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KR-20260062983-A - Polyurethane-based elastomer foam suitable for battery potting

KR20260062983AKR 20260062983 AKR20260062983 AKR 20260062983AKR-20260062983-A

Abstract

The present invention provides a reaction system for manufacturing a polyurethane-based elastomer foam, comprising: a reaction system comprising: a component A) an isocyanate component comprising a hard block prepolymer as an isocyanate component; and a component B) an isocyanate-reactive component comprising a polyol, a first chain extender and a second chain extender different from the first chain extender, wherein the first chain extender and the second chain extender are aliphatic diols having 2 to 6 carbon atoms each, a blowing agent, optionally a surfactant, and optionally a catalyst.

Inventors

  • 베르베케 한스
  • 반 다이크 요한

Assignees

  • 헌트스만 인터내셔날, 엘엘씨

Dates

Publication Date
20260507
Application Date
20240830
Priority Date
20230911

Claims (20)

  1. As a reaction system for manufacturing a polyurethane-based elastomer foam, the reaction system Component A) an isocyanate component comprising a hard block prepolymer as an isocyanate component; and Component B) as an isocyanate-reactive component, i) Polyol; ii) a first chain extender and a second chain extender different from the first chain extender, wherein the first chain extender and the second chain extender are aliphatic diols having 2 to 6 carbon atoms each; iii) Injection agent; iv) optionally a surfactant; and v) Optionally catalyst isocyanate-reactive components including A reaction system including
  2. A reaction system according to claim 1, wherein the hard block prepolymer is formed from a reaction between an isocyanate composition and one or more isocyanate-reactive compounds each having a molar mass of less than 500 g/mol, and preferably the hard block prepolymer is an MDI-based prepolymer.
  3. A reaction system according to claim 1 or 2, wherein the NCO% of the hard block prepolymer is in the range of about 15% to about 30% and/or the average functionality of the hard block prepolymer is in the range of about 1.7 to about 2.3.
  4. A reaction system according to any one of claims 1 to 3, wherein the isocyanate component further comprises a polyisocyanate compound different from the hard block prepolymer, and preferably the polyisocyanate compound is a polymeric MDI.
  5. A reaction system according to claim 4, wherein the NCO% of the polyisocyanate compound is in the range of about 25% to about 40% and/or the average functional value of the polyisocyanate compound is in the range of about 2.4 to about 3.0.
  6. A reaction system according to claim 4 or 5, wherein the weight ratio of the hard block prepolymer to the polyisocyanate compound in the isocyanate component is in the range of 70:30 to 90:10.
  7. A reaction system according to any one of claims 1 to 6, wherein the polyol is a polyether polyol.
  8. A reaction system according to any one of claims 1 to 7, wherein the polyol has a hydroxyl value in the range of about 10 mg KOH/g to about 180 mg KOH/g, and/or has a weight-average molecular weight in the range of about 1000 g/mol to about 7500 g/mol, and/or has an average functional value in the range of about 2.0 to about 3.0.
  9. A reaction system according to any one of claims 1 to 8, wherein the first chain extender and the second chain extender are each a linear aliphatic diol, preferably any one independently selected from monoethylene glycol (MEG), diethylene glycol (DEG), 1,3-propanediol, 1,2-propanediol, 2-methyl-1,3-propanediol, 3-chloro-1,2-propanediol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, 2-ethyl-1,4-butanediol, 1,5-pentanediol, 1,3-pentanediol, 3-methyl-1,5-pentanediol, 2-methyl-2,4-pentanediol, 1,6-hexanediol, 1,2-hexanediol, and dipropylene glycol.
  10. A reaction system according to any one of claims 1 to 9, wherein the first chain extender and the second chain extender each have a molar mass in the range of about 60 to about 110 g/mol, and the molar mass of the first chain extender is less than the molar mass of the second chain extender.
  11. A reaction system according to any one of claims 1 to 10, wherein the first chain extender is monoethylene glycol (MEG) and/or the second chain extender is diethylene glycol (DEG).
  12. A reaction system according to any one of claims 1 to 11, wherein the polyol is present in component B in an amount ranging from about 65% by weight to about 90% by weight based on the total weight of component B and/or the first chain extender is present in component B in an amount ranging from about 5% by weight to about 15% by weight based on the total weight of component B and/or the second chain extender is present in component B in an amount ranging from about 4% by weight to about 10% by weight based on the total weight of component B.
  13. A reaction system according to any one of claims 1 to 12, wherein component A and component B are present in the reaction system in an amount such that when component A is mixed with component B, the isocyanate index is between about 75 and about 150.
  14. A reaction system according to any one of claims 1 to 13, wherein the polyurethane-based elastomer foam has a tensile strength at 23°C of at least about 3.0 MPa and/or has, the polyurethane-based elastomer foam has an elongation (%) at break at 23°C of at least about 50% and/or has, or the polyurethane-based elastomer foam has a modulus (12 mm/min, 0.1 to 2% strain) at 23°C of at least about 30 MPa.
  15. A reaction system according to any one of claims 1 to 14, wherein the polyurethane-based elastomer foam has a storage modulus (MPa) at -35°C / a storage modulus (MPa) at 100°C in the range of about 10 to about 150, or the polyurethane-based elastomer foam has a tangent delta of less than about 0.5 in a temperature range of -60°C to 200°C.
  16. A method for manufacturing a polyurethane-based elastomer foam, i) a step of forming a reactive mixture by mixing component A with component B as defined in a reaction system according to any one of claims 1 to 15; and ii) curing the above reactive mixture to form a polyurethane-based elastomer foam A method including
  17. Polyurethane-based elastomer foam that can be obtained by the method according to paragraph 16.
  18. A method for potting a battery pack comprising a plurality of battery cells, i) a step of forming a reactive mixture by mixing component A with component B as defined in a reaction system according to any one of claims 1 to 15; ii) a step of placing the above reactive mixture around a plurality of battery cells; and iii) curing the above reactive mixture to at least partially encapsulate a plurality of battery cells using a polyurethane-based elastomer foam. A method including
  19. A potted battery pack that can be obtained by the method according to paragraph 18.
  20. A reaction system according to any one of claims 1 to 15 or a polyurethane-based elastomer foam according to claim 17 for at least partially encapsulating a plurality of battery cells within a battery pack using the polyurethane-based elastomer foam.

