A flame retardant polyester diol and a flame retardant waterborne polyurethane

Abstract

The invention discloses a flame-retardant polyester diol and a flame-retardant waterborne polyurethane. The flame-retardant polyester diol is prepared by the following steps: (1) mixing phosphate ester and phosphorus-containing oxide, adding polyol and catalyst I to react to obtain oligomeric phosphate ester; (2) adding dibasic acid I to the oligomeric phosphate for reaction, adding dibasic acid II and catalyst II to react, vacuuming to remove moisture, cooling to below 80°C when the acid value is less than 2mgKOH / g, and filtering to obtain the flame-retardant polyester diol. The invention uses phosphate ester and phosphorus-containing oxide to increase the phosphorus content in the polyester diol, thereby improving the flame retardant performance, and adding polyol and compound dibasic acid to react under the action of a catalyst to generate the flame-retardant polyester diol, which not only increases the molecular weight of the polyol, but also reduces the acid value of the system. The low acid value makes the flame-retardant diol as a raw material easier to react with isocyanate in the process of preparing polyurethane, thereby generating polyurethane with better flame retardant performance.

Description

Technical Field

[0001] The invention relates to the technical field of flame-retardant polymers, in particular to a flame-retardant polyester diol and a flame-retardant waterborne polyurethane. Background Art

[0002] As a special daily necessity, leather products are increasingly used in a wide range of applications, and are gradually expanding to high-end consumer areas, such as interior decoration, office, and transportation. As the scope of application becomes wider and wider, and the relationship with daily life becomes increasingly close, this requires specifications to have certain flame retardancy to meet the requirements of safety and fire protection. At present, many countries in the world have strict requirements on the flame retardancy of leather goods used in flight crew clothing and aviation equipment. With the improvement of people's living standards in my country, flame retardant finishing agents are increasingly valued.

[0003] At present, flame retardant finishing agents for synthetic leather are mainly flame retardant polyurethanes, and the raw materials for the production of flame retardant polyurethanes are mainly halogen-containing and phosphorus-containing polyether polyols. However, halogen-containing polyether polyols will produce a large amount of toxic gases in the early stage of combustion, which will cause secondary harm to personnel safety and do not meet the relevant regulations on interior decoration. Phosphorus-containing polyether polyols contain PO bonds, which have poor hydrolysis stability and are easy to neutralize part of the tertiary amine catalyst during use, resulting in reduced catalytic activity and poor heat resistance, thereby reducing its flame retardant properties. In addition, phosphorus-containing polyether polyols are expensive and have poor compatibility, which limits their actual use. Summary of the invention

[0004] The technical problem to be solved by the present invention is that the phosphorus content of the current flame retardant polyurethane is not high and the stability is poor.

[0005] To this end, according to a first aspect, the present invention provides a flame retardant polyester diol, and the flame retardant polyester diol is prepared by the following steps:

[0006] (1) After mixing the phosphate ester and the phosphorus-containing oxide, the mixture is kept warm for reaction at 130° C.-180° C. and 0.03-0.08 MPa for 40-50 minutes; polyol and catalyst I are added, and the mixture is kept warm for reaction at 130-180° C. for 3-4 hours to obtain the oligomeric phosphate ester;

[0007] (2) Adding dibasic acid I to the oligomeric phosphate obtained in step (1) in 2-3 portions, raising the temperature to 130-180° C. and reacting at a constant temperature for 2-3 hours, adding dibasic acid II and catalyst II and raising the temperature to 180-230° C. and reacting at a constant temperature for 2-3 hours, vacuuming to remove moisture at -0.06 to -0.1 MPa, taking samples to measure the acid value, and cooling when the acid value is less than 2 mgKOH / g. When the temperature drops to below 80° C., filtering to obtain a flame-retardant polyester diol.

[0008] Further, the phosphate ester is one or more of trimethyl phosphate, tetraphenyltoluene diphenol diphosphate, and tetraphenyl (bisphenol A) diphosphate (BDP);

[0009] And / or, the phosphorus-containing oxide is one of phosphorus trioxide and phosphoric anhydride;

[0010] And / or, the polyol is one of sorbitol and pentaerythritol;

[0011] and / or, the catalyst I is one of organic bismuth, stannous octoate, and dibutyltin dilaurate;

[0012] and / or, the dibasic acid I is one or more of adipic acid, succinic acid, and 1,4-cyclohexanedicarboxylic acid;

[0013] and / or, the dibasic acid II is one or more of isophthalic acid, phthalic anhydride, and sulfonate isophthalic acid;

[0014] And / or, catalyst II is one or more of antimony acetate, antimony trioxide, antimony glycol, and organic bismuth.

