Phenylene diisocyanate composition as well as preparation method and application thereof

Abstract

The invention relates to a phenyl diisocyanate composition as well as a preparation method and application thereof, the phenyl diisocyanate composition comprises phenyl diisocyanate and 5-7000 ppm of a compound as shown in a formula (1), # imgabs0, and an elastomer prepared from the phenyl diisocyanate composition provided by the invention has excellent anti-fatigue performance.

Description

Technical Field

[0001] The invention relates to the technical field of isocyanates, and in particular to a phenylene diisocyanate composition and a preparation method and application thereof. Background Art

[0002] Phenyl diisocyanate is an aromatic diisocyanate that has long been used as a raw material for polyurethane in various industrial products, especially in high-performance elastomer materials. Phenyl diisocyanate can be obtained by reacting phenylenediamine with phosgene (phosgene).

[0003] Polyurethane microporous elastomer is a microporous foaming material between polyurethane elastomer and polyurethane foam. The outstanding features of microporous elastomer are good elasticity, large deformation, and ability to absorb large impact and vibration energy. Especially in automobiles, polyurethane microporous elastomer can effectively improve vehicle comfort and stability, and can play a role in buffering and shock absorption in various high-speed machinery. At present, NDI is commonly used to prepare microporous elastomers, but the preparation reaction activity of NDI system polyurethane materials is high, and the stirring and pouring time requirements are relatively short. In order to ensure the stability of the product, the process conditions are relatively harsh, which limits the large-scale application of this type of material. P-phenylene diisocyanate has a similar symmetrical structure to NDI, but PPDI has a milder reaction activity and the process is easy to control. The polyurethane microporous elastomer prepared by it has a low compression permanent deformation and excellent tensile strength and load-bearing performance. However, due to the good symmetry of phenylene diisocyanate molecules, the prepared elastomer is more rigid. The fatigue resistance of the elastomer prepared by p-phenylene diisocyanate is lower than that of NDI, and the service life is relatively short.

[0004] Therefore, there is an urgent need in the art to develop a phenylene diisocyanate-based elastomer material with excellent fatigue resistance. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a phenylene diisocyanate composition and a preparation method thereof. The elastomer prepared from the phenylene diisocyanate composition has excellent fatigue resistance.

[0006] The present invention also aims to provide a modified composition of the phenylene diisocyanate composition.

[0007] The present invention also provides a prepolymer, which is formed by reacting the phenylene diisocyanate composition with a substance containing an active hydrogen group, or by reacting the modified composition with a substance containing an active hydrogen group; and an elastomeric material, which includes the prepolymer.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a phenylene diisocyanate composition, comprising phenylene diisocyanate and 5-7000 ppm, preferably 10-3000 ppm, of a compound represented by formula (1);

[0010]

[0011] In detail, the content of the compound represented by formula (1) in the naphthalene diisocyanate composition includes but is not limited to 5 ppm, 10 ppm, 50 ppm, 100 ppm, 500 ppm, 1000 ppm, 1500 ppm, 2000 ppm, 2500 ppm, 3000 ppm, 3500 ppm, 4000 ppm, 4500 ppm, 5000 ppm, 5500 ppm, 6000 ppm, 6500 ppm, 7000 ppm or a range between any two of them.

[0012] The inventors of the present application have found that when the phenylene diisocyanate composition contains 5-7000 ppm by mass of the compound of formula (1), the elastomer prepared therefrom has excellent fatigue resistance. However, when the content of the compound of formula (1) is less than 5 ppm or greater than 7000 ppm, the fatigue resistance will deteriorate.

[0013] In the present invention, hereinafter, the phenylene diisocyanate composition may be referred to as a PPDI composition, phenylene diisocyanate may be referred to as PPDI, and the compound represented by the chemical formula (1) may be referred to as DIN.

[0014] In one embodiment, the phenylene diisocyanate preferably includes any one of 1,2-phenylene diisocyanate, 1,3-phenylene diisocyanate, and 1,4-phenylene diisocyanate, or a combination of at least two thereof, and 1,4-phenylene diisocyanate is preferred.

