A method for preparing environmentally friendly flame-retardant expandable polystyrene

Abstract

The present application relates to the field of expandable polystyrene synthesis technology, and specifically discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene. The method for preparing environmentally friendly flame-retardant expandable polystyrene comprises the following steps: adding pure water, water-based auxiliary materials, styrene and oil-based auxiliary materials in a reaction kettle in sequence, heating and keeping warm by steam, adding dispersant B and foaming agent after low-temperature polymerization, then heating to enter high-temperature polymerization, cooling and discharging after polymerization. The preparation method of the present application can effectively reduce water pollution, thereby being more environmentally friendly and energy-saving.

Description

Technical Field

[0001] The present application relates to the field of expandable polystyrene synthesis technology, and more specifically, to a method for preparing environmentally friendly flame-retardant expandable polystyrene. Background Art

[0002] Expandable polystyrene (EPS) is made from pure water, styrene, benzoyl peroxide, tert-butyl perbenzoate, pentane, structural regulator, flame retardant (methyl octabromoether, brominated SBS) and other raw materials through stirring, heating, suspension polymerization, washing, screening and other steps. Expandable polystyrene beads containing foaming agent can be made into foam plastic products through pre-foaming, aging and foam molding. Foamed polystyrene foam plastic products are currently extremely valuable insulation, heat insulation, thermal insulation and packaging cushioning materials. Polystyrene foam has low water absorption, heat insulation, excellent dielectric properties and high mechanical strength.

[0003] Currently, the expandable polystyrene products on the market are affected by auxiliary factors such as flame retardants, initiators and stabilizers. Most of the products have many disadvantages such as high residue, low conversion rate and unstable flame retardancy. In particular, the auxiliary materials that act on the system externally, such as sodium dodecylbenzene sulfonate and sodium sulfate, have a great impact on water pollution, resulting in high sewage treatment costs. Summary of the invention

[0004] In order to reduce the pollution of water quality caused by auxiliary materials in the system in the expandable polystyrene synthesis process and reduce the cost of sewage treatment, the present application provides a method for preparing environmentally friendly flame-retardant expandable polystyrene, which adopts the following technical solution:

[0005] A method for preparing environmentally friendly flame-retardant expandable polystyrene comprises the following steps:

[0006] S1. Add 110 parts by weight of pure water into the reaction kettle; add the following aqueous auxiliary materials and stir evenly: 0.06-0.08 parts by weight of dispersant A, 0.0014-0.0018 parts by weight of reagent A, and 0.001-0.0012 parts by weight of reagent B;

[0007] S2, add 100 parts by weight of styrene; add the following oily auxiliary materials and stir evenly: 0.25-0.55 parts by weight of initiator A, 0.03-0.08 parts by weight of initiator B, 0.2-0.5 parts by weight of initiator C, 0.6-0.9 parts by weight of flame retardant, 0.2-0.6 parts by weight of plasticizer, 0.005-0.008 parts by weight of stabilizer and 0.1-0.2 parts by weight of nucleating agent;

[0008] S3, heating to 88-90°C and reacting for 5-6 hours;

[0009] S4, first add 0.2-0.3 parts by weight of dispersant B, and then add 0.5-1.2 parts by weight of foaming agent;

[0010] S5, heating to 118-130°C, reacting for 2.5-5 hours;

[0011] S6, cooling and discharging.

[0012] By adopting the above technical solution, the auxiliary materials of the reaction system are changed to make the system more stable and more environmentally friendly; the residual substances after the reaction are reduced, and the sewage treatment is more efficient and energy-saving; the polymerization and impregnation are completed in the same kettle at one time, thereby saving production time and shortening the production cycle.

[0013] Preferably, the initiator A is one or more of azobisisobutyronitrile, benzoyl peroxide and tert-butylperoxy-2-ethylhexyl carbonate.

[0014] Preferably, the initiator B is one or more of dicumyl peroxide, bis(4-tert-butylcyclohexyl)peroxydicarbonate and hexadecyl ester.

[0015] Preferably, the initiator C is one or more of tert-butyl perbenzoate, tert-butyl peroxyneodecanoate and tert-butyl peroxycarbonate-2-ethylhexyl ester.

[0016] Preferably, the foaming agent is one or more of n-pentane, isopentane and neopentane.

[0017] Preferably, the reagent A is one or more of polyvinyl alcohol, carboxymethyl cellulose and ethyl cellulose.

[0018] Preferably, the reagent B is one of potassium pyrosulfite or potassium persulfate.

[0019] Preferably, the foaming agent is one or more of n-pentane, isopentane and neopentane.

[0020] Preferably, the oily auxiliary material further comprises 0.5 to 1.5 parts by weight of a reinforced modified composite powder, wherein the reinforced modified composite powder comprises modified graphene oxide, calcium metaborate and polyethylene glycol monomethyl ether.

[0021] By adopting the above technical scheme, polyethylene glycol monomethyl ether is used as a connector between modified graphene oxide and calcium metaborate, and the molecular chain on the surface of modified graphene oxide and the interlayer structure of calcium metaborate itself are utilized to enable the two to be tightly connected, thereby allowing the modified graphene oxide to be affected by the physical properties of calcium metaborate and improve its dispersion performance.

[0022] Preferably, the enhanced modified composite powder is prepared by the following steps: mixing calcium metaborate with oleic acid mixed with polyethylene glycol monomethyl ether and ball milling, and then adding modified graphene oxide and continuing to mix and ball mill, thereby obtaining the enhanced modified composite powder.

[0023] By adopting the above technical scheme, oleic acid is first used as a medium to aggregate polyethylene glycol monomethyl ether and calcium metaborate, and at the same time the calcium metaborate is crushed and refined, and then modified graphene oxide is added, and the crushed and refined calcium metaborate is combined with the modified graphene oxide through the polyethylene glycol monomethyl ether during the ball milling process, thereby improving the dispersion performance of the modified graphene oxide.

