阅读说明：本技术 一种无卤阻燃泡沫材料及其制备方法和应用 (Halogen-free flame-retardant foam material and preparation method and application thereof ) 是由 顾晓华 龚子龙 吕士伟 刘吉峰 于 2021-07-08 设计创作，主要内容包括：本发明属于阻燃聚氨酯材料技术领域,具体涉及一种无卤阻燃泡沫材料及其制备方法和应用。本发明提供的无卤阻燃泡沫材料的制备方法,包括以下步骤：将废旧聚氨酯、醇解剂、助醇解剂、磷系阻燃剂和氧化石墨烯混合,进行降解反应,得到降解多元醇,所述磷系阻燃剂为含有双羟基DOPO反应型阻燃剂和双羧基DOPO反应型阻燃剂中的一种或多种；将A组分和异氰酸酯类化合物混合进行发泡,得到所述无卤阻燃泡沫材料,所述A组分包括所述降解多元醇、扩链剂、发泡剂、催化剂和稳定剂。本发明提供的制备方法得到的无卤阻燃泡沫材料的压缩强度高,且具有优异的表观密度和极限氧指数。(The invention belongs to the technical field of flame-retardant polyurethane materials, and particularly relates to a halogen-free flame-retardant foam material and a preparation method and application thereof. The preparation method of the halogen-free flame-retardant foam material provided by the invention comprises the following steps: mixing waste polyurethane, an alcoholysis agent, an alcoholysis assistant agent, a phosphorus flame retardant and graphene oxide, and performing a degradation reaction to obtain degraded polyol, wherein the phosphorus flame retardant is one or more of a dihydroxyl DOPO reaction type flame retardant and a dicarboxyl DOPO reaction type flame retardant; and mixing the component A and an isocyanate compound for foaming to obtain the halogen-free flame-retardant foam material, wherein the component A comprises the degradation polyol, a chain extender, a foaming agent, a catalyst and a stabilizer. The halogen-free flame-retardant foam material prepared by the preparation method provided by the invention has high compression strength, and excellent apparent density and limiting oxygen index.)

1. The preparation method of the halogen-free flame-retardant foam material is characterized by comprising the following steps:

mixing waste polyurethane, an alcoholysis agent, an alcoholysis assistant agent, a phosphorus flame retardant and graphene oxide, and performing a degradation reaction to obtain degraded polyol, wherein the phosphorus flame retardant is one or more of a dihydroxyl DOPO reaction type flame retardant and a dicarboxyl DOPO reaction type flame retardant;

and mixing the component A and an isocyanate compound for foaming to obtain the halogen-free flame-retardant foam material, wherein the component A comprises the degradation polyol, a chain extender, a foaming agent, a catalyst and a stabilizer.

2. The preparation method according to claim 1, wherein the phosphorus-based flame retardant comprises one or more compounds having a structure represented by formulas I to V;

3. the method of claim 1, wherein the alcoholysis agent comprises a first alcoholysis agent and a second alcoholysis agent; the first alcoholysis agent comprises one or more of dihydric alcohol, sorbitol, polyether polyol and polyester polyol, and the second alcoholysis agent comprises an alcohol amine compound;

the alcoholysis assistant agent comprises one or more of amine compounds, inorganic strong base and organic titanium compounds.

4. The preparation method of claim 3, wherein the mass ratio of the total mass of the first alcoholysis agent, the second alcoholysis agent, the alcoholysis assistant agent, the phosphorus flame retardant and the graphene oxide to the waste polyurethane is (1-1.2): 1.

5. The method of claim 3, wherein the first alcoholysis agent, the second alcoholysis agent, the alcoholysis assistant agent, the phosphorus-based flame retardant and the graphene oxide are present in a mass ratio of (40-60): (35-50): 1-5): 0.1-5.

6. The preparation method according to claim 1, wherein the temperature of the degradation reaction is 140-250 ℃ and the time is 5-10 h.

7. The preparation method according to claim 1, wherein the mass ratio of the degraded polyol to the foaming agent in the component A is 1 (0.5-3.5).

8. The preparation method according to claim 1 or 7, wherein the mass ratio of the chain extender, the foaming agent, the catalyst and the stabilizer in the component A is (0.1-10): (5-35): (0.1-10).

