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CN-122011483-A - Preparation method of PIR material by carbon dioxide assisted water foaming

CN122011483ACN 122011483 ACN122011483 ACN 122011483ACN-122011483-A

Abstract

The invention provides a preparation method of a PIR material by carbon dioxide assisted water foaming, which comprises the following steps of S1, filling polyester polyol and polyether polyol into a reaction kettle, adding a foam stabilizer, a chemical foaming agent, a foaming catalyst, a flame retardant and a chemical foaming agent, then injecting liquid carbon dioxide to obtain a component A, S2, taking isocyanate as a component B, mixing the component A and the component B according to the weight ratio of 1 (1.7-2), and foaming and forming by a high-pressure foaming machine. The invention adopts carbon dioxide to assist water foaming, takes water as a main chemical foaming agent, and introduces liquid carbon dioxide as a physical foaming agent to carry out collaborative foaming, and the liquid carbon dioxide can generate a large number of uniform bubble nucleation points at the mixing moment, which is helpful to form a finer and more uniform closed cell structure, and is the basis for obtaining excellent heat insulation and mechanical properties.

Inventors

  • YANG SHENGJUN
  • Ding Yingfa

Assignees

  • 江苏华桑绝热科技有限公司
  • 常州寒磊新材料科技有限公司

Dates

Publication Date
20260512
Application Date
20251222

Claims (10)

  1. 1. The preparation method of the PIR material by carbon dioxide assisted water foaming is characterized by comprising the following steps of: S1, filling polyester polyol and polyether polyol into a reaction kettle, adding a foam stabilizer, a chemical foaming agent and a foaming catalyst, and then injecting liquid carbon dioxide to obtain a component A; s2, taking isocyanate as a component B, mixing the component A and the component B according to the weight ratio of 1 (1.7-2), and foaming and molding by a high-pressure foaming machine.
  2. 2. The method for preparing PIR material by carbon dioxide assisted water foaming according to claim 1, wherein in step S1, the injection pressure of liquid carbon dioxide is 5-15 MPa, and the material temperature is controlled at 20-40 ℃.
  3. 3. The method for preparing the PIR material by carbon dioxide-assisted water foaming according to claim 1, wherein in the step S1, the component A comprises, by weight, 20-40 parts of polyester polyol, 10-30 parts of polyether polyol, 1-3 parts of a foaming catalyst, 1-3 parts of a foam stabilizer, 1-3 parts of a chemical foaming agent and 3-10 parts of liquid carbon dioxide.
  4. 4. A method for preparing a PIR material by carbon dioxide assisted water foaming according to any one of claims 1 to 3, wherein the chemical foaming agent is deionized water.
  5. 5. A method for preparing a PIR material foamed with carbon dioxide-assisted water according to any one of claims 1 to 3, wherein the foam stabilizer is a polysiloxane-polyether copolymer.
  6. 6. A method for preparing a PIR material by carbon dioxide assisted water foaming according to any one of claims 1 to 3, wherein the foaming catalyst is a trimerisation catalyst or an organometallic salt catalyst.
  7. 7. The method for preparing the PIR material by carbon dioxide-assisted water foaming according to claim 1, wherein the step S2 is characterized by further comprising the step of preparing a C component, wherein the C component comprises an epoxy compound and polyetheramine in a weight ratio of (5-8): 1, and then mixing and foaming the A component, the B component and the C component in a weight ratio of (1.7-2): 1-1.5 by a high-pressure foaming machine to form.
  8. 8. The method for preparing a carbon dioxide-assisted water-blown PIR material according to claim 7, wherein the C component further comprises tetrabutylammonium bromide, and the weight ratio of tetrabutylammonium bromide to polyetheramine is (0.5-1): 1.
  9. 9. The method for preparing PIR material by carbon dioxide assisted water foaming according to claim 1, wherein in step S2, the mixing pressure is 10-20 MPa, and the material temperature is controlled at 20-30 ℃.
  10. 10. The method for preparing the PIR material by carbon dioxide-assisted water foaming according to claim 1, wherein the step S2 is characterized in that the PIR material is further subjected to curing treatment in an oven at 70-80 ℃ for 2-4 hours after foaming and molding.

