Polyurethane composite material, polyurethane and preparation method thereof

Abstract

The invention relates to the field of polyurethane elastomer materials, in particular to a polyurethane composite material, polyurethane and a preparation method of the polyurethane composite material, and the polyurethane composite material comprises a component A and a 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 / is substituted by halogen and carbamate at the same time; a composition containing a halogen-substituted isocyanate and a halogen-unsubstituted diisocyanate is selected to prepare a halogen-substituted polyurethane prepolymer with a polyol, and a modified polyol chain extender and / or a modified polyamine chain extender, which are / is substituted by both halogen and carbamate, are / is used together. Therefore, the obtained polyurethane material has excellent tensile strength, elongation at break and flame retardant property at the same time.

Description

Technical Field

[0001] The invention relates to the field of polyurethane materials, and in particular to a polyurethane composite material, polyurethane and a preparation method thereof. Background Art

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

[0003] The combination materials for producing polyurethane are highly designable and adjustable. From formula design to molding process, they can be flexibly adjusted according to specific requirements to adapt to the needs of different fields and environments. They have become high-performance materials that are highly favored in the field of material application. At the same time, as polyurethane combination materials penetrate into more fields, harsh use environments have put forward higher strength requirements for polyurethane combination materials. The inherent flammability of polyurethane itself is also one of the main problems in using such materials. It is very easy to burn in a fire environment, generating a large amount of heat, smoke and toxic gases, causing serious damage to the construction and application environment. Therefore, the mechanical properties and flame retardant properties of polyurethane combination materials have attracted more attention from researchers in related fields.

[0004] The means to improve the flame retardant properties of polyurethane composite materials are generally to physically mix reactive flame retardants or additive flame retardants. However, studies have shown that simple physical mixing of flame retardants will affect the mechanical properties of the material. Liquid flame retardants have a significant plasticizing effect on the material itself, increasing the spacing between molecular chains and weakening the hydrogen bonding between molecules, thereby reducing the mechanical properties; after the addition of 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, they will produce stress concentration points, making it easier to break, affecting the strength of the material.

[0005] Therefore, in response to the current problems and development trends faced by the industry, it is urgent to develop a modification path that can simultaneously improve the mechanical properties and flame retardant properties of polyurethane materials. Summary of the invention

[0006] Therefore, the object of the present invention is to provide a polyurethane composite material, a polyurethane and a preparation method thereof. By using two components consisting of a polyurethane prepolymer substituted by halogen and a modified polyol chain extender and / or a modified polyamine chain extender substituted by both halogen and carbamate, a halogen that can serve as a combustion reaction chain terminator is introduced while ensuring the degree of reaction, and the crosslinking degree of the modified chain extender is greatly increased compared to the traditional chain extender, thereby achieving the simultaneous improvement of the mechanical properties and flame retardant properties of the polyurethane material.

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

[0008] Component A includes a halogen-substituted polyurethane prepolymer;

[0009] The B component includes a modified polyol chain extender and / or a modified polyamine chain extender substituted with both halogen and urethane.

[0010] Furthermore, the raw materials for preparing the halogen-substituted polyurethane prepolymer include a composition containing a halogen-substituted isocyanate and a diisocyanate not substituted by halogen, 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 diisocyanate not substituted by halogen is 65-99.9%, more preferably 65%-70%;

[0013] Preferably, the polyol is selected from one or more of polyethylene oxide polyol, polypropylene oxide polyol, polytetramethylene glycol, tetramethylene oxide-propylene oxide copolymer glycol, preferably polytetramethylene glycol, more preferably polytetramethylene glycol having a molecular weight of 400-2000.