9. The halogen-free flame-retardant foam material prepared by the preparation method of any one of claims 1 to 8, wherein the apparent density of the halogen-free flame-retardant foam material is 36.17-38.28 kg/m³。

10. Use of the halogen-free flame-retardant foam material according to claim 9 in automotive, transportation, civil construction, light industry, textile, electromechanical or petrochemical engineering.

Technical Field

The invention belongs to the technical field of flame-retardant polyurethane materials, and particularly relates to a halogen-free flame-retardant foam material and a preparation method and application thereof.

Background

The halogen-free flame-retardant rigid polyurethane foam plastic is a highly cross-linked thermosetting material mainly synthesized by isocyanate, polyol and phosphorus flame retardant. Because of its excellent physical and chemical properties such as high bonding strength after curing, shock resistance and compression resistance and good flame retardant property, it is widely used in many fields such as automobile manufacturing, transportation, civil construction, light industry, textile, electromechanical and petrochemical industries.

At present, the research on halogen-free flame retardant foam materials at home and abroad is mainly carried out in the polymerization reaction of polyurethane preparation, for example, "the research on halogen-free flame retardant of thermoplastic polyurethane elastomer progresses" published in 2019 by Wangkangqi, Cujing and the like; "research progress on halogen-free flame retardant rigid polyurethane foam" published in 2020 by WangJingyu, Hedgehog.

In 2018, the research on recycling waste polyurethane to prepare halogen-free flame-retardant foam is reported in Korean Rui, Kuwawa and the like. However, the flame retardant in the article is a physical addition mode adopted in the foaming process, and is not a chemical reaction method participating in the degradation reaction in the chemical degradation process of reactive polyurethane, so that the compatibility of the components added with the flame retardant in a physical blending mode and other components of the halogen-free flame-retardant foam is poor, the final foaming effect is influenced, and the prepared flame-retardant foam has poor flame-retardant effect and low strength.

Disclosure of Invention

In view of the above, the invention provides a halogen-free flame-retardant foam material, and a preparation method and an application thereof.

The invention provides a preparation method of a halogen-free flame-retardant foam material, which comprises the following steps:

mixing waste polyurethane, an alcoholysis agent, an alcoholysis assistant agent, a phosphorus flame retardant and graphene oxide, and performing a degradation reaction to obtain degraded polyol, wherein the phosphorus flame retardant is one or more of a dihydroxyl DOPO reaction type flame retardant and a dicarboxyl DOPO reaction type flame retardant;

and mixing the component A and an isocyanate compound for foaming to obtain the halogen-free flame-retardant foam material, wherein the component A comprises the degradation polyol, a chain extender, a foaming agent, a catalyst and a stabilizer.

Preferably, the phosphorus flame retardant comprises one or more compounds with structures shown in formulas I-V;

preferably, the alcoholysis agent comprises a first alcoholysis agent and a second alcoholysis agent; the first alcoholysis agent comprises one or more of dihydric alcohol, sorbitol, polyether polyol and polyester polyol, and the second alcoholysis agent comprises an alcohol amine compound;

the alcoholysis assistant agent comprises one or more of amine compounds, inorganic strong base and organic titanium compounds.

Preferably, the mass ratio of the total mass of the first alcoholysis agent, the second alcoholysis agent, the alcoholysis assistant agent, the phosphorus flame retardant and the graphene oxide to the waste polyurethane is (1-1.2): 1.

Preferably, the mass ratio of the first alcoholysis agent to the second alcoholysis agent to the alcoholysis assistant agent to the phosphorus flame retardant to the graphene oxide is (40-60): 35-50): 1-5): 0.1-5.

Preferably, the temperature of the degradation reaction is 140-250 ℃ and the time is 5-10 h.

Preferably, in the component A, the mass ratio of the degradation polyol to the foaming agent is 1 (0.5-3.5).

Preferably, in the component A, the mass ratio of the chain extender, the foaming agent, the catalyst and the stabilizer is (0.1-10): (5-35): (0.1-10).

The invention providesAccording to the halogen-free flame-retardant foam material prepared by the preparation method in the technical scheme, the apparent density of the halogen-free flame-retardant foam material is 36.17-38.28 kg/m³。

The invention provides the application of the halogen-free flame-retardant foam material in the technical scheme in automobile manufacturing, transportation, civil construction, light industry, textile, electromechanics or petrochemical industry.

