阅读说明：本技术 一种改性石墨阻燃剂及利用该阻燃剂制备全水发泡聚氨酯泡沫及其制备方法 (Modified graphite flame retardant, full-water-blown polyurethane foam prepared from flame retardant and preparation method of full-water-blown polyurethane foam ) 是由 程瑾宁 韩啸 龙燕 包彦彦 于 2019-07-03 设计创作，主要内容包括：本发明涉及聚氨酯泡沫技术领域,具体地说是一种改性石墨阻燃剂及利用该阻燃剂制备全水发泡聚氨酯泡沫及其制备方法,其特征在于该改性石墨阻燃剂由改性可膨胀石墨和分散悬浮剂组成,改性可膨胀石墨为在可膨胀石墨表面吸附一层或多层具有特殊官能团的高分子表面改性剂,该全水发泡聚氨酯泡沫由聚醚多元醇、聚酯多元醇、催化剂、硅油、改性石墨阻燃剂、协效阻燃剂、发泡剂、稳定剂和聚合异氰酸酯组成,通过如下步骤制备：(1)、制备改性可膨胀石墨；(2)、制备可膨胀石墨阻燃剂；(3)、制备全水发泡聚氨酯泡沫,得到全水发泡聚氨酯泡沫,具有阻燃性能好、阻燃效果持久、添加量少、氧指数大幅度提高、热释放速率峰值大幅降低等优点。(The invention relates to the technical field of polyurethane foam, in particular to a modified graphite flame retardant, full-water foaming polyurethane foam prepared by using the flame retardant and a preparation method thereof, and the modified graphite flame retardant is characterized by comprising modified expandable graphite and a dispersing suspending agent, wherein the modified expandable graphite is one or more layers of polymer surface modifiers with special functional groups adsorbed on the surface of the expandable graphite, and the full-water foaming polyurethane foam is prepared from polyether polyol, polyester polyol, a catalyst, silicone oil, the modified graphite flame retardant, a synergistic flame retardant, a foaming agent, a stabilizer and polymeric isocyanate by the following steps: (1) preparing modified expandable graphite; (2) preparing the expandable graphite flame retardant; (3) the full-water foaming polyurethane foam is prepared, and has the advantages of good flame retardant property, lasting flame retardant effect, small addition amount, greatly improved oxygen index, greatly reduced peak value of heat release rate and the like.)

1. The modified graphite flame retardant is characterized by comprising 1-10% of modified expandable graphite and a dispersing suspending agent, wherein the dispersing suspending agent is used for adsorbing one or more layers of polymer surface modifiers with special functional groups on the surface of the expandable graphite, and the polymer surface modifiers are water-soluble compounds, such as polyvinylpyrrolidone, polyethylene glycol, polyacrylate, polyphosphate or melamine, preferably polyvinylpyrrolidone and melamine.

2. The modified graphite flame retardant as claimed in claim 1, wherein the amount of the polymeric surface modifier is 1-20% of the expandable graphite, the expandable graphite has a purity of 90-95%, an average particle size of 100-250 μm and an expansion ratio of 250-300ml/g, and the polymeric surface modifier has more than 2 functional groups, wherein at least one functional group is a five-membered ring or a six-membered ring structure and at least one active functional group is a hydroxyl group, an amine group or a carboxyl group.

3. The modified graphite flame retardant of claim 1, wherein the dispersing and suspending agent is one or more of organic bentonite, polyethylene wax, nano calcium carbonate and polyacrylamide, and preferably is organic bentonite and nano calcium carbonate.

4. The all-water foaming polyurethane foam containing the modified graphite flame retardant is characterized by comprising polyether polyol, polyester polyol, a catalyst, silicone oil, the modified graphite flame retardant, a synergistic flame retardant, a foaming agent, a stabilizer and polymeric isocyanate, wherein the all-water foaming polyurethane foam comprises the following components in parts by mass: 20-40 parts of polyether polyol, 15-45 parts of polyester polyol, 2-6 parts of a catalyst, 1.5-2.5 parts of silicone oil, 20-40 parts of a modified graphite flame retardant, 6-20 parts of a synergistic flame retardant, 3-7 parts of a foaming agent, 5-8 parts of a stabilizer and 0.8-1.5 parts of polymeric isocyanate.