[0024] Preferably, the modified graphene oxide is prepared from graphene oxide, unsaturated fatty acid and conjugated diene.

[0025] By adopting the above technical scheme, graphene oxide is first combined with unsaturated fatty acids to carry out acyl chlorination reaction, thereby improving the compatibility of modified graphene oxide in oily auxiliary materials and making it easier for modified graphene oxide to be dispersed in oily auxiliary materials. Then, unsaturated fatty acids on graphene oxide and conjugated dienes are reacted to form graphene oxide containing cyclic unsaturated fatty acids, thereby improving the overall stability of modified graphene oxide while improving the dispersion performance of graphene oxide.

[0026] Preferably, the modified graphene oxide is prepared by the following steps: S1, subjecting graphene oxide to acyl chloride reaction with unsaturated fatty acid to obtain an intermediate product; S2, subjecting the intermediate product to a reaction with a conjugated diene to generate the final modified graphene oxide.

[0027] By adopting the above technical scheme, the graphene oxide is first modified with unsaturated fatty acids to improve its dispersibility in oily auxiliary materials, and then the unsaturated fatty acids on the graphene oxide are closed-loop, thereby improving the stability of the unsaturated fatty acids on the graphene oxide.

[0028] Preferably, the expandable polystyrene is used to prepare a foam board, and the preparation steps are: subjecting the environmentally friendly flame-retardant expandable polystyrene to pre-expansion, aging and molding processes to obtain a foam board.

[0029] In summary, this application has the following beneficial effects:

[0030] 1. Since the present application uses a more advanced and stable emulsifier to replace the original sodium dodecylbenzene sulfonate to reduce water pollution, the early suspension polymerization is more stable, and the residual substances after the reaction are reduced, thereby reducing the later defoaming agent, and the sewage treatment is more efficient and energy-saving.

[0031] 2. The preparation method of the present application improves the conversion rate, reduces the residual styrene monomer, makes the product structure more stable, and reduces the high-temperature residual monomer from the original 0.3% to 0.05%, greatly improving the conversion rate of the product.

[0032] 3. The effective particle concentration of the preparation method of the present application is increased from the original 65% to 75%, thereby increasing product revenue.

[0033] 4. The preparation method of the present application eliminates toluene, thus eliminating its residue in the product.

[0034] 5. In the present application, graphene oxide is preferably used to improve the strength of the prepared plate, and the graphene oxide is doubly modified at the same time, so that the doubly modified graphene oxide is evenly dispersed, which is more conducive to improving the performance of the plate. DETAILED DESCRIPTION

[0035] The present application is further described in detail below with reference to the embodiments.

[0036] Preparation Example

[0037] Preparation Example 1

[0038] This preparation example discloses a modified graphene oxide, which is prepared by the following steps:

[0039] S1. Unsaturated fatty acid functionalized graphene oxide: Take 0.5g of graphene oxide and dissolve it in 150mL of dehydrated DMF solvent. After evenly dispersing, transfer it to a 250mL four-necked flask equipped with a dry tail pipe and an exhaust removal device, add 20mL of acrylic acid, 1mg of hydroquinone inhibitor, 30mg of triethylamine, and then slowly add 30mL of dichlorothionyl, stir magnetically, and pass nitrogen to prevent acrylic acid and product from self-polymerization. After reacting in an ice bath for 2h, let it react at room temperature overnight. After the reaction is completed, filter to remove a small amount of black insoluble matter, wash the filtrate with water, and the brown product is deposited at the bottom. Let it stand and pour off the supernatant, wash it repeatedly with water, and then centrifuge it at 10,000 rpm for 3 times to remove the small molecular byproducts and a small amount of self-polymerized acrylic acid wrapped in the product, and freeze-dry at -40℃ to obtain a brown intermediate product;

[0040] S2, conjugated diene stabilized graphene oxide: add 2g of the intermediate product obtained in S1, 2g of butadiene and 25mL of anhydrous xylene to a 50mL round-bottom flask, connect a reflux condenser, and heat to reflux at 140℃ for 25min. Shake the crystals precipitated on the edge of the liquid surface, continue heating for 5min, and stop heating. When it does not reflux, filter it while hot through a preheated Buchner funnel, cool the filtrate, separate the solid product by suction, and dry it in a vacuum dryer to obtain modified graphene oxide.

[0041] Preparation Example 2

[0042] This preparation example discloses a modified graphene oxide, which is prepared by the following steps:

[0043] S1. Unsaturated fatty acid functionalized graphene oxide: Take 0.5g of graphene oxide and dissolve it in 150mL of dehydrated DMF solvent. After evenly dispersing, transfer it to a 250mL four-necked flask equipped with a dry tail pipe and an exhaust gas removal device, add 20mL of linoleic acid, 1mg of hydroquinone inhibitor, 30mg of triethylamine, and then slowly add 30mL of dichlorothionyl, stir magnetically, and pass nitrogen to prevent acrylic acid and product from self-polymerizing. After reacting in an ice bath for 2h, let it react at room temperature overnight. After the reaction is completed, filter to remove a small amount of black insoluble matter, wash the filtrate with water, and the brown product is deposited at the bottom. Let it stand and pour off the supernatant, wash it repeatedly with water, and then centrifuge it at 10,000 rpm for 3 times to remove the small molecular byproducts and a small amount of self-polymerized acrylic acid wrapped in the product, and freeze-dry at -40℃ to obtain a brown intermediate product;

[0044] S2, conjugated diene stabilized graphene oxide: add 2g of the intermediate product obtained in S1, 2g of butadiene and 25mL of anhydrous xylene to a 50mL round-bottom flask, connect a reflux condenser, and heat to reflux at 140°C for 25min. Shake the crystals precipitated on the edge of the liquid surface, continue heating for 5min, and stop heating. When it does not reflux, filter it while hot through a preheated Buchner funnel, cool the filtrate, separate the solid product by suction, and dry it in a vacuum dryer to obtain modified graphene oxide.