[0014] Furthermore, the raw materials for preparing the modified polyamine chain extender include a composition containing a halogen-substituted isocyanate and a halogen-unsubstituted 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 diisocyanate not substituted by halogen is 80-99.9%, more preferably 80%-85%;

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

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

[0019] Furthermore, the raw materials for preparing the modified polyol chain extender include a composition of a halogen-substituted isocyanate and a halogen-unsubstituted diisocyanate and a polyol;

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

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

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

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

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

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

[0026] The present invention selects a composition containing halogen-substituted isocyanate and non-halogen-substituted diisocyanate and polyol to prepare a halogen-substituted polyurethane prepolymer, and also uses a composition containing halogen-substituted isocyanate and non-halogen-substituted diisocyanate to modify the chain extender component respectively. The halogen structure can be decomposed to generate hydrogen halide at the combustion temperature, and the circulation of hydrogen halide can terminate the combustion chain reaction; the residue after decomposing hydrogen halide under combustion conditions can promote the dehydration and carbonization of the material, form a non-flammable carbonization layer, reduce the generation 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 progress of the combustion reaction. The large amount of halogen structure introduced in the present invention significantly improves the flame retardant properties of the polyurethane material.

[0027] The present invention experimentally found that a traditional small molecule chain extender is modified with a composition containing a halogen-substituted isocyanate and a halogen-unsubstituted diisocyanate. During the mixing and curing stage, a long chain structure containing a carbamate bond in the modified chain extender is interspersed in a polyurethane network, and when the polyurethane is damaged by the outside world, energy can be dispersed in the material to reduce stress concentration. Based on the linking effect that the small molecule chain extender can provide, the modified chain extender can also be entangled and stacked between molecular chains after being introduced into the main chain, thereby improving the compactness of the structure, significantly improving the cross-linking strength and stretchability of the polyurethane, and improving the tensile strength and toughness of the polyurethane prepared from the combined material.

[0028] The present invention has experimentally found that the refined TDI extracted from the TDI refining tower can be treated by a distillation separation process to obtain a composition containing halogen-substituted isocyanate (or isocyanate containing a halogen structure) and TDI in different contents. Since the isocyanate containing a halogen structure 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 other types of additives, so a higher addition amount can be provided to improve various performances.

[0029] The technicians of the present invention have found that during the production process, the content of TDI and other isocyanates in the first composition is controlled by controlling raw material indicators, multiple distillation purification or separation and extraction, so as to ensure the activity of the product in downstream applications. This undoubtedly puts strict requirements on the refining / separation capacity and operating conditions of the production equipment. The application of TDI containing halogen structure in the present invention can produce high-performance customized TDI products with 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 a raw material to react with carbon monoxide to generate a mixed gas containing phosgene, the mixed gas containing phosgene reacts with toluene diamine or with toluene diamine and phenylenediamine, and the reaction liquid is treated with a process of removing tar from crude TDI and separating it by distillation in a refining tower to obtain the first composition. The first composition with different compositions and contents can be obtained by controlling the composition of the reaction raw materials 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-phenylene diisocyanate 1-Bromo-2,4-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, preferably 4-chloro-6-methyl-m-phenyl diisocyanate, 4-bromo-6-methyl-m-phenyl diisocyanate, one or more of 1-bromomethyl-2,4-diisocyanobenzene, more preferably 4-chloro-6-methyl-m-phenyl diisocyanate.

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

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

[0034] Furthermore, the chain extension coefficient of the polyurethane composite material is 0.9 to 0.95.

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

[0036] 1) preheating a composition comprising a halogen-substituted isocyanate and a halogen-unsubstituted diisocyanate;

[0037] 2) reacting the preheated composition with a polyol to obtain a product; 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] Wherein, in step 2), the metered polyol is designed according to the NCO content of the halogen-substituted polyurethane prepolymer being 5-10%, preferably the NCO content being 6-8%.

[0039] Step 2) The reaction temperature is 70-80°C, the time is 4-6h, the reaction is carried out under stirring, and the stirring speed is 300-600rpm. Preferably, the reaction temperature is 75-80°C, the time is 4-5h, and the stirring speed is 400-500rpm. More preferably, the reaction temperature is 78°C, the time is 5h, and the stirring speed is 500rpm.

[0040] In some specific embodiments, the modified polyol chain extender and / or modified polyamine chain extender containing a halogenated carbamate structure includes:

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

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

[0043] In the present invention, the composition comprising halogen-substituted isocyanate and non-halogen-substituted diisocyanate has no special requirement on its source. For example, it can be obtained by directly mixing TDI with halogen-containing isocyanate, or by introducing halogen-containing isocyanate through enrichment of impurities in TDI.

