WO2016150016A1

WO2016150016A1 - Polyurethane composition, polyurethane foam and preparation method therefor and fridge

Info

Publication number: WO2016150016A1
Application number: PCT/CN2015/081692
Authority: WO
Inventors: 赵士虎; 李彩侠; 程发祥; 琚绍成; 朱洪阳; 张静静
Original assignee: 合肥华凌股份有限公司; 美的集团股份有限公司
Priority date: 2015-03-24
Filing date: 2015-06-17
Publication date: 2016-09-29
Also published as: CN104672426A; CN104672426B

Abstract

Provided are a polyurethane composition, a polyurethane foam and a preparation method therefor, and a fridge. The polyurethane composition comprises: 25-60 parts by weight of a sorbitol polyether polyol, 15-40 parts by weight of a composite polyether polyol, 3-30 parts by weight of a diphenylmethane diamine polyether polyol, 3-15 parts by weight of a glycerin polyether polyol, 3-20 parts by weight of an aromatic polyester polyol, 0-5 parts by weight of a composite crosslinking agent, 1-55 parts by weight of a foaming agent, 1.0-5.0 parts by weight of a foam stabilizer, 0.5-2.0 parts by weight of water, 1.0-3.5 parts by weight of a composite catalyst, and 120-160 parts by weight of an isocyanate, wherein the index of the isocyanate is 0.95-1.10.

Description

Polyurethane composition, polyurethane foam, preparation method thereof and refrigerator

Priority information

Priority is claimed on Japanese Patent Application No. 201510130859.9, the entire disclosure of which is incorporated herein by reference.

Technical field

The invention belongs to the technical field of refrigerators, and in particular to a polyurethane composition, a polyurethane foam, a preparation method thereof and a refrigerator.

Background technique

At present, the state is paying more and more attention to energy conservation and environmental protection, resulting in the fourth generation of new environmentally-friendly and high-efficiency foaming agent - trans-1-chloro-3,3,3-trifluoropropene (hereinafter referred to as LBA), but LBA It has strong corrosiveness to the inner tank of the refrigerator. After high and low temperature test, the inner liner will be corroded and cracked. In order to solve this problem, in actual production, a HIPS/PE alloy liner was invented. However, the surface of the alloy liner has a low surface polarity and a small adhesion to the foamed material. Because the adhesion of the rigid polyurethane foam is related to the foam density, the lower the density, the worse the adhesion. In the polyurethane composition using LBA as a foaming agent, in order to meet the demand of low manufacturing cost, the foam density prepared is small, generally between 30.5 and 32 kg/m ³ , so that the foam and the inner liner of the refrigerator are less adhesive. In addition, since the HIPS/PE alloy liner uses a large amount of low-boiling foaming agent, after foaming, the foaming agent volatilizes, taking away the heat of the foam surface, thereby reducing the adhesion of the foam to the surface of the liner. Therefore, after the HIPS/PE alloy liner is foamed or after the high and low temperature test, the foamed layer is easily debonded from the liner. In order to solve this problem, the measures that can be taken include: performing secondary corona on the one hand and increasing the corona value of the plate, but the secondary corona will increase the cost, increase the working hours, and reduce the production efficiency of the refrigerator liner and the refrigerator; In terms of reducing the PE content and increasing the polarity of the liner, the thickness of the foamed alloy layer produced by this measure is uneven, and there may be no phenomenon of alloy layer locally, which does not achieve the anti-corrosion effect; on the other hand, the foam density is increased because Adhesion is affected by the density of the foam, and the greater the density, the better the adhesion. But this kind of measure will increase the cost of the refrigerator.

Therefore, how to design a foam material with low density, low cost and good bonding performance and a refrigerator having the same has become an urgent problem to be solved.

Summary of the invention

The present invention aims to solve at least one of the technical problems in the related art to some extent. To this end, an object of the present invention is to provide a polyurethane composition, a polyurethane foam, a preparation method thereof and a refrigerator using the polyurethane composition The resulting polyurethane foam has a low density and good bonding properties, and is also low in production cost.

In one aspect of the invention, the invention proposes a polyurethane composition. According to an embodiment of the invention, the polyurethane composition comprises:

25 to 60 parts by weight of sorbitol polyether polyol;

15 to 40 parts by weight of the composite polyether polyol;

3 to 30 parts by weight of diphenylmethanediamine polyether polyol;

3 to 15 parts by weight of a glycerin polyether polyol;

3 to 20 parts by weight of an aromatic polyester polyol;

0 to 5 parts by weight of a composite crosslinking agent;

1 to 55 parts by weight of a foaming agent;

1.0 to 5.0 parts by weight of a foam stabilizer;

0.5 to 2.0 parts by weight of water;

1.0 to 3.5 parts by weight of the composite catalyst;

120 to 160 parts by weight of isocyanate,

Wherein the isocyanate has an index of from 0.95 to 1.10.

Thus, the polyurethane foam obtained by using the polyurethane composition according to the embodiment of the present invention has a low density and good bonding property, and is also low in production cost.

Further, the polyurethane composition according to the above embodiment of the present invention may further have the following additional technical features:

In some embodiments of the invention, the polyurethane composition comprises: 25 to 50 parts by weight of the sorbitol polyol; 15 to 30 parts by weight of the composite polyether polyol; 5 to 25 parts by weight The diphenylmethanediamine polyether polyol; 3 to 10 parts by weight of the glycerin polyether polyol; 5 to 15 parts by weight of the aromatic polyester polyol; 2 to 4 parts by weight The composite crosslinking agent; 1 to 55 parts by weight of the blowing agent; 1.0 to 5.0 parts by weight of the foam stabilizer; 1.2 to 1.9 parts by weight of the water; 1.0 to 3.5 parts by weight of the composite catalyst And 120 to 160 parts by weight of the isocyanate. Thereby, the density and production cost of the obtained polyurethane foam can be further reduced while improving the bonding property.

In some embodiments of the present invention, the sorbitol polyol has a hydroxyl value of 380 to 470 mgKOH/g, and the sorbitol polyol has a viscosity of 8000 to 15000 mPa·s, the sorbitol. The polyol has a functionality of 6. Thereby, not only the strength of the obtained polyurethane foam can be improved, but also the thermal conductivity of the obtained polyurethane foam can be remarkably lowered.

In some embodiments of the present invention, the composite polyether polyol is polymerized from sucrose, triethanolamine, and propylene oxide, wherein a weight ratio of the sucrose to the triethanolamine is from 1 to 4:1. The complex polyether polyol has a functionality of 4-6, the complex polyether polyol has a hydroxyl value of 360-420 mgKOH/g, and the composite polyether polyol has a viscosity of 5000-14000 mPa·s. Thereby, the adhesive property of the obtained polyurethane foam can be remarkably improved.

In some embodiments of the invention, the diphenylmethanediamine polyether polyol is oxidized by diphenylmethanediamine a polymerization of propylene and ethylene oxide, wherein the weight ratio of the propylene oxide to the ethylene oxide is 1-4:1, and the hydroxyl value of the diphenylmethanediamine polyether polyol is 380-440 mgKOH/g. The viscosity of the diphenylmethanediamine polyether polyol is 15,000 to 25,000 mPa·s. Thereby, the strength and mold release property of the obtained polyurethane foam can be remarkably improved, and at the same time, the adhesive property can be improved.

In some embodiments of the invention, the glycerol polyether polyol has a hydroxyl value of from 160 to 300 mgKOH/g, and the glycerol polyether polyol has a viscosity of from 200 to 600 mPa·s. Thereby, the adhesive property of the obtained polyurethane foam can be further improved.

In some embodiments of the present invention, the aromatic polyester polyol has a hydroxyl value of 200 to 350 mgKOH/g, and the aromatic polyester polyol has a viscosity of 1000 to 2000 mPa·s, the aromatic polyester. The polyol has a functionality of 2.7. Thereby, the adhesive property of the polyurethane foam can be further improved.

