A polyurethane formulation, a polyurethane and a method for producing the same

Abstract

The present application relates to the field of polyurethane elastomer material, in particular to a polyurethane compound, polyurethane and a preparation method thereof, the polyurethane compound comprises component A and component B; the component A comprises a halogen-substituted polyurethane prepolymer; the component B comprises a modified polyol chain extender and / or a modified polyamine chain extender which are simultaneously substituted by halogen and urethane, the halogen-substituted polyurethane prepolymer is prepared by selecting a composition containing halogen-substituted isocyanate and non-halogen-substituted diisocyanate and polyol, and the modified polyol chain extender and / or the modified polyamine chain extender which are simultaneously substituted by halogen and urethane are used together, so that the obtained polyurethane material has excellent tensile strength, elongation at break and flame retardant performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of polyurethane materials, in particular to a polyurethane composite material, a polyurethane and a preparation method thereof. BACKGROUND

[0002] As a kind of high polymer, polyurethane has many advantages and is widely used in many fields. Its advantages mainly include high efficiency insulation, excellent corrosion resistance, stable quality and high production efficiency, good weather resistance, easy installation and designable structure. This makes polyurethane excellent in building insulation, waterproof and moisture-proof, sound insulation and sound absorption, life furniture, mining and marine engineering. Polyurethane material has high hardness, high toughness and excellent scratch resistance, can withstand high strength friction and pressure, and effectively prolongs the service life. In various working environments such as food processing and chemical production, polyurethane material can resist mechanical damage and chemical erosion and maintain the original structure of the material.

[0003] The composite material for producing polyurethane has strong designability and adjustability. From formula design to molding process, it can be flexibly adjusted according to specific requirements to adapt to the needs of different fields and environments, becoming a high-performance material favored by the material application field. At the same time, as polyurethane composite materials penetrate into more fields, harsh use environments put higher strength requirements on polyurethane composite materials. The inherent flammability of polyurethane is also one of the main problems of using this kind of material. It is very easy to burn in fire environment, producing a large amount of heat, smoke and toxic gas, causing serious damage to the construction and application environment. Therefore, the mechanical properties and flame retardant properties of polyurethane composite materials have attracted more attention from researchers in related fields.

[0004] The general method to improve the flame retardant performance of polyurethane composite material is to physically mix reactive or additive flame retardants. However, research shows that simple physical mixing of flame retardants can affect the mechanical properties of the material. Liquid flame retardants have a significant plasticizing effect on the material itself, increasing the spacing of molecular chains and weakening the hydrogen bonding between molecules, thereby reducing the mechanical properties. After adding solid flame retardants, the hardness of the material increases, while the tensile strength, tear strength and elongation at break all decrease. This is because solid flame retardants have the effect of increasing rigid fillers, thereby increasing the hardness of the system, but at the same time producing stress concentration points, which are more prone to breakage, affecting the strength of the material.

[0005] Therefore, in view of the current problems and development trend of the industry, it is urgent to develop a modification path to simultaneously improve the mechanical properties and flame retardant properties of polyurethane materials. SUMMARY

[0006] Therefore, the present application aims to provide a polyurethane composition, a polyurethane and a preparation method thereof. Two components composed of a halogen-substituted polyurethane prepolymer and a modified polyol chain extender and / or a modified polyamine chain extender substituted by halogen and urethane at the same time are used to introduce halogen as a combustion reaction chain terminator while ensuring the reaction degree, and the crosslinking degree of the modified chain extender is greatly increased compared with the traditional chain extender, thereby realizing the synchronous improvement of the mechanical properties and the flame-retardant properties of the polyurethane material.

[0007] To this end, the present application provides a polyurethane composition, which comprises component A and component B.

[0008] Component A comprises a halogen-substituted polyurethane prepolymer.

[0009] Component B comprises a modified polyol chain extender and / or a modified polyamine chain extender substituted by halogen and urethane at the same time.

[0010] Further, the raw material for preparing the halogen-substituted polyurethane prepolymer comprises a composition containing halogen-substituted isocyanate and non-halogen-substituted diisocyanate and a polyol.

[0011] Preferably, in the composition, the mass content of the halogen-substituted isocyanate is 0.1-35%, more preferably 30-35%.

[0012] Preferably, in the composition, the mass content of the non-halogen-substituted diisocyanate is 65-99.9%, more preferably 65%-70%.

[0013] Preferably, the polyol is selected from one or more of polyoxyethylene polyol, polyoxypropylene polyol, polytetrahydrofuran polyol and tetrahydrofuran-oxidized propylene copolydiol, preferably polytetrahydrofuran polyol, more preferably polytetrahydrofuran polyol with a molecular weight of 400-2000.

[0014] Further, the raw material for preparing the modified polyamine chain extender comprises a composition containing halogen-substituted isocyanate and non-halogen-substituted diisocyanate and a polyamine.

[0015] Preferably, in the composition, the mass content of the halogen-substituted isocyanate is 0.1-20%, more preferably 15-20%.

[0016] Preferably, in the composition, the mass content of the non-halogen-substituted diisocyanate is 80-99.9%, more preferably 80%-85%.

[0017] Preferably, the polyamine is selected from one or more of 3,3'-dichloro-4,4'-diaminodiphenyl methane, 2,4-diamino-3,5-dimethylthiotoluene, melamine, more preferably 2,4-diamino-3,5-dimethylthiotoluene;

[0018] Preferably, the composition and the polyamine are fed in a molar ratio of NCO to NH2 of 1:4-10, more preferably, the composition and the polyamine are fed in a molar ratio of NCO to NH2 of 1:5-6.

[0019] Further, the raw materials for preparing the modified polyol chain extender include a combination of isocyanate substituted with halogen and diisocyanate not substituted with halogen and polyol;

[0020] Preferably, the mass content of isocyanate substituted with halogen in the composition is 0.1-20%, more preferably 15-20%;

[0021] Preferably, the mass content of diisocyanate not substituted with halogen in the composition is 80-99.9%, more preferably 80%-85%;

[0022] Preferably, the polyol is selected from one or more of ethylene glycol, 1,4-butanediol, trimethylolpropane;

[0023] Preferably, the composition and the polyol are fed in a molar ratio of NCO to OH of 1:4-10, more preferably, the composition and the polyol are fed in a molar ratio of NCO to OH of 1:5-6.