[0045] Preparation Example 3

[0046] This preparation example discloses a modified graphene oxide, which is prepared by the following steps:

[0047] S1. Unsaturated fatty acid functionalized graphene oxide: Take 0.5g of graphene oxide and dissolve it in 150mL of dehydrated DMF solvent. After evenly dispersing, transfer it to a 250mL four-necked flask equipped with a dry tail pipe and an exhaust removal device, add 20mL of acrylic acid, 1mg of hydroquinone inhibitor, 30mg of triethylamine, and then slowly add 30mL of dichlorothionyl, stir magnetically, and pass nitrogen to prevent acrylic acid and product from self-polymerization. After reacting in an ice bath for 2h, let it react at room temperature overnight. After the reaction is completed, filter to remove a small amount of black insoluble matter, wash the filtrate with water, and the brown product is deposited at the bottom. Let it stand and pour off the supernatant, wash it repeatedly with water, and then centrifuge it at 10,000 rpm for 3 times to remove the small molecular byproducts and a small amount of self-polymerized acrylic acid wrapped in the product, and freeze-dry at -40℃ to obtain a brown intermediate product;

[0048] S2, conjugated diene stabilized graphene oxide: add 2g of the intermediate product obtained in S1, 2g of 1,4-pentadiene and 25mL of anhydrous xylene to a 50mL round-bottom flask, connect a reflux condenser, and heat to reflux at 140°C for 25min. Shake the crystals precipitated on the edge of the liquid surface, continue heating for 5min, and stop heating. When it does not reflux, filter it while hot through a preheated Buchner funnel, cool the filtrate, separate the solid product by suction, and dry it in a vacuum dryer to obtain modified graphene oxide.

[0049] Preparation Example 4

[0050] This preparation example discloses a reinforced modified composite powder, which is prepared by the following steps:

[0051] S1, mix 2 mL of polyethylene glycol monomethyl ether and 8 mL of oleic acid, then mix with 4 g of calcium metaborate and ball mill for 10 h;

[0052] S2. Add 1 g of the modified graphene oxide obtained in Preparation Example 1 and continue ball milling for 10 hours to obtain a reinforced modified composite powder.

[0053] Preparation Example 5

[0054] This preparation example discloses a reinforced modified composite powder, which is prepared by the following steps:

[0055] S1, mix 2 mL of polyethylene glycol monomethyl ether and 8 mL of oleic acid, then mix with 4 g of calcium metaborate and ball mill for 10 h;

[0056] S2. Add 1 g of the modified graphene oxide obtained in Preparation Example 2 and continue ball milling for 10 hours to obtain a reinforced modified composite powder.

[0057] Preparation Example 6

[0058] This preparation example discloses a reinforced modified composite powder, which is prepared by the following steps:

[0059] S1, mix 2 mL of polyethylene glycol monomethyl ether and 8 mL of oleic acid, then mix with 4 g of calcium metaborate and ball mill for 10 h;

[0060] S2. Add 1 g of the modified graphene oxide obtained in Preparation Example 3 and continue ball milling for 10 hours to obtain a reinforced modified composite powder.

[0061] Preparation Example 7

[0062] This preparation example discloses a reinforced modified composite powder, which is prepared by the following steps:

[0063] S1. Mix 10 mL of oleic acid and 4 g of calcium metaborate and ball mill for 10 h;

[0064] S2. Add 1 g of the modified graphene oxide obtained in Preparation Example 3 and continue ball milling for 10 hours to obtain a reinforced modified composite powder.

[0065] Example

[0066] Example 1

[0067] This embodiment discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene, which comprises the following steps:

[0068] S1. Add 110 kg of pure water into the reactor; add the following aqueous excipients and stir evenly: 0.06 kg of dispersant A, 0.0014 kg of reagent A, and 0.001 kg of reagent B;

[0069] S2, add 100kg of styrene; add the following oily auxiliary materials and stir evenly: 0.25kg of initiator A, 0.03kg of initiator B, 0.2kg of initiator C, 0.6kg of flame retardant, 0.2kg of plasticizer, 0.005kg of stabilizer and 0.1kg of nucleating agent;

[0070] S3, heating to 88°C and reacting for 5 hours;

[0071] S4, first add 0.2kg dispersant B, then add 0.5kg foaming agent;

[0072] S5, heating to 118°C, reacting for 2.5 hours;

[0073] S6, cooling and discharging the material to obtain environmentally friendly flame retardant expandable polystyrene.

[0074] In this embodiment, dispersant A is active calcium phosphate; reagent A is polyvinyl alcohol; reagent B is potassium pyrosulfite; initiator A is azobisisobutyronitrile; initiator B is bis(4-tert-butylcyclohexyl) peroxydicarbonate; initiator C is tert-butyl perbenzoate; the flame retardant is methyl octabromoether; the plasticizer is epoxy resin; the stabilizer is a mixture of magnesium phosphate and zinc phosphate in a weight ratio of 1:1; the nucleating agent is polyethylene wax; the dispersant B is a mixture of calcium phosphate and calcium carbonate in a weight ratio of 1:1; and the foaming agent is isopentane.