In some embodiments of the invention, the aromatic polyester polyol is a phthalic anhydride polyester. Thereby, the adhesive property of the polyurethane foam can be further improved.

In some embodiments of the invention, the blowing agent comprises trans-1-chloro-3,3,3-trifluoropropene, wherein the trans-1-chloro-3,3,3-tri The amount of fluoropropene used is from 1 to 55 parts by weight. Thereby, the heat insulating property of the polyurethane foam is further improved while significantly reducing the density of the obtained polyurethane foam.

In some embodiments of the present invention, the blowing agent further comprises at least one of cyclopentane and pentafluoropropane, wherein the cyclopentane is used in an amount of 0 to 15 parts by weight, the pentafluoropropane The amount used is 0 to 20 parts by weight. Thereby, the foam production cost can be reduced.

In some embodiments of the invention, the composite catalyst comprises pentamethyldiethylenetriamine, bis-dimethylaminoethyl ether, N-methyldicyclohexylamine, and tetramethylhexamethylenediamine, dimethyl At least one of a cyclic amine, 1,2-dimethylimidazole, and dimethylbenzylamine, ammonium trimethylformate, a quaternary ammonium salt, and a quaternary ammonium salt. Thereby, the adhesive property of the polyurethane foam can be further improved.

In some embodiments of the invention, the foam stabilizer is a silicone oil. Thereby, the adhesive property of the polyurethane foam can be further improved.

In some embodiments of the invention, the complex crosslinking agent comprises ethylene glycol, propylene glycol, diethylene glycol, glycerin, trimethylolpropane, pentaerythritol, triethanolamine, ethylenediamine, and diphenylmethanediamine. At least two of them. Thereby, the adhesive property of the polyurethane foam can be further improved.

In some embodiments of the invention, the isocyanate is a polymethylpolyphenyl polyisocyanate. Thereby, the adhesive property of the polyurethane foam can be further improved.

In a second aspect of the invention, the invention proposes a polyurethane foam. According to an embodiment of the invention, the polyurethane foam is made from the polyurethane composition described above. Thus, by using the above-described polyurethane composition, the obtained polyurethane foam can be made to have a low density, good adhesion property, and low production cost.

Further, the polyurethane foam according to the above embodiment of the present invention may further have the following additional technical features:

In some embodiments of the invention, the polyurethane foam has a density of less than 28.5 kg/m ³ .

In some embodiments of the invention, the polyurethane foam has a thermal conductivity of less than 17.5 mW/m·k.

In some embodiments of the invention, the polyurethane foam has a compressive strength greater than 150 kPa.

In some embodiments of the invention, the polyurethane foam has a bond strength greater than 280 kPa.

In a third aspect of the invention, the invention proposes a refrigerator. According to an embodiment of the invention, the refrigerator comprises the polyurethane foam described above. Thus, by using the above-mentioned polyurethane foam, the refrigerator has the characteristics of good heat preservation effect and low energy consumption.

In a fourth aspect of the invention, the invention provides a process for the preparation of the polyurethane foam described above. According to an embodiment of the invention, the method comprises:

Providing a premix comprising a sorbitol polyol, a composite polyether polyol, a diphenylmethane diamine polyether polyol, a glycerin polyether polyol, an aromatic polyester polyol, a composite blend a binder, a blowing agent, a foam stabilizer, water, and a composite catalyst;

The premix and isocyanate are injected into a mold for aging treatment to obtain the polyurethane foam.

According to the method for preparing a polyurethane foam according to an embodiment of the present invention, the above-mentioned polyurethane foam having low density, good bonding property and low production cost can be prepared, and by using a low vapor phase thermal conductivity, a low GWP, and a zero ODP foaming agent, not only can Meet energy-saving requirements, and be environmentally friendly and green.

Further, the method for producing a polyurethane foam according to the above embodiment of the present invention may further have the following additional technical features:

In some embodiments of the invention, a refrigerator liner having a predetermined shape is disposed in the mold.

In some embodiments of the invention, the mold is a refrigerator cavity.

In some embodiments of the invention, the mold has a temperature of 38 to 45 °C.

In some embodiments of the invention, the preset pressure is 130 to 150 bar.

In some embodiments of the invention, the predetermined time is 178-181 s.

According to still another embodiment of the present invention, the present invention provides a polyurethane composition.

According to still another embodiment of the present invention, the present invention provides a polyurethane foam and a method of preparing the same.

In still another embodiment of the present invention, the present invention provides a refrigerator having a polyurethane foam prepared by the above-described method for preparing a polyurethane foam.

In order to achieve the above object, according to an embodiment of the first aspect of the present invention, there is proposed a polyurethane composition which is prepared by the following raw materials in a ratio by weight: sorbitol polyether 25 to 60 parts by weight 15 to 40 parts by weight of the composite polyether polyol, 3 to 30 parts by weight of the diphenylmethanediamine polyether polyol, 3 to 15 parts by weight of the glycerin polyether polyol, and 3 to 20 parts by weight of the aromatic polyester polyol. 0 to 5 parts by weight of the composite crosslinking agent, 1 to 55 parts by weight of the foaming agent, 1.0 to 5.0 parts by weight of the foam stabilizer, 0.5 to 2.0 parts by weight of water, 1.0 to 3.5 parts by weight of the composite catalyst, and isocyanate 120 to 160 Parts by weight; wherein the isocyanate has an index of from 0.95 to 1.10.

According to an embodiment of the present invention, the sorbitol polyol is polymerized from sorbitol and propylene oxide, and the sorbitol is an initiator, wherein the sorbitol polyol is 25 to 50 parts by weight, The sorbitol polyether polyol has a hydroxyl value of 380 to 470 mgKOH/g, the sorbitol polyether polyol has a viscosity of 8000 to 15000 mPa·s, and the sorbitol polyether polyol has a functionality of 6; The composite polyether polyol is formed by polymerizing sucrose, triethanolamine and the propylene oxide, and the sucrose and the triethanolamine are starting materials, wherein the composite polyether polyol is 15 to 30 parts by weight, The weight ratio of sucrose to the triethanolamine is from 1 to 4:1, the functionality of the composite polyether polyol is from 4 to 6, and the hydroxyl value of the composite polyether polyol is from 360 to 420 mgKOH/g. The viscosity of the ether polyol is 5,000 to 12,000 mPa·s; the diphenylmethane diamine polyether polyol is formed by polymerizing diphenylmethane diamine, the propylene oxide and ethylene oxide, the diphenylmethane The amine is a starter, wherein the diphenylmethanediamine polyether polyol is 5 to 25 heavy The weight ratio of the propylene oxide to the ethylene oxide is 1-4:1, and the hydroxyl value of the diphenylmethanediamine polyether polyol is 380-440 mgKOH/g, the diphenylmethanediamine The polyether polyol has a viscosity of 15000 to 25000 mPa·s; the glycerin polyether polyol is formed by polymerizing glycerin and the propylene oxide, and the glycerin is a starter, wherein the glycerol polyether polyol 3 to 10 The glycerol polyether polyol has a hydroxyl value of 160 to 300 mgKOH/g, the glycerin polyether polyol has a viscosity of 200 to 600 mPa·s, and the aromatic polyester polyol is a phthalic anhydride polyester, wherein 5 to 15 parts by weight of the aromatic polyester polyol, the aromatic polyester polyol has a hydroxyl value of 200 to 350 mgKOH/g, and the aromatic polyester polyol has a viscosity of 1000 to 2000 mPa·s, and the aromatic The functionality of the polyester polyol is 2.7; the blowing agent consists of trans-1-chloro-3,3,3-trifluoropropene or from the trans-1-chloro-3,3,3-tri a mixture of fluoropropene and cyclopentane and/or pentafluoropropane, wherein the trans-1-chloro-3,3,3-trifluoropropene is 1 to 55 parts by weight, and the cyclopentane is 0 to 15 parts by weight. The five 0 to 20 parts by weight of fluoropropane; the composite catalyst is composed of pentamethyldiethylenetriamine, bis-dimethylaminoethyl ether, N-methyldicyclohexylamine, tetramethylhexamethylenediamine, dimethyl One or more constituents of cyclohexylamine, 1,2-dimethylimidazole and dimethylbenzylamine, ammonium trimethylformate, ethyl quaternary ammonium salt and quaternary ammonium salt; the foam stabilizer is Si- a C-structured silicone oil; the composite crosslinking agent is composed of ethylene glycol, propylene glycol, diethylene glycol, glycerin, trimethylolpropane, pentaerythritol, triethanolamine, ethylenediamine, diphenylmethanediamine; The water is 1.2 to 1.9 parts by weight; the organic isocyanate is a plurality of primary polyphenyl polyisocyanates.