5. The fully water blown polyurethane foam containing modified graphite flame retardant as claimed in claim 4, wherein the polyether polyol is a polyether polyol having an average hydroxyl functionality of 2-8, a hydroxyl value of 200 and 800 mgKOH/g; the polyester polyol is polyester polyol with average hydroxyl functionality of 2-5 and hydroxyl value of 150-400 mgKOH/g.

6. The all-water foaming polyurethane foam containing the modified graphite flame retardant according to claim 4, characterized in that the catalyst is one or two of a foaming catalyst and a gel catalyst or a trimerization catalyst, the weight part of the foaming catalyst is 0.5-1.5 parts, the weight part of the gel catalyst is 0.5-2.5 parts, and the weight part of the trimerization catalyst is 1-2 parts.

7. The all-water blown polyurethane foam containing a modified graphite flame retardant of claim 6, wherein the blowing catalyst is an organic amine; the gel catalyst is mainly ethylene tertiary amine or organic metal; the trimerization catalyst is a potassium or quaternary ammonium salt catalyst; the silicone oil is a liquid organic silicon compound, and the foaming agent is water.

8. The all-water blown polyurethane foam containing the modified graphite flame retardant according to claim 4, wherein the synergistic flame retardant is a flame retardant containing phosphorus, nitrogen, chlorine or bromine, which can form a synergistic flame retardant with the flame retardancy of the modified graphite, and is one or more of tris (2-chloroethyl) phosphate, tris (2-chloropropyl) phosphate, also known as tris (chloroisopropyl) phosphate, diethyl ethylphosphate, microencapsulated red phosphorus powder, ammonium polyphosphate and melamine cyanurate.

9. The all-water foaming polyurethane foam containing the modified graphite flame retardant as claimed in claim 4, wherein the stabilizer is a basic organic substance capable of reacting with hydrogen ions, and is one or more of triethanolamine, diethanolamine, dimethylethanolamine and dimorpholinodiethylether; the polymeric isocyanate is one or a mixture of PM-200, PM-400, M20s, 5050, PAPI27 and PAPI 135.

10. A preparation method of full-water foaming polyurethane foam containing modified graphite flame retardant is characterized by comprising the following steps:

(1) preparing modified expandable graphite: a. shaping process: placing expandable graphite into a mechanical impact type pulverizer for shaping, then classifying by a vibrating screen, returning to the production again when the particle size is smaller than 80 meshes, and entering a next modification working section when the particle size is 80-150 meshes for additional treatment when the particle size is larger than 150 meshes; b. the modification process comprises the following steps: b, placing the expandable graphite of 80-150 meshes obtained in the step a into a stirrer, stirring at a low speed of 50-85r/min, adding the polymer surface modifier, stirring for 10-15 minutes, increasing the rotating speed to 150-200r/min, stirring for 20-30 minutes, and sieving by using an 80-mesh sieve to obtain the modified expandable graphite;

(2) preparing the expandable graphite flame retardant: adding the modified expandable graphite in the step (1) into a dispersing and suspending agent, and uniformly mixing in a stainless steel stirrer at a low rotating speed of below 500r/min to obtain a modified graphite flame retardant;

(3) preparing full-water foaming polyurethane foam: adding polyester polyol and polyether polyol into a stirring tank, starting stirring at the rotating speed of 40-60r/min, sequentially adding silicone oil, a synergistic flame retardant, a stabilizer, a catalyst and a modified graphite flame retardant, adjusting the rotating speed to 60-80r/min, mixing for 15-20 minutes, injecting the obtained polyurethane composite material into the stirring tank of a foaming machine after sampling and detecting are qualified, adding a foaming agent, adjusting the stirring rotating speed to 50-70r/min, and uniformly stirring; simultaneously, injecting the polymeric isocyanate into the other stirring tank of the foaming machine; and uniformly mixing the two materials by a foaming machine, injecting the mixture into a mould, foaming, curing and curing to obtain the full-water foaming polyurethane foam.

Technical Field

The invention relates to the technical field of polyurethane foam, in particular to a modified graphite flame retardant which has the advantages of reasonable formula, good flame retardant property, lasting flame retardant effect, small addition amount, greatly improved oxygen index and greatly reduced peak value of heat release rate, and full-water foaming polyurethane foam prepared by using the flame retardant and a preparation method thereof.