[0024] In the present application, the halogen is fluorine, chlorine, bromine or iodine.

[0025] In the present application, the halogen-substituted polyurethane prepolymer, the modified polyol chain extender, and the modified polyamine chain extender are all prepared by conventional polymerization reaction of the respective raw materials.

[0026] In the present application, the combination of isocyanate substituted with halogen and diisocyanate not substituted with halogen is used to prepare the halogen-substituted polyurethane prepolymer with polyol, and the combination of isocyanate substituted with halogen and diisocyanate not substituted with halogen is also used to modify the chain extender components. The halogen structure can decompose into hydrogen halide at the combustion temperature, and the circulation of hydrogen halide can terminate the combustion chain reaction. The residue after the decomposition of hydrogen halide under the combustion condition can promote the dehydration and carbonization of the material, form a carbonized layer with flame retardation, reduce the amount of low molecular weight cracking products, and hinder the normal progress of the combustion reaction. The generated hydrogen halide can also effectively block oxygen and inhibit the combustion reaction. The large amount of halogen structure introduced in the present application significantly improves the flame retardation performance of the polyurethane material.

[0027] The present application experiment found that the traditional small molecule chain extender is modified by a composition containing halogen-substituted isocyanate and unhalogen-substituted diisocyanate, the long-chain structure containing urethane bond in the modified chain extender is interlaced in the polyurethane network in the mixing and curing stage, and the energy can be dispersed in the material when the polyurethane is damaged by the outside world, reducing stress concentration; on the basis of the linking effect provided by the small molecule chain extender, the modified chain extender can also be entangled and stacked between the molecular chains after introducing the main chain, improving the compactness of the structure, significantly improving the crosslinking strength and extensibility of the polyurethane, and improving the tensile strength and toughness of the polyurethane prepared from the composition.

[0028] The present application experiment found that the refined TDI collected from the TDI refining tower can obtain different content compositions containing halogen-substituted isocyanate (or halogen-containing structure isocyanate) and TDI after the process treatment of rectification separation, because the halogen-containing structure isocyanate still retains the -NCO group, and is very similar to the structure of TDI, its reactivity and compatibility in the reaction process with alcohol / amine are better than those of other types of additives, so a higher additive amount can be provided to improve various performances.

[0029] The present application experiment found that the content of TDI and other isocyanates in the first composition can be controlled by controlling the raw material index, multiple rectification purification or separation means in the production process to ensure the activity of the product in the downstream application, which undoubtedly puts forward strict requirements for the refining / separation capacity and operating conditions of the production device, and the application of the halogen-containing structure TDI in the present application can produce customized TDI products with high performance under relatively low energy consumption.

[0030] For example, the source of the first composition is as follows: pure chlorine or chlorine containing bromine is used as raw material to react with carbon monoxide to generate a mixed gas containing phosgene, the mixed gas containing phosgene is reacted with toluene diamine or toluene diamine and phenylene diamine, and the crude TDI is subjected to the process treatment of rectification separation by the refining tower after removing the tar in the reaction liquid to obtain the first composition. Different compositions and contents of the first composition can be obtained by controlling the composition of the reaction raw material or the process conditions.

[0031] Further, the halogen-substituted isocyanate is selected from 4-chloro-6-methyl-m-phenyl diisocyanate 4-bromo-6-methyl-m-phenyl diisocyanate 1-chloromethyl-2,4-diisocyanobenzene 1-bromomethyl-2,4-diisocyanobenzene 1-chloro-2,4-p-phenylene diisocyanate 1-bromo-2,4-p-phenylene diisocyanate 3-dichloroimino-4-methylphenyl isocyanate 3-chloro-4-methylphenyl isocyanate 3-bromo-4-methylphenyl isocyanate 5-chloro-2-methylphenyl isocyanate one or more of 4-chloro-6-methyl-m-phenylene diisocyanate, 4-bromo-6-methyl-m-phenylene diisocyanate, 1-bromomethyl-2,4-diisocyanatobenzene, more preferably 4-chloro-6-methyl-m-phenylene diisocyanate.

[0032] Further, the diisocyanate includes one or more of toluene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate; preferably toluene diisocyanate.

[0033] Further, the NCO content of the polyurethane prepolymer in the A component is 5-10%; preferably 6-8%. The NCO content is the theoretical NCO content.

[0034] Further, the chain extension coefficient of the polyurethane composition is 0.9-0.95.

[0035] In some specific embodiments, the method for preparing the polyurethane prepolymer substituted by halogen includes:

[0036] 1) preheating a composition including the isocyanate substituted by halogen and the diisocyanate not substituted by halogen;

[0037] 2) reacting the preheated composition with the polyol; preferably, the preheating temperature in step 1) is 70-80°C, preferably 75-80°C, and the preheating time is 10-30 min, preferably 15-20 min.

[0038] In step 2), the polyol is metered according to the NCO content of the polyurethane prepolymer substituted by halogen, which is 5-10%, preferably 6-8%.

[0039] The reaction temperature in step 2) is 70-80°C, and the time is 4-6 h, and the reaction is carried out under stirring at a stirring speed of 300-600 rpm; preferably, the reaction temperature is 75-80°C, the time is 4-5 h, and the stirring speed is 400-500 rpm; more preferably, the reaction temperature is 78°C, the time is 5 h, and the stirring speed is 500 rpm.

[0040] In some specific embodiments, the modified polyol chain extender and / or modified polyamine chain extender including halogenated urethane structure include:

[0041] 1) preheating a composition comprising a halogen-substituted isocyanate and a non-halogen-substituted diisocyanate;

[0042] 2) reacting the preheated composition with a polyamine and / or reacting the preheated composition with a polyol; preferably, the preheating temperature of step 1) is 70-80℃, preferably 75-80℃, and the preheating time is 10-30min, preferably 15-20min; the reaction temperature of step 2) is 70-80℃, preferably 75-90℃, and the reaction time is 1-5h.