[0075] Example 2

[0076] This embodiment discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene, which comprises the following steps:

[0077] S1. Add 110 kg of pure water into the reactor; add the following aqueous excipients and stir evenly: 0.07 kg of dispersant A, 0.0016 kg of reagent A, and 0.0011 kg of reagent B;

[0078] S2, add 100kg of styrene; add the following oily auxiliary materials and stir evenly: 0.4kg initiator A, 0.055kg initiator B, 0.35kg initiator C, 0.75kg flame retardant, 0.4kg plasticizer, 0.0065kg stabilizer and 0.15kg nucleating agent;

[0079] S3, heating to 89°C and reacting for 5.5 hours;

[0080] S4, first add 0.25kg dispersant B, then add 0.75kg foaming agent;

[0081] S5, heating to 124°C, reacting for 3.5 hours;

[0082] S6, cooling and discharging the material to obtain environmentally friendly flame retardant expandable polystyrene.

[0083] In this embodiment, dispersant A is active calcium phosphate; reagent A is carboxymethyl cellulose; reagent B is potassium persulfate; initiator A is benzoyl peroxide; initiator B is diisopropylbenzene peroxide; initiator C is tert-butyl peroxycarbonate-2-ethylhexyl ester; the flame retardant is brominated styrene butadiene copolymer; the plasticizer is epoxy resin; the stabilizer is a mixture of magnesium phosphate and zinc phosphate in a weight ratio of 1:1; the nucleating agent is polyethylene wax; the dispersant B is a mixture of calcium phosphate and calcium carbonate in a weight ratio of 1:1; and the foaming agent is n-pentane.

[0084] Example 3

[0085] This embodiment discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene, which comprises the following steps:

[0086] S1. Add 110 kg of pure water into the reactor; add the following aqueous auxiliary materials and stir evenly: 0.08 kg of dispersant A, 0.0018 kg of reagent A, and 0.0012 kg of reagent B;

[0087] S2, add 100kg of styrene; add the following oily auxiliary materials and stir evenly: 0.55kg of initiator A, 0.08kg of initiator B, 0.5kg of initiator C, 0.9kg of flame retardant, 0.6kg of plasticizer, 0.008kg of stabilizer and 0.2kg of nucleating agent;

[0088] S3, heating to 90°C and reacting for 6 hours;

[0089] S4, first add 0.3kg dispersant B, then add 1.2kg foaming agent;

[0090] S5, heating to 130°C and reacting for 5 hours;

[0091] S6, cooling and discharging the material to obtain environmentally friendly flame retardant expandable polystyrene.

[0092] In this embodiment, dispersant A is active calcium phosphate; reagent A is carboxyethyl cellulose; reagent B is potassium persulfate; initiator A is tert-butyl peroxy-2-ethylhexyl carbonate; initiator B is hexadecyl ester; initiator C is tert-butyl peroxyneodecanoate; the flame retardant is a mixture of brominated styrene butadiene copolymer and methyl octabromoether in a ratio of 1:1 by weight; the plasticizer is epoxy resin; the stabilizer is a mixture of magnesium phosphate and zinc phosphate in a ratio of 1:1 by weight; the nucleating agent is polyethylene wax; the dispersant B is a mixture of calcium phosphate and calcium carbonate in a ratio of 1:1 by weight; and the foaming agent is neopentane.

[0093] Example 4

[0094] This embodiment discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene, which comprises the following steps:

[0095] S1. Add 110 kg of pure water into the reactor; add the following aqueous excipients and stir evenly: 0.07 kg of dispersant A, 0.0016 kg of reagent A, and 0.0011 kg of reagent B;

[0096] S2, add 100kg of styrene; add the following oily auxiliary materials and stir evenly: 0.4kg initiator A, 0.055kg initiator B, 0.35kg initiator C, 0.75kg flame retardant, 0.4kg plasticizer, 0.0065kg stabilizer, 0.15kg nucleating agent and 0.5kg of the reinforced modified composite powder prepared in Preparation Example 4;

[0097] S3, heating to 89°C and reacting for 5.5 hours;

[0098] S4, first add 0.25kg dispersant B, then add 0.75kg foaming agent;

[0099] S5, heating to 124°C, reacting for 3.5 hours;

[0100] S6, cooling and discharging the material to obtain environmentally friendly flame retardant expandable polystyrene.

[0101] In this embodiment, dispersant A is active calcium phosphate; reagent A is carboxymethyl cellulose; reagent B is potassium persulfate; initiator A is benzoyl peroxide; initiator B is diisopropylbenzene peroxide; initiator C is tert-butyl peroxycarbonate-2-ethylhexyl ester; the flame retardant is brominated styrene butadiene copolymer; the plasticizer is epoxy resin; the stabilizer is a mixture of magnesium phosphate and zinc phosphate in a weight ratio of 1:1; the nucleating agent is polyethylene wax; the dispersant B is a mixture of calcium phosphate and calcium carbonate in a weight ratio of 1:1; and the foaming agent is n-pentane.

[0102] Example 5

[0103] This embodiment discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene, which comprises the following steps:

[0104] S1. Add 110 kg of pure water into the reactor; add the following aqueous excipients and stir evenly: 0.07 kg of dispersant A, 0.0016 kg of reagent A, and 0.0011 kg of reagent B;

[0105] S2, add 100kg of styrene; add the following oily auxiliary materials and stir evenly: 0.4kg initiator A, 0.055kg initiator B, 0.35kg initiator C, 0.75kg flame retardant, 0.4kg plasticizer, 0.0065kg stabilizer, 0.15kg nucleating agent and 1kg of the reinforced modified composite powder prepared in Preparation Example 4;

[0106] S3, heating to 89°C and reacting for 5.5 hours;

[0107] S4, first add 0.25kg dispersant B, then add 0.75kg foaming agent;

[0108] S5, heating to 124°C, reacting for 3.5 hours;

[0109] S6, cooling and discharging the material to obtain environmentally friendly flame retardant expandable polystyrene.