[0015] Furthermore, the amount of phosphorus-containing oxide accounts for 10-20% of the total amount of flame-retardant polyester diol raw materials, the amount of phosphate accounts for 40-60% of the total amount of flame-retardant polyester diol raw materials, the amount of polyol accounts for 10-30% of the total amount of flame-retardant polyester diol raw materials, the amount of catalyst I accounts for 0.3-0.8% of the total amount of flame-retardant polyester diol raw materials, the amount of dibasic acid I accounts for 10-20% of the total amount of flame-retardant polyester diol raw materials, the amount of dibasic acid II accounts for 5-15% of the total amount of flame-retardant polyester diol raw materials, and the amount of catalyst II accounts for 0.2-0.5% of the total amount of flame-retardant polyester diol raw materials.

[0016] Furthermore, the total amount of the flame-retardant polyester diol raw materials is the sum of the amounts of phosphate, phosphorus-containing oxide, polyol, catalyst I, dibasic acid I, dibasic acid and catalyst II.

[0017] In a second aspect, the present invention provides a flame retardant waterborne polyurethane, which is prepared using the flame retardant polyester diol provided in the first aspect as a raw material.

[0018] Further, the flame retardant waterborne polyurethane is prepared by the following steps:

[0019] (1) Mixing oligomer diol, polyhydric alcohol and flame-retardant polyester diol, heating to 60-65° C., adding diisocyanate and acetone after the polyhydric alcohol is completely dissolved, and continuing to heat to 90-100° C. for reaction for 3-4 hours, taking samples to test the -NCO content to the theoretical value to obtain a prepolymer;

[0020] (2) mixing the prepolymer prepared in step (1) with a diol chain extender, a hydroxyl-containing long-chain hydrocarbon, a catalyst and acetone, heating the mixture to 70-80° C. and reacting the mixture for 2-3 hours, taking a sample and measuring the -NCO content until the theoretical value is reached to obtain a polymer;

[0021] (3) cooling to 40-55° C., mixing the polymer prepared in step (2) with the aminocarboxylate, and keeping the temperature for reaction for 15-25 min; cooling to 40-45° C., slowly adding the aminosulfonate, heating to 50-55° C. after the addition is complete, keeping the temperature for reaction for 20-40 min, cooling to below 30° C., transferring to a dispersion kettle, setting the dispersion speed at 2000 rpm, and injecting metered deionized water so that the solid content is 40%-45%;

[0022] Set the dispersion speed to 800-1000rpm, slowly drop an active hydrogen amine chain extender with a dilution ratio of 5-20%, stir to react for 20-40min, let stand and mature for more than 10h, remove acetone and filter to obtain flame-retardant waterborne polyurethane.

[0023] Furthermore, in step (1), the amount of oligomer diol accounts for 30-50% of the total amount of prepolymer raw materials, the amount of polyhydric alcohol accounts for 1-3% of the total amount of prepolymer raw materials, the amount of flame retardant polyester diol accounts for 10-30% of the total amount of prepolymer raw materials, the amount of diisocyanate accounts for 20-40% of the total amount of prepolymer raw materials, and the amount of acetone accounts for 3% of the total amount of prepolymer raw materials.

[0024] Furthermore, in step (1), the total amount of prepolymer raw materials is the sum of the amounts of oligomer diol, polyhydric alcohol, flame-retardant polyester diol, diisocyanate and acetone.

[0025] Furthermore, in step (2), the amount of diol chain extender accounts for 1-3% of the total amount of polymer raw material, the amount of hydroxyl-containing long-chain hydrocarbon accounts for 2-5% of the total amount of polymer raw material, and the amount of catalyst accounts for 0.2-0.5% of the total amount of polymer raw material.

[0026] Furthermore, in step (2), the total amount of polymer raw materials is the sum of the amounts of prepolymer, diol chain extender, hydroxyl-containing long-chain hydrocarbon and catalyst used in step (1).

[0027] Furthermore, in step (3), the amount of aminocarboxylate accounts for 0.3-1% of the total amount of the flame-retardant waterborne polyurethane raw material, the amount of diamine sulfonate accounts for 2-8% of the total amount of the flame-retardant waterborne polyurethane raw material, and the amount of active hydrogen amine chain extender accounts for 1-3% of the total amount of the flame-retardant waterborne polyurethane raw material;

[0028] Furthermore, in step (3), the total amount of the flame-retardant waterborne polyurethane raw material is the sum of the amounts of the polymer, aminocarboxylate, diamine sulfonate and active hydrogen-containing amine chain extender in step (2).