The polyurethane composition provided by the embodiment of the invention has low viscosity, mild reaction speed, good fluidity and adhesion; wherein the sorbitol polyol uses sorbitol as a starting agent, not only can improve the strength of the foam, The prepared foam cells are fine and can reduce the thermal conductivity of the foam; the composite polyether polyol has the characteristics of high-functionality polyether and amine-based polyether, and the prepared foam has high strength and reacts with organic isocyanate. It has high activity and fast curing speed after foaming, effectively improves the shortness of the foam skin and is easy to crisp, and improves the bonding strength; while the diphenylmethanediamine polyether polyol is composed of diphenylmethanediamine. It is an initiator, polymerized with propylene oxide and ethylene oxide, wherein the diphenylmethanediamine is an amine-based polyether and contains two benzene rings in the molecule, which greatly improves the strength of the polyurethane itself, and Ether polyols can be used together to increase the strength and release of the foam while improving the bonding properties; The glycerin polyether polyol is added to the polyurethane composition because the glycerin polyether polyol has good fluidity, which is advantageous for improving the adhesion, but the amount cannot be too much, and if it is too much, the strength of the foam is affected. Preferably, The glycerin polyether polyol is 3 to 10 parts by weight; wherein the aromatic polyester polyol in the polyurethane composition contains a benzene ring, which can improve the strength of the foam, lower the thermal conductivity of the foam, and has a small viscosity and good fluidity. It is advantageous to improve the adhesion of the foam, but because the functionality is small, the amount is not excessive, and preferably, the aromatic polyester polyol is preferably used in an amount of 5 to 15 parts by weight; wherein the composite crosslinking of the polyurethane composition The agent can meet the foam performance requirements and increase the bond strength of the foam. In a preferred embodiment of the invention, a mixture of 2 or 3 functional groups and a 4 functional crosslinker is preferred, and the composite crosslinker is used in an amount of 0 to 5 parts by weight. In a specific embodiment, the composite crosslinking agent is preferably a mixture of glycerin and ethylenediamine in a weight ratio of 1:1, preferably in an amount of 2 to 4 parts by weight; in the polyurethane composition, the proportion of water is also very important. Excessive water or too little water will make the surface of the foam crisp and affect the bonding strength. If the water is too small, in order to ensure the fluidity of the foam and the low density of the foam, the amount of the physical foaming agent is large, and when foaming, As the vaporization of the physical blowing agent will take away a large amount of heat of reaction, affecting the ripening performance; if the water is too much, the water reacts with the isocyanate to produce a large amount of allophanate, resulting in a crisp surface of the foam and affecting the bond strength. The physical foaming agent and the chemical foaming agent and water should be controlled within a proper ratio range, so that the combined polyether has a moderate viscosity, and the heat generated by the reaction of water and isocyanate can make up for the heat taken away by the vaporization of the physical foaming agent, thereby increasing the foam. The effect of bonding strength. Among them, the amount of water used is preferably from 1.2 to 1.9 parts by weight.

According to an embodiment of the second aspect of the invention, a polyurethane foam is proposed, wherein the polyurethane foam is made of the polyurethane composition described above.

According to an embodiment of the invention, the polyurethane foam has a density of less than 28.5 kg/m ³ .

According to an embodiment of the invention, the polyurethane foam has a thermal conductivity of less than 17.5 mW/m·k, the polyurethane foam has a compressive strength of more than 150 kPa, and the polyurethane foam has a bond strength of greater than 280 kPa.

The polyurethane foam provided according to the embodiment of the present invention is prepared by the polyurethane composition described above, wherein the polyurethane foam has a density of less than 28.5 kg/m ³ , a thermal conductivity of less than 17.5 mW/m·k, and a compressive strength of more than 150 kPa. The bond strength is greater than 280 kPa, so that the polyurethane foam has strong adhesiveness, and the foam and the liner do not detach after foaming or high and low temperature impact.

According to an embodiment of the third aspect of the present invention, there is provided a refrigerator comprising the polyurethane foam of any of the above embodiments.

The refrigerator provided according to the embodiment of the invention has good heat preservation effect and low energy consumption. Further, other refrigeration devices including the above polyurethane foam also have the advantageous effects of the above refrigerator.

According to an embodiment of the fourth aspect of the present invention, a method for producing a polyurethane foam is provided, comprising: mixing a sorbitol polyether polyol, a composite polyether polyol, and a diphenylmethane diamine polyether polyol by a stirring pressure tank; Alcohol, glycerin polyether polyol, aromatic polyester polyol, composite crosslinking agent, foaming agent, foam stabilizer, water, composite catalyst to obtain a premix; transfer the premix to a foaming machine by a pump The first working tank, making it the second work with the foaming machine The isocyanate in the can is injected into the mold having the vent hole at the top by a high pressure mixing head; the mixture of the premix in the mold and the isocyanate is aged for a predetermined time, and is formed after demolding The polyurethane foam; wherein the sorbitol polyether polyol is 25 to 60 parts by weight, the composite polyether polyol is 15 to 40 parts by weight, and the diphenylmethanediamine polyether polyol is 3 to 30 parts by weight. 3 parts by weight of the glycerin polyether polyol, 3 to 20 parts by weight of the aromatic polyester polyol, 0 to 5 parts by weight of the composite crosslinking agent, and 1 to 55 parts by weight of the foaming agent. And the foam stabilizer is 1.0 to 5.0 parts by weight, the water is 0.5 to 2.0 parts by weight, the composite catalyst is 1.0 to 3.5 parts by weight, the isocyanate is 120 to 160 parts by weight, and the isocyanate has an index of 0.95 to ～. 1.10.

According to an embodiment of the invention, the temperature of the mold is 38 to 45 ° C, the preset pressure is in the range of 130 to 150 bar, and the predetermined time is in the range of 178 to 181 s.

According to an embodiment of the present invention, the sorbitol polyether polyol, the composite polyether polyol, the diphenylmethanediamine polyether polyol, the glycerin polyether polyol, the aromatic polyester are mixed in the stirring pressure tank. Before the polyol, the composite crosslinking agent, the foaming agent, the foam stabilizer, the water, and the composite catalyst are obtained as a premix, the inner liner material of the refrigerator is cut into a sample piece and attached to the mold.

According to the preparation method provided by the embodiment of the present invention, the raw material used is the polyurethane composition described above, and the polyurethane foam prepared by the method has a small density of less than 28.5 kg/m ³ but has strong bonding. Sex, and after foaming or high and low temperature impact, the foam and the liner will not be separated; in addition, the polyurethane foam prepared by the method has a low thermal conductivity of less than 17.5 mW/m·k, high compressive strength and minimum compressive strength. More than 150Kpa.

It is worth noting that the polyurethane foam provided by the invention and the preparation method thereof adopt low-gas phase thermal conductivity, low GWP and zero ODP foaming agent, not only meet the energy-saving requirements, but also are environmentally friendly and environmentally friendly.