[0015] In one embodiment, preferably, the compound represented by formula (1) includes but is not limited to any one or a combination of at least two of the following compounds:

[0016]

[0017] In a second aspect, the present invention provides a method for preparing the phenylene diisocyanate composition.

[0018] In the phenylene diisocyanate composition of the present invention, the source of DIN is not limited; DIN can be artificially added to adjust its content, or it can be produced as a by-product in the production of PPDI described later, such as by controlling the content of naphthalene diamine in the raw material phenylenediamine, or by adjusting the DIN content by distillation, etc., to obtain the required content in various feasible ways that can be thought of by skilled technicians.

[0019] In the present invention, the content ratio of DIN in the phenylene diisocyanate composition can be measured by analyzing using a conventional gas chromatography method.

[0020] In one embodiment, the phenylene diisocyanate composition can be obtained by isocyanating the raw material phenylenediamine. The relevant operations and process conditions in the preparation method of the present invention, and the devices used therein, can be carried out by using the corresponding conventional selections in the art, and there is no particular limitation thereto. The technicians can optimize the known processes in the prior art according to actual needs. Specifically, for example, the conditions listed in the following embodiments of the present invention can be used:

[0021] In some specific examples, the raw material phenylenediamine includes any one of 1,2-phenylenediamine, 1,3-phenylenediamine, and 1,4-phenylenediamine, or a combination of at least two thereof.

[0022] In the preparation method of the present invention, as a method for isocyanating phenylenediamine, a phosgenation method can be mentioned, and a method in which phenylenediamine directly reacts with phosgene (also called cold or hot phosgenation method) is preferred. Specifically, the main reaction of the cold photochemical reaction is the formation of carbamoyl chloride and amine hydrochloride, and the main reaction of the hot photochemical reaction is the thermal decomposition from carbamoyl chloride to isocyanate and the phosgenation of amine hydrochloride to isocyanate.

[0023] In practical applications, the reaction method is not particularly limited, and a reactor with internal stirring and a phosgene insertion line is usually used.

[0024] In some specific examples, the cold photochemical reaction process specifically includes: loading a solvent into a reactor, controlling the pressure (gauge pressure) of the reactor to be above 0.01 MPaG and below 1.0 MPaG, preferably below 0.5 MPaG, cooling the temperature to above 0°C and below 130°C, preferably below 90°C, introducing phosgene into the reaction solvent, the molar amount of phosgene introduced is more than 2 times the molar amount of the phenylenediamine, preferably more than 4 times, and the molar amount of phosgene used is less than 20 times the molar amount of the phenylenediamine, preferably less than 10 times, and adding the above-mentioned phenylenediamine dispersed in the solvent. During the reaction, the temperature of the reaction liquid is maintained at a range of above 0°C and below 130°C, preferably below 90°C, and the generated hydrogen chloride is discharged to the outside of the reactor through a reflux condenser, and a compound containing phenylene diisocyanate and the compound shown in formula (1) is obtained at the same time.

[0025] In detail, the pressure (gauge pressure) of the reactor is controlled to include but is not limited to 0.01MPaG, 0.05MPaG, 0.1MPaG, 0.2MPaG, 0.4MPaG, 0.5MPaG, 0.6MPaG, 0.8MPaG, 1.0MPaG or a range between any two thereof; the temperature is cooled to include but is not limited to 0°C, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C , 120°C, 130°C or any range therebetween; the molar amount of phosgene introduced is including but not limited to 2 times, 2.5 times, 3 times, 3.5 times, 4 times or any range therebetween of the molar amount of naphthalene diamine; during the reaction, the temperature of the reaction solution is maintained at including but not limited to 0°C, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C or any range therebetween.

[0026] For example, the solvent may include aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene, chlorinated aromatic hydrocarbons such as monochlorobenzene, o-dichlorobenzene, p-dichlorobenzene, and trichlorobenzene, and chlorinated hydrocarbons such as chloroform and carbon tetrachloride. The aforementioned solvents may be used alone or in combination of two or more. Chlorinated aromatic hydrocarbons are preferred, and chlorobenzene and dichlorobenzene are more preferred.

