Raw material composition for preparing thermoplastic polyurethane and thermoplastic polyurethane elastomer

Abstract

The invention provides a raw material composition for preparing thermoplastic polyurethane and a thermoplastic polyurethane elastomer, the raw material composition of thermoplastic polyurethane comprises polymer polyol, a chain extender and aliphatic diisocyanate, the molecular structure of the aliphatic diisocyanate contains a six-membered saturated aliphatic ring, and the molecular structure of the aliphatic diisocyanate contains a six-membered saturated aliphatic ring. The chain extender comprises a compound with a structure as shown in a formula 1 and / or a formula 2: # imgabs0 # imgabs1 #, a and b are respectively and independently natural numbers greater than or equal to 1 and are not 1 at the same time, and c, d and e are respectively and independently natural numbers greater than or equal to 1. According to the raw material composition, the prepared thermoplastic polyurethane has relatively high heat resistance on the premise of having excellent yellowing resistance.

Description

Technical Field

[0001] The invention relates to the field of thermoplastic polyurethane elastomers, in particular to a raw material composition for preparing thermoplastic polyurethane and a thermoplastic polyurethane elastomer. Background Art

[0002] The yellowing resistance of polyurethane (PU) materials refers to their ability to resist yellowing or discoloration under the influence of light, heat, oxygen and other environmental factors. This property is very important for many applications, especially those products that need to be exposed to sunlight for a long time (such as outdoor coatings, textiles, automotive interiors, etc.).

[0003] Compared with aromatic thermoplastic polyurethanes, aliphatic thermoplastic polyurethanes are widely used outdoors or in environments with strong ultraviolet radiation due to their good yellowing resistance. However, due to their raw material structure, the heat resistance of the overall material is usually much lower than that of aromatic thermoplastic polyurethanes. The specific value is manifested in a lower Vicat softening point, which seriously limits their application in high temperature environments.

[0004] The prior art improves the heat resistance of aliphatic thermoplastic polyurethane by introducing diamine chain extenders into the raw materials of aliphatic thermoplastic polyurethane, but the introduction of diamine chain extenders will reduce the yellowing resistance of the material. Therefore, how to make aliphatic thermoplastic polyurethane have both yellowing resistance and heat resistance is an urgent problem to be solved in the field of polyurethane materials. Summary of the invention

[0005] In view of the above problems, the present invention provides a raw material composition for preparing thermoplastic polyurethane. The raw material composition uses a chain extender with a special structure and is used in combination with an aliphatic diisocyanate having the same structural unit, so that the prepared thermoplastic polyurethane has excellent yellowing resistance and high heat resistance.

[0006] The present invention also provides a thermoplastic polyurethane elastomer, which is prepared from raw materials including the raw material composition. Therefore, the thermoplastic polyurethane elastomer has good yellowing resistance and high temperature resistance.

[0007] The present invention also provides a method for preparing a thermoplastic polyurethane elastomer. Since the method comprises the step of using the raw material composition, the thermoplastic polyurethane elastomer with a higher Vicat softening point and better yellowing resistance can be prepared.

[0008] In a first aspect, the present invention provides a raw material composition for preparing thermoplastic polyurethane, comprising: a polymer polyol, a chain extender and an aliphatic diisocyanate, wherein the molecular structure of the aliphatic diisocyanate contains a six-membered saturated aliphatic ring; the chain extender comprises a compound having a structure as shown in Formula 1 and / or Formula 2:

[0009]

[0010] Wherein, a and b are each independently a natural number greater than or equal to 1, and a and b are not 1 at the same time, and c, d, and e are each independently a natural number greater than or equal to 1.

[0011] Furthermore, the chain extender also satisfies the following conditions: 1≤a≤4;

[0012] and / or, 1≤b≤4;

[0013] and / or, 1≤c≤4;

[0014] and / or, 1≤d≤4;

[0015] And / or, 1≤e≤4.

