Composite elements composed from thermoplastic polymers and polyurethanes, and process for production thereof

Abstract

The invention relates to composite elements comprising a thermoplastic polymer and an adjacent polyurethane bonded thereto, to a process for production thereof and to the use thereof.

Claims

1. A composite element comprising (a) a thermoplastic adhered to (b) a product of the reaction of a reaction mixture consisting of (i) one or more isocyanates, (ii) one or more polyester polyols with functionality greater than 3, an ester group concentration of from 9 to 10 mol per 1 kg/polyester polyol, and a hydroxy number of from 60 to 150 mg KOH/g, based on the condensation of adipic acid or adipic acid and isophthalic acid or adipic acid and phthalic acid or adipic acid and isophthalic acid and phthalic acid with ethylene glycol and at least one or more diols from the group consisting of 1,2-propanediol, 1,4-butanediol, and 1,6-hexanediol and trimethylolpropane, (iii) one or more polyether polyols, and (iv) optionally a chain extender and/or a crosslinking agent, optionally in the presence of (v) a catalyst, (vi) a blowing agent and/or (vii) an auxiliary and/or an additive.

2. The composite element as claimed in claim 1 comprising, as a thermoplastic (a) one or more plastics selected from the group consisting of polyethylene, polypropylene, styrene-maleic anhydride copolymer (SMA), thermoplastic polyurethane (TPU), polycarbonate (PC), styrene-acrylonitrile (SAN), acrylonitrile-butadiene-styrene (ABS), polyvinylchloride (PVC), and blends thereof.

3. The composite element as claimed in claim 1, wherein the one or more polyester polyol is a condensate of adipic acid or adipic acid and isophthalic acid and/or phthalic acid with ethylene glycol and 1,2-propanediol and at least one or more diols from the group consisting of 1,4-butanediol and 1,6-hexanediol and trimethylolpropane.

4. The composite element as claimed in claim 1, wherein the quantitative proportions present of the polyester polyol are from 0.5 to 5% by weight, based on the entirety of components (i) to (vii).

5. The composite element as claimed in claim 1 with an adhesion rolling peel resistance of at least 0.30 N/mm of composite element width measured by a method based on DIN 53 357 A; force per unit of composite element width, between the thermoplastic (a) and the product (b).

6. The composite element as claimed in claim 1, wherein the amount of ethylene glycol is from 3 to 20% by weight, based on 100 parts by weight of the ester produced, or, if ethylene glycol and propylene glycol are present together, the amount of propylene glycol is from 10 to 30% by weight, based on 100 parts by weight of the ester produced, and the amount of trimethylolpropane is from 5 to 15% by weight, based on 100 parts by weight of the ester produced.

7. The composite element as claimed in claim 1, wherein the amount of adipic acid is from 60 to 82 mol %, and the amount present of isophthalic and/or phthalic acid is from 18 to 40 mol %.

8. The composite element as claimed in claim 1, wherein the equivalence ratio of NCO groups from (i) to the entirety of the reactive hydrogen atoms from (ii) and (iii) and optionally (iv) is from 0.3:1 to 1.8:1.

9. A process for producing the composite element as claimed in claim 1 comprising adhering to a thermoplastic (a) a polyisocyanate polyaddition product (b), wherein the polyisocyanate polyaddition product is produced by reaction of a reaction mixture consisting of (i) one or more isocyanates, (ii) one or more polyester polyols with functionality greater than 3, ester group concentration of from 9 to 10 mol/kg of ester, and a hydroxy number of from 60 to 150 mg KOH/g, based on the condensation of adipic acid or adipic acid and isophthalic acid and/or phthalic acid with ethylene glycol and at least one or more diols from the group consisting of 1,2-propanediol, 1,4-butanediol and 1,6-hexanediol and trimethylolpropane, (iii) one or more polyether polyols, (iv) optionally a chain extender and/or a crosslinking agent, optionally in the presence of (v) a catalyst, (vi) a blowing agent and/or (vii) an auxiliary and/or an additives in the presence of (a).

10. The process for producing the composite element as claimed in claim 9, wherein the one or more polyester polyols has an ester group concentration of from 9.2 to 9.8 mol/kg of ester.

11. A method comprising utilizing the composite element as claimed in claim 1 in a component in vehicle construction, aircraft construction, or in the construction industry.

12. A component in vehicle construction or in aircraft construction or in the construction industry comprising the composite element as claimed in claim 1.

Description

EXAMPLES

(1) Analyses methods were as follows:

(2) Dynamic viscosity: using a MCR 51 rheometer from Anton Paar in accordance with DIN 53019 with a CP 50-1 cone (diameter 50 mm, angle 1) at shear rates of 25, 100, 200, and 500 s.sup.1.