[0027] Regarding the amount of the solvent, relative to 100 parts by mass of phenylenediamine, the amount of the solvent is more than 400 parts by mass and less than 3000 parts by mass, preferably more than 500 parts by mass and less than 2000 parts by mass, including but not limited to 400 parts by mass, 800 parts by mass, 1200 parts by mass, 1600 parts by mass, 2000 parts by mass, 2400 parts by mass, 2800 parts by mass, 3000 parts by mass or the range composed of any two thereof.

[0028] In some specific examples, the process is based on the aforementioned cold photochemical reaction process, but the reaction condition thermal photochemical reaction specifically includes: in the thermal phosgenation reaction, the pressure (gauge pressure) of the control reactor is controlled to be above 0.01MPaG and the pressure (gauge pressure) is below 1.0MPaG, preferably below 0.5MPaG, and the temperature is raised to a range of above 80°C and below 180°C, and the reaction is continued for more than 30 minutes and less than 8 hours, until the reaction solution is completely clear and transparent, then the reaction is completed. It should be noted that when reacting at a higher temperature, phosgene is gasified and escapes to the outside of the reactor through a reflux condenser, resulting in the loss of phosgene. Therefore, the reaction process needs to be appropriately introduced with phosgene to maintain a certain amount of phosgene reflux. After the thermal phosgenation reaction is completed, nitrogen is introduced into the reactor to remove dissolved phosgene and hydrogen chloride within a range of above 80°C and below 180°C to obtain a reaction solution containing phenyl diisocyanate and a compound shown in formula (1).

[0029] In detail, in the thermal phosgenation reaction, the pressure (gauge pressure) of the reactor is controlled to include but is not limited to 0.01 MPaG, 0.05 MPaG, 0.1 MPaG, 0.2 MPaG, 0.4 MPaG, 0.5 MPaG, 0.6 MPaG, 0.8 MPaG, 1.0 MPaG or a range between any two of them; the heating temperature is increased to include but is not limited to 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, 270°C, 280°C, 290°C, 300°C, 310°C, 320°C, 330°C, 340°C, 350°C, 360°C, 370°C, 380°C, 390°C, 400°C, 410°C, 420°C, 430°C, 440°C, 450°C, 460°C, 470°C, 480°C, 490°C, 500°C, 510°C, 520°C, 530°C, 540°C, 550°C, 560°C, 570°C, 580°C, 590°C, 600°C, 610°C, 610°C, 62 0°C, 180°C or any range therebetween; the reaction time includes but is not limited to 0.5 hour, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours or any range therebetween; after the thermal phosgenation reaction is completed, the temperature for removing the dissolved phosgene and hydrogen chloride includes but is not limited to 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C or any range therebetween.

[0030] In specific implementation, the reaction liquid containing phenylene diisocyanate and the compound represented by formula (1) may be subjected to a desolvation and purification step as necessary, and the solvent may be distilled off from the reaction liquid using a distillation column. Most of the solvent is returned to the isocyanate formation step after purification.

[0031] If necessary, the heavy component tar in the above desolventizing reaction product can also be removed. The heavy component is removed from the reaction solution using equipment such as a short-path evaporator.

[0032] Furthermore, if necessary, the reaction liquid from which the heavy tar has been removed may be purified. The purification method is not particularly limited and may be carried out using industrial separation techniques such as distillation / rectification, crystallization, and the like.

[0033] Generally, when purification is performed by distillation, the distillation tower may be a plate tower or a packed tower. The distillation conditions may be appropriately set according to the DIN content ratio required for the purified phenylene diisocyanate composition. Specifically, the number of theoretical plates of the distillation tower (packed tower) is, for example, 1 or more, preferably 3 or more. Similarly, purification may be performed by using a rectification tower, and the number of theoretical plates of the rectification tower is, for example, 50 or less, preferably 30 or less.

[0034] Preferably, the top pressure of the distillation tower is 0.1 kPa or more, preferably 0.2 kPa or more. The top pressure of the rectification tower is 10 kPa or less, preferably 5 kPa or less.

