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EP-4741431-A1 - A MULTIPLE-COMPONENT POLYURETHANE COMPOSITION AND USE THEREOF

EP4741431A1EP 4741431 A1EP4741431 A1EP 4741431A1EP-4741431-A1

Abstract

1. A multiple-component polyurethane composition composed of a first component A and a second component B, wherein the first component A comprises: a) At least one polyol PO having an average hydroxyl number determined according to ISO 4629-2:2016 standard of 350 - 1500 mg KOH/g, preferably 450 - 1000 mg KOH/g and the second component B comprises: b) At least one aromatic polyisocyanate PI, and wherein the at least one polyol PO is a tetra- or higher functional polyol containing at least one tertiary amine group , preferably one or two tertiary amine groups and wherein the first component A comprises at least 10 wt.-%, preferably at least 15 wt.-%, of the at least one polyol PO.

Inventors

  • Liang, Shuyu
  • CHOFFAT, FABIEN
  • LABOUREIX, Gabriel
  • SCHLUMPF, MICHAEL

Assignees

  • Sika Technology AG

Dates

Publication Date
20260513
Application Date
20241107

Claims (17)

  1. A multiple-component polyurethane composition comprising a first component A and a second component B, wherein the first component A comprises: a) At least one polyol PO having an average hydroxyl number determined according to ISO 4629-2:2016 standard of 350 - 1500 mg KOH/g, preferably 450 - 1000 mg KOH/g and the second component B comprises: b) At least one aromatic polyisocyanate PI, and wherein the at least one polyol PO is a tetra- or higher functional polyol containing at least one tertiary amine group, preferably one or two tertiary amine groups and wherein the first component A comprises at least 10 wt.-%, preferably at least 15 wt.-%, of the at least one polyol PO.
  2. The multiple-component polyurethane composition according to claim 1 having in its cured state a glass transition temperature (T g ) determined by dynamical mechanical analysis (DMA) in accordance with ISO 6721-11:2019 standard of at or above 135 °C, preferably at or above 150 °C.
  3. The multiple-component polyurethane composition according to any one of previous claims, wherein the at least one polyol PO is a compound of formula (I) where R 1 represents a linear or branched alkyl group with 2 to 12 carbon atoms, preferably 2 to 8 carbon atoms and R 2 , R 3 , R 4 , and R 5 each represent linear or branched alkyl group with 2 to 18 carbon atoms, preferably 2 to 12 carbon atoms, substituted with one or more hydroxy groups and optionally containing one or more ether groups.
  4. The multiple-component polyurethane composition according to any one of previous claims, wherein the proportion of the at least one polyol PO makes up at least 35 wt.-%, preferably at least 50 wt.-%, of the total weight of all polyols contained in the first component A.
  5. The multiple-component polyurethane composition according to any one of previous claims, wherein the at least one polyol PO comprises at least one alkoxylated alkylene diamine PO1, preferably selected from N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine, N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine, 1,1',1",1‴-((2-methylpentane-1,5-diyl)bis(azanetriyl))tetrakis(propan-2-ol),3,3',3'',3‴-((2-methylpentane-1,5-diyl)bis(azanetriyl))tetrakis(propane-1,2-diol), 4-[8-hydroxy-3-(2-hydroxypropyl)-5-methyl-6-oxa-3-azanonyl]-4-aza-2,6-heptanediol, and 1-({3-[bis(2-hydroxypropyl)amino]-2-tolyl}(2-hydroxypropyl)amino)-2-propanol.
  6. The multiple-component polyurethane composition according to any one of previous claims, wherein the at least one aromatic polyisocyanate PI has an isocyanate content determined according to ISO 11909:2007 standard of 15 - 50 wt.-%, preferably 20 - 45 wt.-% and/or a viscosity determined according to ISO 3219-1:2021 standard of 100 - 500 mPa s, preferably 150 - 400 mPa·s and/or an average isocyanate functionality determined according to ISO 14896-2009 standard method A of 2.0 - 4.0, preferably 2.2 - 3.8.
  7. The multiple-component polyurethane composition according to any one of previous claims, wherein the at least one aromatic polyisocyanate PI is selected from monomers, oligomers, polymers, and derivatives of methylene diphenyl diisocyanate (MDI) and monomers, oligomers, polymers, and derivatives of toluene diisocyanate (TDI).
  8. The multiple-component polyurethane composition according to any one of previous claims, wherein the proportion of monomers of methylene diphenyl diisocyanate (MDI) and/or proportion of monomers of toluene diisocyanate (TDI) is not more than 50 wt.-%, preferably not more than 35 wt.-%, based on the total weight of the at least one aromatic polyisocyanate PI.
  9. Use of the multiple-component polyurethane composition according to any one of previous claims as an adhesive, sealant, coating, as a block material or paste for tooling, modeling, or mould making, or as a 3D printing material.
  10. A method for producing a three-dimensional object comprising the steps of: - providing a multiple-component polyurethane composition according to any one of claims 1-8 - mixing the first component A and the second component B with each other in a mixer to give a curable polyurethane composition, and - applying the curable polyurethane composition layer-by-layer using a movable print head of an additive manufacturing device to prepare a shaped body from a cured polyurethane composition.
  11. The method according to claim 10 comprising a further step of subjecting at least a portion of a surface of the shaped body to a mechanical treatment step to reduce surface roughness.
  12. A method for producing a three-dimensional article comprising the steps of: - providing a multiple-component polyurethane composition according to any one of claims 1-8, - mixing the first component A and the second component B with each other in a mixer to give a curable polyurethane composition, and - applying the curable polyurethane composition into a mould, - curing the applied composition to form a shaped body composed of a cured polyurethane composition, and - removing the shaped body from the mould.
  13. The method according to claim 12 comprising a further step of subjecting the shaped body to one or more mechanical processing steps, preferably selected from cutting, sawing, milling, threading, water jet or laser treatment, grinding, brushing, polishing, and abrasive blasting.
  14. Use of the three-dimensional object or the three-dimensional article obtained by using the method according to any one of claims 10-13 as a mold, preferably as a prepreg mold, or as a pattern, tool, prototype, master model, core model, or a negative model.
  15. Use of at least one polyol PO having an average hydroxyl number determined according to ISO 4629-2:2016 standard of 350 - 1500 mg KOH/g, preferably 450 - 1000 mg KOH/g to increase a glass transition temperature (T g ) determined by dynamical mechanical analysis (DMA) in accordance with ISO 6721-11:2019 standard of a cured polyurethane composition obtained by mixing a first and a second component of a multiple-component polyurethane composition with each other and letting the thus obtained mixture to cure, wherein the at least one polyol PO is a tetra- or higher functional polyol containing at least one tertiary amine group, preferably one or two tertiary amine groups.
  16. Use according to claim 15, wherein the proportion of the at least one polyol PO makes up at least at least 35 wt.-%, preferably at least 50 wt.-%, of the total weight of all polyols contained in the first component of the multiple-component polyurethane composition.
  17. Use according to claim 15 or 16, wherein the second component of the multiple-component polyurethane composition comprises at least one polyisocyanate PI, preferably an aromatic polyisocyanate.