[0043] In the present application, the composition comprising a halogen-substituted isocyanate and a non-halogen-substituted diisocyanate is not particularly required in terms of its source, for example, it can be obtained by directly mixing TDI with an isocyanate containing a halogen structure, or it can be introduced by enriching an impurity in TDI with an isocyanate containing a halogen structure.

[0044] Preferably, the composition comprising a halogen-substituted isocyanate and a non-halogen-substituted diisocyanate is obtained after being treated by a process of rectification separation by a refining column.

[0045] The rectification separation conditions are: pressure 1-15KPaA, preferably 5-6KPaA, temperature 100-170℃, preferably 130-138℃.

[0046] Preferably, the rectification separation and purification are carried out by a plate column or a structured packing column.

[0047] The present application also provides a polyurethane, the preparation raw material of which comprises any of the polyurethane compositions described above.

[0048] The present application also provides a method for preparing a polyurethane from any of the polyurethane compositions described above, comprising mixing component A with component B, heating and curing to obtain a polyurethane.

[0049] Preferably, the mixing is carried out at a temperature of 80-90℃ and a rotation speed of 200-400rpm, and the mixing time is 5-15min, and the curing temperature is 100-110℃ and the curing time is 18-30h.

[0050] The technical solution of the present application has the following advantages:

[0051] 1. The polyurethane composition provided by the application comprises component A and component B; the component A comprises a halogen-substituted polyurethane prepolymer; the component B comprises a modified polyol chain extender and / or a modified polyamine chain extender which are simultaneously substituted by halogen and urethane, the halogen-substituted polyurethane prepolymer is prepared by selecting a composition containing halogen-substituted isocyanate and non-halogen-substituted diisocyanate and polyol, and the modified polyol chain extender and / or the modified polyamine chain extender which are simultaneously substituted by halogen and urethane are prepared by selecting a composition containing halogen-substituted isocyanate and non-halogen-substituted diisocyanate and polyol, the use of the halogen-substituted polyurethane prepolymer and the modified polyol chain extender and / or the modified polyamine chain extender which are simultaneously substituted by halogen and urethane makes the obtained polyurethane material have excellent tensile strength, elongation at break and flame retardant performance, and can be applied in high-performance working conditions.

[0052] 2. The polyurethane composition provided by the application, wherein the halogen-substituted isocyanate can be derived from impurities in the refining separation process of a TDI device primary refining tower, the application realizes the resource utilization of impurities, and helps to reduce the energy consumption of device operation.

[0053] 3. The polyurethane composition provided by the application, by the modification scheme of the chain extender, the use of the traditional chain extender 3,3'-dichloro-4,4'-diaminodiphenyl methane which is classified as a class 1 carcinogen can be reduced, thereby improving the application construction environment.

[0054] 4. The polyurethane composition provided by the application, by controlling the preparation raw materials of the polyurethane prepolymer: the mass content of the halogen-substituted isocyanate in the composition is 0.1-35%, more preferably 30-35%; the mass content of the non-halogen-substituted diisocyanate is 65-99.9%, more preferably 65%-70%; or, by controlling the preparation raw materials of the modified polyol chain extender and / or the modified polyamine chain extender: the mass content of the halogen-substituted isocyanate in the composition is 0.1-20%, more preferably 15-20%; the mass content of the non-halogen-substituted diisocyanate is 80-99.9%, more preferably 80%-85%; or, by the NCO content of the polyurethane prepolymer being 5-10%, preferably 6-8%, the tensile strength, elongation at break and flame retardant performance of the polyurethane can be further improved.

[0055] 5. The polyurethane provided by the application is prepared by using the polyurethane composition as raw material, and has excellent tensile strength, elongation at break and flame retardant performance, and can be applied in high-performance working conditions. DETAILED DESCRIPTION

[0056] The technical solutions of the application will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the application.

[0057] Unless otherwise indicated, the experimental procedures and conditions in the examples were carried out according to conventional procedures described in the literature. Unless otherwise indicated, the reagents or instruments used were commercially available reagents or instruments.

[0058] Toluene diisocyanate, 1,4-butanediol, Wanhua Chemical Group Co., Ltd.;

[0059] DCB-2000, tetrahydrofuran-propylene oxide copolymer diol with a molecular weight of 2000, Japan Nippon Oil Corporation;

[0060] C2030, polyoxypropylene polyol with a molecular weight of 3000, Wanhua Chemical Group Co., Ltd.;

[0061] Polyethylene glycol-2000, polyoxyethylene polyol with a molecular weight of 2000, American Dow Chemical Company;

[0062] PTMG-1800, polytetrahydrofuran polyol with a molecular weight of 1800, Germany BASF Company;

[0063] 3,3'-dichloro-4,4'-diaminodiphenyl methane, Suzhou Xiangyuan Special Fine Chemical Co., Ltd.;

[0064] 2,4-diamino-3,5-dimethylthio toluene, Linzi Xinglong Chemical Co., Ltd.;

[0065] Ethylene glycol, analytical pure, Shanghai Aladdin Biochemical Technology Co., Ltd.

[0066] The main analysis methods used in the examples and comparative examples of the present application are as follows:

[0067] The first composition composition: using Agilent 7890B type gas chromatography analysis. The processing method of the sample to be measured is as follows: using a disposable dropper to take the sample into a 2mL gas phase vial to the scale line 1.5mL, and then sealing and shaking, and then placing it in the automatic sample injector sample tray corresponding position.

[0068] The gas chromatography conditions are as follows:

[0069] Inlet temperature: 280℃, detector temperature: 300℃, spacer purge: 3mL / min, combustion gas H2 flow rate: 45mL / min; tail blow N2 flow rate: 35mL / min; combustion air flow rate: 300mL / min; split ratio: 10:1; sample size: 0.4μL; gradient flow mode is used, see Table 1, the initial column flow is 1mL / min; degree temperature rise is used, see Table 2.

[0070] Table 1 Gradient flow mode

[0071] Temperature rate °C / min Column flow Hold time Initial 0 1 ml / min 6 min Ramp phase 0.5 ml / min 2 ]] 1 ml / min -> 1.5 ml / min Constant phase 0 1.5 ml / min 20 min

[0072] Table 2 Degree of warming

[0073] Temperature rate °C / min Temperature Hold time Soak phase 0 90℃ 3 min Ramp phase 10 90℃→200℃ Soak phase 0 200℃ 5 min Ramp phase 30 200℃→300℃ Soak phase 0 300℃ 16 min

[0074] The NCO content test of the first composition was performed according to the method of GB / T 12009.4-2016.