[0016] Furthermore, the diisocyanate containing a six-membered saturated aliphatic ring includes one or more of dicyclohexylmethane-4,4'-diisocyanate, 1,4-cyclohexyl dimethylene diisocyanate, and 1,4-cyclohexane diisocyanate.

[0017] Further, the polymer polyol includes one or more of polyester polyol, polyether polyol, polycaprolactone polyol and polycarbonate polyol;

[0018] Preferably, the polyether polyol comprises polytetramethylene glycol and / or polyethylene glycol-propylene glycol; the polyester polyol comprises polybutylene adipate diol and / or polyhexane adipate diol;

[0019] Preferably, the number average molecular weight of the polymer polyol is 500 to 4000 g / mol, more preferably 1000 to 2500 g / mol.

[0020] Furthermore, the ratio of the equivalent of the aliphatic diisocyanate to the total equivalent of the hydroxyl groups in the polymer polyol and the chain extender is 0.8 to 1.2, preferably 0.95 to 1.05.

[0021] Furthermore, the raw material composition further comprises a catalyst and / or an auxiliary agent; wherein the catalyst comprises one or more of a tertiary amine catalyst, an organic tin catalyst, an organic bismuth catalyst, and an organic zinc catalyst;

[0022] And / or, the auxiliary agent includes one or more of a light stabilizer, an antioxidant, and a hydrolysis stabilizer.

[0023] Furthermore, based on the total mass of the aliphatic diisocyanate, the polymer polyol and the chain extender, the amount of the catalyst added is 1-200 ppm.

[0024] And / or, the additive is added in an amount of 2-5 wt %.

[0025] Furthermore, based on the total mass of the raw material composition, the proportion of the chain extender is 2-35%, preferably 5-25%.

[0026] And / or, the polymer polyol accounts for 15-70%, preferably 40-60%,

[0027] And / or, the aliphatic diisocyanate accounts for 15-60%, preferably 20-40%.

[0028] In a second aspect, the present invention provides a thermoplastic polyurethane elastomer prepared from raw materials including the raw material composition described in the first aspect.

[0029] In a third aspect, the present invention provides a method for preparing a thermoplastic polyurethane elastomer, comprising the following steps: reacting and molding a material comprising the raw material composition described in the first aspect.

[0030] The raw material composition for preparing thermoplastic polyurethane provided by the present invention can ensure that the prepared thermoplastic polyurethane has excellent yellowing resistance and high heat resistance by using a chain extender with a special structure and using aliphatic diisocyanate with the same structural unit.

[0031] Furthermore, the thermoplastic polyurethane elastomer provided by the present invention has a high Vicat softening point and excellent yellowing resistance. DETAILED DESCRIPTION

[0032] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below. The specific implementation methods listed below are only for describing the principles and features of the present invention. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0033] In this application, the term "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0034] In this application, the term "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b or c", or "at least one of a, b and c" can all mean: a, b, c, ab (i.e. a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0035] In this application, references to "one embodiment", "an example", or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment, embodiment, or example is included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment", "an embodiment", "an example", or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any appropriate combination and / or subcombination.

[0036] In a first aspect, the present invention provides a raw material composition for preparing thermoplastic polyurethane, comprising: a polymer polyol, a chain extender and an aliphatic diisocyanate, wherein the molecular structure of the aliphatic diisocyanate contains a six-membered saturated aliphatic ring; the chain extender comprises a compound having a structure as shown in Formula 1 and / or Formula 2:

[0037]

[0038] Wherein, a and b are each independently a natural number greater than or equal to 1, and a and b are not 1 at the same time, and c, d, and e are each independently a natural number greater than or equal to 1.