The invention provides a preparation method of a halogen-free flame-retardant foam material, which comprises the following steps: mixing waste polyurethane, an alcoholysis agent, an alcoholysis assistant agent, a phosphorus flame retardant and graphene oxide, and performing a degradation reaction to obtain degraded polyol, wherein the phosphorus flame retardant is one or more of a dihydroxyl DOPO reaction type flame retardant and a dicarboxyl DOPO reaction type flame retardant; and mixing the component A and an isocyanate compound for foaming to obtain the halogen-free flame-retardant foam material, wherein the component A comprises the degradation polyol, a chain extender, a foaming agent, a catalyst and a stabilizer. According to the preparation method provided by the invention, the DOPO reaction type flame retardant with a dicarboxyl or dihydroxyl structure is used as a phosphorus flame retardant, can participate in a crosslinking reaction in a waste polyurethane degradation process, and is subjected to a polymerization reaction with a waste polyurethane alcoholysis product to be combined with a main chain or a branched chain of a degradation polyol, so that the defects that the flame retardant in a foam system is easy to migrate, cannot keep a flame retardant effect for a long time, and damages the physical and mechanical properties of a foam material can be well overcome; meanwhile, the graphene oxide is added into a system for degrading polyurethane, the graphene oxide is rich in hydroxyl and can chemically react with a terminal group in the polyurethane degradation system to form a chemical connection point of the terminal group of the degraded polyol, so that the graphene oxide is connected to the terminal group of the degraded polyol through a chemical bond and becomes an intersection point of a thermosetting cross-linked network structure during polymerization, and compared with the case that the graphene oxide is doped into the polyurethane system in a physical mode, the graphene oxide chemically combined in the cross-linked network structure of the polyurethane has firmer bonding force, shows a more stable and firmer cross-linked network structure of the polyurethane, and is not easily damaged by external force. And also; the preparation method provided by the invention comprises the following steps of adding graphene oxide: in one aspect, graphite oxideThe alkene can be used as a nucleating agent to promote the foaming of polyurethane, so that the diameter of cells becomes small and the number becomes uniform for many times; on the other hand, the carbon atom of graphene oxide is represented by sp²The material with a two-dimensional cellular structure formed by a hybridization mode has a special single-atom layered structure, so that the material has excellent thermal and mechanical properties, and the addition of the graphene oxide can also improve the skeleton strength of polyurethane foam; finally; the two-dimensional lamellar structure of the graphene oxide can be stacked layer by layer in the foam to form a compact physical isolation layer, so that the flame retardant property is improved. The graphene can be crosslinked and compounded with a thermosetting crosslinked network structure of foam to further form a compact protective film, so that the air is blocked, and the flame retardant effect is achieved. The graphene composite material burns at high temperature to generate carbon dioxide and water, and generates a more compact and continuous carbon layer, so that the barrier effect is stronger, and the synergistic barrier effect is achieved, thereby being synergistic with the flame retardant of the DOPO reaction type flame retardant. Therefore, the halogen-free flame-retardant foam material prepared by the invention has good flame-retardant effect and high compression strength; the results of the examples show that the halogen-free flame-retardant foam material prepared by the preparation method provided by the invention has high compressive strength, and excellent apparent density and Limiting Oxygen Index (LOI).

The preparation method provided by the invention takes the waste polyurethane as the raw material, reduces the cost of the foaming material, is green and environment-friendly, and obtains remarkable economic benefit.

Detailed Description

The invention provides a preparation method of a halogen-free flame-retardant foam material, which comprises the following steps:

mixing waste polyurethane, an alcoholysis agent, an alcoholysis assistant agent, a phosphorus flame retardant and graphene oxide, and performing a degradation reaction to obtain degraded polyol, wherein the phosphorus flame retardant is one or more of a dihydroxyl DOPO reaction type flame retardant and a dicarboxyl DOPO reaction type flame retardant;

and mixing the component A and an isocyanate compound for foaming to obtain the halogen-free flame-retardant foam material, wherein the component A comprises the degradation polyol, a chain extender, a foaming agent, a catalyst and a stabilizer.