[0075] The physical property test method of the polyurethane:

[0076] 1) The oxygen index test of the polyurethane was performed according to the standard of GB / T 2406.2-2009 by using HC-2A limiting oxygen index instrument of Nanjing Jiangning Analysis Instrument Co., Ltd.

[0077] 2) The tensile strength and elongation at break test of the polyurethane was performed according to the standard of GB / T 528-2009 by using KZ-DSC-20 universal testing machine.

[0078] Example 1

[0079] The source of the first composition: the bromine-containing chlorine gas was reacted with carbon monoxide to generate a mixed gas containing phosgene, and the mixed gas containing phosgene was reacted with toluene diamine. After removing the tar from the reaction solution, the crude TDI was separated and purified by a rectification tower to obtain the first composition. The specific steps are as follows:

[0080] The chlorine gas with a bromine content of 1.0wt% and a purity of 99.0wt% measured according to the standard test method of bromine content in chlorine gas of ASTM E649-00(2011) was mixed with carbon monoxide at a molar ratio of 0.8:1 at room temperature, and was sent into a reactor filled with activated carbon. The reaction was carried out at a temperature of 55°C and a pressure of 80kPa gauge to generate a mixed gas containing phosgene.

[0081] The o-dichlorobenzene containing 40wt% toluene diamine was input into the reactor with the above-mentioned mixed gas containing phosgene according to a molar ratio of toluene diamine to phosgene of 1:20. After the reaction, a solution containing 4-bromo-6-methyl-m-phenylene diisocyanate, toluene diisocyanate, o-dichlorobenzene, phosgene and HCl was obtained. The reaction temperature was controlled at 90°C, the operating pressure was 1.5MPa, and the reaction time was 2h. After removing the tar, the first composition containing 4-bromo-6-methyl-m-phenylene diisocyanate and toluene diisocyanate (TDI) and the distillation residue were obtained by separation and purification using a plate rectification tower. The rectification separation conditions were: temperature 100°C, pressure 1.0kPaA, and reflux ratio at the top of the tower 25.

[0082] The first composition was analyzed by gas chromatography and had a composition of 4-bromo-6-methyl-m-phenylene diisocyanate 0.1 wt%, TDI 99.9 wt%. The NCO content of the first composition was 48.08% by potentiometric titration.

[0083] The present embodiment provides a polyurethane composition comprising:

[0084] Preparation of component A: 100 g of the first composition was preheated at 70°C for 10 min, and 468.26 g of DCB-2000 was added. The reaction was stirred at 70°C and 300 rpm for 4 h to obtain a prepolymer with an NCO content of 5%.

[0085] Preparation of component B: 100 g of the first composition was preheated at 70°C for 10 min, and 141.95 g of ethylene glycol (the first composition and the polyol were added according to a molar ratio of NCO to OH of 1:4) was added. The reaction was stirred at 80°C and 400 rpm for 2 h to obtain a modified polyol chain extender.

[0086] The present embodiment also provides a method for preparing a polyurethane from a polyurethane composition, comprising the following steps:

[0087] According to a chain extension coefficient of 0.93, component A and component B were weighed and heated at 80°C. The two components were mixed and stirred at 200 rpm for 5 min, and then cured at 100°C for 18 h to obtain high-strength flame-retardant polyurethane 1.

[0088] Example 2

[0089] Source of the first composition: bromine-containing chlorine gas was reacted with carbon monoxide under super-chlorination conditions to generate a mixed gas containing phosgene. The mixed gas containing phosgene was reacted with toluene diamine and phenyl diamine. After removing the tar from the reaction solution, the crude TDI was separated by rectification in a refining tower to obtain the first composition. The specific steps are as follows:

[0090] Chlorine gas with a bromine content of 17.0 wt% and a purity of 83.0 wt%, measured according to the standard test method for bromine content in chlorine gas in ASTM E649-00 (2011), was mixed with carbon monoxide at a molar ratio of 1.1:1 at room temperature and fed into a reactor filled with activated carbon. The reaction was carried out at a temperature of 55°C and a pressure of 80 kPa gauge to generate a mixed gas containing phosgene.

[0091] A solution containing 20 wt% of toluenediamine and 30 wt% of o-dichlorobenzene solution of phenylenediamine was input into the reactor with the above-mentioned mixed gas containing phosgene according to a molar ratio of toluenediamine to phosgene of 1:15, and a solution containing 1-bromo-2,4-p-phenylene diisocyanate, 1-chloro-2,4-p-phenylene diisocyanate, 3-dichloroimino-4-methylphenyl isocyanate, and TDI, etc. was obtained after the reaction, the reaction temperature was controlled at 90°C, the operating pressure was 1.5 MPa, and the reaction time was 1.2 h; after removing the tar, the first composition containing 1-bromo-2,4-p-phenylene diisocyanate, 1-chloro-2,4-p-phenylene diisocyanate, 3-dichloroimino-4-methylphenyl isocyanate, and TDI, and the distillation residue were separated and purified by using a structured packing column. The rectification separation conditions were: temperature 170°C, pressure 15.0 kPaA, and reflux ratio at the top of the column 30.

[0092] The first composition was analyzed by gas chromatography, and the composition was 1-bromo-2,4-p-phenylene diisocyanate 10.1 wt%, 1-chloro-2,4-p-phenylene diisocyanate 5.3 wt%, 3-dichloroimino-4-methylphenyl isocyanate 0.2 wt%, and TDI 84.4 wt%, and the NCO content of the first composition was 47.56% by potentiometric titration analysis.

[0093] The present embodiment provides a polyurethane composition, which comprises:

[0094] Preparation of component A: 100 g of the first composition was preheated at 80°C for 30 min, 293.44 g of C2O3 was added, and the reaction was stirred at 600 rpm for 6 h at 80°C to prepare a prepolymer containing halogenated carbamic acid structure with an NCO content of 10%.