[0110] In this embodiment, dispersant A is active calcium phosphate; reagent A is carboxymethyl cellulose; reagent B is potassium persulfate; initiator A is benzoyl peroxide; initiator B is diisopropylbenzene peroxide; initiator C is tert-butyl peroxycarbonate-2-ethylhexyl ester; the flame retardant is brominated styrene butadiene copolymer; the plasticizer is epoxy resin; the stabilizer is a mixture of magnesium phosphate and zinc phosphate in a weight ratio of 1:1; the nucleating agent is polyethylene wax; the dispersant B is a mixture of calcium phosphate and calcium carbonate in a weight ratio of 1:1; and the foaming agent is n-pentane.

[0111] Example 6

[0112] This embodiment discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene, which comprises the following steps:

[0113] S1. Add 110 kg of pure water into the reactor; add the following aqueous excipients and stir evenly: 0.07 kg of dispersant A, 0.0016 kg of reagent A, and 0.0011 kg of reagent B;

[0114] S2, add 100kg of styrene; add the following oily auxiliary materials and stir evenly: 0.4kg initiator A, 0.055kg initiator B, 0.35kg initiator C, 0.75kg flame retardant, 0.4kg plasticizer, 0.0065kg stabilizer, 0.15kg nucleating agent and 1.5kg of the reinforced modified composite powder prepared in Preparation Example 4;

[0115] S3, heating to 89°C and reacting for 5.5 hours;

[0116] S4, first add 0.25kg dispersant B, then add 0.75kg foaming agent;

[0117] S5, heating to 124°C, reacting for 3.5 hours;

[0118] S6, cooling and discharging the material to obtain environmentally friendly flame retardant expandable polystyrene.

[0119] In this embodiment, dispersant A is active calcium phosphate; reagent A is carboxymethyl cellulose; reagent B is potassium persulfate; initiator A is benzoyl peroxide; initiator B is diisopropylbenzene peroxide; initiator C is tert-butyl peroxycarbonate-2-ethylhexyl ester; the flame retardant is brominated styrene butadiene copolymer; the plasticizer is epoxy resin; the stabilizer is a mixture of magnesium phosphate and zinc phosphate in a weight ratio of 1:1; the nucleating agent is polyethylene wax; the dispersant B is a mixture of calcium phosphate and calcium carbonate in a weight ratio of 1:1; and the foaming agent is n-pentane.

[0120] Example 7

[0121] This embodiment discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene, which comprises the following steps:

[0122] S1. Add 110 kg of pure water into the reactor; add the following aqueous excipients and stir evenly: 0.07 kg of dispersant A, 0.0016 kg of reagent A, and 0.0011 kg of reagent B;

[0123] S2, add 100kg of styrene; add the following oily auxiliary materials and stir evenly: 0.4kg initiator A, 0.055kg initiator B, 0.35kg initiator C, 0.75kg flame retardant, 0.4kg plasticizer, 0.0065kg stabilizer, 0.15kg nucleating agent and 1kg of the reinforced modified composite powder prepared in Preparation Example 5;

[0124] S3, heating to 89°C and reacting for 5.5 hours;

[0125] S4, first add 0.25kg dispersant B, then add 0.75kg foaming agent;

[0126] S5, heating to 124°C, reacting for 3.5 hours;

[0127] S6, cooling and discharging the material to obtain environmentally friendly flame retardant expandable polystyrene.

[0128] In this embodiment, dispersant A is active calcium phosphate; reagent A is carboxymethyl cellulose; reagent B is potassium persulfate; initiator A is benzoyl peroxide; initiator B is diisopropylbenzene peroxide; initiator C is tert-butyl peroxycarbonate-2-ethylhexyl ester; the flame retardant is brominated styrene butadiene copolymer; the plasticizer is epoxy resin; the stabilizer is a mixture of magnesium phosphate and zinc phosphate in a weight ratio of 1:1; the nucleating agent is polyethylene wax; the dispersant B is a mixture of calcium phosphate and calcium carbonate in a weight ratio of 1:1; and the foaming agent is n-pentane.

[0129] Example 8

[0130] This embodiment discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene, which comprises the following steps:

[0131] S1. Add 110 kg of pure water into the reactor; add the following aqueous excipients and stir evenly: 0.07 kg of dispersant A, 0.0016 kg of reagent A, and 0.0011 kg of reagent B;

[0132] S2, add 100kg of styrene; add the following oily auxiliary materials and stir evenly: 0.4kg initiator A, 0.055kg initiator B, 0.35kg initiator C, 0.75kg flame retardant, 0.4kg plasticizer, 0.0065kg stabilizer, 0.15kg nucleating agent and 1kg of the reinforced modified composite powder prepared in Preparation Example 6;

[0133] S3, heating to 89°C and reacting for 5.5 hours;

[0134] S4, first add 0.25kg dispersant B, then add 0.75kg foaming agent;

[0135] S5, heating to 124°C, reacting for 3.5 hours;

[0136] S6, cooling and discharging the material to obtain environmentally friendly flame retardant expandable polystyrene.

[0137] In this embodiment, dispersant A is active calcium phosphate; reagent A is carboxymethyl cellulose; reagent B is potassium persulfate; initiator A is benzoyl peroxide; initiator B is diisopropylbenzene peroxide; initiator C is tert-butyl peroxycarbonate-2-ethylhexyl ester; the flame retardant is brominated styrene butadiene copolymer; the plasticizer is epoxy resin; the stabilizer is a mixture of magnesium phosphate and zinc phosphate in a weight ratio of 1:1; the nucleating agent is polyethylene wax; the dispersant B is a mixture of calcium phosphate and calcium carbonate in a weight ratio of 1:1; and the foaming agent is n-pentane.