[0044] Preferably, the composition comprising the halogen-substituted isocyanate and the halogen-unsubstituted diisocyanate is obtained by treatment with a rectification and separation process in a refining tower.

[0045] Wherein, the distillation separation conditions are: pressure 1-15KPaA, preferably 5-6KPaA, temperature 100-170°C, preferably 130-138°C.

[0046] Preferably, the distillation separation and purification is carried out by a plate tower or a structured packing tower.

[0047] The present invention also provides a polyurethane, the raw materials for preparing the polyurethane include any of the polyurethane composite materials described above.

[0048] The present invention also provides a method for preparing polyurethane from any of the above-mentioned polyurethane combinations, comprising: mixing component A with component B, heating and curing, to obtain;

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

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

[0051] 1. The polyurethane composition provided by the present invention comprises component A and component B; component A comprises a halogen-substituted polyurethane prepolymer; component B comprises a modified polyol chain extender and / or a modified polyamine chain extender substituted with both halogen and carbamate; by selecting a composition containing a halogen-substituted isocyanate and a diisocyanate not substituted with a halogen and using the polyol to prepare a halogen-substituted polyurethane prepolymer and the modified polyol chain extender and / or the modified polyamine chain extender substituted with both halogen and carbamate, the obtained polyurethane material has excellent tensile strength, elongation at break and flame retardancy, and can be used in working conditions requiring high performance.

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

[0053] 3. The polyurethane composite material provided by the present invention can reduce the use of the traditional chain extender 3,3'-dichloro-4,4'-diaminodiphenylmethane, which is classified as a Class 1 carcinogen, through a modification scheme of the chain extender, thereby improving the application and construction environment.

[0054] 4. The polyurethane composition provided by the present invention can further improve the tensile strength, elongation at break and flame retardant properties of polyurethane by controlling the raw materials for preparing the polyurethane prepolymer: the mass content of halogen-substituted isocyanate in the composition is 0.1-35%, more preferably 30-35%; the mass content of diisocyanate not substituted by halogen is 65-99.9%, more preferably 65%-70%; or, controlling the raw materials for preparing the modified polyol chain extender and / or modified polyamine chain extender: the mass content of halogen-substituted isocyanate in the composition is 0.1-20%, more preferably 15-20%; the mass content of diisocyanate not substituted by halogen is 80-99.9%, more preferably 80%-85%; or, by adjusting the NCO content of the polyurethane prepolymer to 5-10%, preferably 6-8%.

[0055] 5. The polyurethane provided by the present invention is prepared using a polyurethane composite material as a raw material. The obtained polyurethane has excellent tensile strength, elongation at break and flame retardancy, and can be used under working conditions requiring high performance. DETAILED DESCRIPTION

[0056] The technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are only 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.

[0057] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

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

[0059] DCB-2000, tetrahydrofuran-propylene oxide copolymer with a molecular weight of 2000, NOF Corporation;

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

[0061] Polyethylene glycol-2000, a polyethylene glycol with a molecular weight of 2000, from The Dow Chemical Company, USA;

[0062] PTMG-1800, polytetramethylene glycol with a molecular weight of 1800, BASF, Germany;

[0063] 3,3'-Dichloro-4,4'-diaminodiphenylmethane, Suzhou Xiangyuan Special Fine Chemical Co., Ltd.;

[0064] 2,4-Diamino-3,5-dimethylthiotoluene, Linzi Xinlong Chemical Co., Ltd.;

[0065] Ethylene glycol, analytical grade, was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

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

[0067] The first composition is composed of: Agilent 7890B gas chromatograph is used for analysis. The processing method of the sample to be tested is as follows: use a disposable dropper to draw the sample into a 2mL gas phase vial to the scale line of 1.5mL, cover it, shake it well, and then put it into the corresponding position of the sample tray of the automatic sampler.

[0068] The gas chromatography conditions were as follows:

[0069] Inlet temperature: 280℃, detector temperature: 300℃, septum purge: 3mL / min, combustion gas H2 flow rate: 45mL / min; tail blow N2 flow rate: 35mL / min; combustion gas air flow rate: 300mL / min; split ratio: 10:1; injection volume: 0.4μL; gradient flow mode, as shown in Table 1, initial column flow rate is 1mL / min; gradual temperature increase, as shown in Table 2.