[0035] Preferably, the top reflux ratio of the distillation tower is 0.05 or more, preferably 1.0 or more. The top reflux ratio of the rectification tower is 40 or less, preferably 25 or less.

[0036] In a preferred embodiment of the present invention, the ratio of DIN can be adjusted to the above range by controlling the reaction conditions and separation conditions. It should be noted that the ratio of DIN in the PPDI composition can also be adjusted by adding DIN to the PPDI composition.

[0037] In a third aspect, the present invention also provides a modified composition of a phenylene diisocyanate composition.

[0038] The modified composition is a modified composition obtained by modifying the phenylene diisocyanate composition, and the structure of the modified composition contains any one or a combination of at least two of the following (a)-(e) groups:

[0039] (a) isocyanurate group, (b) uretdione group, (c) biuret group, (d) carbamate group, (e) urea group, (f) iminooxadiazinedione group, (g) allophanate group, (h) uretonimine group or (i) carbodiimide group.

[0040] A person skilled in the art can modify the aforementioned phenylene diisocyanate composition by a known method as needed to obtain a modified composition of the phenylene diisocyanate composition. The modified composition of the phenylene diisocyanate composition contains a polyisocyanate component and a component containing an active hydrogen group, and can be appropriately utilized as a raw material for a polyurethane resin.

[0041] The source of the groups (a) to (e) in the modified composition is not particularly limited. Specifically, for example, the isocyanurate group is obtained by reacting a naphthalene diisocyanate composition in the presence of a known isocyanurate catalyst to isocyanurate the naphthalene diisocyanate therein.

[0042] The uretdione group can be obtained by heating the naphthalene diisocyanate composition at about 90°C to 200°C, or by reacting it in the presence of a known uretdione catalyst to uretdione the naphthalene diisocyanate (e.g., dimerize it);

[0043] The biuret group can be obtained by reacting a naphthalene diisocyanate composition with water, a tertiary alcohol (e.g., tert-butyl alcohol), a secondary amine (e.g., dimethylamine, diethylamine, etc.), etc., and then further reacting the naphthalene diisocyanate composition in the presence of a known biuret catalyst.

[0044] The carbamate group can be obtained by reacting a naphthalene diisocyanate composition with a polyol component (e.g., trimethylolpropane, etc.);

[0045] The urea group can be obtained by reacting a naphthalene diisocyanate composition with water, a polyamine component (described later), etc.;

[0046] The iminooxadiazinedione group can be obtained by reacting a naphthalene diisocyanate composition in the presence of a known iminooxadiazinedione catalyst to subject the naphthalene diisocyanate to iminooxadiazinedione (e.g., trimerization);

[0047] The allophanate group can be obtained by reacting a naphthalene diisocyanate composition with an alcohol and then further reacting the naphthalene diisocyanate composition with an alcohol in the presence of a known allophanate catalyst.

[0048] The uretonimine group can be obtained by reacting a naphthalene diisocyanate composition in the presence of a known carbodiimide catalyst to form a carbodiimide group, and then adding naphthalene diisocyanate to the carbodiimide group;

[0049] The carbodiimide group can be obtained by reacting a naphthalene diisocyanate composition in the presence of a known carbodiimidization catalyst.

[0050] It should be noted that the modified composition of the phenylene diisocyanate composition may contain at least one of the functional groups (a) to (i) above, and may contain two or more. Such a modified composition may be produced by appropriately combining the above reactions. In addition, the modified composition of the phenylene diisocyanate composition may be used alone or in combination of two or more.

[0051] In a fourth aspect, the present invention further provides a prepolymer, which is formed by reacting the phenylene diisocyanate composition described in the first aspect with a substance containing an active hydrogen group, or by reacting the modified composition described in the second aspect with a substance containing an active hydrogen group.

[0052] The active hydrogen group-containing substance may be selected conventionally in the field. In specific applications, for example, polyol components (components mainly containing polyols having two or more hydroxyl groups), polyamine components (compounds mainly containing polyamines having two or more amino groups), etc. may be cited.

[0053] Examples of the polyol component include low molecular weight polyols and high molecular weight polyols.