Background

As is well known, polyurethane foam has the outstanding characteristics of low density, good insulation, high compressive strength, excellent mechanical properties, simple molding process and the like, and is widely applied to various fields. Conventional blowing agents for producing polyurethane foams include hydrochlorofluorocarbon blowing agents, hydrocarbon blowing agents typified by cyclopentane, and water and hydrofluorocarbons. The hydrocarbon foaming agent is flammable and explosive, and is not suitable for field construction. The chlorofluorocarbon foaming agents commonly used at present still have a certain destructive effect on the ozone layer. The ODP value of the foaming agent water is zero, and the foaming agent water is safe and environment-friendly. CO produced by the reaction of water with the polyisocyanate is used₂It is particularly important to achieve the production of foamed water blown polyurethane foams. However, the conventional all-water foaming polyurethane foam composition material has the defects of high viscosity, poor fluidity, poor flame retardant property, poor dimensional stability, high heat conductivity coefficient and the like. Therefore, the flame retardance of the flame-retardant rubber is improved, so that the flame-retardant rubber becomes a material with excellent comprehensive performance and has important significance.

In recent years, flame retardation modification studies of polyurethane foams have been mainly conducted by using additive-type or reactive flame retardants. The Expandable Graphite (EG) is an additive flame retardant commonly used for polyurethane, the EG does not contain halogen and is non-toxic, smoke released in combustion is little, the flame retardant efficiency is high, when a polymer filled with the EG meets a heat source, the volume of the polymer expands rapidly, a physical coating carbon layer is formed on the surface of the polymer, heat is isolated, and a foam matrix is protected, so that the polymer matrix has good flame retardant performance. However, the flame retardant efficiency is affected by the particle size, density and addition amount, especially the popcorn effect, namely, the loose worm-shaped carbon layer is easy to fall off under the disturbance of flame impact, and the flame retardant and smoke suppression effects of EG are seriously affected. In addition, the expanded graphite has the problems of poor compatibility with polymers, uneven dispersion, easy agglomeration, easy precipitation, difficult stirring and the like in the composite material, so that the graphite is unevenly distributed in the foam. The phosphorus flame retardant has the advantages of high phosphorus content, good thermal stability, good dispersibility, low toxicity and the like, can capture combustible free radicals generated by combustion to interrupt combustion chain reaction, plays an excellent gas-phase flame retardant role, can promote dehydration and carbonization during initial decomposition of a polymer, improves the char yield of the polymer, and has good flame retardance. And the flame retardant polyurethane compounded with EG can effectively relieve the popcorn effect. Meanwhile, EG adopts surface modification treatment to solve the problem of dispersion in the polymer.

Chinese patent CN105542101A discloses a compound intumescent flame retardant for polyurethane foam, the halogen-free compound flame retardant is composed of a novel phosphorus-nitrogen intumescent polyol and expandable graphite, and the obtained flame-retardant rigid polyurethane foam has better flame retardant property. Although the added novel phosphorus-nitrogen intumescent polyol has the advantages of good flame retardant property durability, small influence on the physical and mechanical properties of products and the like, the synthesis process for introducing the flame retardant element into the polyol is complex, the cost is high, and the industrialization difficulty is high. Meanwhile, the expandable graphite has few reactive groups on the surface of the graphite layer, has weak interface acting force with a matrix material, is not directly added after being treated on the surface, has serious agglomeration phenomenon, can not effectively ensure the dispersion uniformity of the expandable graphite in the foam material, and can seriously affect the mechanical property of the polyurethane foam material. Patent CN105713167A discloses a high flame-retardant rigid polyurethane foam plastic and a preparation method thereof, and the rigid polyurethane foam plastic prepared by the synergistic effect of modified expandable graphite and a halogen-free flame retardant has good flame-retardant property and a simple preparation method process. However, no mention is made of the purity, particle size, expansion ratio and other indexes of the expandable graphite, and the flame retardant effect of the expandable graphite in the polyurethane foam is closely related to the particle size, expansion ratio and the like. The larger the particle size is, the better the flame retardant effect is, but the mechanical property of the foam is reduced and the heat conductivity coefficient is increased; when the particle size is smaller, although the influence on the mechanical property and the heat conductivity coefficient of the foam is smaller, the flame retardant effect is also obviously reduced. Patent CN108822277A discloses a polyurethane foam using organosilicon modified expanded graphite as flame retardant, which mainly comprises the following components: polyester polyol, 1, 4-cyclohexane diisocyanate, hydroxyl-terminated fluorosilicone resin, stannous octoate, triethylene diamine, a surfactant, an antioxidant and a drier. The obtained product has good flame retardant effect, no residual raw materials in the foam, and no harm to human body. But the modification treatment of the expandable graphite is mainly surface modification by organic silicon, and chemical grafting modification of functional groups of the expandable graphite is not involved.