[0070] Table 1 Gradient flow mode

[0071] Heating rate℃ / min Column flow Keep Time initial 0 1ml / min 6min Speed-up phase <![CDATA[0.5ml / min 2 ]]> 1ml / min→1.5ml / min Constant speed stage 0 1.5ml / min 20min

[0072] Table 2 Degree of temperature rise

[0073] Heating rate℃ / min temperature Keep Time Insulation stage 0 90℃ 3min Heating stage 10 90℃→200℃ Insulation stage 0 200℃ 5min Heating stage 30 200℃→300℃ Insulation stage 0 300℃ 16min

[0074] The NCO content of the first composition is tested using the GB / T 12009.4-2016 method.

[0075] Physical property test methods of polyurethane:

[0076] 1) The polyurethane oxygen index test is carried out using the HC-2A limiting oxygen index instrument produced by Nanjing Jiangning Analytical Instrument Co., Ltd. in accordance with GB / T 2406.2-2009 standard;

[0077] 2) The tensile strength and elongation at break of polyurethane were tested using a KZ-DSC-20 universal testing machine in accordance with GB / T528-2009 standard.

[0078] Example 1

[0079] The source of the first composition is: using chlorine gas containing bromine as a raw material to react with carbon monoxide to generate a mixed gas containing phosgene, the mixed gas containing phosgene reacts with toluene diamine, and the reaction liquid is treated with a process of removing tar from crude TDI through a refining tower for distillation separation to obtain the first composition. The specific steps are:

[0080] Chlorine gas with a bromine content of 1.0 wt% and a purity of 99.0 wt% measured according to the standard test method for 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 sent into a reactor filled with activated carbon to react at a temperature of 55° C. and a pressure of 80 kPa gauge pressure to generate a mixed gas containing phosgene.

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

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

[0083] This embodiment provides a polyurethane composite material, including:

[0084] Preparation of component A: Weigh 100 g of the first composition and preheat it at 70° C. for 10 min, add 468.26 g of DCB-2000, and stir at 70° C. and 300 rpm for 4 h to prepare a prepolymer with an NCO content of 5%.

[0085] Preparation of component B: weigh 100 g of the first composition and preheat it at 70°C for 10 min, add 141.95 g of ethylene glycol (the first composition and the polyol are added at a molar ratio of NCO to OH of 1:4), stir and react at 80°C at 400 rpm for 2 h to prepare a modified polyol chain extender.

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

[0087] Component A and component B were weighed according to a chain extension coefficient of 0.93, heated at 80° C., mixed and stirred at 200 rpm for 5 minutes, and cured at 100° C. for 18 hours to obtain a high-strength flame-retardant polyurethane 1.

[0088] Example 2

[0089] The source of the first composition is: using chlorine gas containing bromine as a raw material to react with carbon monoxide under a perchlorine condition to generate a mixed gas containing phosgene, the mixed gas containing phosgene reacts with toluenediamine and phenylenediamine, and the reaction liquid is treated with a process of removing tar from crude TDI by distillation separation in a refining tower to obtain the first composition. The specific steps are:

[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 of ASTM E649-00 (2011) was mixed with carbon monoxide at a molar ratio of 1.1:1 at room temperature, and sent into a reactor filled with activated carbon to react at a temperature of 55° C. and a pressure of 80 kPa gauge pressure to generate a mixed gas containing phosgene.

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

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

[0093] This embodiment provides a polyurethane composite material, including:

[0094] Preparation of component A: Weigh 100 g of the first composition and preheat it at 80° C. for 30 min, add 293.44 g of C2030, and react at 80° C. and 600 rpm for 6 h to prepare a prepolymer containing a halogenated carbamate structure and having an NCO content of 10%.

[0095] Preparation of component B: weigh 100 g of the first composition and preheat it at 80° C. for 30 min, add 509.57 g of 1,4-butanediol (the first composition and the polyol are added at a molar ratio of NCO to OH of 1:10), stir and react at 89° C. at 800 rpm for 5 h to prepare a modified polyol chain extender.

