COMPACT ELASTOMER MOLDED PARTS ON THE BASIS OF POLYURETHANE

• US 20170198086A1
• Filed: 05/22/2015
• Published: 07/13/2017
• Est. Priority Date: 06/02/2014
• Status: Active Grant

• Current Assignee: BASF SE
• Original Assignee: BASF SE
• Inventors: Albuerne, Julio, Illguth, Rolf, Redl, Franz Xaver, Bremert, Bernd, Voelker, Hermann
• Granted Patent: US 10,597,483 B2
• Time in Patent Office: Days
• CPC Class Codes: B29C 45/0001 characterised by the choice of material
• CPC Class Codes: B29K 2075/00 Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2309/08 Glass
• CPC Class Codes: B29K 2509/02 Ceramics
• CPC Class Codes: B29K 2995/007 Hardness
• CPC Class Codes: B29L 2031/3005 Body finishings
• CPC Class Codes: B29L 2031/768 Protective equipment B29L2031/4821 takes precedence
• CPC Class Codes: C08G 18/10 Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• CPC Class Codes: C08G 18/246 containing also tin-carbon bonds
• CPC Class Codes: C08G 18/3206 aliphatic
• CPC Class Codes: C08G 18/42 Polycondensates having carboxylic or carbonic ester groups in the main chain
• CPC Class Codes: C08G 18/4238 derived from dicarboxylic acids and dialcohols
• CPC Class Codes: C08G 18/664 with compounds of group C08G18/3203
• CPC Class Codes: C08G 18/6666 Compounds of group C08G18/48 or C08G18/52
• CPC Class Codes: C08G 18/7671 containing only one alkylene bisphenyl group
• CPC Class Codes: C08G 18/797 containing carbodiimide and/or uretone-imine groups
• CPC Class Codes: C08G 18/82 Post-polymerisation treatment
• CPC Class Codes: C08G 2120/00 Compositions for reaction injection moulding processes
• CPC Class Codes: C08K 3/34 Silicon-containing compounds
• CPC Class Codes: C08K 5/098 Metal salts of carboxylic acids
• CPC Class Codes: C08K 7/14 : Glass
• CPC Class Codes: C08L 75/06 : from polyesters

Abstract

In a process for the production of pore-free polyurethane elastomer moldings with Shore D hardness of at least 60 in accordance with DIN 53505, (a) polyesterdiol with OH number from 20 to 100 mg KOH/g and (b) a chain extender composed of diol with molar mass below 300 g/mol, is mixed with (c) isocyanate prepolymers obtainable via reaction of diisocyanate with polyesterols with functionality from 1.95 to 2.2 and with OH number from 20 to 200 mg KOH/g to form a reaction mixture. The reaction mixture is charged to a mold and hardened to form the polyurethane elastomer. Polyurethane elastomer moldings are thus obtainable by this process, and these polyurethane moldings may be used as cladding component for commercial vehicles, bodywork component in vehicle construction, or a cladding component of a machine installation.

Claims

1. A process for the production of pore-free polyurethane elastomer moldings with a Shore D hardness of at least 60 in accordance with DIN 53505, the process comprising:

mixing

(a) a polyesterdiol with OH number from 20 to 100 mg KOH/g and

(b) a chain extender composed of diol with molar mass below 300 g/mol, with

isocyanate prepolymers obtainable via reaction of diisocyanate with polyesterols with functionality from 1.95 to 2.2 and with OH number from 20 to 200 mg KOH/g

to give a reaction mixture;

charging the mixture to a mold; and

hardening the mixture to form the polyurethane elastomer, wherein the ratio by weight of polyesterdiol (a) to chain extender (b) is in the range from 70;

30 to 40;

60.

2. The process according to claim 1, wherein the polyesterdiol (a) is obtainable via condensation of a as dicarboxylic acid component and of a diol component, wherein the dicarboxylic acid component comprises adipic acid.

3. The process according to claim 1, wherein the polyesterdiol is obtainable via condensation of a dicarboxylic acid and of a diol component where the diol component comprises diols having 4 to 8 carbon atoms.

4. The process according to claim 1, wherein the aliphatic isocyanate for the production of the isocyanate prepolymers (c) is diphenylmethane diisocyanate, inclusive of derivatives of diphenylmethane diisocyanate, with average functionality from 2.0 to 2.2.

5. The process according to claim 4, wherein the functionality of the diphenylmethane diisocyanate is 2.0.

6. The process according to claim 4, wherein the aromatic isocyanate for the production of the isocyanate prepolymers (c) is composed to an extent of 90% by weight of diphenylmethane 4,4′

-diisocyanate and carbodiimide-modified diphenylmethane 4,4′

-diisocyanate.

7. The process according to claim 1, wherein the reaction mixture comprises a nonionic surfactant as an emulsifier.

8. The process according to claim 1, wherein components (a) to (c) are mixed in a ratio to one another such that the isocyanate index is from 100 to 106.

9. The process according to claim 1, wherein polyesterdiol (a) and butanediol (b) are injected by the countercurrent method at a pressure of more than 100 bar into a mixing chamber, and are mixed there with the isocyanate prepolymers (c), and the resultant mixture is charged to a closed mold.

10. The process according to claim 1, wherein the chain extender (b) is 1,4-butanediol.

11. The process according to claim 1, wherein fillers and water-absorbent substances are used as additives.

12. A polyurethane molding obtainable by a process according to claim 1.

13. The use of a polyurethane molding according to claim 12 as cladding component for commercial vehicles, bodywork component in vehicle construction, or a cladding component of a machine installation.

14. The process according to claim 1 wherein the mixing step further comprises mixing the polyesterdiol (a), the chain extender (b) and the isocyanate prepolymers (c) with at least one of catalysts (d), emulsifiers (e) and other additives (f).