[0054] Preferably, the low molecular weight polyol is a compound having two or more hydroxyl groups and a number average molecular weight of 60 or more and less than 500;

[0055] For example, the low molecular weight polyol may be an alkyl glycol having 2 to 12, preferably 2, 4 or 6 carbon atoms, such as ethylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, preferably 1,4-butylene glycol. Dialkylene glycol having 4 to 8 carbon atoms, such as diethylene glycol and dipropylene glycol and / or difunctional to tetrafunctional polyoxyalkylene polyols may also be used. Also usable are trihydric alcohols such as glycerol and trimethylolpropane, tetrahydric alcohols such as tetramethylolmethane (pentaerythritol) and diglycerol, pentahydric alcohols such as xylitol, hexahydric alcohols such as sorbitol, mannitol, allitol, iditol, dulcitol, altritol, inositol and dipentaerythritol, heptahydric alcohols such as avocado, and octahydric alcohols such as sucrose.

[0056] Preferably, the high molecular weight polyol is a compound having a number average molecular weight of 400 or more, for example, 10,000 or less, preferably 5,000 or less, with more than 2 hydroxyl groups. As high molecular weight polyol, for example, polyether polyol, polyester polyol, polycarbonate polyol, polyurethane polyol, epoxy polyol, vegetable oil polyol, polyolefin polyol, acrylic polyol, polysiloxane polyol, fluorine polyol, and vinyl monomer modified polyol can be cited. Specifically, polyester polyol includes, for example, dicarboxylic acid and diol production with 2-12 carbon atoms. Suitable dicarboxylic acids are, for example, aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid and sebacic acid, and aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid. The dicarboxylic acids can be used alone or in a mixture. Regarding the production of polyester polyol, instead of the carboxylic acid, the corresponding derivatives such as carboxylic acid esters, carboxylic anhydrides or acyl chlorides with 1-4 carbon atoms in the alcohol group part can be used optionally and advantageously. The example of diol is diol with 2-16 carbon atoms, preferably 2-6 carbon atoms, such as ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, 102-methylpropane-1,3-diol, 2,2-dimethyl-1,3-propylene glycol, 1,3-propylene glycol and dipropylene glycol. Polyol can be used alone or in combination with two or more. About polyester polyol, preferably use polyethylene adipate, polyadipate 1,4-butylene glycol, polyethylene adipate-butylene glycol, polyadipate 1,6-hexanediol neopentyl glycol, polyadipate 1,6-hexanediol-1,4-butylene glycol, polyadipate 2-methyl-1,3-propylene glycol-1,4-butylene glycol and / or polycaprolactone. Polyoxyalkylene glycols containing suitable ester groups are predominantly polyoxytetramethylene glycols which are polycondensates of organic, preferably aliphatic dicarboxylic acids, especially adipic acid, with polyoxymethylene glycols having a number average molecular weight of 162-600 and optionally aliphatic glycols, especially 1,4-butanediol.

[0057] The above-mentioned polyol components may be used alone or in combination of two or more.

[0058] In addition, in a specific implementation, in the reaction involving the isocyanate component and the component containing the active hydrogen group, when the equivalent ratio of the active hydrogen group to the isocyanate group is less than 1, an isocyanate group-terminated polymer having an isocyanate group at the molecular end is generated, and when the equivalent ratio of the active hydrogen group to the isocyanate group is greater than 1, an active hydrogen group-terminated polymer having an active hydrogen group at the molecular end is generated. Both the isocyanate group-terminated polymer and the active hydrogen group-terminated polymer are contained in the resin (polyurethane resin). The isocyanate group-terminated polymer is a one-component curing resin.

[0059] In a fifth aspect, the present invention further provides an elastomeric material, wherein the elastomeric material comprises the prepolymer described in the fourth aspect.

[0060] Examples of the elastomer material include cast polyurethane elastomer (CPU), thermoplastic polyurethane elastomer (TPU), thermosetting polyurethane elastomer (TSU), and rollable polyurethane elastomer.