(3) Hydroxy number: method based on the DIN 53240 standard

(4) Acid number: method based on the DIN 53402 standard

(5) Separation force: method based on the DIN 53 357-A standard

(6) Key to materials and abbreviations used:

(7) PET A: Glycerol-started polyether polyol having terminal ethylene oxide block (14% by weight) with OH number of 35 mg KOH/g and with nominal functionality of 3.

(8) PET B: Glycerol-started polyether polyol having terminal ethylene oxide block (19% by weight) with OH number of 35 mg KOH/g and with nominal functionality of 3.

(9) PET C: Ethylenediamine-started polypropylene oxide with OH number of 630 KOH/g and with nominal functionality of 4.

(10) SAN polyol: Hyperlite Polyol 1650; polyether polyol with solids content of about 42% by weight of styrene-acrylonitrile copolymer and with hydroxy number of about 20 mg KOH/g from Bayer MaterialScience AG.

(11) Carbon black: ISOPUR N black paste from iSL-Chemie.

(12) Diethyltolylene-diamine: From Albemarle.

(13) Jeffcat ZF10: Incorporable catalyst from Huntsman; N,N,N-trimethyl-N-hydroxyethyl-bisaminoethyl ether.

(14) Dabco NE-1070: N-[3-(dimethylamino)propyl)urea from Air Products.

(15) Isocyanate: Diphenylmethane diisocyanate mixture from Bayer MaterialScience AG with NCO content of 32% by weight of NCO, comprising from 0.05 to 0.5% by weight of 2,2-MDI, from 5.5 to 7.5% by weight of 2,4-MDI, from 50 to 54% by weight of 4,4-MDI, and also higher MDI homologs.

(16) Foil used comprised a skin produced by the slush process and based on DSY 260/02 PVC powder from Arkema.

(17) A) Synthesis of the Polyester Polyol A-2 Used as Adhesion Promoter:

(18) The appropriate acid (acid derivative), monoethylene glycol, optionally 1,2-propanediol, optionally 1,6-hexanediol, optionally 1,4-butanediol and 1,1,1-trimethylolpropane were used as initial charge under a blanket of nitrogen in a 6-liter four-necked flask equipped with heating mantle, mechanical stirrer, internal thermometer, 40 cm packed column, column head, descending high-performance condenser, and also membrane vacuum pump, and were heated to 200 C. with slow stirring, whereupon water of reaction was removed by distillation. After 5 hours, the pressure was reduced continuously over a period of 6 hours to a final value of 15 mbar, and the reaction was completed as far as a total reaction time of 30 hours. Table 1 below shows the quantities used and the data.

(19) TABLE-US-00001 TABLE 1 Quantities and analysis data for the polyester polyols produced A-1 Polyester polyol (comp) A-2 A-3 A-4 A-5 A-6 A-7 Polycarboxylic acids: Adipic acid [pts. by wt.] 63.81 69.97 71.54 44.99 46.02 68.59 69.97 Phthalic anhydride [pts. by wt.] Isophthalic acid [pts. by wt.] 25.57 26.15 Adipic acid [mol %] 100 100 100 67 67 100 100 Phthalic anhydride [mol %] Isophthalic acid [mol %] 33 33 Polyalcohols: Ethylene glycol [pts. by wt.] 6.16 6.18 6.41 6.35 6.14 6.16 1,2-Propanediol [pts. by wt.] 14.45 20.9 21.78 18.99 20.05 20.13 20.9 1,4-Butanediol [pts. by wt.] 1,6-Hexanediol [pts. by wt.] 27.56 11.72 11.76 12.2 12.09 11.69 11.72 1,1,1-Trimethylolpropane [pts. by wt.] 9.91 8.49 6.36 8.46 6.35 10.35 8.49 Total [pts. by wt.] 115.72 117.24 117.62 116.62 117 116.9 117.24 Water removed [pts. by wt.] 15.72 17.24 17.62 16.62 17 16.9 17.24 Ester quantity [pts. by wt.] 100 100 100 100 100 100 100 Data: OH number, found [mg KOH/g] 109 92.05 74.9 94.07 74 112.15 92.05 Acid number, found [mg KOH/g] 0.5 0.51 0.57 0.29 0.32 0.55 0.51 Mol of ester groups per kg [mol/kg] 8.7 9.6 9.8 9.2 9.4 9.4 9.6 Viscosity, 75 C. [mPa * s] 650 2880 3290 7950 not det. 1220 2880 Functionality 3.2 3.1 3.1 3.1 3.1 3.1 3.1 Polyester polyol A-8 A-9 A-10 A-11 A-12 A-13 Polycarboxylic acids: Adipic acid [pts. by wt.] 52.83 71.54 46.45 44.99 46.02 68.59 Phthalic anhydride [pts. by wt.] 17.83 Isophthalic acid [pts. by wt.] 26.4 25.57 26.15 Adipic acid [mol %] 75 100 67 67 67 100 Phthalic anhydride [mol %] 25 Isophthalic acid [mol %] 33 33 33 Polyalcohols: Ethylene glycol [pts. by wt.] 14.74 6.18 14.62 6.41 6.35 6.14 1,2-Propanediol [pts. by wt.] 21.78 18.99 20.05 20.13 1,4-Butanediol [pts. by wt.] 21.4 21.23 1,6-Hexanediol [pts. by wt.] 11.76 12.2 12.09 11.69 1,1,1-Trimethylolpropane [pts. by wt.] 10.55 6.36 8.46 8.46 6.35 10.35 Total [pts. by wt.] 117.35 117.62 117.17 116.62 117 116.9 Water removed [pts. by wt.] 17.35 17.62 17.17 16.62 17 16.9 Ester quantity [pts. by wt.] 100 100 100 100 100 100 Data: OH number, found [mg KOH/g] 109.8 74.9 92.16 94.07 74 112.15 Acid number, found [mg KOH/g] 0.81 0.57 0.74 0.29 0.32 0.55 Mol of ester groups per kg [mol/kg] 9.6 9.8 9.5 9.2 9.4 9.4 Viscosity, 75 C. [mPa * s] 2880 3290 8900 7950 not det. 1220 Functionality 3.1 3.1 3.1 3.1 3.1 3.1
B) Production of the Composite Elements