[0096] This embodiment also provides a method for preparing polyurethane from a polyurethane composition, comprising the following steps:

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

[0098] Example 3

[0099] The source of the first composition is: using chlorine gas containing bromine as a raw material to react with carbon monoxide under a perchlorine condition to generate a mixed gas containing phosgene, the mixed gas containing phosgene reacts with toluenediamine and phenylenediamine, and the reaction liquid is treated with a process of removing tar from crude TDI by distillation separation in a refining tower to obtain the first composition. The specific steps are:

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

[0101] (2) o-dichlorobenzene containing 30 wt% of toluenediamine and the above-mentioned mixed gas containing phosgene are introduced into a reactor at a molar ratio of toluenediamine to phosgene of 1:13, and after reaction, a solution containing 1-chloromethyl-2,4-diisocyanobenzene, 1-bromomethyl-2,4-diisocyanobenzene, 3-bromo-4-methylphenylisocyanate, 3-chloro-4-methylphenylisocyanate and toluene diisocyanate, o-dichlorobenzene, phosgene, HCl, etc. is obtained. The reaction temperature is controlled at 90° C., the operating pressure is 1.5 MPa, and the reaction time is 2 h. After removing tar, separation and purification are performed using a plate distillation tower to obtain a first composition containing 1-chloromethyl-2,4-diisocyanobenzene, 1-bromomethyl-2,4-diisocyanobenzene, 3-bromo-4-methylphenylisocyanate, 3-chloro-4-methylphenylisocyanate and toluene diisocyanate and a distillation residue. The specific distillation separation conditions are: temperature 140°C, pressure 7.2 kPaA, and top reflux ratio 23.

[0102] Gas chromatography analysis of the first composition showed that the composition was 8.5 wt% of 1-chloromethyl-2,4-diisocyanobenzene, 7.5 wt% of 1-bromomethyl-2,4-diisocyanobenzene, 1.1 wt% of 3-bromo-4-methylphenylisocyanate, 0.4 wt% of 3-chloro-4-methylphenylisocyanate, and 82.5 wt% of TDI. Potentiometric titration analysis showed that the NCO content of the first composition was 46.29%.

[0103] This embodiment provides a polyurethane composite material, including:

[0104] Preparation of component A: Weigh 100 g of the first composition and preheat it at 75° C. for 20 min, add 313.85 g of polyethylene glycol-2000, and stir at 75° C. and 400 rpm for 5 h to prepare a prepolymer containing a halogenated carbamate structure with an NCO content of 8%.

[0105] Preparation of component B: weigh 100 g of the first composition and preheat it at 75°C for 15 min, add 882.82 g of 3,3'-dichloro-4,4'-diaminodiphenylmethane (the first composition and the polyamine are added at a molar ratio of NCO to NH2 of 1:6), stir and react at 85°C at 600 rpm for 4 h to prepare a modified polyamine chain extender.

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

[0107] Component A and component B were weighed according to a chain extension coefficient of 0.93, heated at 85°C, mixed and stirred at 300 rpm for 10 minutes, and cured at 105°C for 24 hours to obtain high-strength flame-retardant polyurethane 3.

[0108] Example 4

[0109] The source of the first composition is: using chlorine as a raw material to react with carbon monoxide under a perchlorine condition to generate a mixed gas containing phosgene, the mixed gas containing phosgene reacts with toluenediamine and phenylenediamine, and the reaction liquid is treated with a process of removing tar from crude TDI through a refining tower for distillation separation to obtain the first composition. The specific steps are:

[0110] (1) Chlorine gas having a bromine content of 0.01 wt% and a purity of 99.99 wt% measured according to the standard test method for bromine content in chlorine gas of ASTM E649-00 (2011) and carbon monoxide in a molar ratio of 1.5:1.0 is mixed at room temperature and fed into a reactor filled with activated carbon to react at a temperature of 55° C. and a pressure of 80 kPa gauge pressure to generate a mixed gas containing phosgene.