[0061] In specific implementation, such an elastomer can be produced, for example, by reacting a polyisocyanate component, a high molecular weight polyol (a component containing an active hydrogen group), and a low molecular weight polyol and / or a low molecular weight polyamine (a component containing an active hydrogen group). That is, the polyisocyanate component, the high molecular weight polyol, the low molecular weight polyol and / or the low molecular weight polyamine are the raw materials of the elastomer.

[0062] Among them, examples of the high molecular weight polyol as a raw material for the elastomer include the above-mentioned polyester polyol (e.g., polycaprolactone polyol, adipic acid-based polyester polyol (polyester polyol using adipic acid as a polybasic acid)), the above-mentioned polycarbonate polyol, and the above-mentioned polytetramethylene ether glycol (e.g., polytetramethylene ether glycol), and preferably the adipic acid-based polyester polyol.

[0063] Among them, examples of the low molecular weight polyol as the raw material of the elastomer include ethylene glycol and 1,4-butanediol, and preferably 1,4-butanediol is used.

[0064] Generally speaking, phenylene diisocyanate-based elastomer materials are usually manufactured by a prepolymer method. Specifically, a prepolymer is obtained by mixing a polyol compound and an isocyanate compound, and a suitable chain extender and a suitable auxiliary agent are optionally added. If necessary, the mixed solution (polymerizable composition) is degassed by an appropriate method and then injected into an injection mold for an elastomer material, which is usually slowly heated from a low temperature to a high temperature to polymerize. Then, the elastomer is demolded to obtain an elastomer.

[0065] In addition, in the method for producing the elastomer, as required, a known urethanization catalyst such as amines, organometallic compounds (e.g., organotin compounds, preferably dibutyltin dichloride, etc.) can be added to the elastomer raw material. Furthermore, as required, conventional additives such as plasticizers, anti-caking agents, heat stabilizers, light stabilizers, ultraviolet absorbers, anti-yellowing agents, antioxidants, mold release agents, pigments, dyes, lubricants, nucleating agents, fillers, anti-hydrolysis agents, etc. can be used in the elastomer in appropriate proportions.

[0066] Additionally, the elastomer can be vulcanized to optimize performance as needed.

[0067] Compared with the prior art, the present invention has the following beneficial effects:

[0068] The phenylene diisocyanate composition provided by the present invention contains 5-7000 ppm of the compound of formula (1), and the elastomer prepared therefrom has excellent anti-fatigue performance. DETAILED DESCRIPTION

[0069] The following examples will further illustrate the method provided by the present invention, but the present invention is not limited to the listed examples, and should also include any other known changes within the scope of the rights claimed by the present invention.

[0070] (I) The determination method of the relevant test in the present invention is as follows:

[0071] 1. Content ratio of the compound DIN represented by formula (1)

[0072] Analysis was performed by gas chromatography under the following conditions using DIN having a purity of 99 mol % as a standard substance by an internal standard method in the examples described later.

[0073] Instrument: Agilent 7890

[0074] (1) Chromatographic column: DB-5 (30m×0.25mm×0.25μm); (2) Injection volume: 0.5μL; (3) Split ratio: 1 / 30; (4) Inlet temperature: 260℃; (5) Column flow rate: 1.5mL / min; (6) Program temperature: 100℃ for 1min, then increase the temperature to 280℃ at 10℃ / min and hold for 20min; (7) FID detector temperature: 280℃; (8) Hydrogen flow rate: 40mL / min, air flow rate: 400mL / min.

[0075] 2. Content ratio of phenylene diisocyanate

[0076] The analysis was performed by gas chromatography under the following conditions using PPDI having a purity of 99 mol % as a standard substance by the internal standard method in the examples described later.

[0077] Instrument: Agilent 7890

[0078] (1) Chromatographic column: DB-5 (30m×0.25mm×0.25μm); (2) Injection volume: 0.5μL; (3) Split ratio: 1 / 30; (4) Inlet temperature: 260℃; (5) Column flow rate: 1.5mL / min; (6) Program temperature: 100℃ for 1min, then increase the temperature to 280℃ at 10℃ / min and hold for 20min; (7) FID detector temperature: 280℃; (8) Hydrogen flow rate: 40mL / min, air flow rate: 400mL / min.