[0095] Preparation of component B: 100 g of the first composition was preheated at 80°C for 30 min, 509.57 g of 1,4-butanediol (the first composition and the polyol were added according to a molar ratio of NCO to OH of 1:10) was added, and the reaction was stirred at 800 rpm for 5 h at 89°C to prepare a modified polyol chain extender.

[0096] The present embodiment also provides a method for preparing a polyurethane from a polyurethane composition, which comprises the following steps:

[0097] According to a chain extension coefficient of 0.95, component A and component B were weighed, heated at 90°C, and mixed and stirred at a speed of 400 rpm for 15 min, and then cured at 110°C for 30 h to obtain high-strength flame-retardant polyurethane 2.

[0098] Example 3

[0099] The first composition is obtained by the following steps: (1) mixing chlorine gas with bromine content of 12.3wt% and purity of 87.7% measured according to ASTM E649-00(2011) standard test method for bromine content in chlorine gas with carbon monoxide at a molar ratio of 1.2:1 at room temperature, and feeding into a reactor filled with activated carbon to react at a temperature of 55°C and a pressure of 80kPa gauge to generate a mixed gas containing phosgene.

[0100] (1) mixing chlorine gas with bromine content of 12.3wt% and purity of 87.7% measured according to ASTM E649-00(2011) standard test method for bromine content in chlorine gas with carbon monoxide at a molar ratio of 1.2:1 at room temperature, and feeding into a reactor filled with activated carbon to react at a temperature of 55°C and a pressure of 80kPa gauge to generate a mixed gas containing phosgene.

[0101] (2) feeding o-dichlorobenzene containing 30wt% toluene diamine into the reactor according to a molar ratio of toluene diamine to phosgene of 1:13, and obtaining a solution containing 1-chloromethyl-2,4-diisocyanatobenzene, 1-bromomethyl-2,4-diisocyanatobenzene, 3-bromo-4-methylphenyl isocyanate, 3-chloro-4-methylphenyl isocyanate and toluene diisocyanate, o-dichlorobenzene, phosgene, HCl, etc. after reaction, with a reaction temperature of 90°C, an operating pressure of 1.5MPa and a reaction time of 2h; removing tar and separating and purifying by a plate distillation column to obtain the first composition containing 1-chloromethyl-2,4-diisocyanatobenzene, 1-bromomethyl-2,4-diisocyanatobenzene, 3-bromo-4-methylphenyl isocyanate, 3-chloro-4-methylphenyl isocyanate and toluene diisocyanate, and distillation residue. The distillation separation conditions are specifically: at a temperature of 140°C, a pressure of 7.2kPaA and a reflux ratio of 23 at the top of the column.

[0102] The first composition is analyzed by gas chromatography, and the composition is 1-chloromethyl-2,4-diisocyanatobenzene 8.5wt%, 1-bromomethyl-2,4-diisocyanatobenzene 7.5wt%, 3-bromo-4-methylphenyl isocyanate 1.1wt%, 3-chloro-4-methylphenyl isocyanate 0.4wt%, and TDI 82.5wt%. The NCO content of the first composition is 46.29% by potentiometric titration analysis.

[0103] The present embodiment provides a polyurethane composition, which comprises:

[0104] Preparation of component A: 100g of the first composition is preheated at 75°C for 20min, and 313.85g of polyethylene glycol-2000 is added and stirred at 75°C at a speed of 400rpm for 5h to prepare a prepolymer containing halogenated carbamic acid structure with an NCO content of 8%.

[0105] Preparation of B component: 100 g of the first composition was preheated at 75 °C for 15 min, and 882.82 g of 3,3'-dichloro-4,4'-diaminodiphenyl methane (the first composition and the polyamine were added according to a molar ratio of NCO to NH2 of 1:6) was added. The reaction was stirred at 85 °C for 4 h at a rotation speed of 600 rpm to prepare a modified polyamine chain extender.

[0106] The present embodiment also provides a method for preparing a polyurethane from a polyurethane composition, comprising the following steps:

[0107] The A component and the B component were weighed according to a chain extension coefficient of 0.93, heated at 85 °C, and mixed and stirred at a rotation speed of 300 rpm for 10 min. The mixture was cured at 105 °C for 24 h to obtain high-strength flame-retardant polyurethane 3.

[0108] Example 4

[0109] Source of the first composition: chlorogas was used as a raw material to react with carbon monoxide under superchlorination conditions to generate a mixed gas containing phosgene. The mixed gas containing phosgene was reacted with toluene diamine and phenyl diamine. After removing tar from the reaction solution, the crude TDI was separated by rectification in a rectification tower to obtain the first composition. The specific steps are as follows:

[0110] (1) Chlorine gas with a bromine content of 0.01 wt% and a purity of 99.99 wt% measured according to ASTM E649-00 (2011) Standard Test Method for Bromine Content in Chlorine was mixed with carbon monoxide at a molar ratio of 1.5:1.0 at room temperature and fed into a reactor filled with activated carbon. The reaction was carried out at a temperature of 55 °C and a pressure of 80 kPa gauge to generate a mixed gas containing phosgene.

[0111] (2) The o-dichlorobenzene containing 30 wt% toluene diamine was input into the reactor with the above-mentioned mixed gas containing phosgene according to a molar ratio of toluene diamine to phosgene of 1:5. After the reaction, a solution containing 4-chloro-6-methyl-m-phenylene diisocyanate, toluene diisocyanate, o-dichlorobenzene, phosgene, and HCl was obtained. The reaction temperature was controlled at 90 °C, the operating pressure was 1.5 MPa, and the reaction time was 1 h. After removing the tar, the first composition containing 4-chloro-6-methyl-m-phenylene diisocyanate and toluene diisocyanate and the distillation residue were separated and purified by a structured packing column. The rectification separation conditions were as follows: temperature 132 °C, pressure 5.1 kPa A, and reflux ratio at the top of the column 2.

[0112] The first composition was analyzed by gas chromatography, and the composition was 4-chloro-6-methyl-m-phenylene diisocyanate 35 wt% and TDI 65 wt%. The NCO content of the first composition was 41.66% analyzed by potentiometric titration.