A method for producing a polyurethane foam according to an embodiment of the fifth aspect of the present invention, as shown in FIG. 1, the method comprising: step 102, mixing a sorbitol polyether polyol, a composite polyether polyol, and a second by a stirring pressure tank Phenylmethanediamine polyether polyol, glycerin polyether polyol, aromatic polyester polyol, composite crosslinking agent, foaming agent, foam stabilizer, water, composite catalyst to obtain a premix; step 104, The premix is transferred by a pump to a first working tank of the foaming machine, and the isocyanate in the second working tank of the foaming machine is injected into the top through a high pressure mixing head at a preset pressure. In the mold, step 106, aging the mixture of the premix and the isocyanate in the mold for a predetermined time to form the polyurethane foam after demolding; wherein the sorbitol polyol 25-60 Parts by weight, 15 to 40 parts by weight of the composite polyether polyol, 3 to 30 parts by weight of the diphenylmethanediamine polyether polyol, 3 to 15 parts by weight of the glycerin polyether polyol, and the fragrance Group polyester polyol 3~20 weight 0 to 5 parts by weight of the composite crosslinking agent, 1 to 55 parts by weight of the foaming agent, 1.0 to 5.0 parts by weight of the foam stabilizer, 0.5 to 2.0 parts by weight of the water, and 1.0 to 1.0 of the composite catalyst. 3.5 parts by weight, the isocyanate is 120 to 160 parts by weight, and the isocyanate has an index of 0.95 to 1.10.

According to the preparation method of the polyurethane foam provided by the embodiment of the present invention, the raw material used is the polyurethane described above The composition, the preparation method is different from the preparation method described above only in that the premix and the foamed isocyanate in the foaming machine are mixed by high pressure, and the injected cavity is different in type, and one is injected into the cavity of the polyurethane foam. Inside, the other is injected directly into the cavity of the refrigerator.

The additional aspects and advantages of the invention will be set forth in part in the description which follows.

DRAWINGS

The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from

1 is a schematic flow chart of a method for preparing a polyurethane foam according to an embodiment of the present invention;

2 is a schematic flow chart of a process for preparing a polyurethane foam according to still another embodiment of the present invention.

Detailed description of the invention

The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the drawings, wherein the same or similar reference numerals are used to refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are intended to be illustrative of the invention and are not to be construed as limiting.

In the first aspect of the invention. The present invention proposes a polyurethane composition. According to an embodiment of the present invention, the polyurethane polymer comprises: 25 to 60 parts by weight of a sorbitol polyol; 15 to 40 parts by weight of a composite polyether polyol; and 3 to 30 parts by weight of diphenylmethane diamine. a polyether polyol; 3 to 15 parts by weight of a glycerin polyether polyol; 3 to 20 parts by weight of an aromatic polyester polyol; 0 to 5 parts by weight of a composite crosslinking agent; and 1 to 55 parts by weight of a foaming agent 1.0 to 5.0 parts by weight of a foam stabilizer; 0.5 to 2.0 parts by weight of water; 1.0 to 3.5 parts by weight of a composite catalyst; and 120 to 160 parts by weight of an isocyanate, wherein the isocyanate has an index of from 0.95 to 1.10. The inventors have found that sorbitol polyol can not only improve the strength of the foam, but also the fineness of the prepared polyurethane foam, and also reduce the thermal conductivity of the polyurethane foam; the composite polyether polyol has both a high functionality polyether and The characteristics of the amino polyether make the obtained polyurethane foam have high strength, and have high activity in reacting with isocyanate, and at the same time, the curing speed after foaming is fast, effectively improving the shortcoming of the polyurethane foam skin, and thus Significantly improve the bonding performance; diphenylmethane diamine polyether polyol can significantly improve the strength and release of polyurethane foam, and at the same time improve its bonding properties; glycerol polyether polyol can effectively improve the flow of polyurethane composition To improve the bonding property of the obtained polyurethane foam, and the excessive use of the glycerin polyether polyol can significantly reduce the strength of the obtained polyurethane foam; the aromatic polyester polyol can significantly increase the strength of the polyurethane foam due to the presence of the benzene ring. And reduce its thermal conductivity, while the aromatic polyester polyol has a small viscosity and flows. Good, which is beneficial to improve the bonding performance of polyurethane foam; composite crosslinking agent can meet the performance requirements of polyurethane foam and improve its bonding performance; too much water or too little water will make the surface of the obtained polyurethane foam crisp. From However, if the water is too small, in order to ensure the fluidity of the foam and the low density of the foam, the amount of the physical foaming agent is large, and the vaporization of the physical foaming agent will take away a large amount of reaction heat during foaming, thereby affecting Curing performance, and if there is too much water, water reacts with isocyanate to produce a large amount of allophanate, which causes the surface of the foam to be crisp and affects the bond strength. Therefore, the physical foaming agent and chemical foaming agent and water need to be controlled at an appropriate ratio. In the range, the viscosity of the combined polyether is moderate, and the heat generated by the reaction of water and isocyanate can make up for the heat taken away by the vaporization of the physical foaming agent, thereby achieving the effect of improving the bonding strength of the foam. Thus, the polyurethane foam obtained by selecting the polyurethane composition of the formulation of the present invention has the characteristics of low density and good bonding property.

According to an embodiment of the present invention, the polyurethane composition comprises: 25 to 50 parts by weight of sorbitol polyol; 15 to 30 parts by weight of the composite polyether polyol; and 5 to 25 parts by weight of diphenylmethane diamine Polyether polyol; 3 to 10 parts by weight of glycerin polyether polyol; 5 to 15 parts by weight of aromatic polyester polyol; 2 to 4 parts by weight of composite crosslinking agent; 1 to 55 parts by weight of blowing agent 1.0 to 5.0 parts by weight of a foam stabilizer; 1.2 to 1.9 parts by weight of water; 1.0 to 3.5 parts by weight of a composite catalyst; and 120 to 160 parts by weight of an isocyanate. Thereby, the density and production cost of the obtained polyurethane foam can be further reduced while improving the bonding property.

According to still another embodiment of the present invention, the specific type of the sorbitol polyol is not particularly limited, and those skilled in the art can select according to actual needs. According to a specific embodiment of the present invention, the hydroxyl value can be selected to be 380 ～. 470 mg KOH/g, sorbitol polyether polyol having a viscosity of 8000 to 15000 mPa·s (25 ° C) and a functionality of 6. For example, a sorbitol polyol polymer obtained by polymerizing sorbitol as a starting agent and propylene oxide can be selected. The inventors have found that the sorbitol obtained by using sorbitol as a starting agent can not only significantly increase the strength of the polyurethane foam, but also the resulting polyurethane foam cells are more delicate, and the resulting polyurethane foam has a lower thermal conductivity.

According to still another embodiment of the present invention, the specific type of the composite polyether polyol is not particularly limited, and those skilled in the art can select according to actual needs. According to a specific embodiment of the present invention, the composite polyether polyol can be made from sucrose. And triethanolamine and propylene oxide are polymerized, wherein the weight ratio of sucrose to triethanolamine is 1-4:1, the functionality of the composite polyether polyol is 4-6, and the hydroxyl value of the composite polyether polyol is 360-420 mgKOH. /g, the composite polyether polyol has a viscosity of 5,000 to 12,000 mPa·s (25 ° C). The inventors have found that this type of composite polyether polyol can make the obtained polyurethane foam have higher strength, and has higher activity in reaction with isocyanate, and at the same time, the curing speed after foaming is fast, and the polyurethane foam skin is effectively improved. It is easy to crispy, which further improves its bonding performance.