[0039] In the present invention, by introducing a chain extender having a structure as shown in Formula 1 and / or Formula 2 into the raw material composition for preparing thermoplastic polyurethane, and limiting the molecular structure of aliphatic diisocyanate to contain a six-membered saturated aliphatic ring, not only the heat resistance of thermoplastic polyurethane can be improved, but also the yellowing resistance of thermoplastic polyurethane can be ensured. The main reasons include: since the above chain extender includes compounds having a structure as shown in Formula 1 and / or Formula 2, these compounds and aliphatic isocyanate structures both include a six-membered saturated aliphatic ring, which can improve the regularity of molecular arrangement in the hard segment of thermoplastic polyurethane and increase the hard segment density, and this is more regular and has greater steric hindrance. The hard segment structure helps to prevent it from being incorporated into the soft segment phase region, thereby improving the overall microphase separation degree of the material to improve the heat resistance of the thermoplastic polyurethane material, and the improvement of thermal stability also helps to reduce the possibility of thermal oxidative degradation, which also helps to improve the yellowing resistance of the thermoplastic polyurethane. In addition, the chain extender includes compounds with structures shown in Formula 1 and / or Formula 2. These compounds have greater steric hindrance than traditional short-chain chain extenders (for example: 1,4-butanediol), which will protect the thermoplastic polyurethane chain from direct attack by ultraviolet rays to a certain extent, reduce the possibility of photodegradation, and further improve the yellowing resistance of the thermoplastic polyurethane.

[0040] In an optional embodiment, the chain extender further satisfies the following conditions: 1≤a≤4;

[0041] and / or, 1≤b≤4;

[0042] and / or, 1≤c≤4;

[0043] and / or, 1≤d≤4;

[0044] And / or, 1≤e≤4.

[0045] The chain extender as described above can not only improve the yellowing resistance and heat resistance of thermoplastic polyurethane, but also ensure the reactivity of the chain extender with aliphatic diisocyanate, making the reaction more complete and the reaction rate moderate, thereby ensuring the molecular weight and crosslinking density of the thermoplastic polyurethane material.

[0046] In an alternative embodiment, the diisocyanate containing a six-membered saturated aliphatic ring includes one or more of dicyclohexylmethane-4,4'-diisocyanate, 1,4-cyclohexyl dimethylene diisocyanate, and 1,4-cyclohexane diisocyanate.

[0047] The diisocyanate as described above can provide better weather resistance and UV resistance, making the thermoplastic polyurethane more suitable for outdoor applications, and the diisocyanate can better cooperate with the chain extender to improve the regularity of the molecular arrangement in the hard segment of the thermoplastic polyurethane, thereby further improving the overall microphase separation degree of the thermoplastic polyurethane material, thereby further improving the heat resistance of the thermoplastic polyurethane material.

[0048] In an alternative embodiment, the polymer polyol includes one or more of polyester polyol, polyether polyol, polycaprolactone polyol and polycarbonate polyol.

[0049] As for the specific selection of polymer polyols, it can be determined according to the application of thermoplastic polyurethane and the required performance characteristics. Among them, thermoplastic polyurethane prepared from polyester polyols usually has excellent wear resistance and mechanical strength, and has good tolerance to grease, solvents and some chemicals, and is suitable for application scenarios requiring high wear resistance and mechanical strength; thermoplastic polyurethane prepared from polyether polyols usually has better low-temperature flexibility and elasticity, good hydrolysis stability, and is suitable for use in humid environments; polycaprolactone polyols have good biocompatibility and are suitable for medical and biological applications; polycarbonate polyols have excellent heat resistance and chemical resistance, and the prepared thermoplastic polyurethanes are suitable for use in harsh environments.

[0050] In addition, the polymer polyols described above can be purchased directly or prepared according to conventional methods, for example, by catalytic ring-opening and ring-closing reactions.

[0051] In order to further improve the low-temperature flexibility and elasticity of thermoplastic polyurethane, in an optional embodiment, the polyether polyol includes polytetramethylene glycol and / or polyethylene glycol-propylene glycol diol; in order to further improve the wear resistance and mechanical strength of thermoplastic polyurethane, the polyester polyol includes polybutylene adipate diol and / or polyhexane adipate diol.

[0052] In an alternative embodiment, the average functionality of the polymer polyol is 1.8 to 3.0, preferably 2.0.