[0111] (2) o-dichlorobenzene containing 30 wt% toluenediamine and the above-mentioned mixed gas containing phosgene are input into a reactor at a molar ratio of toluenediamine to phosgene of 1:5, and a solution containing 4-chloro-6-methyl-m-phenyl diisocyanate, toluene diisocyanate, o-dichlorobenzene, phosgene, and HCl is obtained after the reaction. The reaction temperature is controlled at 90°C, the operating pressure is 1.5 MPa, and the reaction time is 1 hour; after removing the tar, a first composition containing 4-chloro-6-methyl-m-phenyl diisocyanate and toluene diisocyanate and a distillation residue are obtained by separation and purification using a structured packing tower. The specific distillation separation conditions are: at a temperature of 132°C, a pressure of 5.1 kPaA, and a tower top reflux ratio of 2.

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

[0113] This embodiment provides a polyurethane composite material, including:

[0114] Preparation of component A: Weigh 100 g of the first composition and preheat it at 78° C. for 18 min, add 297.09 g of PTMG-1800, and stir at 78° C. and 500 rpm for 5 h to prepare a prepolymer containing a halogenated carbamate structure and having an NCO content of 7%.

[0115] Preparation of component B: weigh 100 g of the first composition and preheat it at 78°C for 18 min, add 636.8 g of 2,4-diamino-3,5-dimethylthiotoluene (the first composition and the polyamine are added at a molar ratio of NCO to NH2 of 1:6), stir and react at 88°C at 800 rpm for 3 h to prepare a modified polyamine chain extender.

[0116] This embodiment also provides a method for preparing polyurethane from a polyurethane composition, comprising the following steps:

[0117] Component A and component B were weighed according to a chain extension coefficient of 0.90, heated at 88°C, mixed and stirred at 300 rpm for 15 minutes, and cured at 110°C for 26 hours to obtain high-strength flame-retardant polyurethane 4.

[0118] Example 5

[0119] The source of the first composition is: using chlorine as a raw material to react with carbon monoxide under a perchlorine condition to generate a mixed gas containing phosgene, the mixed gas containing phosgene reacts with toluenediamine and phenylenediamine, and the reaction liquid is treated with a process of removing tar from crude TDI through a refining tower for distillation separation to obtain the first composition. The specific steps are:

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

[0121] (2) o-dichlorobenzene containing 10 wt% toluenediamine and the above-mentioned mixed gas containing phosgene are input into a reactor at a molar ratio of toluenediamine to phosgene of 1:8, and a solution containing 4-chloro-6-methyl-m-phenyl diisocyanate, toluene diisocyanate, o-dichlorobenzene, phosgene, and HCl is obtained after the reaction. The reaction temperature is controlled at 90°C, the operating pressure is 1.5 MPa, and the reaction time is 0.8 h; after removing the tar, a first composition containing 4-chloro-6-methyl-m-phenyl diisocyanate and toluene diisocyanate and a distillation residue are obtained by separation and purification using a structured packing tower. The distillation is specifically: at a temperature of 147°C, a pressure of 8.6 kPaA, and a tower top reflux ratio of 5.

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

[0123] This embodiment provides a polyurethane composite material, including:

[0124] Preparation of component A: Weigh 100 g of the first composition and preheat it at 78° C. for 18 min, add 315.26 g of PTMG-1800, and stir at 78° C. and 500 rpm for 5 h to prepare a prepolymer containing a halogenated carbamate structure and having an NCO content of 7%.

[0125] Preparation of component B: weigh 100 g of the first composition and preheat it at 78°C for 18 min, add 669.21 g of 2,4-diamino-3,5-dimethylthiotoluene (the first composition and the polyamine are added at a molar ratio of NCO to NH2 of 1:6), stir and react at 88°C at 800 rpm for 3 h to prepare a modified polyamine chain extender.

[0126] This embodiment also provides a method for preparing polyurethane from a polyurethane composition, comprising the following steps:

[0127] Component A and component B were weighed according to a chain extension coefficient of 0.90, heated at 88° C., mixed and stirred at 300 rpm for 15 minutes, and cured at 110° C. for 26 hours to obtain a high-strength flame-retardant polyurethane 5.

[0128] Example 6

[0129] This embodiment provides a polyurethane composition material, which is basically the same as Example 4, except that component A and component B are different. During the preparation of component A, 309.46 g of DCB-2000 is used instead of "297.09 g of PTMG-1800" in Example 4 to prepare a prepolymer containing a halogenated carbamate structure with an NCO content of 7%. During the preparation of component B, 794.52 g of 3,3'-dichloro-4,4'-diaminodiphenylmethane is used instead of "676.56 g of 2,4-diamino-3,5-dimethylthiotoluene" in Example 4, so that the first composition and the polyamine are fed according to a molar ratio of NCO to NH2 of 1:6.