According to still another embodiment of the present invention, the specific type of the diphenylmethanediamine polyether polyol is not particularly limited, and those skilled in the art may select according to actual needs. According to a specific embodiment of the present invention, diphenylmethane The diamine polyether polyol can be polymerized from diphenylmethanediamine, propylene oxide and ethylene oxide, wherein the weight ratio of propylene oxide to ethylene oxide is from 1 to 4:1, and diphenylmethanediamine polyether polyol The hydroxyl value is 380 to 440 mgKOH/g, and the viscosity of the diphenylmethanediamine polyether polyol is 15,000 to 25,000 mPa·s (25 ° C). The inventors have found that diphenylmethanediamine can significantly increase the strength of the resulting polyurethane foam by using two benzene rings in the molecule, and is used together with a polyether polyol. The strength and mold release property of the polyurethane foam can be remarkably improved while further improving the bonding property.

According to still another embodiment of the present invention, the specific type of the glycerin polyether polyol is not particularly limited, and those skilled in the art can select according to actual needs. According to a specific embodiment of the present invention, the hydroxyl value can be selected from 160 to 300 mg KOH. / g, a glycerin polyether polyol having a viscosity of 200 to 600 mPa·s (25 ° C). The inventors have found that this type of polyether polyol has a higher fluidity, thereby further improving the bonding properties of the resulting polyurethane foam.

According to still another embodiment of the present invention, the specific type of the aromatic polyester polyol is not particularly limited, and those skilled in the art can select according to actual needs. According to a specific embodiment of the present invention, the hydroxyl value can be selected to be 200- 350 mg KOH/g, an aromatic polyester polyol having a viscosity of 1000 to 2000 mPa·s and a functionality of 2.7. The inventors have found that this type of aromatic polyester polyol can significantly increase the strength of the polyurethane foam, and can significantly reduce the thermal conductivity of the resulting polyurethane foam, while having a small viscosity and high fluidity, thereby further improving the resulting polyurethane foam. Bonding performance. According to a specific example of the invention, the aromatic polyester polyol is a phthalic anhydride polyester.

According to still another embodiment of the present invention, the specific type of the foaming agent is not particularly limited, and those skilled in the art may select according to actual needs. According to a specific embodiment of the present invention, the foaming agent may include trans-1- Chloro-3,3,3-trifluoropropene, wherein trans-1-chloro-3,3,3-trifluoropropene is used in an amount of from 1 to 55 parts by weight. Thereby, the density of the obtained polyurethane foam can be further reduced.

According to still another embodiment of the present invention, the blowing agent may further include at least one of cyclopentane and pentafluoropropane, wherein the amount of the cyclopentane is 0 to 15 parts by weight, and the amount of the pentafluoropropane is 0 to 20 parts by weight. Thereby, the density of the obtained polyurethane foam can be further reduced.

According to still another embodiment of the present invention, the specific type of the composite catalyst is not particularly limited, and those skilled in the art can select according to actual needs. According to a specific embodiment of the present invention, the composite catalyst may be selected from the group consisting of pentamethyldivinylene. Triamine, bis-dimethylaminoethyl ether, N-methyldicyclohexylamine and tetramethylhexamethylenediamine, dimethylcyclohexylamine, 1,2-dimethylimidazole and dimethylbenzylamine At least one of ammonium trimethylformate, ethyl quaternary ammonium salt and octaquat ammonium salt. The inventors have found that this type of composite catalyst can significantly increase the ripening efficiency of the polyurethane composition.

According to still another embodiment of the present invention, the specific type of the foam stabilizer is not particularly limited, and those skilled in the art can select according to actual needs. According to a specific embodiment of the present invention, the foam stabilizer may be a silicone oil. The inventors have found that the use of silicone oil as a foam stabilizer can significantly promote the formation of polyurethane foam in the polyurethane foaming process, and the resulting polyurethane foam cells are fine, thereby effectively preventing foam collapse.

According to still another embodiment of the present invention, the specific type of the composite crosslinking agent is not particularly limited, and those skilled in the art can select according to actual needs. According to a specific embodiment of the present invention, the composite crosslinking agent may be selected from the group consisting of At least two of diol, propylene glycol, diethylene glycol, glycerin, trimethylolpropane, pentaerythritol, triethanolamine, ethylenediamine and diphenylmethanediamine, preferably a mixture of glycerin and ethylenediamine, according to the present invention As a specific example of the invention, the mass ratio of glycerin to ethylenediamine may be 1:1. The inventors have found that this type of composite crosslinker can give the resulting polyurethane foam a density Low and good bonding properties.

According to still another embodiment of the present invention, the specific type of isocyanate is not particularly limited, and those skilled in the art can select according to actual needs. According to a specific embodiment of the present invention, the isocyanate may be a polymethylpolyphenyl polyisocyanate. . Thus, the isocyanate can significantly improve the bonding properties of the polyurethane foam.

In a second aspect of the invention, the invention proposes a polyurethane foam. According to an embodiment of the invention, the polyurethane foam is made from the polyurethane composition described above. Thus, by using the above-described polyurethane composition, the obtained polyurethane foam can be made to have a low density, good adhesion property, and low production cost. It should be noted that the advantages and features described above for the polyurethane composition are equally applicable to the polyurethane foam, and are not described herein again.

According to one embodiment of the invention, the polyurethane foam has a density of less than 28.5 kg/m ³ .

According to still another embodiment of the present invention, the polyurethane foam has a thermal conductivity of less than 17.5 mW/m·k.

According to still another embodiment of the present invention, the polyurethane foam has a compressive strength of more than 150 kPa.

According to still another embodiment of the present invention, the polyurethane foam has a bond strength of more than 280 kPa.

The polyurethane foam according to the embodiment of the present invention is prepared by using the polyurethane composition described above to have a density of less than 28.5 kg/m 3 , a thermal conductivity of less than 17.5 mW/m·k, a compressive strength of more than 150 kPa, and a bonding strength greater than 280 kPa, thereby making the polyurethane foam have strong adhesion, and the foam and the liner do not detach after foaming or high and low temperature impact.

In a third aspect of the invention, the invention proposes a refrigerator. According to an embodiment of the invention, the refrigerator comprises the polyurethane foam described above. Thus, by using the above-mentioned polyurethane foam, the refrigerator has the characteristics of good heat preservation effect and low energy consumption. It should be noted that the features and advantages described above for the polyurethane foam are also applicable to the refrigerator, and are not described herein again.

In a fourth aspect of the invention, the invention provides a method of making a polyurethane foam. According to an embodiment of the invention, the method comprises: providing a premix comprising a sorbitol polyol, a composite polyether polyol, a diphenylmethanediamine polyether polyol, a glycerol polyether polyol An alcohol, an aromatic polyester polyol, a composite crosslinking agent, a blowing agent, a foam stabilizer, water, and a composite catalyst; and injecting the premix and the isocyanate into a mold for aging treatment to obtain the polyurethane foam . The inventors have found that the method can prepare the above-mentioned polyurethane foam having low density, good bonding property and low production cost, and can not only meet the energy saving requirement by adopting low gas phase thermal conductivity, low GWP and zero ODP foaming agent, and Environmentally friendly and green.

A method of preparing a polyurethane foam according to an embodiment of the present invention will now be described in detail with reference to FIG. According to an embodiment of the invention, the method comprises:

S100: Provide premix

According to an embodiment of the present invention, the premix comprises a sorbitol polyol, a composite polyether polyol, a diphenylmethane diamine polyether polyol, a glycerin polyether polyol, an aromatic polyester polyol, a composite cross Coupling agent, foaming agent, foam stabilization Agent, water and composite catalyst. Specifically, the sorbitol polyether polyol, the composite polyether polyol, the diphenylmethane diamine polyether polyol, the glycerin polyether polyol, the aromatic polyester polyol, and the composite crosslinking agent can be mixed by stirring the pressure tank. , a blowing agent, a foam stabilizer, water and a composite catalyst, so that a premix can be obtained.