(20) The composite elements were produced at a mold temperature of 45 C. in an aluminum mold measuring 20020020 mm which had a lining of Teflon foil and which could be sealed with a lid. A PVC foil (2002001.2 mm) was placed on the floor of the mold. The temperature of both components (polyol component and isocyanate component) was 23 C. The components of the polyol side were first mixed with a Pendraulic stirrer in a paper cup, and then the isocyanate was added and the mixture was mixed for about 10 seconds. The mixture was then poured into the open mold and this was sealed, the amount of reacting melt having been selected so as to give an average envelope density of 120 g/l for the foam. After about 10 minutes, the material was demolded and the composite element was stored at room temperature for 24 hours. Strips of width 20 mm were then cut from the material. The adhesion properties (adhesion between PVC foil and polyurethane) of said strips were then tested.

(21) TABLE-US-00002 TABLE 2 Formulations and properties of the composite elements Example B-1 (comp) B-2 B-3 B-4 B-5 B-6 B-7 B-8 B-9 B-10 B-11 B-12 B-13 Polyol side: PET A [pts. by wt.] 30.4 30.4 30.4 30.4 30.4 30.4 30.4 30.4 30.4 30.4 30.4 30.4 30.4 PET B [pts. by wt.] 55 55 55 55 55 55 55 55 55 55 55 55 55 PET C [pts. by wt.] 2 2 2 2 2 2 2 2 2 2 2 2 2 Styrene-acrylonitrile [pts. by wt.] 3.35 3.35 3.35 3.35 3.35 3.35 3.35 3.35 3.35 3.35 3.35 3.35 3.35 copolymer Carbon black [pts. by wt.] 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Diethyltolylenediamine [pts. by wt.] 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95 Water [pts. by wt.] 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.1 Polyol A-1(comp) [pts. by wt.] 5 Polyol A-2 [pts. by wt.] 3 Polyol A-3 [pts. by wt.] 3 Polyol A-4 [pts. by wt.] 3 Polyol A-5 [pts. by wt.] 3 Polyol A-6 [pts. by wt.] 3 Polyol A-7 [pts. by wt.] 3 Polyol A-8 [pts. by wt.] 3 Polyol A-9 [pts. by wt.] 3 Polyol A-10 [pts. by wt.] 3 Polyol A-11 [pts. by wt.] 3 Polyol A-12 [pts. by wt.] 3 Polyol A-13 [pts. by wt.] 3 Jeffcat ZF10 [pts. by wt.] 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Dabco NE1070 [pts. by wt.] 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 Isocyanate side: Isocyanate [pts. by wt.] 42.64 42.05 41.93 42.06 41.93 42.18 42.05 42.16 41.93 42.05 42.06 41.93 42.18 Rolling peel resistance 0.18 0.34 0.41 0.42 0.44 0.45 0.34 0.37 0.41 0.42 0.42 0.44 0.45 (adhesion between PVC foil and PUR) by method based on DIN 53 357-A (measured on specimens of width 2 cm)

(22) Separation force is determined in newtons. In order to improve comparability between specimens of different width, values have been standardized to a strip width of 1 mm by dividing the force observed by the width of the strips in mm.

(23) As can be seen from Table 2, no useful adhesion is achieved when the ester A-1 (comp) is used.

(24) In contrast, the other esters provide markedly better adhesion values.