In the present invention, the starting materials are all commercially available products well known to those skilled in the art, unless otherwise specified.

According to the invention, waste polyurethane, an alcoholysis agent, an alcoholysis assistant agent, a phosphorus flame retardant and graphene oxide are mixed (hereinafter referred to as first mixing) to carry out a degradation reaction, so as to obtain the degraded polyol.

In the present invention, the waste polyurethane is preferably derived from scrap in the production of polyurethane and/or use of aged polyurethane. The waste polyurethane raw material is preferably subjected to pretreatment, and in the invention, the pretreatment is preferably as follows: washing, drying and crushing are carried out in sequence; in the invention, the washing is preferably water washing, and the invention has no special requirements on the specific implementation processes of washing, drying and crushing; in the invention, the particle size of the waste polyurethane is preferably 5-20 mm.

In the present invention, the alcoholysis agent comprises a first alcoholysis agent and a second alcoholysis agent; the first alcoholysis agent preferably comprises one or more of a diol, sorbitol, polyether polyol, and polyester polyol; the dihydric alcohol preferably comprises one or more of ethylene glycol, propylene glycol, pentanediol and butynediol, and the polyether polyol preferably comprises one or more of polyether polyol GR-635C, polyether polyol GR-4110A, polyether polyol GR-4110G, polyether polyol GR-450A, polyether polyol GR-649, polyether polyol GR-8340A, polyether polyol GR-835G, polyether polyol GRA-6360 and polyether polyol PEDA-1500; the polyester polyol preferably comprises the polyester polyol PEBA-2000 and/or the polyester polyol PEDA-2000. In the present invention, the first alcoholysis agent more preferably comprises sorbitol or a glycol, and most preferably comprises sorbitol, pentanediol, butynediol, propylene glycol, or ethylene glycol.

In the invention, the first alcoholysis agent is used as a reactant to participate in the degradation reaction of the waste polyurethane, so that the waste polyurethane is degraded into polyol.

In the present invention, the second alcoholysis agent preferably comprises an alcoholamine compound, more preferably comprises ethanolamine and/or propanolamine, and in a specific embodiment of the present invention, the second alcoholysis agent is preferably ethanolamine or propanolamine.

In the invention, the second alcoholysis agent is used as a reactant to participate in the degradation reaction of polyurethane, and is matched with the first alcoholysis agent to accelerate the degradation rate of the waste polyurethane.

In the present invention, the alcoholysis assistant preferably comprises one or more of an amine compound, an inorganic strong base and an organic titanium compound, wherein the amine compound preferably comprises N, N-dimethylethanolamine, cyclohexylamine or a tertiary amine, the inorganic strong base is preferably an alkali metal hydroxide, more preferably sodium hydroxide and/or potassium hydroxide, and the organic titanium compound is preferably ethylene glycol titanium and/or tetrabutyl titanate; in the present invention, the alcoholysis aid more preferably comprises diethanolamine and/or tetrabutyltitanate.

In the invention, the phosphorus flame retardant is one or more of dihydroxyl DOPO reaction type flame retardants and dicarboxyl DOPO reaction type flame retardants, and more preferably one or more of compounds with structures shown in formulas I-V;

in a specific embodiment of the present invention, the phosphorus-based flame retardant is a compound having a structure represented by formula I, formula II, formula III, formula VI, or formula V.

In the invention, the particle size of the graphene oxide is preferably 0.5-40 μm, more preferably 5-30 μm, and most preferably 10-20 μm.

In the invention, the mass ratio of the total mass of the first alcoholysis agent, the second alcoholysis agent, the alcoholysis assistant agent, the phosphorus flame retardant and the graphene oxide to the waste polyurethane is preferably (1-1.2): 1.

In the invention, the mass ratio of the first alcoholysis agent, the second alcoholysis agent, the alcoholysis assistant agent, the phosphorus flame retardant and the graphene oxide is preferably (40-60): 35-50): 1-5): 0.1-5), more preferably (45-55): 40-45): 1.5-4): 0.5-3.5.

In the invention, the first mixing is preferably carried out under the condition of stirring, and the invention has no special requirement on the specific implementation process of the stirring so as to realize uniform mixing of the degradation raw materials.