[0053] Among them, the average functionality of the polymer polyol is the average number of hydroxyl groups in the polymer polyol molecular chain. Generally, the specific value of the average functionality of the polymer polyol can be determined according to the application scenario and performance requirements of the thermoplastic polyurethane. For example, when the average functionality of the polymer polyol is any integer greater than or equal to 1.8 and less than or equal to 2, it helps to form a thermoplastic polyurethane with excellent flexibility and elasticity. When the average functionality of the polymer polyol is any integer greater than 2 and less than or equal to 3, it helps to form a thermoplastic polyurethane with higher mechanical strength.

[0054] Polymer polyols with higher number average molecular weights usually result in longer polymer chains, which help to improve the elasticity, flexibility and thermal stability of thermoplastic polyurethane elastomers. Polymer polyols with lower number average molecular weights usually improve the fluidity of the material, making it easier to process and mold. In order to make the thermoplastic polyurethane elastomer have higher elasticity, flexibility, thermal stability and easy processability; in an optional embodiment, the number average molecular weight of the polymer polyol is 500-4000 g / mol, more preferably 1000-2500 g / mol.

[0055] Exemplarily, the number average molecular weight of the polymer polyol is 1000 g / mol, 1100 g / mol, 1200 g / mol, 1300 g / mol, 1400 g / mol, 1500 g / mol, 1600 g / mol, 1700 g / mol, 1800 g / mol, 1900 g / mol, 2000 g / mol, 2100 g / mol, 2200 g / mol, 2300 g / mol, 2400 g / mol, 2500 g / mol, etc., any value or a range consisting of any two of the values.

[0056] In an optional embodiment, the ratio of the equivalent weight of the aliphatic diisocyanate to the total equivalent weight of the hydroxyl groups in the polymer polyol and the chain extender is 0.8 to 1.2, preferably 0.95 to 1.05.

[0057] The ratio of the equivalent weight of the above aliphatic diisocyanate to the total equivalent weight of the hydroxyl groups in the polymer polyol and the chain extender can also be referred to as -NCO / -OH. When -NCO / -OH is within the range of the above implementation mode, the isocyanate group and the hydroxyl group are basically completely reacted, which helps to form a highly heat-resistant thermoplastic polyurethane with high elasticity and good flexibility.

[0058] In an optional embodiment, the raw material composition further comprises a catalyst and / or an auxiliary agent; wherein the catalyst comprises one or more of a tertiary amine catalyst, an organic tin catalyst, an organic bismuth catalyst, and an organic zinc catalyst;

[0059] And / or, the auxiliary agent includes one or more of a light stabilizer, an antioxidant, and a hydrolysis stabilizer.

[0060] The catalyst as described above can accelerate the reaction of isocyanate with polyol or water, control the reaction time and curing speed, and thus adjust the mechanical properties of the thermoplastic polyurethane material; the light stabilizers as described above, such as UV absorbers and light stabilizers, are used to improve the light resistance of the thermoplastic polyurethane material and prevent degradation and discoloration caused by ultraviolet rays; the antioxidants as described above, such as phenolic and amine antioxidants, are used to prevent oxidative degradation of polyurethane during processing and use; the hydrolysis stabilizers as described above, such as at least one of carbodiimide compounds, epoxy compounds, organosilicon compounds, imide compounds, etc., react with the active groups in the thermoplastic polyurethane to form a more stable chemical structure, thereby reducing the possibility of hydrolysis of the thermoplastic polyurethane.

[0061] In a specific embodiment, the organotin catalyst includes one or more of stannous octoate, dibutyltin dilaurate, and dibutyltin dioctoate.

[0062] In an optional embodiment, based on the total mass of the aliphatic diisocyanate, the polymer polyol and the chain extender, the added amount of the catalyst is 1-200 ppm;

[0063] And / or, the additive is added in an amount of 2-5 wt %.

[0064] The catalyst added in the above amount can ensure uniform reaction and relatively fast reaction rate, thereby ensuring the mechanical properties of thermoplastic polyurethane, while the additive added in the above amount can improve the corresponding properties of thermoplastic polyurethane without affecting the flexibility and elasticity of thermoplastic polyurethane.