[0138] Example 9

[0139] This embodiment discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene, which comprises the following steps:

[0140] S1. Add 110 kg of pure water into the reactor; add the following aqueous excipients and stir evenly: 0.07 kg of dispersant A, 0.0016 kg of reagent A, and 0.0011 kg of reagent B;

[0141] S2, add 100kg of styrene; add the following oily auxiliary materials and stir evenly: 0.4kg initiator A, 0.055kg initiator B, 0.35kg initiator C, 0.75kg flame retardant, 0.4kg plasticizer, 0.0065kg stabilizer, 0.15kg nucleating agent and 1kg of the reinforced modified composite powder prepared in Preparation Example 7;

[0142] S3, heating to 89°C and reacting for 5.5 hours;

[0143] S4, first add 0.25kg dispersant B, then add 0.75kg foaming agent;

[0144] S5, heating to 124°C, reacting for 3.5 hours;

[0145] S6, cooling and discharging the material to obtain environmentally friendly flame retardant expandable polystyrene.

[0146] In this embodiment, dispersant A is active calcium phosphate; reagent A is carboxymethyl cellulose; reagent B is potassium persulfate; initiator A is benzoyl peroxide; initiator B is diisopropylbenzene peroxide; initiator C is tert-butyl peroxycarbonate-2-ethylhexyl ester; the flame retardant is brominated styrene butadiene copolymer; the plasticizer is epoxy resin; the stabilizer is a mixture of magnesium phosphate and zinc phosphate in a weight ratio of 1:1; the nucleating agent is polyethylene wax; the dispersant B is a mixture of calcium phosphate and calcium carbonate in a weight ratio of 1:1; and the foaming agent is n-pentane.

[0147] Example 10

[0148] This embodiment discloses a method for preparing environmentally friendly flame-retardant expandable polystyrene, which comprises the following steps:

[0149] S1. Add 110 kg of pure water into the reactor; add the following aqueous excipients and stir evenly: 0.07 kg of dispersant A, 0.0016 kg of reagent A, and 0.0011 kg of reagent B;

[0150] S2, add 100 kg of styrene; add the following oily auxiliary materials and stir evenly: 0.4 kg initiator A, 0.055 kg initiator B, 0.35 kg initiator C, 0.75 kg flame retardant, 0.4 kg plasticizer, 0.0065 kg stabilizer, 0.15 kg nucleating agent and 1 kg modified graphene oxide prepared in Preparation Example 1;

[0151] S3, heating to 89°C and reacting for 5.5 hours;

[0152] S4, first add 0.25kg dispersant B, then add 0.75kg foaming agent;

[0153] S5, heating to 124°C, reacting for 3.5 hours;

[0154] S6, cooling and discharging the material to obtain environmentally friendly flame retardant expandable polystyrene.

[0155] In this embodiment, dispersant A is active calcium phosphate; reagent A is carboxymethyl cellulose; reagent B is potassium persulfate; initiator A is benzoyl peroxide; initiator B is diisopropylbenzene peroxide; initiator C is tert-butyl peroxycarbonate-2-ethylhexyl ester; the flame retardant is brominated styrene butadiene copolymer; the plasticizer is epoxy resin; the stabilizer is a mixture of magnesium phosphate and zinc phosphate in a weight ratio of 1:1; the nucleating agent is polyethylene wax; the dispersant B is a mixture of calcium phosphate and calcium carbonate in a weight ratio of 1:1; and the foaming agent is n-pentane.

[0156] Application Examples

[0157] Application Example 1

[0158] This application example discloses a method for preparing an environmentally friendly flame-retardant expandable polystyrene sheet, comprising the following steps:

[0159] S1. Pre-expand the environmentally friendly flame-retardant expandable polystyrene prepared in Example 1, wherein the pre-expanding steam temperature is 100° C. and the steam pressure is 0.1 MPa;

[0160] S2, then the pre-fermented raw materials are ripened for 24 hours;

[0161] S3. Finally, the matured raw materials are placed in a plate forming machine for forming. The internal pressure of the plate forming machine is 0.06MPa, and the plate forming steam pressure is 0.7MPa. The apparent density is 22kg / m 3 of the board.

[0162] Application Example 2

[0163] This application example discloses a method for preparing an environmentally friendly flame-retardant expandable polystyrene sheet, comprising the following steps:

[0164] S1. Pre-expand the environmentally friendly flame-retardant expandable polystyrene prepared in Example 2, with the pre-expanding steam temperature being 100° C. and the steam pressure being 0.1 MPa;

[0165] S2, then the pre-fermented raw materials are ripened for 24 hours;

[0166] S3. Finally, the matured raw materials are placed in a plate forming machine for forming. The internal pressure of the plate forming machine is 0.06MPa, and the plate forming steam pressure is 0.7MPa. The apparent density is 22kg / m 3 of the board.

[0167] Application Example 3

[0168] This application example discloses a method for preparing an environmentally friendly flame-retardant expandable polystyrene sheet, comprising the following steps:

[0169] S1. Pre-expand the environmentally friendly flame-retardant expandable polystyrene prepared in Example 3, wherein the pre-expanding steam temperature is 100° C. and the steam pressure is 0.1 MPa;

[0170] S2, then the pre-fermented raw materials are ripened for 24 hours;

[0171] S3. Finally, the matured raw materials are placed in a plate forming machine for forming. The internal pressure of the plate forming machine is 0.06MPa, and the plate forming steam pressure is 0.7MPa. The apparent density is 22kg / m 3 of the board.