In the invention, the temperature of the degradation reaction is preferably 140-250 ℃, and more preferably 150-230 ℃; the time of the degradation reaction is preferably 5-10 hours, and more preferably 6-8 hours. In the present invention, the degradation reaction is preferably carried out under stirring, and the present invention has no special requirement for the specific implementation process of the stirring. In a specific embodiment of the invention, the degradation reaction is carried out in a reaction vessel.

According to the invention, the waste polyurethane is degraded through the first alcoholysis agent, the second alcoholysis agent, the alcoholysis assistant agent and the phosphorus flame retardant, and the obtained degraded polyol contains condensed ring and/or aromatic ring polyols, and can form a cross-linked network structure with isocyanate compounds, so that the compression strength and the heat insulation performance of the halogen-free flame retardant foam material are improved; in the degradation reaction process of the waste polyurethane, the DOPO reaction type flame retardant with a dicarboxyl or dihydroxyl structure can participate in the crosslinking reaction in the alcoholysis process of the waste polyurethane, and is combined with the main chain or branched chain of the polyol polymer through the polymerization reaction with the alcoholysis product of the waste polyurethane, so that the flame retardant is not migrated, and the flame retardant effect and the physical and mechanical properties are kept for a long time; meanwhile, the graphene oxide nucleating agent promotes the foaming of polyurethane to obtain cells with small diameter and large number, so that the foam material has excellent thermal and mechanical properties.

After the degradation reaction, the obtained degradation reaction system is preferably subjected to post-treatment to obtain the degradation polyol; in the present invention, the post-treatment preferably comprises: carrying out solid-liquid separation, washing and drying on the degradation reaction system in sequence; the invention has no special requirement on the specific implementation mode of the solid-liquid separation, the invention preferably washes the liquid product of the solid-liquid separation, unreacted raw materials dissolved in water in the liquid product are removed by washing, in the invention, the washing frequency is preferably 3-5 times, and the mass ratio of the mass of the water to the mass of the liquid product is preferably (1-2): 1; the organic phase after being washed by water is preferably dried, in the invention, the drying is preferably rotary evaporation drying, in the invention, unreacted raw materials with low boiling points in the organic phase are preferably removed by drying, in the invention, the temperature of the rotary evaporation drying is preferably 120-145 ℃, in the invention, the time of the rotary evaporation drying is not particularly required, and the rotary evaporation drying is finished when no condensation product exists.

And after the degraded polyol is obtained, mixing the component A and an isocyanate compound (hereinafter referred to as second mixing) for foaming to obtain the halogen-free flame-retardant foam material, wherein the component A comprises the degraded polyol, a chain extender, a foaming agent, a catalyst and a stabilizer.

In the present invention, the a component comprises a spreading ligation; in the present invention, the chain extender preferably includes one or more of alcohol compounds, amine compounds, acid anhydride compounds, sucrose and glucose; the alcohol compound preferably comprises one or more of glycerol, diethylene glycol, triethylene glycol and diethylaminoethanol; the amine compound preferably comprises dimethylthiotoluenediamine and/or triethanolamine; the acid anhydride-based compound preferably includes dicarboxylic anhydride and/or acetic anhydride, and in the present invention, the chain extender more preferably includes triethanolamine or acetic anhydride.

In the present invention, the a component includes a foaming agent; the blowing agent preferably comprises one or more of an alkane, a fluoroalkane, a fluorochloroalkane, N-azobisisobutyronitrile, dicyandiamide, dimethyl ether, azodicarbonamide and water, the alkane preferably comprises one or more of a linear alkane and a cycloalkane, and more preferably comprises one or more of N-butane, propane-butane and cyclopentane; the fluoroalkanes preferably comprise 1,1,1,3, 3-pentafluorobutane and/or 1,1,2, 2-tetrafluoroethane, and the fluorochloroalkanes preferably comprise one or more of 1, 1-dichloro-1-fluoroethane; in the present invention, the blowing agent more preferably comprises cyclopentane or N, N-azobisisobutyronitrile.