[0079] (II) The sources of the main raw materials used in the present invention are shown in Table 1 below. Other raw materials and reagents were purchased from commercial sources unless otherwise specified:

[0080] Table 1 Raw material information

[0081]

[0082] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0083] It should be noted that, unless otherwise specified, "parts" and "%" are based on mass.

[0084] Preparation Example 1:

[0085] The preparation method of PPDI products is as follows:

[0086] 925 parts by mass of chlorobenzene were charged into the cold photochemical reactor. The temperature in the cold photochemical reactor was adjusted to 60°C, and the pressure (gauge pressure) in the cold photochemical reactor was adjusted to 0.04 MPaG. Phosgene was then introduced into the cold photochemical reactor at a rate of 40 parts by mass / hr. After the condensation reflux of phosgene was established, a mixed solution (amine solution) of 150 parts by mass of PPDA and 800 parts by mass of chlorobenzene was charged into the cold photochemical reactor for 3 hours. Thus, PPDA (1,4-phenylenediamine) cold photochemical liquid was prepared.

[0087] Next, phosgene was continuously introduced into the cold photochemical reactor at a supply rate of 50 parts by mass / hr, and the reaction temperature was raised to 120°C and maintained at this temperature for 3 hours. Thus, the PPDA cold photochemical liquid reacted with phosgene to generate PPDI, thereby preparing a reaction material containing PPDI. In addition, a portion of the unreacted phosgene was condensed into the photochemical reactor by the condenser.

[0088] Next, nitrogen gas was continuously introduced into the reaction solution at a supply rate of 50 parts by mass / hr, and this rate was maintained for 5 hours to remove residual phosgene and hydrogen chloride.

[0089] Next, the photochemical reaction liquid was subjected to a desolvation process at a temperature of 90-120° C. and a pressure of 30 KPaA to prepare 220 parts by weight of a crude product having a PPDI concentration of 90 wt.%.

[0090] After the heavy components were removed from the crude product, the product was separated in a distillation tower, which was filled with a filler equivalent to a theoretical plate number of 5. Then, in the distillation tower, the light components were removed from the top of the tower, and 170 parts by weight of PPDI product were extracted from the tower.

[0091] The distillation conditions in the distillation tower are as follows:

[0092] Tower bottom temperature: 130℃

[0093] Tower top temperature: 110℃

[0094] Tower top pressure: 3kPaA

[0095] Duration: 2-3 hours

[0096] Reflux ratio: 3:1

[0097] Thus, a PPDI product was obtained, in which the DIN content was undetectable.

[0098] Examples 1-5, Comparative Examples 1, 2

[0099] Different amounts of 1,5-DIN (Inokai, purity 99%) were added to the PPDI product obtained in Preparation Example 1 under nitrogen protection to obtain the PPDI compositions of Examples 1-5 and the PPDI compositions of Comparative Examples 1 and 2, as shown in Table 2.

[0100] Example 6

[0101] 4500 ppm of 1,5-diaminonaphthalene was added to 1,4-phenylenediamine as a raw material, and the subsequent operations and parameters were the same as those in Preparation Example 1 to obtain a PPDI composition.

[0102] Example 7

[0103] The PPDI composition of Example 6 was subjected to secondary distillation according to the distillation conditions of Preparation Example 1 to obtain the PPDI composition of Example 7.

[0104] Application performance testing

[0105] The PPDI compositions of the above examples and comparative examples were used to prepare elastomers, and their performance was evaluated as follows:

[0106] (1) Elastomer synthesis

[0107] Prepolymer synthesis: Polytetramethylene ether glycol (PTMEG-1000) was vacuum dehydrated (vacuum degree less than 300 pa) at 130°C for 120 min, then cooled to 70°C, and under N2 protection, PPDI composition was added at one time according to NCO:OH=2:1 (molar ratio), and the prepolymer was obtained by keeping the reaction at 70°C for 120 min, and the NCO% content was analyzed by sampling.