According to an embodiment of the present invention, the premix comprises 25 to 60 parts by weight of sorbitol polyhydric alcohol; 15 to 40 parts by weight of the composite polyether polyol; and 3 to 30 parts by weight of diphenylmethane diamine. Ether polyol; 3 to 15 parts by weight of glycerin polyether polyol; 3 to 20 parts by weight of aromatic polyester polyol; 0 to 5 parts by weight of a composite crosslinking agent; 1 to 55 parts by weight of a foaming agent; 1.0 to 5.0 parts by weight of a foam stabilizer; 0.5 to 2.0 parts by weight of water and 1.0 to 3.5 parts by weight of a composite catalyst. The inventors have found that sorbitol polyol can not only improve the strength of the foam, but also the fineness of the prepared polyurethane foam, and also reduce the thermal conductivity of the polyurethane foam; the composite polyether polyol has both a high functionality polyether and The characteristics of the amino polyether make the obtained polyurethane foam have high strength, and have high activity in reacting with isocyanate, and at the same time, the curing speed after foaming is fast, effectively improving the shortcoming of the polyurethane foam skin, and thus Significantly improve the bonding performance; diphenylmethane diamine polyether polyol can significantly improve the strength and release of polyurethane foam, and at the same time improve its bonding properties; glycerol polyether polyol can effectively improve the flow of polyurethane composition To improve the bonding property of the obtained polyurethane foam, and the excessive use of the glycerin polyether polyol can significantly reduce the strength of the obtained polyurethane foam; the aromatic polyester polyol can significantly increase the strength of the polyurethane foam due to the presence of the benzene ring. And reduce its thermal conductivity, while the aromatic polyester polyol has a small viscosity and flows. Good, which is beneficial to improve the bonding performance of polyurethane foam; composite crosslinking agent can meet the performance requirements of polyurethane foam and improve its bonding performance; too much water or too little water will make the surface of the obtained polyurethane foam crisp. Therefore, the bonding performance is affected. If the water is too small, in order to ensure the fluidity of the foam and the low density of the foam, the amount of the physical foaming agent is large, and the vaporization of the physical foaming agent during the foaming will take away a large amount of reaction heat, thereby affecting Curing performance, and if there is too much water, water reacts with isocyanate to produce a large amount of allophanate, which causes the surface of the foam to be crisp and affects the bond strength. Therefore, the physical foaming agent and chemical foaming agent and water need to be controlled at an appropriate ratio. In the range, the viscosity of the combined polyether is moderate, and the heat generated by the reaction of water and isocyanate can make up for the heat taken away by the vaporization of the physical foaming agent, thereby achieving the effect of improving the bonding strength of the foam. Thus, the polyurethane foam obtained by selecting the premix of the composition of the present invention has the characteristics of low density and good bonding property.

According to an embodiment of the present invention, the premix comprises: 25 to 50 parts by weight of sorbitol polyhydric alcohol; 15 to 30 parts by weight of the composite polyether polyol; and 5 to 25 parts by weight of diphenylmethane diamine Polyether polyol; 3 to 10 parts by weight of glycerin polyether polyol; 5 to 15 parts by weight of aromatic polyester polyol; 2 to 4 parts by weight of composite crosslinking agent; 1 to 55 parts by weight of blowing agent 1.0 to 5.0 parts by weight of a foam stabilizer; 1.2 to 1.9 parts by weight of water and 1.0 to 3.5 parts by weight of a composite catalyst. Thereby, the density and production cost of the obtained polyurethane foam can be further improved while improving the bonding property.

According to still another embodiment of the present invention, the specific type of the diphenylmethanediamine polyether polyol is not particularly limited, and those skilled in the art may select according to actual needs. According to a specific embodiment of the present invention, diphenylmethane The diamine polyether polyol can be polymerized from diphenylmethanediamine, propylene oxide and ethylene oxide, wherein the weight ratio of propylene oxide to ethylene oxide is from 1 to 4:1, and diphenylmethanediamine polyether polyol The hydroxyl value is 380 to 440 mgKOH/g, and the viscosity of the diphenylmethanediamine polyether polyol is 15,000 to 25,000 mPa·s (25 ° C). The inventors have found that diphenylmethanediamine can significantly increase the strength of the resulting polyurethane foam by containing two benzene rings in the molecule, and can be used together with the polyether polyol to significantly increase the strength and release property of the polyurethane foam. At the same time, the bonding performance is further improved.

According to still another embodiment of the present invention, the blowing agent may further include at least one of cyclopentane and pentafluoropropane. The cyclopentane is used in an amount of 0 to 15 parts by weight, and the pentafluoropropane is used in an amount of 0 to 20 parts by weight. Thereby, the density of the obtained polyurethane foam can be further reduced.

According to still another embodiment of the present invention, the specific type of the composite crosslinking agent is not particularly limited, and those skilled in the art can select according to actual needs. According to a specific embodiment of the present invention, the composite crosslinking agent may be selected from the group consisting of At least two of diol, propylene glycol, diethylene glycol, glycerin, trimethylolpropane, pentaerythritol, triethanolamine, ethylenediamine and diphenylmethanediamine, preferably a mixture of glycerin and ethylenediamine, according to the present invention As a specific example of the invention, the mass ratio of glycerin to ethylenediamine may be 1:1. The inventors have found that this type of composite crosslinking agent can provide the resulting polyurethane foam with low density and good bonding properties.

S200: injecting the premix and the isocyanate into the mold for curing

According to an embodiment of the present invention, the premix and the isocyanate are injected into a mold for aging treatment, whereby a polyurethane foam can be obtained. Specifically, the premix is transferred to the first working tank of the foaming machine by a pump, the isocyanate is injected into the second working tank of the foaming machine, and then the premix is mixed under a preset pressure by a high pressure mixing head. The isocyanate is injected into a mold having a vent hole at the top, and then the premix and the isocyanate in the mold are aged for a predetermined time and then released to obtain a polyurethane foam.

According to an embodiment of the present invention, the isocyanate may be used in an amount of from 120 to 160 parts by weight, wherein the isocyanate has an index of from 0.95 to 1.10. According to still another embodiment of the present invention, the specific type of isocyanate is not particularly limited, and those skilled in the art can select according to actual needs. According to a specific embodiment of the present invention, the isocyanate may be a polymethylpolyphenyl polyisocyanate. . Thus, the isocyanate can significantly improve the bonding properties of the polyurethane foam.

According to an embodiment of the present invention, the mold may be a mold provided with a predetermined shape of the refrigerator liner, specifically, the refrigerator liner material is cut into a sample piece, and then the sample piece is pasted in the mold, or the mold may be The cavity of the refrigerator.

According to still another embodiment of the present invention, the temperature of the mold may be 38 to 45 ° C, preferably 40 ° C, the preset pressure is 130 to 150 bar, and the predetermined time is 178 to 181 s.

The polyurethane foam obtained by the method for preparing a polyurethane foam according to an embodiment of the present invention has a small density (density of less than 28.5 kg/m ³ ), but has strong adhesiveness, and after foaming or high and low temperature impact, the foam and the foam The inner liner does not detach, and the polyurethane foam prepared by the method has low thermal conductivity (thermal conductivity less than 17.5 mW/m·k) and high compressive strength (minimum compressive strength is greater than 150 Kpa).

The invention is described below with reference to the specific embodiments, which are intended to be illustrative, and not to limit the invention in any way.

Example 1

Raw material formula: 40 parts by weight of sorbitol polyether polyol, 21.4 parts by weight of composite polyether polyol, 15 parts by weight of diphenylmethane diamine polyether polyol, 5 parts by weight of glycerol polyether polyol, 10 Parts by weight of aromatic polyester polyol, 3 parts by weight of a composite crosslinking agent (weight ratio of glycerin to ethylenediamine: 1:1), 0.5 part by weight of a foaming catalyst (PC-12), and 1.8 parts by weight of a gel Catalyst (PC-8), 0.5 part by weight of a polymerization catalyst (TMR-2), 2.0 parts by weight of a silicone oil-based foam stabilizer, 1.6 parts by weight of water, 38 parts by weight of trans-1-chloro-3,3, 3-Trifluoropropene, 133.9 parts by weight of Yantai Wanhua PM2010 (isocyanate index 0.97).