Description

Technical field The invention relates to multiple-component polyurethane compositions and use of them as modelling and tooling materials or for producing three-dimensional objects by using additive manufacturing or a mass casting processes. The invention relates particularly to multiple-component polyurethane compositions, which can be cured at room temperature or elevated temperature and which in their cured state have a high glass transition temperature. Background art Polyurethane polymers are widely used for providing different types of products including, for example, foams, coatings, adhesives, sealants, electrical potting compounds, fibers as well as models, designs and tools. Reactive polyurethane compositions can be provided as single- or multiple component compositions, which typically contain monomeric, oligomeric, or polymeric compounds including one or more types of functional groups that react with each other or with other substances, such as with atmospheric moisture. For example, a multiple-component reactive polyurethane composition may comprise a first component with isocyanate-reactive compounds, such as oligomers or polymers with reactive functional groups, particularly hydroxyl groups, whereas the second component comprises one or more different types of polyisocyanates, i.e., compounds with free isocyanate groups. Upon curing of a reactive polyurethane composition, polyurethane polymers are first formed in reactions between polyisocyanates and polyols. In the second step, polyurethane polymers react with crosslinkers, such as amine crosslinkers or with atmospheric moisture, to give a crosslinked network structure. Curable epoxy and polyurethane compositions are also used for making of models, prototypes, tools, foundry patterns, cold core boxes, and moulds for use in automotive, marine and aeronautics industries. In a conventional process, the composition is provided as a board (block material), which is then mechanically processed, for example, by cutting and/or milling, into the final design, such as a prototype, model, or a tool, for example a mould. The boards having a standardized size are commonly known as design, styling, model, tooling, and foundry tooling boards. The traditional production process has the disadvantage of a considerable processing time and a high amount of waste material, which is produced during the cutting and/or milling steps. The amount of waste material can be reduced by using a mass casting process but this requires the use of moulds having an individualized shape for each design. Furthermore, mass casting has limitations in terms of the maximum size and variability of shapes to be produced. Additive manufacturing (AM) techniques are widely used in various industries to create physical prototypes as well as end-use parts. According to ISO 52900 standard, AM is a "process of joining materials to make parts from 3D model data, usually layer upon layer". AM techniques provide an alternative to conventional manufacturing processes, in which, for example, material is molded or subtracted by milling to create a three-dimensional (3D) object. Generally, in an AM process a 3D article is manufactured using a shapeless material (e.g. liquids, powders, granules, pastes, etc.) and/or a shape-neutral material (e.g. bands, wires, filaments) that is subjected to chemical and/or physical processes (e.g. melting, polymerization, sintering, curing or hardening). The main categories of additive manufacturing technologies include VAT photopolymerization, material extrusion, material jetting, binder jetting, powder bed fusion, direct energy deposition, and sheet lamination techniques. Additive manufacturing is also known as rapid prototyping, on-demand manufacturing, digital fabrication, solid freeform manufacturing, or 3D printing. In an AM process, the material is deposited, applied or solidified under computer control based on a digital model of the 3D object to be produced, to create 3D object. The digital model of the 3D article can be created, for example, by using a CAD software or a 3D object scanner. The deposition, application and/or consolidation of the material, for example a curable composition, is carried out in particular on the basis of a data model of the object to be generated and in particular layer-by-layer. There has also been some attempts to use chemically curable polymer compositions as printing materials in an AM process with the objective of improving the chemical and physical properties of the prepared 3D objects. The chemical basis for such printing materials is, for instance, RTV-2 silicones, or multiple-component epoxy and polyurethane compositions. Multiple-component reactive compositions have some advantages when used in 3D printing processes since the highly reactive constituents, such as curing agents and binders, can be provided in separate components and the curing process begins only after mixing of the two components with each other. In t