[0108] Preparation of chain extender: Weigh 54.0g BDO, 7.2g deionized water, 0.1g T12, 0.1g 33LV, and 0.2g 3042 foaming agent respectively, mix them evenly at room temperature and set aside.

[0109] Foaming: Weigh a certain amount of prepolymer, and calculate the mass of the required chain extender by the NCO value of the prepolymer according to the formula: m chain extender = m prepolymer × NCO% × 0.95, and the chain extension coefficient (NCO / OH) is 0.95.

[0110] The prepolymer and chain extender were preheated to 70°C, stirred at 1000 r / min for 30 seconds after mixing, and then the sample was quickly poured into a 100°C mold. After the mold was closed, the sample was hot-pressed on a hot press for 30 minutes. The sample was taken out of the mold and then annealed in an oven at 100°C for 24 hours. The sample was then taken out of the oven and stored at room temperature for 7 days before performance characterization.

[0111] (2) Elastomer fatigue resistance test

[0112] A GT-DF-8000 dynamic fatigue testing machine (Taiwan High Speed ​​Rail Testing Instrument Co., Ltd.) was used. The sample was placed between the upper and lower platens of the dynamic fatigue testing machine. The sample was first compressed by 16 mm and then vibrated with an amplitude of 4 mm and a vibration frequency of 4 Hz. The time when the elastomer was damaged was recorded. The results are shown in Table 2.

[0113] Table 2 PPDI composition application effect data

[0114]

[0115] As can be seen from Table 4, the present invention can effectively improve the fatigue resistance of the elastomer prepared from the PPDI composition by controlling the DIN content in the range of 5-7000 ppm. When the DIN content is lower than 5 ppm (Comparative Example 1) and higher than 7000 ppm (Comparative Example 2), the fatigue resistance is inferior to that of the present invention.

[0116] The applicant declares that the present invention illustrates the detailed method of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed method, that is, it does not mean that the present invention must rely on the above-mentioned detailed method to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A phenylene diisocyanate composition, characterized in that: The phenylene diisocyanate composition comprises phenylene diisocyanate and 5-7000 ppm, preferably 10-3000 ppm, of a compound represented by formula (1); 2. The phenylene diisocyanate composition according to claim 1, characterized in that The phenylene diisocyanate is selected from any one of 1,2-phenylene diisocyanate, 1,3-phenylene diisocyanate, and 1,4-phenylene diisocyanate, or a combination of at least two thereof, and 1,4-phenylene diisocyanate is preferred.

3. The phenylene diisocyanate composition according to claim 1 or 2, characterized in that: The compound represented by formula (1) is selected from any one or a combination of at least two of the following compounds:

4. A method for preparing the phenylene diisocyanate composition according to any one of claims 1 to 3, characterized in that: It is prepared by isocyanating the raw material phenylenediamine.

5. The method for preparing the phenylene diisocyanate composition according to claim 4, characterized in that: The phenylenediamine is selected from any one of 1,2-phenylenediamine, 1,3-phenylenediamine and 1,4-phenylenediamine or a combination of at least two thereof.

6. The preparation method according to claim 4 or 5, characterized in that: The isocyanate method is a phosgenation method, preferably a method in which phenylenediamine is directly reacted with phosgene.

7. A modified composition of a phenylene diisocyanate composition, characterized in that: The modified composition is a modified composition obtained by modifying the phenylene diisocyanate composition according to any one of claims 1 to 3; Preferably, the structure of the modified composition contains any one or a combination of at least two of the following (a)-(e) groups: (a) isocyanurate group, (b) uretdione group, (c) biuret group, (d) carbamate group, (e) urea group, (f) iminooxadiazinedione group, (g) allophanate group, (h) uretonimine group or (i) carbodiimide group.

8. A prepolymer, characterized in that The prepolymer is formed by reacting the phenylene diisocyanate composition according to any one of claims 1 to 3 with a substance containing an active hydrogen group, or by reacting the modified composition according to claim 7 with a substance containing an active hydrogen group.

9. An elastomeric material, characterized in that: The elastomeric material comprises the prepolymer of claim 8.

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