[0113] The present embodiment provides a polyurethane composition, comprising:

[0114] Preparation of component A: 100 g of the first composition was preheated at 78 °C for 18 min, and 297.09 g of PTMG-1800 was added. The reaction was stirred at 78 °C and 500 rpm for 5 h to prepare a prepolymer containing halogenated carbamate structure with an NCO content of 7%.

[0115] Preparation of component B: 100 g of the first composition was preheated at 78 °C for 18 min, and 636.8 g of 2,4-diamino-3,5-dimethylthio toluene (the first composition and the polyamine were added according to the molar ratio of NCO to NH2 of 1:6) was added. The reaction was stirred at 88 °C and 800 rpm for 3 h to prepare a modified polyamine chain extender.

[0116] The present embodiment also provides a method for preparing a polyurethane from a polyurethane composition, which comprises the following steps:

[0117] According to the chain extension coefficient of 0.90, component A and component B were weighed and heated at 88 °C. The two components were mixed and stirred at 300 rpm for 15 min, and then cured at 110 °C for 26 h to obtain high-strength flame-retardant polyurethane 4.

[0118] Example 5

[0119] Source of the first composition: chlorogas was used as raw material to react with carbon monoxide under superchlorination conditions to generate a mixed gas containing phosgene. The mixed gas containing phosgene was reacted with toluene diamine and phenyl diamine. After removing tar from the reaction solution, the crude TDI was separated by rectification in a rectification tower to obtain the first composition. The specific steps are as follows:

[0120] (1) Chlorine gas with a bromine content of 0.01 wt% and a purity of 99.99 wt% measured according to ASTM E649-00 (2011) standard test method for bromine content in chlorine was mixed with carbon monoxide at a molar ratio of 1.4:1 at room temperature, and was sent into a reactor filled with activated carbon to react at a temperature of 55 °C and a pressure of 80 kPa gauge to generate a mixed gas containing phosgene.

[0121] (2) The o-dichlorobenzene containing 10 wt% toluene diamine was input into the reactor with the above-mentioned mixed gas containing phosgene according to a molar ratio of toluene diamine to phosgene of 1:8. After reaction, a solution containing 4-chloro-6-methyl-m-phenylene diisocyanate, toluene diisocyanate, o-dichlorobenzene, phosgene and HCl was obtained. The reaction temperature was controlled at 90 °C, the operating pressure was 1.5 MPa, and the reaction time was 0.8 h. After removing tar, the first composition containing 4-chloro-6-methyl-m-phenylene diisocyanate and toluene diisocyanate and distillation residue were separated and purified by a structured packing column. The rectification was carried out at a temperature of 147 °C, a pressure of 8.6 kPa A, and a column top reflux ratio of 5.

[0122] The first composition was analyzed by gas chromatography and had a composition of 4-chloro-6-methyl-m-phenylene diisocyanate 12.5 wt%, TDI 87.5 wt%. The NCO content of the first composition was 43.78% by potentiometric titration.

[0123] The present example provides a polyurethane composition, comprising:

[0124] Preparation of component A: 100 g of the first composition was preheated at 78 °C for 18 min, and 315.26 g of PTMG-1800 was added. The reaction was stirred at 78 °C and 500 rpm for 5 h to obtain a prepolymer containing halogenated carbamic acid ester structure with an NCO content of 7%.

[0125] Preparation of component B: 100 g of the first composition was preheated at 78 °C for 18 min, and 669.21 g of 2,4-diamino-3,5-dimethylthio toluene (the first composition and the polyamine were added according to a molar ratio of NCO to NH2 of 1:6) was added. The reaction was stirred at 88 °C and 800 rpm for 3 h to obtain a modified polyamine chain extender.

[0126] The present example also provides a method for preparing a polyurethane from a polyurethane composition, comprising the following steps:

[0127] According to a chain extension coefficient of 0.90, component A and component B were weighed and heated at 88 °C. The two components were mixed and stirred at 300 rpm for 15 min, and then cured at 110 °C for 26 h to obtain high-strength flame-retardant polyurethane 5.

[0128] Example 6

[0129] The present example provides a polyurethane composition, which is basically the same as example 4, except that the A component and the B component are different. In the preparation process of component A, 309.46 g of DCB-2000 is used instead of “297.09 g of PTMG-1800” in example 4, to obtain a prepolymer containing halogenated carbamic acid ester structure with an NCO content of 7%. In the preparation process of component B, 794.52 g of 3,3'-dichloro-4,4'-diamino diphenyl methane is used instead of “676.56 g of 2,4-diamino-3,5-dimethylthio toluene” in example 4, so that the first composition and the polyamine are added according to a molar ratio of NCO to NH2 of 1:6.

[0130] The present example also provides a method for preparing a polyurethane from a polyurethane composition, which is basically the same as example 4, except that the A component of the present example is used instead of the A component of example 4, and the B component of the present example is used instead of the B component of example 4.

[0131] Example 7

[0132] This example provides a polyurethane compound, which is basically the same as example 4, the difference is only that the A component is different, in the preparation of the A component, the amount of PTMG-1800 is adjusted to 379.24 g, and a prepolymer containing halogenated carbamate structure with an NCO content of 5% is prepared.

[0133] This example also provides a method for preparing a polyurethane from a polyurethane compound, which is basically the same as example 4, the difference is only that the A component of this example is used instead of the A component of example 4.

[0134] Example 8

[0135] This example provides a polyurethane compound, which is basically the same as example 4, the difference is only that the A component is different, in the preparation of the A component, the amount of PTMG-1800 is adjusted to 215.86 g, and a prepolymer containing halogenated carbamate structure with an NCO content of 10% is prepared.

[0136] This example also provides a method for preparing a polyurethane from a polyurethane compound, which is basically the same as example 4, the difference is only that the A component of this example is used instead of the A component of example 4.

[0137] Comparative Example 1

[0138] This comparative example provides a polyurethane compound, which is basically the same as example 1, the difference is only that the A component and the B component are different, in the preparation of the A component, the same mass of toluene diisocyanate is used instead of the "first composition" in example 1, the amount of DCB-2000 is adjusted to 469.35 g, and the rest of the process conditions are the same as example 1, a prepolymer with an NCO content of 5% is prepared; the B component of this comparative example is ethylene glycol.