In the present invention, the a component includes a catalyst; the catalyst preferably comprises one or more of amine compounds, ether compounds, oxazine compounds and tin compounds; the amine compound preferably comprises one or more of dimethylethanolamine, N', N "-pentamethyldiethylenetriamine, triethylenediamine, pentamethyldiethylenetriamine and N, N-dimethylethanolamine; the ether compound preferably comprises dimethylaminoethyl ether and/or 2, 2' -dimorpholinodiethyl ether; the oxazine compound is preferably tris (dimethylaminopropyl) hexahydrotriazine and/or N, N-dimethylpiperazine; the tin-based compound preferably includes organotin; in the present invention, the catalyst more preferably comprises organotin or dimethylaminoethyl ether.

In the present invention, the A component comprises a stabilizer; the stabilizer preferably comprises silicone oil; in the invention, the silicone oil preferably comprises one or more of silicone oil L-600, silicone oil SE-232, silicone oil CGY-5, silicone oil DC-193, silicone oil SC-154 and silicone oil SC-155; in the present invention, the stabilizer is more preferably one or more of silicone oil L-600, silicone oil SD-601 and silicone oil CGY-5.

In the invention, the mass ratio of the degradation polyol to the foaming agent in the component A is preferably 1 (0.5-3.5), and more preferably 1 (1.5-3).

In the component A, the mass ratio of the chain extender, the foaming agent, the catalyst and the stabilizer is preferably (0.1-10): (5-35): (0.1-10), and more preferably (1-8): (10-30): (0.5-5).

In the present invention, the a component preferably further includes a polyether polyol; in the present invention, the polyether polyol preferably comprises one or more of polyether polyol GR-635C, polyether polyol GR-4110A, polyether polyol GR-4110G, polyether polyol GR-450A, polyether polyol GR-649, polyether polyol GR-8340A, polyether polyol GR-835G, polyether polyol GRA-6360 and polyether polyol PED A-1500; in a specific embodiment of the present invention, the polyether polyol is preferably polyether polyol 4110A.

In the present invention, the mass ratio of the degradation polyol to the polyether polyol is preferably 1 (2-3), and more preferably 1 (2.2-2.5).

In the invention, the preparation method of the component A comprises the following steps:

the degraded polyol, the polyether polyol, the chain extender, the blowing agent, the catalyst and the stabilizer are mixed (hereinafter referred to as third mixing) to obtain a component a.

In the present invention, the third mixing is preferably carried out under stirring, and the present invention has no particular requirement on the specific implementation process of the stirring.

In the present invention, the isocyanate-based compound preferably includes a polyisocyanate-based compound; the polyisocyanate compound preferably comprises one or more of diisocyanate compounds, PAPI-27 and PAPI-135C; in the present invention, the diisocyanate-based compound preferably includes one or more of diphenylmethane diisocyanate, tolylene diisocyanate and hexamethylene diisocyanate, and the diphenylmethane diisocyanate preferably includes one or more of MDI-100LL, MDI-100HL, MR-200, M200, 44V20, M20S and 5005; the toluene diisocyanate preferably comprises one or more of TDI80, TDI20 and TDI 100; in the present invention, the polyisocyanate-based compound more preferably includes one or more of MR-200, M200 and PAPI-27.

In the present invention, the mass ratio of the degraded polyol to the isocyanate-based compound in the a component is preferably 1: (4-5), more preferably 1: (4.5-4.9).

In the invention, the second mixing is preferably carried out under the condition of stirring, and the invention has no special requirement on the specific implementation process of stirring so as to realize uniform mixing of the degradation raw materials.

In the present invention, the temperature of the foaming is preferably room temperature, and the foaming is preferably stopped when the mixture shows a milky white product. In the present invention, the foaming is preferably carried out under stirring, and the present invention has no particular requirement for the specific implementation of the stirring.

The invention provides the technologyThe apparent density of the halogen-free flame-retardant foam material prepared by the preparation method is 36.17-38.28 kg/m³。

The invention provides the application of the halogen-free flame-retardant foam material in the technical scheme in automobile manufacturing, transportation, civil construction, light industry, textile, electromechanics or petrochemical industry.

In the invention, the application specifically uses the halogen-free flame-retardant foam material in the technical scheme as a fireproof material in automobile manufacturing, transportation, civil construction, light industry, textile, electromechanics or petrochemical industry.

In order to further illustrate the present invention, the following embodiments are described in detail, but they should not be construed as limiting the scope of the present invention.