Disclosure of Invention

The invention aims to solve the defects of the prior art and provide the all-water foaming polyurethane foam containing the modified graphite flame retardant, which has the advantages of reasonable formula, good flame retardant property, lasting flame retardant effect, small addition amount, greatly improved oxygen index and greatly reduced peak value of heat release rate.

The technical scheme adopted by the invention for solving the technical problems is as follows:

the modified graphite flame retardant is characterized by comprising 1-10% of modified expandable graphite and a dispersing suspending agent, wherein the dispersing suspending agent is used for adsorbing one or more layers of polymer surface modifiers with special functional groups on the surface of the expandable graphite, and the polymer surface modifiers are water-soluble compounds, such as polyvinylpyrrolidone, polyethylene glycol, polyacrylate, polyphosphate and melamine, preferably the polyvinylpyrrolidone and the melamine.

The dosage of the macromolecular surface modifier is 1-20% of the expandable graphite, the purity of the expandable graphite is 90-95%, the average sheet diameter is 100-.

The dispersion suspending agent is one or more of organic bentonite, polyethylene wax, nano calcium carbonate and polyacrylamide, and preferably organic bentonite and nano calcium carbonate.

The all-water foaming polyurethane foam containing the modified graphite flame retardant is characterized by comprising polyether polyol, polyester polyol, a catalyst, silicone oil, the modified graphite flame retardant, a synergistic flame retardant, a foaming agent, a stabilizer and polymeric isocyanate, wherein the all-water foaming polyurethane foam comprises the following components in parts by mass: 20-40 parts of polyether polyol, 15-45 parts of polyester polyol, 2-6 parts of a catalyst, 1.5-2.5 parts of silicone oil, 20-40 parts of a modified graphite flame retardant, 6-20 parts of a synergistic flame retardant, 3-7 parts of a foaming agent, 5-8 parts of a stabilizer and 0.8-1.5 parts of polymeric isocyanate.

The polyether polyol is polyether polyol with the average hydroxyl functionality of 2-8 and the hydroxyl value of 200-800 mgKOH/g; the polyester polyol is polyester polyol with average hydroxyl functionality of 2-5 and hydroxyl value of 150-400 mgKOH/g.

The catalyst is one or two of a foaming catalyst and a gel catalyst or a trimerization catalyst, the foaming catalyst is 0.5-1.5 parts by weight, the gel catalyst is 0.5-2.5 parts by weight, and the trimerization catalyst is 1-2 parts by weight.

The foaming catalyst is organic amine; the gel catalyst is mainly ethylene tertiary amine or organic metal; the trimerization catalyst is a potassium or quaternary ammonium salt catalyst; the silicone oil is a liquid organic silicon compound, and the foaming agent is water.

The synergistic flame retardant is a flame retardant containing phosphorus, nitrogen, chlorine or bromine and capable of forming synergistic flame retardance with the flame retardance of the modified graphite, and is one or more of tris (2-chloroethyl) phosphate, tris (2-chloropropyl) phosphate, namely tris (chloroisopropyl) phosphate, diethyl ethylphosphate, microencapsulated red phosphorus powder, ammonium polyphosphate and melamine cyanurate.

The stabilizer is an alkaline organic matter capable of reacting with hydrogen ions, and is one or more of triethanolamine, diethanolamine, dimethylethanolamine and dimorpholinyl diethyl ether; the polymeric isocyanate is one or a mixture of PM-200, PM-400, M20s, 5050, PAPI27 and PAPI 135.