[0065] Exemplarily, the amount of the catalyst added is any value among 1ppm, 10ppm, 20ppm, 30ppm, 40ppm, 50ppm, 60ppm, 70ppm, 80ppm, 90ppm, 100ppm, 110ppm, 120ppm, 130ppm, 140ppm, 150ppm, 160ppm, 170ppm, 180ppm, 190ppm, etc., or a range consisting of any two of them; the amount of the auxiliary agent added is any value among 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, 4.5wt%, 5wt%, etc., or a range consisting of any two of them.

[0066] Generally speaking, changing the amount of chain extender can adjust the length of the polyurethane molecular chain and the cross-linking density, thereby adjusting the hardness, elasticity and chemical resistance of the thermoplastic polyurethane. Since the chain extender of the present invention includes the compound represented by Formula 1 and / or Formula 2, therefore, changing the amount of chain extender of the present invention can further ensure the heat resistance and yellowing resistance of the thermoplastic polyurethane. In an optional embodiment, based on the total mass of the raw material composition, the proportion of the chain extender is 2-35%, preferably 5-25%.

[0067] The content of polyols will affect the flexibility, hardness and thermal stability of polyurethane. In order to further ensure the flexibility, hardness and thermal stability of thermoplastic polyurethane, in an optional embodiment, based on the total mass of the raw material composition, the proportion of the polymer polyol is 15-70%, preferably 40-60%.

[0068] Aliphatic diisocyanates provide thermoplastic polyurethanes with excellent UV resistance to reduce yellowing, making thermoplastic polyurethanes suitable for outdoor applications. In addition, the hard segment formed by the reaction of aliphatic diisocyanates and chain extenders is also an important factor in determining the weather resistance, transparency, hardness and other properties of thermoplastic polyurethanes. Therefore, in order to further balance the relationship between the UV resistance, transparency, hardness and other properties of thermoplastic polyurethanes, in an optional embodiment, the proportion of the aliphatic diisocyanate is 15-60%, preferably 20-40%.

[0069] In a second aspect, the present invention provides a thermoplastic polyurethane elastomer prepared from raw materials including the raw material composition described in the first aspect.

[0070] In a third aspect, the present invention provides a method for preparing a thermoplastic polyurethane elastomer, comprising the following steps: reacting materials comprising the raw material composition described in the first aspect to obtain the thermoplastic polyurethane elastomer.

[0071] In some embodiments, the method for preparing a thermoplastic polyurethane elastomer specifically comprises the following steps:

[0072] Aliphatic diisocyanate, polymer polyol, chain extender, optional catalyst and optional auxiliary agent are mixed and extruded through an extruder to obtain the thermoplastic polyurethane elastomer; wherein the temperature of the extruder is 120-240°C.

[0073] The preparation method can control the temperature of the extruder to make the raw material composition react in the extruder in a one-step polymerization process, thereby obtaining the thermoplastic polyurethane elastomer.

[0074] In some embodiments, the method further comprises the steps of cooling, crushing and granulating after extrusion.

[0075] In order to further understand the present invention, the technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than 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.

[0076] The novel alicyclic diols involved in the embodiments, such as 1,1-bis(4-hydroxymethylcyclohexyl)methane, 1,2-bis(4-hydroxymethylcyclohexane)ethane, etc., can be prepared with reference to patent US3467719A, and the brief preparation method is as follows: A general method for obtaining novel diols is to reduce the corresponding biphenyl carboxylic acid or bis(carboxyphenyl) alkane or ester in two steps, first reducing the aromatic (benzene nucleus) to the alicyclic (cyclohexane) nucleus, and then reducing the carboxyl group to a hydroxymethyl group. The reduction of the benzene ring can be conveniently achieved by hydrogenating the acid ester under the catalysis of platinum oxide or ruthenium; and the carboxylic acid group of the alicyclic acid obtained by reduction is easily obtained by hydrogenation using a catalyst such as copper chromate or by reaction with lithium aluminum hydride.