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

[0131] Example 7

[0132] This embodiment provides a polyurethane composition, which is basically the same as that of Embodiment 4, except that component A is different. During the preparation of component A, the amount of PTMG-1800 is adjusted to 379.24 g to prepare a prepolymer containing a halogenated carbamate structure and having an NCO content of 5%.

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

[0134] Example 8

[0135] This embodiment provides a polyurethane composite material, which is basically the same as that of Embodiment 4, except that component A is different. During the preparation of component A, the amount of PTMG-1800 is adjusted to 215.86 g to prepare a prepolymer containing a halogenated carbamate structure and having an NCO content of 10%.

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

[0137] Comparative Example 1

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

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

[0140] Comparative Example 2

[0141] This comparative example provides a polyurethane composition material, which is basically the same as Example 3, except that the component B is different. The component B of this comparative example is 3,3'-dichloro-4,4'-diaminodiphenylmethane.

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

[0143] Comparative Example 3

[0144] This comparative example provides a polyurethane composition, which is basically the same as Example 3, except that, during the preparation of component A, 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 other process conditions are the same as Example 3, to prepare a prepolymer with an NCO content of 8%.

[0145] This comparative example also provides a method for preparing polyurethane from a polyurethane composition, which is basically the same as that of Example 3, except that component A of this comparative example is used instead of component A of Example 3.

[0146] Comparative Example 4

[0147] This comparative example provides a polyurethane composition material, which is basically the same as Example 3, except that component B is different. In the preparation process of component B of this comparative example, the same mass of toluene diisocyanate is used to replace the "first composition" in Example 3, and the amount of 3,3'-dichloro-4,4'-diaminodiphenylmethane is adjusted to 918.88 g, so that toluene diisocyanate and polyol are added according to a molar ratio of NCO to NH2 of 1:6.

[0148] This comparative example also provides a method for preparing polyurethane from a polyurethane composition, which is basically the same as that of Example 3, except that component B of this comparative example is used instead of component B of Example 3.

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

[0150] Table 3 Polyurethane physical property test results

[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] It can be seen from the performance test results in Table 3 that, by using the preparation method of the polyurethane combination material mentioned in the present invention, a polyurethane material with greatly improved tensile strength, elongation at break and flame retardancy can be obtained.

[0153] The performance of Examples 1-4 is better than that of the polyurethane of Comparative Example 1 prepared by using toluene diisocyanate and conventional chain extender ethylene glycol. Compared with Example 3, Comparative Example 2 has a prepolymer component prepared according to the scheme of the present invention, and another component is selected from an unmodified conventional chain extender, and its flame retardant performance is improved by one level, but the improvement of mechanical properties is small. Compared with Example 3, Comparative Example 3 has a prepolymer component modified for pure toluene diisocyanate, and the chain extender component is prepared according to the scheme of the present invention. The degree of improvement of the flame retardant performance of the material 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 invention has played a greater role in improving the flame retardant performance, and the modification of the chain extender component has made a greater contribution to the improvement of the mechanical properties of the material. Under the synergistic effect, a polyurethane material with good mechanical properties and flame retardant properties is obtained.

[0154] Compared with Examples 1-5, Examples 2-4 can further improve the mechanical properties and flame retardant properties of polyurethane by controlling the mass content of halogen-substituted isocyanate or non-halogen-substituted diisocyanate in composition A or composition B within a preferred range. Examples 3-4 can further improve the mechanical properties and flame retardant properties of polyurethane by limiting the NCO content of the prepolymer within a preferred range.

[0155] Compared with Example 6, the mechanical properties and flame retardant properties of the polyurethane prepared in Example 4 by using polytetrahydrofuran polyol with a molecular weight of 400-2000 are further improved.

[0156] Compared with Examples 7 and 8, Example 4 shows that the mechanical properties and flame retardant properties of the polyurethane prepared in Example 4 are further improved by controlling the NCO content of the prepolymer containing a halogenated carbamate structure within a preferred range.