[0029] Further, the oligomer diol is one or more of PTMG-2000, PCL-2000, and PCDL-2000;

[0030] And / or, the polyhydric alcohol is one or more of glycerol and trimethylolpropane;

[0031] and / or, the diisocyanate is one or more of isophorone diisocyanate, toluene diisocyanate, and dicyclohexylmethane diisocyanate;

[0032] and / or, the diol chain extender is one or more of decanediol, ethyl butyl propanediol, trimethylpentanediol, and trimethylolpropane monoglyceride;

[0033] and / or, the hydroxyl-containing long-chain hydrocarbon is one or more of stearic acid amide, oleic acid amide, and erucic acid amide;

[0034] and / or, the catalyst is one or more of stannous octoate, dibutyltin dilaurate and organic bismuth;

[0035] and / or, the aminocarboxylate is one or more of sodium diaminocarboxylate (CE-95) and sodium N-(2-aminoethyl)-aminopropionate;

[0036] and / or, the aminosulfonate is one or more of 2-[(2-aminoethyl)amino]ethanesulfonic acid sodium salt and 2-(2-aminoethylamino)propanesulfonic acid sodium salt;

[0037] And / or, the active hydrogen-containing amine chain extender is one or more of 1,4-cyclohexanedimethylamine, isophoronediamine, and meta-xylylenediamine.

[0038] Further, the theoretical value range of -NCO content in step (1) is 6%-7%;

[0039] And / or, the theoretical value range of -NCO content in step (2) is 3%-4%.

[0040] The technical solution provided by the present invention has the following advantages:

[0041] 1. The flame-retardant polyester diol provided by the present invention uses phosphate ester and phosphorus-containing oxide as raw materials to increase the phosphorus content in the polyester diol, thereby effectively improving the flame retardant performance, and adding polyols and compound dibasic acids to react under the action of a catalyst to generate the flame-retardant polyester diol, which not only increases the molecular weight of the polyol, but also reduces the acid value of the system. The low acid value makes the flame-retardant diol, as a raw material for flame-retardant polyurethane, easier to react with isocyanate during the preparation of polyurethane to generate polyurethane with better flame retardant performance.

[0042] 2. The flame-retardant polyester diol provided by the present invention adopts step-by-step addition of aromatic dibasic acid and fatty dibasic acid to maintain the acid concentration in the reaction, so as to keep the reaction going continuously, thereby avoiding the problems of too low reaction activity and slow reaction caused by the use of a single aromatic dibasic acid, or too high reaction activity and excessive heat release caused by the use of a single fatty dibasic acid.

[0043] 3. The flame-retardant waterborne polyurethane provided by the present invention is prepared using the flame-retardant polyester diol as a raw material, has good flame-retardant properties, uses hydroxyl-containing long-chain hydrocarbons to make the polyurethane have better hydrolysis resistance stability, and uses two amino salt hydrophilic chain extenders to finally obtain a flame-retardant waterborne polyurethane with a low solvent content and a high solid content, which is beneficial to improving the flame-retardant properties. DETAILED DESCRIPTION

[0044] The technical solution of the present invention will be clearly and completely described below in conjunction with specific implementation methods. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] Example 1

[0046] This embodiment provides a flame retardant waterborne polyurethane, and the specific preparation method is as follows:

[0047] S1: Preparation of flame-retardant polyester diols

[0048] (1) Add 90 g of trimethyl phosphate and 25 g of phosphoric anhydride into a four-necked flask equipped with an electric heating mantle, a temperature controller, a stirrer, a spherical condenser and a nitrogen tube, and keep the temperature at 150° C. and 0.05 MPa for 45 min; add 25 g of sorbitol and 0.55 g of organobismuth, and keep the temperature at 150° C. for 4 h to obtain oligomeric phosphate;

[0049] (2) 19.2 g of succinic acid was added to the oligomeric phosphate obtained in step (1) in two portions, and the mixture was kept in a constant temperature at 150° C. for 2.5 h. 12.3 g of isophthalic acid and 0.6 g of antimony glycol were added and the temperature was raised to 200° C. for a constant temperature reaction for 3 h. When the amount of distillate was significantly reduced and increasing the nitrogen flow rate did not significantly increase the amount of distillate, the water was removed by vacuum extraction at -0.08 MPa, and the acid value of the sample was measured. When the acid value was <2 mg KOH / g, the temperature was lowered to below 80° C., and the flame-retardant polyester diol was obtained by filtration.

[0050] S2: Preparation of flame retardant waterborne polyurethane.

[0051] (1) 77.4 g PTMG-2000, 3 g trimethylolpropane, and 40 g flame-retardant polyester diol were placed in a reaction kettle, mixed evenly, and then heated to 63° C. When the trimethylolpropane was completely dissolved, 60 g isophorone diisocyanate and acetone were added, and then heated to 95° C. for reaction for 3.5 h. Samples were taken for testing the -NCO content to 7%, thus obtaining a prepolymer, and the temperature was lowered for the next step;

[0052] (2) The prepolymer prepared in step (1) was mixed with 3.1 g of trimethylpentanediol, 4.3 g of stearic acid amide, 0.6 g of dibutyltin dilaurate and acetone, and the temperature was raised to 78° C. for reaction for 3 h. The -NCO content was measured by sampling and the polymer was obtained when it was 4%. The temperature was lowered to proceed to the next step.