[0077] Unless otherwise specified, the reagents involved in the embodiments of the present invention are all commercially available products and can be purchased through commercial channels. Among them, some raw materials are shown in Table 1;

[0078] Table 1:

[0079] name purity factory 1,4-Cyclohexyl dimethylene diisocyanate Industrial Grade Wanhua Chemical Group Co., Ltd. 1,4-cyclohexane diisocyanate Industrial Grade Wanhua Chemical Group Co., Ltd. Dicyclohexylmethane-4,4'-diisocyanate Industrial Grade Wanhua Chemical Group Co., Ltd. Polycarbonate diol Industrial Grade Wanhua Chemical Group Co., Ltd. 1,4-Cyclohexanedimethanol Industrial Grade Green Union (Jining) Chemical Technology Co., Ltd. 1,4-cyclohexanediethanol Industrial Grade Chongqing Futeng Pharmaceutical Co., Ltd. Antioxidant 1010 Industrial Grade Tianjin Lianlong New Materials Co., Ltd. Carbodiimide Industrial Grade Shenzhen Zhongke New Material Technology Co., Ltd.

[0080] Example 1

[0081] This example provides a raw material composition for preparing a thermoplastic polyurethane elastomer and a thermoplastic polyurethane elastomer, wherein the raw material composition comprises the following components:

[0082] 26.2 parts of 1,4-cyclohexyl dimethylene diisocyanate;

[0083] 55.0 parts of polycarbonate diol;

[0084] 1,4-cyclohexanediethanol 18.8 parts, its structural formula is:

[0085]

[0086] Stannous octoate 100ppm;

[0087] Antioxidant 10101.5 parts;

[0088] Anti-hydrolysis agent: 0.5 parts of carbodiimide;

[0089] Wherein, the number average molecular weight of the polycarbonate diol is 2000 g / mol;

[0090] The preparation method of the thermoplastic polyurethane elastomer comprises the following steps:

[0091] (1) adding the raw material composition into a heated extruder, wherein the temperature of each temperature zone of the extruder is set to 140-220° C., to form a thermoplastic polyurethane elastomer;

[0092] (2) Cooling the thermoplastic polyurethane elastomer, crushing and granulating.

[0093] Example 2

[0094] This example provides a raw material composition for preparing a thermoplastic polyurethane elastomer and a thermoplastic polyurethane elastomer, wherein the raw material composition comprises the following components:

[0095] 1,4-cyclohexane diisocyanate 24.3 parts;

[0096] 55.0 parts of polycarbonate diol;

[0097] 20.7 parts of 1,4-cyclohexanediethanol, the structural formula of which is:

[0098]

[0099] Stannous octoate 120ppm;

[0100] 1.5 parts of antioxidant 1010;

[0101] Anti-hydrolysis agent: 0.5 parts of carbodiimide;

[0102] Wherein, the number average molecular weight of polycarbonate diol is 2000 g / mol;

[0103] The preparation method of the above thermoplastic polyurethane elastomer is the same as that of Example 1.

[0104] Example 3

[0105] This example provides a raw material composition for preparing a thermoplastic polyurethane elastomer and a thermoplastic polyurethane elastomer, wherein the raw material composition comprises the following components:

[0106] 29.9 parts of dicyclohexylmethane-4,4'-diisocyanate;

[0107] 55.0 parts of polycarbonate diol;

[0108] 15.1 parts of 1,4-cyclohexanediethanol, the structural formula of which is:

[0109]

[0110] Dibutyltin dilaurate 80ppm;

[0111] 1.5 parts of antioxidant 1010;

[0112] 0.5 part of hydrolysis-resistant agent carbodiimide;

[0113] Wherein, the number average molecular weight of polycarbonate diol is 2000 g / mol;

[0114] The preparation method of the above thermoplastic polyurethane elastomer is the same as that of Example 1.