Example 1

100g of waste polyurethane foam, 40g of ethanolamine, 59g of sorbitol, 1g of cyclohexylamine, 1g of DOPO reaction type flame retardant (formula I) and 3g of graphene oxide (particle size of 10 mu m) are mixed, stirred for 5 hours at 160 ℃, cooled to room temperature, filtered, washed for 3 times, and then dried by rotary evaporation at 120 ℃ to obtain the degraded polyol.

10g of degraded polyol, 20g of polyether polyol 4110, 3g of silicone oil CGY-5, 0.2g of triethanolamine, 0.2g of organic tin and 15g of cyclopentane are uniformly stirred to be used as white materials, then the white materials are stirred with 48.40g of PAPI-27 for 18s to foam, and the halogen-free flame retardant foam material is obtained after cooling.

Example 2

Mixing 100g of waste polyurethane foam, 40g of propanolamine, 58g of pentanediol, 2g of cyclohexylamine, 2g of DOPO reaction type flame retardant (formula II) and 3g of graphene oxide (with the particle size of 10 mu m), stirring at 150 ℃ for 2.5 hours, cooling to room temperature, filtering, washing for 3 times, and then drying at 120 ℃ by rotary evaporation to obtain the degraded polyol.

10g of degraded polyol, 20g of polyether polyol 4110, 3g of silicone oil CGY-5, 0.2g of triethanolamine, 0.2g of organic tin and 15g of cyclopentane are uniformly stirred to be used as white materials, then the white materials are stirred with 48.40g of PAPI-27 for 18s to foam, and the halogen-free flame retardant foam material is obtained after cooling.

Example 3

Mixing 100g of waste polyurethane foam, 50g of ethanolamine, 47g of butynediol, 3g of cyclohexylamine, 3g of DOPO reaction type flame retardant (formula III) and 3g of graphene oxide (particle size is 10 micrometers), stirring at 165 ℃ for 6 hours, cooling to room temperature, filtering, washing for 3 times, and then drying at 120 ℃ by rotary evaporation to obtain the degraded polyol.

10g of degraded polyol, 20g of polyether polyol 4110, 3g of silicone oil CGY-5, 0.2g of triethanolamine, 0.2g of organic tin and 15g of cyclopentane are uniformly stirred to be used as white materials, then the white materials are stirred with 48.40g of PAPI-27 for 18s to foam, and the halogen-free flame retardant foam material is obtained after cooling.

Example 4

Mixing 100g of waste polyurethane foam, 40g of propanolamine, 56g of propylene glycol, 4g of cyclohexylamine, 4g of DOPO reaction type flame retardant (formula VI) and 3g of graphene oxide (with the particle size of 20 mu m), stirring at 155 ℃ for 5 hours, cooling to room temperature, filtering, washing for 3 times, and then drying at 120 ℃ by rotary evaporation to obtain the degraded polyol.

10g of degraded polyol, 20g of polyether polyol 4110, 3g of silicone oil CGY-5, 0.2g of triethanolamine, 0.2g of organic tin and 15g of cyclopentane are uniformly stirred to be used as white materials, then the white materials are stirred with 48.40g of PAPI-27 for 18s to foam, and the halogen-free flame retardant foam material is obtained after cooling.

Example 5

Mixing 100g of waste polyurethane foam, 35g of ethanolamine, 60g of ethylene glycol, 5g of cyclohexylamine, 5g of DOPO reaction type flame retardant (formula V) and 3g of graphene oxide (particle size is 5 microns), stirring for 5 hours at 170 ℃, cooling to room temperature, filtering, washing for 3 times, and then drying by rotary evaporation at 120 ℃ to obtain the degraded polyol.

10g of degraded polyol, 20g of polyether polyol 4110, 3g of silicone oil CGY-5, 0.2g of triethanolamine, 0.2g of organic tin and 15g of cyclopentane are uniformly stirred to be used as white materials, then the white materials are stirred with 48.40g of PAPI-27 for 18s to foam, and the halogen-free flame retardant foam material is obtained after cooling.