[0053] (3) Cooling to 55° C., mixing the polymer obtained in step (2) with 1.2 g of sodium diaminocarboxylate (CE-95) and incubating for 20 min; cooling to 45° C., slowly dropping 8.5 g of 2-[(2-aminoethyl)amino]ethanesulfonic acid sodium salt, heating to 53° C. and incubating for 30 min after the addition, cooling to below 30° C., transferring to a dispersion kettle, setting the dispersion speed to 2000 rpm, and rapidly injecting metered deionized water so that the solid content of the product is 45%; setting the dispersion speed to 900 rpm, diluting 3 g of isophorone diamine at a dilution ratio of 15%, slowly dropping, stirring for 30 min, standing for aging for more than 10 h, removing acetone by vacuum distillation, and filtering to obtain a flame-retardant waterborne polyurethane.

[0054] Example 2

[0055] This embodiment provides a flame retardant waterborne polyurethane, and the specific preparation method is as follows:

[0056] S1: Preparation of flame-retardant polyester diols

[0057] (1) Add 120 g of tetraphenyltoluene diphenol diphosphate and 20 g of phosphorus trioxide into a four-necked flask equipped with an electric heating mantle, a temperature controller, a stirrer, a spherical condenser and a nitrogen tube, and keep the temperature at 130° C. and 0.08 MPa for 50 min; add 20 g of pentaerythritol and 1.6 g of stannous octoate, and keep the temperature at 130° C. for 4 h to obtain oligomeric phosphate;

[0058] (2) Add 20 g of adipic acid to the oligomeric phosphate obtained in step (1) in three portions, raise the temperature to 180° C. and react at this temperature for 2 h, add 18 g of phthalic anhydride and 0.4 g of antimony acetate and raise the temperature to 200° C. and react for 3 h. When the amount of distillate is significantly reduced and increasing the nitrogen flow rate does not significantly increase the amount of distillate, vacuum remove the water under -0.06 MPa, take a sample and measure the acid value. When the acid value is less than 2 mg KOH / g, cool the sample until the temperature drops to below 80° C. and filter to obtain a flame-retardant polyester diol.

[0059] S2: Preparation of flame-retardant waterborne polyurethane

[0060] (1) 100 g PCL-2000, 1.4 g glycerol, and 20 g flame-retardant polyester diol were placed in a reactor, mixed evenly, and then heated to 60° C. When the glycerol was completely dissolved, 72.6 g toluene diisocyanate and 6 g acetone were added, and then the temperature was raised to 90° C. for reaction for 4 h. The -NCO content of the sample was tested to be 6%, and the prepolymer was obtained. The temperature was lowered to proceed to the next step;

[0061] (2) The prepolymer prepared in step (1) was heated to 80° C. and kept for reaction for 2 h. The -NCO content was measured to obtain a polymer when it reached 3%, and the temperature was lowered to proceed to the next step.

[0062] (3) Cooling to 40°C, mixing the polymer obtained in step (2) with 2.5g of sodium N-(2-aminoethyl)-aminopropionic acid and reacting for 25min; maintaining the temperature at 40°C, slowly dropping 5g of sodium 2-(2-aminoethylamino)propanesulfonate, raising the temperature to 50°C after the addition, and reacting for 40min, cooling to below 30°C, transferring to a dispersion kettle, setting the dispersion speed to 2000rpm, and quickly injecting metered deionized water so that the solid content of the product is 40%; setting the dispersion speed to 1000rpm, diluting 7.5g of 1,4-cyclohexanedimethylamine at a dilution ratio of 5%, slowly dropping, stirring and reacting for 20min, standing and maturing for more than 10h, removing acetone by vacuum distillation, and filtering to obtain a flame-retardant waterborne polyurethane.

[0063] Example 3

[0064] This embodiment provides a flame retardant waterborne polyurethane, and the specific preparation method is as follows:

[0065] S1: Preparation of flame-retardant polyester diols

[0066] (1) Add 80 g of tetraphenyl (bisphenol A) diphosphate (BDP) and 40 g of phosphoric anhydride into a four-necked flask equipped with an electric heating jacket, a temperature controller, a stirrer, a spherical condenser and a nitrogen tube, and keep the temperature at 180° C. and 0.03 MPa for 40 min; add 28.4 g of sorbitol and 0.6 g of dibutyltin dilaurate, and keep the temperature at 180° C. for 3 h to obtain oligomeric phosphate;

[0067] (2) Add 40 g of 1,4-cyclohexanedicarboxylic acid to the oligomeric phosphate obtained in step (1) in two portions, react at 180° C. for 2 h, add 10 g of sulfonated isophthalic acid and 1 g of antimony trioxide, heat to 230° C. for 2 h, and remove moisture by vacuuming at -0.1 MPa. Take a sample to measure its acid value. When the acid value is less than 2 mg KOH / g, cool the sample until the temperature drops to below 80° C., filter the sample to obtain a flame-retardant polyester diol.