Description

Polyurethane-based elastomer foam suitable for battery potting The present invention relates to a reaction system for manufacturing a polyurethane-based elastomer foam. The present invention also relates to a method for manufacturing a polyurethane-based elastomer foam, a polyurethane-based elastomer foam, a method for potting a battery pack, a potted battery pack, and a reaction system in battery potting or a use of the polyurethane-based elastomer foam. Polyurethane-based elastomer foam is particularly suitable for use as a potting material for battery packs designed for automobiles, such as electric vehicles. Polyurethane-based elastomer foams are used for various purposes. One of them is as a battery potting material (or battery encapsulation material). Battery potting is a process of partially or completely filling a battery pack or mold containing battery cells with a material to at least partially encapsulate or surround the battery cells with said material. Generally, the purpose of battery potting is to protect the battery cells by, for example, providing resistance to mechanical shock and vibration, creating a seal against moisture, solvents, and corrosive agents, and assisting in electrical insulation and heat dissipation. Battery potting is particularly important for battery packs used in electric vehicles (EVs), which contain numerous battery cells requiring protection from harsh conditions such as large temperature fluctuations, mechanical shock, vibration, and moisture. Therefore, battery potting materials must be lightweight and easy to process, while possessing excellent mechanical properties over a wide temperature range, particularly tensile properties (e.g., tensile strength, modulus (also known as Young's modulus), and elongation at break), to operate effectively in EVs. However, current battery potting materials may be too brittle to provide stable properties over the required temperature range, or they may fail to provide the desired level of elongation over the required temperature range. The inability of current battery potting materials to exhibit desired tensile properties over the required temperature range limits their effectiveness as battery potting materials, particularly in EVs. For example, polysiloxane (silicon) materials can be used as battery potting materials. However, the modulus of silicon polymers is often lower than the modulus required to be effective when used in EVs. Furthermore, silicon is expensive, and its processability is generally more difficult than that of other materials, such as polyurethane-based elastomers. As the demand for EVs increases, the demand for effective new battery potting materials is also rising. Consequently, there is increasing demand for polyurethane-based elastomer foams that offer improved tensile properties (e.g., tensile strength, modulus, and elongation at break) and provide an ideal balance of tensile and chemical properties for use as battery potting materials in EVs. Therefore, there is a demand for a polyurethane-based elastomer foam that can be used as a battery potting material and has an ideal balance of tensile properties (e.g., tensile strength, modulus, and elongation at break) and chemical properties for battery potting materials, particularly for EV battery potting materials. The present invention addresses the aforementioned problems and requirements. In a first aspect, a reaction system for manufacturing a polyurethane-based elastomer foam is provided, comprising: an isocyanate component A) comprising a hard block prepolymer as an isocyanate component; and a reaction system comprising an isocyanate-reactive component B) comprising a polyol as an isocyanate-reactive component; a chain extender comprising a first chain extender and a second chain extender different from the first chain extender, wherein the first chain extender and the second chain extender are each an aliphatic diol having 2 to 6 carbon atoms; a blowing agent; optionally a surfactant; and optionally a catalyst. Surprisingly, the inventors have discovered that a polyurethane-based elastomer foam having an ideal balance of properties for use as a battery potting material can be produced using the aforementioned reaction system. Specifically, the polyurethane-based elastomer foam obtained from the reaction system possesses high tensile strength and high elongation at break, as well as a high modulus (Young's modulus), which, interestingly, maintains these beneficial tensile properties over a wide temperature range. It is particularly surprising that the foam possesses both relatively high elongation at break and a relatively high modulus over a wide temperature range. A polyurethane-based elastomer foam having this combination of tensile properties is an excellent choice for battery potting materials, particularly for EV battery potting materials. This is because the foam possesses high strength, high deformation capacity, and appropriate stiffness, ther