030 glass fibers from 3B (boron-free glass fibers, 17 μm filament diameter, tex 2400 (g/km)). The winding pattern chosen was: 2 circumferential plies, one ply +/−45° and two circumferential plies. The tests were carried out at a temperature of 25° C. and an atmospheric humidity of 85%. The resin impregnation bath was heated to 20° C. At the beginning of the test, all starting materials apart from the isocyanate (usual batch size: 100 g of polyol composition) were mixed at ambient temperature, after which the isocyanate was added and mixing was carried out for 60 s in a Speedmixer (FA Hauschild). The material was subsequently charged to the impregnation bath. Then the rove (the roving) was drawn manually so far until the resin-impregnated roving could be laid down on the mandrel and fixed there. Then the winding program was started and several plies of polyurethane-impregnated glass fibers were laid down on the mandrel. On conclusion of the winding process, the glass fiber was severed and the material was left to cure in the enclosure at ambient temperature for 1 hour. Curing was subsequently carried out at 80° C. for 1 hour and at 120° C. for 2 hours.

[0282] The quality of the component surface was visually assessed:

[0283] 1: smooth surface without microbubbles

[0284] 2: relatively smooth surface with a few microbubbles

[0285] 3: large number of microbubbles

[0286] 4: rough, foam-like component surface

[0287] 5: many air bubbles with a diameter >1 mm, white, foam-like component surface

TABLE-US-00002 TABLE 1 Composition of the polyurethanes of examples 1 to 5 and of comparative examples 1 to 3, and the properties thereof Comparative Example Comparative Example Example Example Example Comparative example 1 1 example 2 2 3 4 5 example 3 Polyol 1 [% by weight] 96.8 0 15 0 0 0 0 0 Polyol 2 [% by weight] 0 0 36.7 20 0 0 0 55.9 Polyol 3 [% by weight] 0 69.8 0 0 0 0 0 Polyol 4 [% by weight] 0 20 0 29.8 33.9 0 17.9 14 Polyol 5 [% by weight] 0 0 15 0 0 0 0 0 Polyol 6 [% by weight] 0 0 0 0 0 30.6 0 0 Polyol 7 [% by weight] 0 0 0 0 0 0 40 0 TMPTA [% by weight] 0 0 30 40 40 66.2 32 10 Epoxy resin 1 0 0 0 0 16 0 0 10 Catalyst 1 [% by weight] 0 0 0.1 0 0 0 0 Catalyst 2 [% by weight] 0 0 0 0.1 0 0 0 0 Defoamer 1 [% by weight] 0.2 0.2 0.2 0.1 0.1 0.2 0.1 0.1 Zeolite 1 [% by weight] 3 10 3 10 10 3 10 10 Isocyanate 1 [% by weight] 268 0 137 0 0 111 110.6 0 Isocyanate 2 [% by weight] 0 0 0 127 0 0 0 0 Isocyanate 3 [% by weight] 0 0 0 0 176.0 0 0 98 Isocyanate 4 [% by weight] 0 80 0 0 0 0 0 0 Isocyanate Index* 120 110 120 120 160 102 140 180 Shore D 85 81 82 83 87 87 87 82 Flexural strength [MPa] 78 101 114 129 139 67 127 97 Tensile strength [MPa] 35 60 64 84 63 24 77 56 Elongation at break [%] 2 11 6 8 3 1 6 9 Tensile modulus of elasticity [MPa] 3211 2350 2960 3660 3000 3100 2745 2036 Charpy impact strength 9.3 62.5 21 44 39 7 30 33 Heat deflection temperature HDT-B-f 108 70 115 118 136 155 126 86 Shrinkage [%] 0.9 0.9 0.8 0.9 0.9% 1.0 0.8 0.9 Tendency to form bubbles - Strong Almost Strong Almost Almost Almost None Almost winding test (25° C., 85% (4) none (4) none none none (1) none atmospheric humidity) (1-2) (1-2) (1-2) (1-2) (1-2) *Isocyanate index numerically determined from the % by weight or amounts of the components used, taking their functionalities into account

[0288] It could be shown that the use of at least 15% by weight of at least trifunctional alcohols, which exhibit at least two primary hydroxyl groups, preferably three primary hydroxyl groups, in particular of ethoxylated polyols, i.e. polyols which exhibit reactive primary hydroxyl groups, in the winding test led to significantly better results with regard to avoiding unwanted formation of bubbles: the polyurethanes based on at least 15% by weight of at least trifunctional alcohols, which exhibit at least two primary hydroxyl groups, preferably three primary hydroxyl groups, or at least 15% by weight of ethoxylated polyols, showed, in the winding test, despite high atmospheric humidity of 85%, no or at most very little formation of bubbles, whereas the use of propoxylated polyols or less than 15% by weight of the abovementioned polyols led to foaming, i.e. undesirable bubbles formed. The examples and comparative examples show that, in addition to the better processability in the winding process, there are advantages with regard to all of the mechanical properties considered, in particular with the impact strength.

[0289] Surprisingly, it could also be shown that a high isocyanate index can be used. A person skilled in the art would conventionally select the index such that there is no or only a minimal excess of isocyanate in an open winding process (isocyanate index 100-120). It is generally believed that a high isocyanate index increases the risk of undesirable reactions of the isocyanate with atmospheric moisture taking place during production. It has surprisingly been found that the polyol composition according to the invention makes it possible to use a high excess of isocyanate (index 99-400, preferably 100-250).

[0290] The examples and comparative examples show that, when the polyol composition according to the invention is used, surprisingly improved properties are also obtained with regard to a higher index—in particular with regard to heat deflection temperature—and surprisingly the processability/tendency to form bubbles is excellent despite the high index.

CITED LITERATURE

[0291] WO 03/085022 A1

[0292] WO 2016/183073 A1

[0293] M. Ionescu, Chemistry and Technology of Polyols, Rapra, 2005, pp 67-75 WO 18/036943 A WO 19/025439 A1

[0294] “Kunststoffhandbuch, Band 7, Polyurethane” [Plastics Handbook, Volume 7, Polyurethanes], Carl Hanser Verlag, 3rd Edition, 1993, Chapters 3.4.4 and 3.4.6 to 3.4.11 DE 102008021980 A1

[0295] WO 2009/115540 A1

[0296] Thomas Brock, Michael Groteklaes and Peter Mischke: Lehrbuch der Lacktechnologie

[0297] [Textbook of Paint Technology], Ed.: Ulrich Zorll, 2nd Edition, Vincentz Verlag, Hanover, 2000, ISBN 978-3-87870-569-7, Chap. 2.4.2.1, Defoamers and Deaerators, pp 169 et seq. “Handbook of Epoxy Resins” by Henry Lee and Kris Neville, McGraw-Hill Book Company, 1967

[0298] WO 2014/170252 A1

[0299] WO 2018/219756 A1