[0068] S2: Preparation of flame-retardant waterborne polyurethane

[0069] (1) 60 g PCDL-2000, 4 g trimethylolpropane, and 50 g flame-retardant polyester diol were put into a reactor, mixed evenly, and then heated to 65° C. When the trimethylolpropane was completely dissolved, 80 g dicyclohexylmethane diisocyanate and 6 g acetone were added, and then heated to 90° C. for 4 h. The -NCO content of the sample was tested to be 6.5%, and the prepolymer was obtained. The temperature was lowered to proceed to the next step;

[0070] (2) The prepolymer prepared in step (1) was heated to 70° C. for 3 h with 2.2 g of ethyl butyl propanediol, 11 g of erucic acid amide, 0.44 g of organic bismuth and 6.6 g of acetone. The -NCO content was measured by sampling and the polymer was obtained when it was 3.5%. The temperature was lowered to proceed to the next step.

[0071] (3) Cooling to 50° C., mixing the polymer obtained in step (2) with 0.75 g of sodium diaminocarboxylate (CE-95) and incubating for 15 min; maintaining the temperature at 43° C., slowly dropping 20 g of 2-[(2-aminoethyl)amino]ethanesulfonic acid sodium salt and 2-(2-aminoethylamino)propanesulfonic acid sodium salt, heating to 55° C. and incubating for 20 min after the addition is complete, cooling to below 30° C., transferring to a dispersion kettle, setting the dispersion speed to 2000 rpm, and rapidly injecting metered deionized water so that the product solid content is 42%; setting the dispersion speed to 800 rpm, diluting 7.5 g of m-phenylenediamine at a dilution ratio of 20%, slowly dropping, stirring for 40 min, standing for aging for more than 10 h, removing acetone by vacuum distillation, and filtering to obtain a flame-retardant waterborne polyurethane.

[0072] Example 4

[0073] This embodiment provides a flame retardant waterborne polyurethane, and the specific preparation method is as follows:

[0074] S1: Preparation of flame-retardant polyester diols

[0075] (1) Add 50 g of trimethyl phosphate, 50 g of tetraphenyltoluene diphenol diphosphate and 30 g of phosphorus trioxide into a four-necked flask equipped with an electric heating mantle, a temperature controller, a stirrer, a spherical condenser and a nitrogen tube, and keep the temperature at 160° C. and 0.04 MPa for 45 min; add 60 g of pentaerythritol and 1 g of organic bismuth, and keep the temperature at 160° C. for 3.5 h to obtain oligomeric phosphate;

[0076] (2) Add 10 g of adipic acid and 20 g of succinic acid to the oligomeric phosphate obtained in step (1) in two portions, react at 160° C. for 3 h, add 20 g of isophthalic acid, 10 g of phthalic anhydride and 0.8 g of organic bismuth, raise the temperature to 220° C. for 2 h, and remove moisture by vacuuming at -0.09 MPa, take a sample to measure the acid value, and cool when the acid value is less than 2 mg KOH / g. When the temperature drops to below 80° C., filter to obtain a flame-retardant polyester diol.

[0077] S2: Preparation of flame-retardant waterborne polyurethane

[0078] (1) 36.2 g PTMG-2000, 43.8 g PCL-2000, 1 g glycerol, 1 g trimethylolpropane, and 60 g flame-retardant polyester diol were put into a reactor, mixed evenly, and then heated to 61° C. When glycerol and trimethylolpropane were completely dissolved, 40 g isophorone diisocyanate, toluene diisocyanate, and 5.5 g acetone were added, and then heated to 98° C. for reaction for 3 h. Samples were taken for testing -NCO content to obtain a prepolymer of 6%, and the temperature was lowered to proceed to the next step;

[0079] (2) The prepolymer prepared in step (1) is mixed with 4.4 g trimethylolpropane monoglyceride, 4.3 g stearic acid amide, 3.7 g oleic acid amide, 0.4 g stannous octoate, 0.4 g dibutyltin dilaurate and 5.9 g acetone, and the temperature is raised to 72° C. for reaction for 3 h. The -NCO content of the prepolymer is measured to be 4% to obtain a polymer, and the temperature is lowered to proceed to the next step.

[0080] (3) Cooling to 48° C., mixing the polymer obtained in step (2) with 1.5 g of sodium diaminocarboxylate (CE-95) and 0.5 g of sodium N-(2-aminoethyl)-aminopropionic acid, and incubating for 22 min; Cooling to 42° C., slowly dropping 15 g of sodium 2-(2-aminoethylamino)propanesulfonate, heating to 55° C. and incubating for 20 min after the addition is complete, cooling to below 30° C., transferring to a dispersion kettle, setting the dispersion speed to 2000 rpm, and rapidly injecting metered deionized water so that the solid content of the product is 45%; setting the dispersion speed to 800 rpm, diluting 2.5 g of 1,4-cyclohexanedimethylamine and 2.5 g of isophorone diamine at a dilution ratio of 10%, slowly dropping, stirring for 35 min, standing for aging for more than 10 h, removing acetone by vacuum distillation, and filtering to obtain a flame-retardant waterborne polyurethane.