Example 6

Mixing 100g of waste polyurethane foam, 40g of ethanolamine, 60g of ethylene glycol, 1g of cyclohexylamine, 5g of DOPO reaction type flame retardant (formula V) and 3g of graphene oxide (with the particle size of 0.5 mu m), stirring for 5 hours at 170 ℃, cooling to room temperature, filtering, washing for 3 times, and then drying at 120 ℃ by rotary evaporation to obtain the degraded polyol.

10g of degraded polyol, 20g of polyether polyol 4110, 3g of silicone oil CGY-5, 0.2g of triethanolamine, 0.2g of organic tin and 15g of cyclopentane are uniformly stirred to be used as white materials, then the white materials are stirred with 48.40g of PAPI-27 for 18s to foam, and the halogen-free flame retardant foam material is obtained after cooling.

Comparative example 1

100g of waste polyurethane foam, 40g of ethanolamine, 60g of ethylene glycol and 1g of cyclohexylamine are mixed, stirred for 5 hours at the temperature of 170 ℃, cooled to room temperature, filtered, washed with water for 3 times, and then dried by rotary evaporation at the temperature of 125 ℃ to obtain the degraded polyol.

10g of degraded polyol, 20g of polyether polyol 4110, 3g of silicone oil CGY-5, 0.2g of triethanolamine, 0.2g of organic tin and 15g of cyclopentane are uniformly stirred to be used as white materials, then the white materials are stirred with 48.40g of PAPI-27 for 18s to foam, and the halogen-free flame retardant foam material is obtained after cooling.

Comparative example 2

100g of waste polyurethane foam, 40g of ethanolamine, 60g of ethylene glycol, 1g of cyclohexylamine and 3g of graphene oxide (particle size of 10 mu m) are mixed, stirred for 5 hours at 170 ℃, cooled to room temperature, filtered, washed for 3 times, and then dried by rotary evaporation at 120 ℃ to obtain the degraded polyol.

10g of degraded polyol, 20g of polyether polyol 4110, 3g of silicone oil CGY-5, 0.2g of triethanolamine, 0.2g of organic tin and 15g of cyclopentane are uniformly stirred to be used as white materials, then the white materials are stirred with 48.40g of PAPI-27 for 18s to foam, and the halogen-free flame retardant foam material is obtained after cooling.

Comparative example 3

Mixing 100g of waste polyurethane foam with 40g of ethanolamine, 60g of ethylene glycol, 1g of cyclohexylamine and 5g of DOPO reaction type flame retardant (formula V), stirring for 5 hours at 170 ℃, cooling to room temperature, filtering, washing for 3 times, and then drying by rotary evaporation at 120 ℃ to obtain the degraded polyol.

10g of degraded polyol, 20g of polyether polyol 4110, 3g of silicone oil CGY-5, 0.2g of triethanolamine, 0.2g of organic tin and 15g of cyclopentane are uniformly stirred to be used as white materials, then the white materials are stirred with 48.40g of PAPI-27 for 18s to foam, and the halogen-free flame retardant foam material is obtained after cooling.

Test example 1

The performances of the halogen-free flame-retardant foam materials prepared in the examples 1 to 5 and the comparative examples 1 to 3 are tested, the test results are shown in Table 1, and it can be seen from the results of Table 1 that the halogen-free flame-retardant foam material prepared by the invention has the compression strength of 0.23 to 0.25MPa and the apparent density of 36.17 to 38.28kg/m compared with the comparative document 1³The LOI index is 25.1-27.6%, which is higher than the national standard, and the degradation method provided by the invention saves materials and obtains obvious economic benefit.

TABLE 1 Properties of halogen-free flame-retardant foams prepared in examples 1 to 5 and comparative examples 1 to 3

Sample numbering	Density kg/m3	Compressive strength/Mpa	LOI/％
				Example 1	36.17	0.25	26.1
Example 2	37.72	0.25	25.1
				Example 3	36.79	0.25	27.6
Example 4	38.28	0.23	26.1
				Example 5	36.96	0.24	26.4
Comparative example 1	34.65	0.19	20.7
				Comparative example 2	35.25	0.20	21.1
Comparative example 3	35.52	0.21	23.2

Although the present invention has been described in detail with reference to the above embodiments, it is only a part of the embodiments of the present invention, not all of the embodiments, and other embodiments can be obtained without inventive step according to the embodiments, and the embodiments are within the scope of the present invention.