[0139] This comparative example also provides a method for preparing a polyurethane from a polyurethane compound, which is basically the same as example 1, the difference is only that the A component of this comparative example is used instead of the A component of example 1, and the B component of this comparative example is used instead of the B component of example 1.

[0140] Comparative Example 2

[0141] This comparative example provides a polyurethane compound, which is basically the same as example 3, the difference is only that the B component is different, the B component of this comparative example is 3,3'-dichloro-4,4'-diaminodiphenyl methane.

[0142] This comparative example also provides a method for preparing a polyurethane from a polyurethane compound, which is basically the same as example 3, the difference is only that the B component of this comparative example is used instead of the B component of example 3.

[0143] Comparative Example 3

[0144] The comparative example provides a polyurethane combination material, which is basically the same as that of Example 3, with the only difference being that, in the preparation of the A component, the same mass of toluene diisocyanate is used instead of the "first composition" in Example 3, the amount of polyethylene glycol-2000 is adjusted to 329.51 g, and the rest of the process conditions are the same as those of Example 3, so as to obtain a prepolymer with an NCO content of 8%.

[0145] The comparative example also provides a method for preparing a polyurethane from a polyurethane combination material, which is basically the same as that of Example 3, with the only difference being that the A component of the comparative example is used instead of the A component of Example 3.

[0146] Comparative Example 4

[0147] The comparative example provides a polyurethane combination material, which is basically the same as that of Example 3, with the only difference being that the B component is different, and in the preparation of the B component of the comparative example, the same mass of toluene diisocyanate is used instead of the "first composition" in Example 3, and the amount of 3,3'-dichloro-4,4'-diaminodiphenyl methane is adjusted to 918.88 g, so that the toluene diisocyanate and the polyol are fed according to an NCO to NH2 molar ratio of 1:6.

[0148] The comparative example also provides a method for preparing a polyurethane from a polyurethane combination material, which is basically the same as that of Example 3, with the only difference being that the B component of the comparative example is used instead of the B component of Example 3.

[0149] The tensile strength, elongation at break, and limiting oxygen index of the polyurethane prepared in each example and comparative example are tested, and the test results are shown in Table 3 below:

[0150] Table 3 Test results of polyurethane properties

[0151] Performance indicators Limiting oxygen index / % Tensile strength / MPa Elongation at break / % Example 1 24.8 45 680 Example 2 26.2 50 723 Example 3 28.7 57 702 Example 4 30.1 65 796 Example 5 25.9 58 691 Example 6 28.9 62 753 Example 7 25.7 60 713 Example 8 26.7 61 708 Comparative Example 1 21.8 32 633 Comparative Example 2 24.1 37 650 Comparative Example 3 22.7 41 667 Comparative Example 4 24.3 44 661

[0152] As can be seen from the performance test results in Table 3, the preparation method of the polyurethane combination material mentioned in the present application can obtain a polyurethane material with greatly improved tensile strength, elongation at break, and flame retardant performance.

[0153] The performance of examples 1-4 is all better than that of comparative example 1 polyurethane prepared by using toluene diisocyanate and conventional chain extender ethylene glycol. Compared with comparative example 2 and example 3, the prepolymer component is prepared according to the scheme of the present application, and the other component selects a conventional chain extender which is not modified, and the flame retardant performance is improved by one grade, but the mechanical property is improved by a smaller range. Compared with comparative example 3 and example 3, the prepolymer component is modified for toluene diisocyanate pure product, and the chain extender component is prepared according to the scheme of the present application, and the improvement degree of the material flame retardant performance is limited, but the tensile strength and elongation at break are significantly increased, which shows that the modification of the prepolymer component in the scheme of the present application plays a more important role in improving the flame retardant performance, the modification of the chain extender component contributes more to the improvement of the mechanical property of the material, and the synergistic effect obtains polyurethane material with good mechanical property and flame retardant performance.

[0154] Compared with examples 1-5, examples 2-4 can further improve the mechanical property and flame retardant performance of polyurethane by controlling the mass content of isocyanate substituted by halogen or diisocyanate not substituted by halogen in the A composition or the B composition within the preferred range. Examples 3-4 can further improve the mechanical property and flame retardant performance of polyurethane by limiting the NCO content of the prepolymer within the preferred range.

[0155] Compared with example 4 and example 6, example 4 further improves the mechanical property and flame retardant performance of polyurethane by using polytetrahydrofuran polyol with a molecular weight of 400-2000.

[0156] Compared with example 4 and examples 7 and 8, example 4 further improves the mechanical property and flame retardant performance of polyurethane by controlling the NCO content of the prepolymer containing halogenated urethane structure within the preferred range.

[0157] Obviously, the above examples are only examples for clearly illustrating, and not limit the embodiments. For those skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, it is not necessary and impossible to enumerate all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A polyurethane compound, characterized in that, The polyurethane composite material includes component A and component B; Component A includes a halogen-substituted polyurethane prepolymer; Component B includes modified polyol chain extenders and / or modified polyamine chain extenders that are simultaneously substituted with halogens and carbamates. The raw materials for preparing the halogen-substituted polyurethane prepolymer include a composition containing halogen-substituted isocyanate and unsubstituted diisocyanate, and a polyol selected from one or more of polyethylene oxide polyol, polypropylene oxide polyol, polytetrahydrofuran polyol, and tetrahydrofuran-propylene oxide copolydiol. The raw materials for preparing the modified polyamine chain extender include a composition containing a halogen-substituted isocyanate and an unsubstituted diisocyanate, as well as a small molecule polyamine. The raw materials for preparing the modified polyol chain extender include a composition containing a halogen-substituted isocyanate and an unsubstituted diisocyanate, as well as a small molecule polyol.

2. The polyurethane compound according to claim 1, characterized in that, In the raw materials for preparing the halogen-substituted polyurethane prepolymer, the mass content of the halogen-substituted isocyanate in the composition is 0.1-35%.

3. The polyurethane compound according to claim 2, characterized in that, In the raw materials for preparing the halogen-substituted polyurethane prepolymer, the mass content of the halogen-substituted isocyanate in the composition is 30-35%.