[0081] Example 5

[0082] This embodiment provides a flame retardant waterborne polyurethane, and the specific preparation method is as follows:

[0083] S1: Preparation of flame-retardant polyester diols

[0084] (1) Add 110 g of tetraphenyl (bisphenol A) diphosphate (BDP) and 35 g of phosphoric anhydride to a four-necked flask equipped with an electric heating mantle, a temperature controller, a stirrer, a spherical condenser and a nitrogen tube, and keep the temperature at 170° C. and 0.07 MPa for 40 min; add 40 g of sorbitol and 1.4 g of dibutyltin dilaurate, and keep the temperature at 170° C. for 3 h to obtain oligomeric phosphate;

[0085] (2) Add 25 g of 1,4-cyclohexanedicarboxylic acid to the oligomeric phosphate obtained in step (1) in three portions, react at 170° C. for 2 h, add 12.3 g of phthalic anhydride, 12.7 g of sulfonated isophthalic acid and 0.5 g of ethylene glycol antimony and organic bismuth, and heat to 190° C. for 3 h. When the amount of distillate is significantly reduced and increasing the nitrogen flow rate does not significantly increase the amount of distillate, remove moisture by vacuuming at -0.09 MPa, take a sample to measure the acid value, and when the acid value is less than 2 mg KOH / g, cool the sample until the temperature drops to below 80° C., filter the sample to obtain a flame-retardant polyester diol.

[0086] S2: Preparation of flame-retardant waterborne polyurethane

[0087] (1) 94.5 g PTMG-2000, 3.6 g glycerol, and 55 g flame-retardant polyester diol were placed in a reaction kettle, mixed evenly, and then heated to 64° C. When the glycerol was completely dissolved, 52.7 g isophorone diisocyanate and 6.2 g acetone were added, and then heated to 97° C. for reaction for 3 h. Samples were taken for testing the -NCO content to 7%, thus obtaining a prepolymer, and the temperature was lowered for the next step;

[0088] (2) The prepolymer prepared in step (1) was heated to 80° C. for 2 h with 2.6 g of ethyl butyl propanediol, 2.5 g of trimethylpentanediol, 8.6 g of erucamide, 0.75 g of dibutyltin dilaurate and 6.6 g of acetone. The mixture was sampled and the -NCO content was measured to be 3% to obtain a polymer. The temperature was then lowered to proceed to the next step.

[0089] (3) Cooling to 50° C., mixing the polymer obtained in step (2) with 2 g of sodium diaminocarboxylate (CE-95) and keeping the mixture warm for 20 min; cooling to 45° C., slowly dropping 12.5 g of sodium 2-[(2-aminoethyl)amino]ethanesulfonic acid; after the addition, heating to 55° C. and keeping the mixture warm for 25 min; cooling to below 30° C., transferring the mixture to a dispersion kettle and setting the dispersion speed to 2000 rpm; rapidly injecting metered deionized water so that the solid content of the product is 44%; setting the dispersion speed to 1000 rpm, diluting 6.4 g of m-phenylenediamine at a dilution ratio of 15%, slowly dropping the mixture, stirring the mixture for 35 min, allowing it to stand for aging for more than 10 h, removing acetone by vacuum distillation, and filtering to obtain a flame-retardant waterborne polyurethane.

[0090] Comparative Example

[0091] This comparative example provides a flame retardant waterborne polyurethane, and the specific preparation method is as follows:

[0092] S1: Preparation of polyester diols

[0093] (1) Add 115 g of hydroxyethylphenylphosphite, 25 g of sorbitol and 0.55 g of organobismuth into a four-necked flask equipped with an electric heating mantle, a temperature controller, a stirrer, a spherical condenser and a nitrogen tube, and keep the reaction at 150° C. for 4 h;

[0094] (2) 19.2 g of succinic acid was added in two portions, and the mixture was kept in a constant temperature at 150° C. for 2.5 h. 12.3 g of isophthalic acid and 0.6 g of antimony glycol were added, and the temperature was raised to 200° C. for 3 h. When the amount of distillate was significantly reduced and increasing the nitrogen flow rate did not significantly increase the amount of distillate, the water was removed by vacuum pumping at -0.08 MPa, and a sample was taken to measure the acid value. When the acid value was <2 mgKOH / g, the temperature was lowered to below 80° C., and the polyester diol was obtained by filtration.