[0172] Application Example 4

[0173] This application example discloses a method for preparing an environmentally friendly flame-retardant expandable polystyrene sheet, comprising the following steps:

[0174] S1. Pre-expand the environmentally friendly flame-retardant expandable polystyrene prepared in Example 4, wherein the pre-expanding steam temperature is 100° C. and the steam pressure is 0.1 MPa;

[0175] S2, then the pre-fermented raw materials are ripened for 24 hours;

[0176] S3. Finally, the matured raw materials are placed in a plate forming machine for forming. The internal pressure of the plate forming machine is 0.06MPa, and the plate forming steam pressure is 0.7MPa. The apparent density is 22kg / m 3 of the board.

[0177] Application Example 5

[0178] This application example discloses a method for preparing an environmentally friendly flame-retardant expandable polystyrene sheet, comprising the following steps:

[0179] S1. Pre-expand the environmentally friendly flame-retardant expandable polystyrene obtained in Example 5, wherein the pre-expanding steam temperature is 100° C. and the steam pressure is 0.1 MPa;

[0180] S2, then the pre-fermented raw materials are ripened for 24 hours;

[0181] S3. Finally, the matured raw materials are placed in a plate forming machine for forming. The internal pressure of the plate forming machine is 0.06MPa, and the plate forming steam pressure is 0.7MPa. The apparent density is 22kg / m 3 of the board.

[0182] Application Example 6

[0183] This application example discloses a method for preparing an environmentally friendly flame-retardant expandable polystyrene sheet, comprising the following steps:

[0184] S1. Pre-expand the environmentally friendly flame-retardant expandable polystyrene prepared in Example 6, wherein the pre-expanding steam temperature is 100° C. and the steam pressure is 0.1 MPa;

[0185] S2, then the pre-fermented raw materials are ripened for 24 hours;

[0186] S3. Finally, the matured raw materials are placed in a plate forming machine for forming. The internal pressure of the plate forming machine is 0.06MPa, and the plate forming steam pressure is 0.7MPa. The apparent density is 22kg / m 3 of the board.

[0187] Application Example 7

[0188] This application example discloses a method for preparing an environmentally friendly flame-retardant expandable polystyrene sheet, comprising the following steps:

[0189] S1. Pre-expand the environmentally friendly flame-retardant expandable polystyrene obtained in Example 7, wherein the pre-expanding steam temperature is 100° C. and the steam pressure is 0.1 MPa;

[0190] S2, then the pre-fermented raw materials are ripened for 24 hours;

[0191] S3. Finally, the matured raw materials are placed in a plate forming machine for forming. The internal pressure of the plate forming machine is 0.06MPa, and the plate forming steam pressure is 0.7MPa. The apparent density is 22kg / m 3 of the board.

[0192] Application Example 8

[0193] This application example discloses a method for preparing an environmentally friendly flame-retardant expandable polystyrene sheet, comprising the following steps:

[0194] S1. Pre-expand the environmentally friendly flame-retardant expandable polystyrene prepared in Example 8, wherein the pre-expanding steam temperature is 100° C. and the steam pressure is 0.1 MPa;

[0195] S2, then the pre-fermented raw materials are ripened for 24 hours;

[0196] S3. Finally, the matured raw materials are placed in a plate forming machine for forming. The internal pressure of the plate forming machine is 0.06MPa, and the plate forming steam pressure is 0.7MPa. The apparent density is 22kg / m 3 of the board.

[0197] Application Example 9

[0198] This application example discloses a method for preparing an environmentally friendly flame-retardant expandable polystyrene sheet, comprising the following steps:

[0199] S1. Pre-expand the environmentally friendly flame-retardant expandable polystyrene prepared in Example 9, wherein the pre-expanding steam temperature is 100° C. and the steam pressure is 0.1 MPa;

[0200] S2, then the pre-fermented raw materials are ripened for 24 hours;

[0201] S3. Finally, the matured raw materials are placed in a plate forming machine for forming. The internal pressure of the plate forming machine is 0.06MPa, and the plate forming steam pressure is 0.7MPa. The apparent density is 22kg / m 3 of the board.

[0202] Application Example 10

[0203] This application example discloses a method for preparing an environmentally friendly flame-retardant expandable polystyrene sheet, comprising the following steps:

[0204] S1. Pre-expand the environmentally friendly flame-retardant expandable polystyrene obtained in Example 10, wherein the pre-expanding steam temperature is 100° C. and the steam pressure is 0.1 MPa;

[0205] S2, then the pre-fermented raw materials are ripened for 24 hours;

[0206] S3. Finally, the matured raw materials are placed in a plate forming machine for forming. The internal pressure of the plate forming machine is 0.06MPa, and the plate forming steam pressure is 0.7MPa. The apparent density is 22kg / m 3 of the board.

[0207] Performance testing

[0208] Thermal conductivity (thermal conductivity GB / T10294), flame retardancy (flame retardancy grade GB8624-2012), tensile strength (JG149-2003), compression performance (GB / T8813), dimensional stability (GB / T 6342 dimensional deviation), breaking bending load capacity (GB / T8812)

[0209] The performance tests were carried out on the boards made from Examples 1-10. The test items and reference standards are as follows:

[0210] 1. Thermal conductivity, GB / T 10294-2008 "Determination of steady-state thermal resistance and related properties of insulation materials - Guarded hot plate method";

[0211] 2. Flame retardant grade, GB 8624-2012 "Classification of Combustion Performance of Building Materials and Products";

[0212] 3. Tensile strength, JG149-2003 "Expanded polystyrene board thin plaster exterior wall insulation system";

[0213] 4. Compression strength, GB / T 8813-2020 "Determination of compression properties of rigid foam plastics";

[0214] 5. Dimensional deviation, GB / T 6342-1996 "Determination of linear dimensions of foam plastics and rubber";

[0215] 6. Breaking bending load, GB / T 8812-1988 "Bending test method for rigid cellular plastics".