Preparation method 1: pre-mixing components other than isocyanate in the above raw material formula in a stirring pressure tank, and after the pre-mixing is finished, transferring the pre-mixed material to the white working tank of the foaming machine through the pump, and mounting it in black The isocyanate in the working tank was injected into the top I-Mould mold with venting holes (mold size 1100×300×50 mm) or H-Mould mold (mold size 700×) by a high pressure mixing head under a pressure of 140±10 bar. 500×100mm), the mold temperature is 40° C., and then matured for 180 s, and the foam material is obtained after demolding;

Preparation method 2: The refrigerator liner material was cut into 100×40 mm sample pieces, uniformly coated on the I-Mould mold, and the raw materials were mixed in the same manner as in the preparation method 1, and then the I-Mould mold was used (the mold size was The molding was carried out at 700×500×100 mm), the mold temperature was 40° C., the aging was performed for 180 s, and the foam was obtained after demolding.

Example 2

Raw material formula: 40 parts by weight of sorbitol polyether polyol, 21.4 parts by weight of composite polyether polyol, 15 parts by weight of diphenylmethane diamine polyether polyol, 5 parts by weight of glycerol polyether polyol, 10 Parts by weight of aromatic polyester polyol, 3 parts by weight of a composite crosslinking agent (weight ratio of glycerin to ethylenediamine: 1:1), 0.6 parts by weight of a foaming catalyst (PC-12), 1.5 parts by weight of a gel Catalyst (PC-8), 0.5 part by weight of a polymerization catalyst (TMR-2), 2.0 parts by weight of a silicone oil-based foam stabilizer, 1.8 parts by weight of water, and 8 parts by weight of trans-1-chloro-3,3, 3-trifluoropropene, 12 parts by weight of cyclopentane, 5 parts by weight of pentafluoropropane (HFC-245fa), and 137.5 parts by weight of Yantai Wanhua's PM2010 (isocyanate index of 1.10).

Preparation method 1: same as Example 1;

Preparation Method 2: Same as Example 1.

Example 3

Raw material composition: same as in the first embodiment;

Preparation method: components other than isocyanate in the raw material formula are premixed in a stirring pressure tank, and after premixing, the premix is transferred to a white working tank of the foaming machine by a pump, and is installed in a black working tank. The isocyanate was injected into the cavity of the refrigerator through a high pressure mixing head at a pressure of 140 ± 10 bar. The refrigeration equipment selected for testing was a door-to-door air-cooled refrigerator with a foam chamber with a foam thickness of 90 mm, a refrigerator with a foam thickness of 65 mm, a greenhouse with a foam thickness of 65 mm, and a liner material of HIPS/PE alloy. .

Example 4

Raw material composition: same as in the embodiment 2;

Preparation method: same as Example 3.

Comparative example 1

Raw material formula: 20 parts by weight of sorbitol polyether polyol, 21.8 parts by weight of composite polyether polyol, 15 parts by weight of diphenylmethane diamine polyether polyol, 20 parts by weight of glycerol polyether polyol, 15 Parts by weight of aromatic polyester polyol, 3 parts by weight of ethylene glycol crosslinking agent, 0.5 parts by weight of foaming catalyst (PC-12), 1.6 parts by weight of gel catalyst (PC-8), 0.5 parts by weight Polymerization catalyst (TMR-2), 2.0 parts by weight of a silicone-based foam stabilizer, 1.6 parts by weight of water, 38 parts by weight of trans-1-chloro-3,3,3-trifluoropropene, 127.0 parts by weight Yantai Wanhua's PM2010 (isocyanate index is 0.92).

Preparation method 1: same as Example 1;

Preparation Method 2: Same as Example 1.

Comparative example 2

Raw material formula: 40 parts by weight of sorbitol polyether polyol, 21.9 parts by weight of composite polyether polyol, 20 parts by weight of diphenylmethane diamine polyether polyol, and 3 parts by weight of polyether polyol D, 5 Parts by weight of aromatic polyester polyol, 3 parts by weight of ethylenediamine crosslinking agent, 0.5 parts by weight of foaming catalyst (PC-12), 1.6 parts by weight of gel catalyst (PC-8), 0.5 parts by weight Polymerization catalyst (TMR-2), 2.0 parts by weight of a silicone-based foam stabilizer, 2.5 parts by weight of water, 24 parts by weight of trans-1-chloro-3,3,3-trifluoropropene, 142.6 parts by weight Yantai Wanhua's PM2010 (isocyanate index is 1.15).

Preparation method 1: same as Example 1;

Preparation Method 2: Same as Example 1.

Comparative example 3

Raw material composition: the same as the comparative example 2;

Preparation method: same as Example 3.

Evaluation:

1. The thermal conductivity, compressive strength, and molded core density of the foam material obtained in the refrigerator obtained in the same manner as in the foaming material obtained in the same manner as in the production method 1 and Comparative Example 1-2, respectively, in the refrigerator obtained in Example 1-2 and Comparative Example 1-2. The expansion ratio was evaluated, and the bonding strength of the foam obtained in Production Method 2 and the high and low temperature tests of the refrigerator obtained in Example 3-4 and Comparative Example 3 were evaluated for Examples 1-2 and Comparative Examples 1-2.

2. Evaluation indicators and test methods:

Thermal conductivity test: according to ISO 12939-01 / DIN 52612, using an EKO HC-074-200 thermal conductivity meter at an average temperature of 10 ° C (upper plate 2 ° C, lower plate 18 ° C). 24 hours after the preparation of the foam, the foam samples were cut from the center of the molded portion, and these samples were measured immediately after cutting, in units of mW/m·k.

Determination of compressive strength: according to DIN53421-06-84, measured by Shimadzu AGS-J, unit Kpa.

Determination of the density of the molded core: The density of the foamed foam in the same mold except for the skin, measured in accordance with ASTM1622-88, in units of kg/m3.

Determination of expansion ratio: The expansion ratio, in %, was calculated by dividing the difference between the maximum foam thickness after demolding and the original mold thickness by the thickness of the original mold. If the foam is released earlier, the expansion ratio is higher. Similarly, the foam formulation can be demolded earlier, during which the foam expansion rate is small during the same demold time.

Determination of bond strength: According to GB/T26689-2011 (appendix), the adhesion was tested by the Shimadzu AGS-J universal testing machine, bonding strength = adhesion / sample cross-sectional area, unit KPa. The bond strength of the present invention is the average bond strength of 15 samples.

High and low temperature impact test: after foaming, the box is placed for 12h, high and low temperature cycle for 4 cycles (high temperature +70 °C, low temperature -40 °C), 12 hours per cycle, high temperature and low temperature stabilization time should be ≥ 2.5 hours (generally 4 hours), the heating time is within 2 hours, and the cooling time is within 5 hours.

The test results are shown in Tables 1 and 2:

Table 1 Comparison of foam properties of Examples 1-2 and Comparative Examples 1-2

It can be seen from the data in Table 1 that the polyurethane foam prepared by using the proper ratio of the polyol composition and the auxiliary agent in Examples 1 and 2 has low density and low thermal conductivity, and has high compressive strength, and is also between the substrate and the substrate. The bonding strength is higher.

In Comparative Example 1, a high proportion of low-functionality polyether, low-functionality cross-linking agent and a lower isocyanate index were used. Although the adhesive strength was high, the thermal conductivity of the foam was high and the compressive strength was low. In accordance with the production process requirements; Comparative Example 2 uses a high proportion of chemical blowing agent water, a high functionality crosslinking agent and a high isocyanate index, although the compression strength is higher, but the bonding strength of the foam is significantly lower.