[0095] S2: Preparation of flame-retardant waterborne polyurethane

[0096] (1) 77.4 g PTMG-2000, 3 g trimethylolpropane, and 40 g polyester diol were added to a reaction kettle, mixed evenly, and then heated to 63° C. When the trimethylolpropane was completely dissolved, 60 g isophorone diisocyanate and acetone were added, and then heated to 95° C. for reaction for 3.5 h. Samples were taken for testing the -NCO content to 7%, thus obtaining a prepolymer, and the temperature was lowered for the next step;

[0097] (2) The prepolymer prepared in step (1) was mixed with 3.1 g of trimethylpentanediol, 4.3 g of stearic acid amide, 0.6 g of dibutyltin dilaurate and acetone, and the temperature was raised to 78° C. for reaction for 3 h. The -NCO content was measured by sampling and the polymer was obtained when it was 4%. The temperature was lowered to proceed to the next step.

[0098] (3) Cooling to 55° C., mixing the polymer obtained in step (2) with 1.2 g of sodium diaminocarboxylate (CE-95) and incubating for 20 min; cooling to 45° C., slowly dropping 8.5 g of 2-[(2-aminoethyl)amino]ethanesulfonic acid sodium salt, heating to 53° C. and incubating for 30 min after the addition, cooling to below 30° C., transferring to a dispersion kettle, setting the dispersion speed to 2000 rpm, and rapidly injecting metered deionized water so that the solid content of the product is 45%; setting the dispersion speed to 900 rpm, diluting 3 g of isophorone diamine at a dilution ratio of 15%, slowly dropping, stirring for 30 min, standing for aging for more than 10 h, removing acetone by vacuum distillation, and filtering to obtain a flame-retardant waterborne polyurethane.

[0099] Experimental example

[0100] The flame retardant waterborne polyurethanes prepared in Examples 1-5 and Comparative Examples were tested for performance. The test results are shown in Table 1.

[0101] Among them, the hydrolysis resistance test method: immersion for 168-504h at 70℃ and 95%RH;

[0102] Heat aging test method: Place at 100±2℃ for 24 hours.

[0103] Table 1 Performance test results

[0104]

[0105] It can be seen from the above table that the flame-retardant waterborne polyurethane prepared in Examples 1 to 5 greatly improves the high temperature resistance, and at the same time has high peel strength, abrasion resistance, hydrolysis resistance and heat aging resistance, and can be widely used in daily necessities such as leather goods and other products with high flame retardant requirements.

[0106] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. However, the obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A flame retardant polyester diol, characterized in that: The flame retardant polyester diol is prepared by the following steps: (1) After mixing phosphate ester and phosphoric anhydride, heat-retaining reaction is carried out at 130°C-180°C and 0.03-0.08Mpa for 40-50 minutes; polyol and catalyst I are added, and heat-retaining reaction is carried out at 130-180°C for 3-4 hours to obtain oligomeric phosphate; (2) Adding dibasic acid I to the oligomeric phosphate obtained in step (1) in 2-3 portions, reacting at a constant temperature of 130-180°C for 2-3 hours, adding dibasic acid II and catalyst II, raising the temperature to 180-230°C and reacting for 2-3 hours, vacuuming to remove moisture at -0.06 to -0.1 MPa, taking samples to measure the acid value, and cooling when the acid value is less than 2 mgKOH / g. When the temperature drops to below 80°C, filtering to obtain the flame-retardant polyester diol; The dibasic acid I is one or more of adipic acid, succinic acid, and 1,4-cyclohexanedicarboxylic acid; The dibasic acid II is one or more of isophthalic acid, phthalic anhydride, and sulfonate isophthalic acid.

2. The flame-retardant polyester diol according to claim 1, characterized in that: The phosphate ester is one or more of trimethyl phosphate, tetraphenyltoluene diphenol diphosphate, and tetraphenyl (bisphenol A) diphosphate (BDP); And / or, the polyol is one of sorbitol and pentaerythritol; And / or, the catalyst I is one of organic bismuth, stannous octoate, and dibutyltin dilaurate; And / or, the catalyst II is one or more of antimony acetate, antimony trioxide, antimony glycol, and organic bismuth.

3. The flame-retardant polyester diol according to claim 1, characterized in that: The amount of phosphoric anhydride accounts for 10-20% of the total amount of the flame-retardant polyester diol raw materials, the amount of the phosphate ester accounts for 40-60% of the total amount of the flame-retardant polyester diol raw materials, the amount of the polyol accounts for 10-30% of the total amount of the flame-retardant polyester diol raw materials, the amount of the catalyst I accounts for 0.3-0.8% of the total amount of the flame-retardant polyester diol raw materials, the amount of the dibasic acid I accounts for 10-20% of the total amount of the flame-retardant polyester diol raw materials, the amount of the dibasic acid II accounts for 5-15% of the total amount of the flame-retardant polyester diol raw materials, and the amount of the catalyst II accounts for 0.2-0.5% of the total amount of the flame-retardant polyester diol raw materials.