4. The polyurethane compound according to claim 1, characterized in that, In the raw materials for preparing the modified polyamine chain extender, the composition contains 65-99.9% by mass of unsubstituted diisocyanate.

5. The polyurethane compound according to claim 4, characterized in that, In the raw materials for preparing the modified polyamine chain extender, the composition contains 65%-70% by mass of unsubstituted diisocyanate.

6. The polyurethane compound according to claim 1, characterized in that, In the raw materials for preparing the modified polyamine chain extender, the polyol is polytetrahydrofuran polyol.

7. The polyurethane compound according to claim 6, characterized in that, In the raw materials for preparing the modified polyamine chain extender, the polyol is a polytetrahydrofuran polyol with a molecular weight of 400-2000.

8. The polyurethane compound according to claim 1, characterized in that, In the raw materials for preparing the modified polyamine chain extender, the mass content of the halogen-substituted isocyanate in the composition is 0.1-20%.

9. The polyurethane compound according to claim 8, characterized in that, In the raw materials for preparing the modified polyamine chain extender, the mass content of halogen-substituted isocyanate in the composition is 15-20%.

10. The polyurethane compound according to claim 1, characterized in that, In the raw materials for preparing the modified polyamine chain extender, in the raw materials for preparing the modified polyol chain extender, and in the composition, the mass content of unsubstituted diisocyanate is 80-99.9%.

11. The polyurethane compound according to claim 10, characterized in that, In the raw materials for preparing the modified polyamine chain extender, in the raw materials for preparing the modified polyol chain extender, and in the composition, the mass content of unsubstituted diisocyanate is 80%-85%.

12. The polyurethane compound according to claim 1, characterized in that, In the raw materials for preparing the modified polyamine chain extender, the small molecule polyamine is selected from one or more of 3,3'-dichloro-4,4'-diaminodiphenylmethane, 2,4-diamino-3,5-dimethylthiotoluene, and melamine.

13. The polyurethane compound according to claim 12, characterized in that, In the raw materials for preparing the modified polyamine chain extender, the small molecule polyamine is 2,4-diamino-3,5-dimethylthiotoluene.

14. The polyurethane compound according to claim 1, characterized in that, In the preparation of the modified polyamine chain extender, the composition and polyamine are fed in a molar ratio of NCO to NH2 of 1:4-10.

15. The polyurethane compound according to claim 14, characterized in that, In the preparation raw materials of the modified polyamine chain extender, the composition and polyamine are fed in a molar ratio of NCO to NH2 of 1:5-6.

16. The polyurethane compound according to claim 1, characterized in that, In the raw materials for preparing the modified polyol chain extender, the mass content of the halogen-substituted isocyanate in the composition is 0.1-20%.

17. The polyurethane compound according to claim 16, characterized in that, In the raw materials for preparing the modified polyol chain extender, the mass content of the halogen-substituted isocyanate in the composition is 15-20%.

18. The polyurethane compound according to claim 1, characterized in that, In the raw materials for preparing the modified polyol chain extender, the composition contains 80-99.9% by mass of unsubstituted diisocyanate.

19. The polyurethane compound according to claim 18, characterized in that, In the raw materials for preparing the modified polyol chain extender, the composition contains 80%-85% by mass of unsubstituted diisocyanate.

20. The polyurethane compound according to claim 1, characterized in that, In the preparation of the modified polyol chain extender, the small molecule polyol is selected from one or more of ethylene glycol, 1,4-butanediol, and trimethylolpropane.

21. The polyurethane compound according to claim 1, characterized in that, In the preparation of the modified polyol chain extender, the composition and the small molecule polyol are fed in a molar ratio of NCO to OH of 1:4-10.

22. The polyurethane compound according to claim 21, characterized in that, In the preparation of the modified polyol chain extender, the composition and the small molecule polyol are fed in a molar ratio of NCO to OH of 1:5-6.

23. The polyurethane compound according to any one of claims 1-22, characterized in that, The halogen-substituted isocyanate is selected from one or more of 4-chloro-6-methyl-m-phenyl diisocyanate, 4-bromo-6-methyl-m-phenyl diisocyanate, 1-chloromethyl-2,4-diisocyanophenyl, 1-bromomethyl-2,4-diisocyanophenyl, 1-chloro-2,4-p-phenyl diisocyanate, 1-bromo-2,4-p-phenyl diisocyanate, 3-dichloroimino-4-methylphenyl isocyanate, 3-chloro-4-methylphenyl isocyanate, 3-bromo-4-methylphenyl isocyanate, and 5-chloro-2-methylphenyl isocyanate.

24. The polyurethane compound according to claim 23, characterized in that, The halogen-substituted isocyanate is selected from one or more of 4-chloro-6-methyl-m-phenyl diisocyanate, 4-bromo-6-methyl-m-phenyl diisocyanate, and 1-bromomethyl-2,4-diisocyanobenzene.

25. The polyurethane compound according to claim 24, characterized in that, The halogen-substituted isocyanate is 4-chloro-6-methyl-m-phenyl diisocyanate.

26. The polyurethane compound according to any one of claims 1-22, characterized in that, The unsubstituted halogen diisocyanate includes one or more of toluene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, phenyl dimethylene diisocyanate, and hexamethylene diisocyanate.

27. The polyurethane compound according to claim 1, characterized in that, The NCO content of the polyurethane prepolymer in component A is 5-10%.

28. The polyurethane compound according to claim 1, characterized in that, The NCO content of the polyurethane prepolymer in component A is 6-8%.

29. The polyurethane compound according to claim 1, characterized in that, The chain extension coefficient of the polyurethane compound is 0.9~0.

95.

30. A polyurethane, characterized in that, The raw materials for its preparation include any of the polyurethane blends described in claims 1-29.

31. A method for preparing polyurethane from any of the polyurethane blends according to claims 1-29, characterized in that, This includes mixing component A and component B, heating and curing to obtain the final product.

32. The method for preparing polyurethane from polyurethane compound according to claim 31, wherein the mixture is carried out at a temperature of 80-90℃ and a rotation speed of 200-400 rpm for 5-15 min, the curing temperature is 100-110℃, and the curing time is 18-30 h.