A preparation method of full-water foaming polyurethane foam containing modified graphite flame retardant is characterized by comprising the following steps:

(1) preparing modified expandable graphite: a. shaping process: placing expandable graphite into a mechanical impact type pulverizer for shaping, then classifying by a vibrating screen, returning to the production again when the particle size is smaller than 80 meshes, and entering a next modification working section when the particle size is 80-150 meshes for additional treatment when the particle size is larger than 150 meshes; b. the modification process comprises the following steps: b, placing the expandable graphite of 80-150 meshes obtained in the step a into a stirrer, stirring at a low speed of 50-85r/min, adding the polymer surface modifier, stirring for 10-15 minutes, increasing the rotating speed to 150-200r/min, stirring for 20-30 minutes, and sieving by using an 80-mesh sieve to obtain the modified expandable graphite;

(2) preparing the expandable graphite flame retardant: adding the modified expandable graphite in the step (1) into a dispersing and suspending agent, and uniformly mixing in a stainless steel stirrer at a low rotating speed of below 500r/min to obtain a modified graphite flame retardant;

(3) preparing full-water foaming polyurethane foam: adding polyester polyol and polyether polyol into a stirring tank, starting stirring at the rotating speed of 40-60r/min, sequentially adding silicone oil, a synergistic flame retardant, a stabilizer, a catalyst and a modified graphite flame retardant, adjusting the rotating speed to 60-80r/min, mixing for 15-20 minutes, injecting the obtained polyurethane composite material into the stirring tank of a foaming machine after sampling and detecting are qualified, adding a foaming agent, adjusting the stirring rotating speed to 50-70r/min, and uniformly stirring; simultaneously, injecting the polymeric isocyanate into the other stirring tank of the foaming machine; and uniformly mixing the two materials by a foaming machine, injecting the mixture into a mould, foaming, curing and curing to obtain the full-water foaming polyurethane foam.

The catalyst is one or two of a foaming catalyst and a gel catalyst or a trimerization catalyst, namely the catalyst is in three forms of the foaming catalyst and the gel catalyst, the foaming catalyst and the trimerization catalyst or the foaming catalyst, the gel catalyst and the trimerization catalyst.

The foaming catalyst is 0.5-1.5 parts by weight, the gel catalyst is 0.5-2.5 parts by weight, and the trimerization catalyst is 1-2 parts by weight.

By adopting the formula and the preparation process, the all-water foaming polyurethane foam obtained by adding the modified graphite flame retardant and the synergistic flame retardant has the advantages of good flame retardant property, lasting flame retardant effect, small addition amount, greatly improved oxygen index, greatly reduced peak value of heat release rate and the like.

Detailed Description

The invention is further illustrated below:

a modified graphite flame retardant is characterized in that the modified graphite flame retardant consists of modified expandable graphite and a dispersing suspending agent, the dosage of the dispersing suspending agent is 1% -10% of that of the modified expandable graphite, the modified expandable graphite is one or more layers of polymer surface modifiers with special functional groups adsorbed on the surface of the expandable graphite, the polymer surface modifiers are water-soluble compounds and are polyvinylpyrrolidone, polyethylene glycol, polyacrylate, polyphosphate and melamine, preferably polyvinylpyrrolidone and melamine, the dosage of the polymer surface modifiers is 1% -20% of that of the expandable graphite, the purity of the expandable graphite is 90% -95%, the average sheet diameter is 100-, wherein at least one functional group is a five-membered ring or six-membered ring structure, at least one active functional group is hydroxyl, amido or carboxyl, the dispersing and suspending agent is one or more of organic bentonite, polyethylene wax, nano calcium carbonate and polyacrylamide, and the organic bentonite and the nano calcium carbonate are preferred.