4. A flame retardant waterborne polyurethane, characterized in that: The flame-retardant waterborne polyurethane is prepared using the flame-retardant polyester diol described in any one of claims 1 to 3 as a raw material.

5. The flame-retardant waterborne polyurethane according to claim 4, characterized in that: The flame retardant waterborne polyurethane is prepared by the following steps: (1) Mix the oligomer diol, polyhydric alcohol and flame-retardant polyester diol and heat them to 60-65°C. When the polyhydric alcohol is completely dissolved, add diisocyanate and acetone. Continue to heat to 90-100°C and react for 3-4 hours. Take a sample and test the -NCO content to the theoretical value to obtain the prepolymer. (2) The prepolymer prepared in step (1) is mixed with a diol chain extender, a catalyst, acetone and a hydroxyl-containing long-chain hydrocarbon, and the mixture is heated to 70-80° C. and kept for reaction for 2-3 hours. The -NCO content is measured by sampling and the theoretical value is obtained to obtain a polymer; (3) Cooling to 40-55°C, mixing the polymer prepared in step (2) with the aminocarboxylate, and reacting at this temperature for 15-25 minutes; maintaining the temperature at 40-45°C, slowly dropping the aminosulfonate, raising the temperature to 50-55°C after the addition, and reacting at this temperature for 20-40 minutes, cooling to below 30°C, transferring to a dispersion kettle, setting the dispersion speed to 2000 rpm, injecting metered deionized water so that the solid content is 40%-45%; setting the dispersion speed to 800-1000 rpm, slowly dropping an active hydrogen amine chain extender with a dilution ratio of 5-20%, stirring for reaction for 20-40 minutes, standing for aging for more than 10 hours, removing acetone, and filtering to obtain a flame-retardant waterborne polyurethane; The hydroxyl-containing long-chain hydrocarbon is one or more of stearic acid amide, oleic acid amide and erucic acid amide.

6. The flame-retardant waterborne polyurethane according to claim 5, characterized in that: In the step (1), the amount of the oligomer diol accounts for 30-50% of the total amount of the prepolymer raw materials, the amount of the polyhydric alcohol accounts for 0.7-2% of the total amount of the prepolymer raw materials, the amount of the flame-retardant polyester diol accounts for 10-30% of the total amount of the prepolymer raw materials, the amount of the diisocyanate accounts for 20-40% of the total amount of the prepolymer raw materials, and the amount of acetone accounts for 3% of the total amount of the prepolymer raw materials.

7. The flame-retardant waterborne polyurethane according to claim 5, characterized in that: In the step (2), the amount of the diol chain extender accounts for 1-3% of the total amount of the polymer raw material, the amount of the hydroxyl-containing long-chain hydrocarbon accounts for 1-5% of the total amount of the polymer raw material, the amount of the catalyst accounts for 0.2-0.5% of the total amount of the polymer raw material, and the amount of acetone accounts for 3% of the total amount of the polymer raw material.

8. The flame-retardant waterborne polyurethane according to claim 5, characterized in that: In the step (3), the amount of the aminocarboxylate accounts for 0.2-1% of the total amount of the flame-retardant waterborne polyurethane raw material, the amount of the aminosulfonate accounts for 2-8% of the total amount of the flame-retardant waterborne polyurethane raw material, and the amount of the active hydrogen-containing amine chain extender accounts for 1-3% of the total amount of the flame-retardant waterborne polyurethane raw material.

9. The flame-retardant waterborne polyurethane according to claim 5, characterized in that: The oligomer diol is one or more of PTMG-2000, PCL-2000, and PCDL-2000; And / or, the polyhydric alcohol is one or more of glycerol and trimethylolpropane; And / or, the diisocyanate is one or more of isophorone diisocyanate, toluene diisocyanate, and dicyclohexylmethane diisocyanate; And / or, the diol chain extender is one or more of decanediol, ethyl butyl propanediol, trimethyl pentanediol, and trimethylolpropane monoglyceride; And / or, the catalyst is one or more of stannous octoate, dibutyltin dilaurate and organic bismuth; and / or, the aminocarboxylate is one or more of CE-95 and sodium N-(2-aminoethyl)-aminopropionate; and / or, the aminosulfonate is one or more of 2-[(2-aminoethyl)amino]ethanesulfonic acid sodium salt and 2-(2-aminoethylamino)propanesulfonic acid sodium salt; And / or, the active hydrogen-containing amine chain extender is one or more of 1,4-cyclohexanedimethylamine, isophoronediamine, and meta-xylylenediamine.

10. The flame-retardant waterborne polyurethane according to claim 5, characterized in that: The theoretical value range of -NCO content in step (1) is 6%-7%; And / or, the theoretical value range of -NCO content in step (2) is 3%-4%.

Images