Description

Preparation method of PIR material by carbon dioxide assisted water foaming Technical Field The invention relates to the technical field of PIR materials, in particular to a preparation method of a PIR material by carbon dioxide assisted water foaming. Background PIR (Polyisocyanurate Foam) is entitled "polyisocyanurate", also known as "polyisocyanurate foam PIR" or "trimer PIR". PIR is a foaming material prepared by reacting isocyanate with polyether after the catalytic action, and has better physical and fireproof properties than common polyurethane. Is an ideal organic low-temperature heat insulation material, and has the advantages of small heat conductivity, light weight, shock resistance and strong adaptability. It is widely used in oil refinery, chemical plant, ethylene, chemical fertilizer, cold storage and heat insulation in building industry. PIR foaming processes typically employ chemical foaming or physical foaming. Chemical foaming generally employs water as a blowing agent, which reacts with excess isocyanate to form carbon dioxide gas and polyurea, and the carbon dioxide formed forms a bubble core in the system and expands with the reaction to ultimately form the cell structure of the foam. The amine resulting from the reaction will further react with the isocyanate to form polyurea linkages which form part of the polymer backbone of the foam. In the physical foaming process, pentane is usually used as a foaming agent, and is liquid at normal temperature and pressure, and in the foaming process, the pentane does not react chemically, but is quickly evaporated and gasified by virtue of reaction heat generated during the mixing of polyurethane raw materials, and the volume is severely expanded, so that the liquid mixture is blown into foam plastics. However, the foaming process has the defects of low foam dimensional stability, unstable performances such as aging and the like. Disclosure of Invention In order to solve the problems, the invention provides a preparation method of a PIR material by carbon dioxide assisted water foaming, which comprises the following steps: S1, filling polyester polyol and polyether polyol into a reaction kettle, adding a foam stabilizer, a chemical foaming agent, a foaming catalyst, a flame retardant and a chemical foaming agent, and then injecting liquid carbon dioxide to obtain a component A; s2, taking isocyanate as a component B, mixing the component A and the component B according to the weight ratio of 1 (1.7-2), and foaming and molding by a high-pressure foaming machine. Preferably, in step S1, the injection pressure of the liquid carbon dioxide is 5-15 MPa, and the material temperature is controlled at 20-40 ℃. More preferably, in step S1, the injection pressure of the liquid carbon dioxide is 7.5-15 MPa, and the material temperature is controlled at 32-40 ℃. The critical pressure of carbon dioxide was 7.3MPa and the critical temperature was 31 ℃. When the pressure is more than 7.3MPa and the temperature is more than the critical temperature, the carbon dioxide is in a supercritical state, has the density similar to that of liquid and the diffusivity similar to that of gas, can instantaneously form a homogeneous solution with the polyol, and has extremely high mixing quality. Preferably, in the step S1, the component A comprises, by weight, 20-40 parts of polyester polyol, 10-30 parts of polyether polyol, 1-3 parts of foaming catalyst, 1-3 parts of foam stabilizer, 1-3 parts of chemical foaming agent and 3-10 parts of liquid carbon dioxide. The polyester polyol and isocyanate have high reactivity to form polyurethane ester bonds, and the polyether polyol is used for adjusting the viscosity of a system, improving the compatibility and fluidity of raw materials and reducing the brittleness of foam. The foaming catalyst is used for precisely regulating and controlling the balance of the foaming reaction and the gel reaction, and ensuring that the foam rises well and is stable. The foam stabilizer is used for stabilizing the cell structure and preventing foam combination and collapse, and is a decisive auxiliary agent for realizing high closed porosity. Preferably, the chemical foaming agent is deionized water. Preferably, the foam stabilizer is a polysiloxane-polyether copolymer. The siloxane chain segment (hydrophobic) can strongly reduce the surface tension, and the polyether chain segment (hydrophilic) can ensure that the siloxane chain segment is well dispersed in a polyol/water system, so that bubbles are uniformly nucleated, and an elastic film is formed on the wall of the bubbles. Preferably, the foaming catalyst is a trimerization catalyst or an organometallic salt catalyst. The trimerization catalyst can be PC-41, which can strongly catalyze isocyanate to trimerize to form isocyanurate ring, and the organic metal salt catalyst can be potassium acetate, which can promote polymer network to form rapidly, stabilize cells and prevent foam collapse after