The all-water foaming polyurethane foam containing the modified graphite flame retardant is characterized by comprising polyether polyol, polyester polyol, a catalyst, silicone oil, the modified graphite flame retardant, a synergistic flame retardant, a foaming agent, a stabilizer and polymeric isocyanate, wherein the all-water foaming polyurethane foam comprises the following components in parts by mass: 20-40 parts of polyether polyol, 15-45 parts of polyester polyol, 2-6 parts of catalyst, 1.5-2.5 parts of silicone oil, 20-40 parts of modified graphite flame retardant, 6-20 parts of synergistic flame retardant, 3-7 parts of foaming agent, 5-8 parts of stabilizer and 0.8-1.5 parts of polymeric isocyanate, wherein the polyether polyol refers to polyether polyol with the average hydroxyl functionality of 2-8 and the hydroxyl value of 200-; the polyester polyol is polyester polyol with the average hydroxyl functionality of 2-5 and the hydroxyl value of 150-400mgKOH/g, the catalyst is one or two of a foaming catalyst and a gel catalyst or a trimerization catalyst, the weight part of the foaming catalyst is 0.5-1.5 parts, the weight part of the gel catalyst is 0.5-2.5 parts, the weight part of the trimerization catalyst is 1-2 parts, and the foaming catalyst is organic amine; the gel catalyst is mainly ethylene tertiary amine or organic metal; the trimerization catalyst is a potassium or quaternary ammonium salt catalyst; the silicone oil is a liquid organic silicon compound, the foaming agent is water, the synergistic flame retardant is a flame retardant containing phosphorus, nitrogen, chlorine or bromine and capable of forming synergistic flame retardance with the flame retardance of modified graphite, is one or more of tris (2-chloroethyl) phosphate, tris (2-chloropropyl) phosphate, namely tris (chloroisopropyl) phosphate, diethyl ethylphosphate, microcapsule red phosphorus powder, ammonium polyphosphate and melamine cyanurate salt, and the stabilizer is an alkaline organic matter capable of reacting with hydrogen ions and is one or more of triethanolamine, diethanolamine, dimethylethanolamine and dimorpholinyl diethylether; the polymeric isocyanate is one or a mixture of PM-200, PM-400, M20s, 5050, PAPI27 and PAPI135, and the preparation method comprises the following steps: (1) preparing modified expandable graphite: a. shaping process: placing expandable graphite into a mechanical impact type pulverizer for shaping, then classifying by a vibrating screen, returning to the production again when the particle size is smaller than 80 meshes, and entering a next modification working section when the particle size is 80-150 meshes for additional treatment when the particle size is larger than 150 meshes; b. the modification process comprises the following steps: b, placing the expandable graphite of 80-150 meshes obtained in the step a into a stirrer, stirring at a low speed of 50-85r/min, adding the polymer surface modifier, stirring for 10-15 minutes, increasing the rotating speed to 150-200r/min, stirring for 20-30 minutes, and sieving by using an 80-mesh sieve to obtain the modified expandable graphite; (2) preparing the expandable graphite flame retardant: adding the modified expandable graphite in the step (1) into a dispersing and suspending agent, and uniformly mixing in a stainless steel stirrer at a low rotating speed of below 500r/min to obtain a modified graphite flame retardant; (3) preparing full-water foaming polyurethane foam: adding polyester polyol and polyether polyol into a stirring tank, starting stirring at the rotating speed of 40-60r/min, sequentially adding silicone oil, a synergistic flame retardant, a stabilizer, a catalyst and a modified graphite flame retardant, adjusting the rotating speed to 60-80r/min, mixing for 15-20 minutes, injecting the obtained polyurethane composite material into the stirring tank of a foaming machine after sampling and detecting are qualified, adding a foaming agent, adjusting the stirring rotating speed to 50-70r/min, and uniformly stirring; simultaneously, injecting the polymeric isocyanate into the other stirring tank of the foaming machine; the two are evenly mixed by a foaming machine and then injected into a mould to be foamed, cured and cured to obtain the full-water foaming polyurethane foam, wherein the catalyst is one or two of a foaming catalyst and a gel catalyst or a trimerization catalyst, namely the catalyst is in three forms of a foaming catalyst and a gel catalyst, a foaming catalyst and a trimerization catalyst or a foaming catalyst, a gel catalyst and a trimerization catalyst.

Compared with the prior art, the invention has the following advantages and beneficial effects:

1. the invention adopts the macromolecular modifier to carry out surface modification on the expandable graphite, and the hydroxyl and the six-membered ring are loaded on the surface of the expandable graphite, so that the agglomeration phenomenon of the modified expandable graphite is obviously weakened, the compatibility with polyurethane is greatly improved, and the dispersibility is improved.

2. The expansion rate of the modified expandable graphite obtained by the invention is obviously reduced, the expanded carbon layer becomes more compact, the oxygen index of the prepared heat insulation material is more than or equal to 30%, the oxygen index after dry heat aging is more than or equal to 30%, and the fire safety of the heat insulation material is effectively improved.

3. The thermal stability of the all-water foaming polyurethane foam obtained by the invention is enhanced, and the flame retardance and the mechanical property of the composite material are improved.

4. The full water-blown polyurethane combined polyether obtained by the invention adopts hydrolysis-resistant polyol and hydrolysis-resistant catalyst, so that the storage life of the combined polyether is prolonged.

The present invention will be further described with reference to the following examples.