Table 2 Comparison of performance of refrigerators of Examples 3 to 4 and Comparative Example 3

As can be seen from the data in Table 2, the foams of the refrigerators prepared in Examples 3 to 4 had a lower molded core density, a lower thermal conductivity, and a higher bond strength than the refrigerator prepared in Comparative Example 3.

In summary, the polyurethane composition of the present invention has small viscosity, mild reaction speed, good fluidity and good adhesion; and the polyurethane foam prepared by using the polyurethane composition of the invention, on the one hand, has a small density (density is less than 28.5). Kg / m ³ ), but with strong adhesion, so that after foaming or high and low temperature impact, the foam and the liner will not be separated; on the other hand, the thermal conductivity is low (less than 17.5mW / m · k) high compressive strength (minimum compressive strength greater than 150Kpa); at the same time, the refrigeration device produced by the polyurethane foam of the invention, such as a refrigerator, has good heat preservation effect and low energy consumption; in addition, the invention adopts low gas phase thermal conductivity, low GWP, Zero ODP foaming agent not only meets energy saving requirements, but also is environmentally friendly and environmentally friendly.

In the description of the present specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means a specific feature described in connection with the embodiment or example. A structure, material or feature is included in at least one embodiment or example of the invention. In the present specification, the schematic representation of the above terms is not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art can combine various embodiments or examples described in the specification and features of different embodiments or examples, and combination.

Although the embodiments of the present invention have been shown and described, it is understood that the above-described embodiments are illustrative and are not to be construed as limiting the scope of the invention. The embodiments are subject to variations, modifications, substitutions and variations.

Claims

A polyurethane composition characterized by comprising:

25 to 60 parts by weight of sorbitol polyether polyol;

15 to 40 parts by weight of the composite polyether polyol;

3 to 30 parts by weight of diphenylmethanediamine polyether polyol;

3 to 15 parts by weight of a glycerin polyether polyol;

3 to 20 parts by weight of an aromatic polyester polyol;

0 to 5 parts by weight of a composite crosslinking agent;

1 to 55 parts by weight of a foaming agent;

1.0 to 5.0 parts by weight of a foam stabilizer;

0.5 to 2.0 parts by weight of water;

1.0 to 3.5 parts by weight of the composite catalyst;

120 to 160 parts by weight of isocyanate,

Wherein the isocyanate has an index of from 0.95 to 1.10.
The polyurethane composition of claim 1 comprising:

25 to 50 parts by weight of the sorbitol polyether polyol;

15 to 30 parts by weight of the composite polyether polyol;

5 to 25 parts by weight of the diphenylmethanediamine polyether polyol;

3 to 10 parts by weight of the glycerin polyether polyol;

5 to 15 parts by weight of the aromatic polyester polyol;

2 to 4 parts by weight of the composite crosslinking agent;

1 to 55 parts by weight of the blowing agent;

1.0 to 5.0 parts by weight of the foam stabilizer;

1.2 to 1.9 parts by weight of the water;

1.0 to 3.5 parts by weight of the composite catalyst;

120 to 160 parts by weight of the isocyanate.
The polyurethane composition according to claim 2, wherein the sorbitol polyol has a hydroxyl value of 380 to 470 mgKOH/g, and the sorbitol polyol has a viscosity of 8,000 to 15000 mPa·s. The sorbitol polyol has a functionality of 6.
The polyurethane compound according to claim 2, wherein the composite polyether polyol is polymerized from sucrose, triethanolamine and propylene oxide, wherein the weight ratio of the sucrose to the triethanolamine is 1-4 :1, said The complex polyether polyol has a functionality of 4-6, the complex polyether polyol has a hydroxyl value of 360-420 mgKOH/g, and the composite polyether polyol has a viscosity of 5000-14000 mPa·s.
The polyurethane composition according to claim 2, wherein the diphenylmethanediamine polyether polyol is polymerized from diphenylmethanediamine, propylene oxide and ethylene oxide, wherein the propylene oxide The weight ratio of the ethylene oxide to the ethylene oxide is 1 to 4:1, the hydroxyl value of the diphenylmethanediamine polyether polyol is 380 to 440 mgKOH/g, and the viscosity of the diphenylmethanediamine polyether polyol is 15000 ~ 25000mpa · s.
The polyurethane composition according to claim 2, wherein the glycerin polyether polyol has a hydroxyl value of from 160 to 300 mgKOH/g, and the glycerin polyether polyol has a viscosity of from 200 to 600 mPa·s.
The polyurethane composition according to claim 2, wherein the aromatic polyester polyol has a hydroxyl value of from 200 to 350 mgKOH/g, and the aromatic polyester polyol has a viscosity of from 1,000 to 2,000 mPa·s. The aromatic polyester polyol has a functionality of 2.7.
The polyurethane composition according to claim 7, wherein the aromatic polyester polyol is a phthalic anhydride polyester.
The polyurethane composition according to claim 2, wherein said blowing agent comprises trans-1-chloro-3,3,3-trifluoropropene, wherein said trans-1-chloro-3 The amount of 3,3-trifluoropropene is from 1 to 55 parts by weight.
The polyurethane composition according to claim 9, wherein the blowing agent further comprises at least one of cyclopentane and pentafluoropropane, wherein the cyclopentane is used in an amount of from 0 to 15 parts by weight. The pentafluoropropane is used in an amount of from 0 to 20 parts by weight.
The polyurethane composition according to claim 2, wherein the composite catalyst is selected from the group consisting of pentamethyldiethylenetriamine, bis-dimethylaminoethyl ether, N-methyldicyclohexylamine, and four At least one of methyl hexamethylene diamine, dimethylcyclohexylamine, 1,2-dimethylimidazole, and dimethylbenzylamine, ammonium trimethylformate, a quaternary ammonium salt, and a quaternary ammonium salt.
The polyurethane composition according to claim 2, wherein the foam stabilizer is a silicone oil.
The polyurethane composition according to claim 2, wherein the composite crosslinking agent is selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, glycerin, trimethylolpropane, pentaerythritol, triethanolamine, ethylenediamine. And at least two of diphenylmethane diamines.
The polyurethane polymer according to claim 2, wherein the isocyanate is a polymethylpolyphenyl polyisocyanate.
A polyurethane foam, which is produced from the polyurethane composition according to any one of claims 1 to 14.
The polyurethane foam according to claim 15, wherein the polyurethane foam has a density of less than 28.5 kg/m 3 .
The polyurethane foam according to claim 15, wherein the polyurethane foam has a small thermal conductivity At 17.5mW/m·k.
The polyurethane foam according to claim 15, wherein the polyurethane foam has a compressive strength of more than 150 kPa.
The polyurethane foam according to claim 15, wherein the polyurethane foam has a bond strength of more than 280 kPa.
A refrigerator comprising the polyurethane foam according to any one of claims 15 to 19.
A method of preparing the polyurethane foam according to any one of claims 15 to 19, comprising:

Providing a premix comprising a sorbitol polyol, a composite polyether polyol, a diphenylmethane diamine polyether polyol, a glycerin polyether polyol, an aromatic polyester polyol, a composite blend a binder, a blowing agent, a foam stabilizer, water, and a composite catalyst;

The premix and isocyanate are injected into a mold for aging treatment to obtain the polyurethane foam.
The method according to claim 21, wherein a refrigerator having a predetermined shape is disposed in the mold.
The method of claim 21 wherein said mold is a cavity of a refrigerator.
The method according to claim 21, wherein the temperature of the mold is 38 to 45 °C.
The method according to claim 21, wherein said preset pressure is 130 to 150 bar.
The method of claim 21 wherein said predetermined time is between 178 and 181 s.