[0216] Table 1 Application Example 1-12 Performance Test Data Table

[0217]

[0218]

[0219] Combining Application Example 2 and Application Example 5 with Table 1, it can be seen that the performance of the board can be effectively improved by adding the enhanced modified composite powder. Based on the solution of Application Example 2, the addition of the flame retardant causes the performance of the prepared polystyrene to decrease due to poor compatibility, while the enhanced modified composite powder compensates for the decrease in the performance of the polystyrene caused by the addition of the flame retardant.

[0220] It can be seen from Application Examples 4, 5 and 6 and Table 1 that by adjusting the amount of the enhanced modified composite powder added, the properties of the polystyrene finally obtained are changed, and by selecting the most appropriate ratio, the properties of the polystyrene can be effectively enhanced.

[0221] It can be seen from Application Examples 4, 7 and 8 and Table 1 that by selecting graphene oxide, unsaturated fatty acids and conjugated dienes, graphene oxide is first combined with unsaturated fatty acids to perform chlorination reaction, thereby improving the compatibility of modified graphene oxide in oily auxiliary materials, making it easier to disperse modified graphene oxide in oily auxiliary materials, and then forming graphene oxide containing cyclic unsaturated fatty acids through the unsaturated fatty acids on the graphene oxide and the conjugated dienes, thereby improving the dispersion performance of graphene oxide and the overall stability of the modified graphene oxide, thereby being more conducive to the dispersion of graphene oxide.

[0222] It can be seen from Application Examples 4, 9 and 10 and Table 1 that the double modification of graphene oxide makes the double-modified graphene oxide evenly dispersed, which is more conducive to improving the performance of the board.

[0223] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed. However, as long as it is within the scope of the claims of the present application, it shall be protected by the patent law.

Claims

1. A method for preparing environmentally friendly flame retardant expandable polystyrene, characterized in that: The following steps are involved: S1, add 110 parts by weight of pure water into the reactor; Add the following aqueous auxiliary materials and stir evenly: 0.06-0.08 parts by weight of dispersant A, 0.0014-0.0018 parts by weight of reagent A, 0.001-0.0012 parts by weight of reagent B; S2, add 100 parts by weight of styrene; add the following oily auxiliary materials and stir evenly: 0.25-0.55 parts by weight of initiator A, 0.03-0.08 parts by weight of initiator B, 0.2-0.5 parts by weight of initiator C, 0.6-0.9 parts by weight of flame retardant, 0.2-0.6 parts by weight of plasticizer, 0.005-0.008 parts by weight of stabilizer and 0.1-0.2 parts by weight of nucleating agent; 0.5 to 1.5 parts by weight of reinforced modified composite powder; S3, heating to 88-90°C and reacting for 5-6 hours; S4, first add 0.2-0.3 parts by weight of dispersant B, and then add 0.5-1.2 parts by weight of foaming agent; S5, heating to 118-130°C, reacting for 2.5-5 hours; S6, cooling and discharging; The dispersant A is active calcium phosphate; The reagent A is one or more of polyvinyl alcohol, carboxymethyl cellulose and carboxyethyl cellulose; The reagent B is potassium persulfate; The dispersant B is a mixture of calcium phosphate and calcium carbonate in a ratio of 1:1 by weight; The enhanced modified composite powder is prepared by the following steps: mixing calcium metaborate with oleic acid mixed with polyethylene glycol monomethyl ether and ball milling, then adding modified graphene oxide and continuing to mix and ball mill; The modified graphene oxide is prepared by the following steps: S1), take 0.5g of graphene oxide and dissolve it in 150mL of dehydrated DMF solvent, transfer it to a 250mL four-necked flask equipped with a dry tail pipe and an exhaust gas removal device after uniform dispersion, add 20mL of acrylic acid or linoleic acid, 1mg of hydroquinone inhibitor, 30mg of triethylamine, and then slowly add 30mL of dichlorothionyl, stir magnetically, pass nitrogen protection, react in an ice bath for 2h and then at room temperature overnight; after the reaction is completed, filter to remove a small amount of black insoluble matter, wash the filtrate with water to obtain a brown product deposited at the bottom, let it stand and pour off the supernatant, wash it repeatedly with water, centrifuge it at 10000 rpm for 3 times to remove the small molecular byproducts and a small amount of self-polymerized acrylic acid or linoleic acid wrapped in the product, and freeze-dry at -40℃ to obtain a brown intermediate product; S2), add 2g of the intermediate product prepared in S1), 2g of conjugated butadiene and 25mL of anhydrous xylene into a 50mL round-bottom flask, connect a reflux condenser, and heat to reflux at 140°C for 25min; shake the crystals precipitated on the edge of the liquid surface, continue heating for 5min, stop heating, and filter while hot through a preheated Buchner funnel when there is no reflux, cool the filtrate, separate the solid product by suction, and dry it in a vacuum dryer to obtain modified graphene oxide.

2. The method for preparing environmentally friendly flame retardant expandable polystyrene according to claim 1, characterized in that: The foaming agent is one or more of n-pentane, isopentane and neopentane.

3. The method for preparing environmentally friendly flame retardant expandable polystyrene according to claim 1, characterized in that: The initiator A is one or more of azobisisobutyronitrile, benzoyl peroxide and tert-butyl peroxy-2-ethylhexyl carbonate; The initiator B is one or two of dicumyl peroxide and bis(4-tert-butylcyclohexyl) peroxydicarbonate; The initiator C is one or both of tert-butyl perbenzoate and tert-butyl peroxyneodecanoate.

4. The method for preparing environmentally friendly flame retardant expandable polystyrene according to claim 1, characterized in that: The expandable polystyrene is used to prepare a foam board, and the preparation steps are: the environmentally friendly flame-retardant expandable polystyrene is subjected to pre-expansion, aging and molding processes to prepare the foam board.

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