[0157] 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. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A polyurethane composite material, characterized in that: The polyurethane composite material comprises component A and component B; Component A includes a halogen-substituted polyurethane prepolymer; The B component includes a modified polyol chain extender and / or a modified polyamine chain extender substituted with both halogen and urethane.

2. The polyurethane composite material according to claim 1, characterized in that: The raw materials for preparing the halogen-substituted polyurethane prepolymer include a composition containing a halogen-substituted isocyanate and a diisocyanate not substituted by halogen, and a polyol; Preferably, in the composition, the mass content of the halogen-substituted isocyanate is 0.1-35%, more preferably 30-35%; Preferably, in the composition, the mass content of the diisocyanate not substituted by halogen is 65-99.9%, more preferably 65%-70%; Preferably, the polyol is selected from one or more of polyethylene oxide polyol, polypropylene oxide polyol, polytetramethylene glycol, tetramethylene oxide-propylene oxide copolymer glycol, preferably polytetramethylene glycol, more preferably polytetramethylene glycol having a molecular weight of 400-2000.

3. The polyurethane composite material according to claim 1, characterized in that: The raw materials for preparing the modified polyamine chain extender include a composition containing a halogen-substituted isocyanate and a halogen-unsubstituted diisocyanate and a polyamine; Preferably, in the composition, the mass content of the halogen-substituted isocyanate is 0.1-20%, more preferably 15-20%; Preferably, in the composition, the mass content of the diisocyanate not substituted by halogen is 80-99.9%, more preferably 80%-85%; Preferably, the polyamine is selected from one or more of 3,3'-dichloro-4,4'-diaminodiphenylmethane, 2,4-diamino-3,5-dimethylthiotoluene, and melamine, more preferably 2,4-diamino-3,5-dimethylthiotoluene; Preferably, the composition and the polyamine are added in a molar ratio of NCO to NH2 of 1:4-10, and more preferably, the composition and the polyamine are added in a molar ratio of NCO to NH2 of 1:5-6.

4. The polyurethane composite material according to claim 1, characterized in that: The raw materials for preparing the modified polyol chain extender include a composition of a halogen-substituted isocyanate and a halogen-unsubstituted diisocyanate and a polyol; Preferably, in the composition, the mass content of the halogen-substituted isocyanate is 0.1-20%, more preferably 15-20%; Preferably, in the composition, the mass content of the diisocyanate not substituted by halogen is 80-99.9%, more preferably 80%-85%; Preferably, the polyol is selected from one or more of ethylene glycol, 1,4-butanediol, and trimethylolpropane; Preferably, the composition and the polyol are added in a NCO to OH molar ratio of 1:4-10; more preferably, the composition and the polyol are added in a NCO to OH molar ratio of 1:5-6.

5. The polyurethane composition according to any one of claims 2 to 4, 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-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, and 5-chloro-2-methylphenyl isocyanate, preferably one or more of 4-chloro-6-methyl-m-phenyl diisocyanate, 4-bromo-6-methyl-m-phenyl diisocyanate, and 1-bromomethyl-2,4-diisocyanobenzene, and more preferably 4-chloro-6-methyl-m-phenyl diisocyanate.

6. The polyurethane composition according to any one of claims 2 to 5, characterized in that: The diisocyanate not substituted by halogen includes one or more of toluene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, and hexamethylene diisocyanate.

7. The polyurethane composition according to claim 1, characterized in that: The NCO content of the polyurethane prepolymer in component A is 5-10%, preferably 6-8%.

8. The polyurethane composition according to claim 1, characterized in that: The chain extension coefficient of the polyurethane composite material is 0.9 to 0.

95.

9. A polyurethane, characterized in that The raw materials for preparing the polyurethane composite material include any one of claims 1-8.

10. A method for preparing polyurethane from the polyurethane composition according to any one of claims 1 to 8, characterized in that: The method comprises mixing component A and component B, and heating and curing the mixture to obtain a product; Preferably, the mixing is carried out at a temperature of 80-90° C., a rotation speed of 200-400 rpm, a mixing time of 5-15 min, a curing temperature of 100-110° C., and a curing time of 18-30 h.