[0115] Example 4

[0116] This example provides a raw material composition for preparing a thermoplastic polyurethane elastomer and a thermoplastic polyurethane elastomer, wherein the raw material composition comprises the following components:

[0117] 26.8 parts of dicyclohexylmethane-4,4'-diisocyanate;

[0118] 55.0 parts of polycarbonate diol;

[0119] 1,1-bis(4-hydroxymethylcyclohexyl)methane 18.2 parts, the structural formula of which is:

[0120]

[0121] Dibutyltin dilaurate 80ppm;

[0122] 1.5 parts of antioxidant 1010;

[0123] Anti-hydrolysis agent: 0.5 parts of carbodiimide;

[0124] Wherein, the number average molecular weight of polycarbonate diol is 2000 g / mol;

[0125] The preparation method of the thermoplastic polyurethane elastomer is the same as that in Example 1.

[0126] Example 5

[0127] This example provides a raw material composition for preparing a thermoplastic polyurethane elastomer and a thermoplastic polyurethane elastomer, wherein the raw material composition comprises the following components:

[0128] 26.8 parts of dicyclohexylmethane-4,4'-diisocyanate; 55.0 parts of polytetramethylene ether glycol;

[0129] 1,1-bis(4-hydroxymethylcyclohexyl)methane 18.2 parts, the structural formula of which is:

[0130]

[0131] Dibutyltin dilaurate 80ppm;

[0132] 1.5 parts of antioxidant 1010;

[0133] Anti-hydrolysis agent: 0.5 parts of carbodiimide;

[0134] Wherein, the number average molecular weight of polycarbonate diol is 2000 g / mol;

[0135] The preparation method of the thermoplastic polyurethane elastomer is the same as that in Example 1.

[0136] Example 6

[0137] This example provides a raw material composition for preparing a thermoplastic polyurethane elastomer and a thermoplastic polyurethane elastomer, wherein the raw material composition comprises the following components:

[0138] 26.3 parts of dicyclohexylmethane-4,4'-diisocyanate;

[0139] 55.0 parts of polycarbonate diol;

[0140] 1,2-bis(4-hydroxymethylcyclohexyl)ethane 18.7 parts, the structural formula of which is:

[0141]

[0142] Dibutyltin dilaurate 80ppm;

[0143] 1.5 parts of antioxidant 1010;

[0144] 0.5 part of hydrolysis-resistant agent carbodiimide;

[0145] Wherein, the number average molecular weight of polycarbonate diol is 2000 g / mol;

[0146] The preparation method of the thermoplastic polyurethane elastomer is the same as that in Example 1.

[0147] Example 7

[0148] This example provides a raw material composition for preparing a thermoplastic polyurethane elastomer and a thermoplastic polyurethane elastomer, wherein the raw material composition comprises the following components:

[0149] 26.3 parts of dicyclohexylmethane-4,4'-diisocyanate;

[0150] 55.0 parts of polycarbonate diol;

[0151] 1,2-bis(4-hydroxymethylcyclohexyl)ethane 18.7 parts, the structural formula of which is:

[0152]

[0153] Stannous octoate 140ppm;

[0154] 3.5 parts of antioxidant 1010;

[0155] 1 part of hydrolysis-resistant agent carbodiimide;

[0156] Wherein, the number average molecular weight of polycarbonate diol is 2000 g / mol;

[0157] The preparation method of the thermoplastic polyurethane elastomer is the same as that in Example 1.

[0158] Example 8

[0159] This example provides a raw material composition for preparing a thermoplastic polyurethane elastomer and a thermoplastic polyurethane elastomer, wherein the raw material composition comprises the following components:

[0160] 24.1 parts of dicyclohexylmethane-4,4'-diisocyanate;

[0161] 60.0 parts of polycarbonate diol;

[0162] 15.9 parts of 1,2-bis(4-hydroxymethylcyclohexyl)ethane, the structural formula of which is:

[0163]

[0164] Bismuth 2-ethylhexanoate 180ppm;

[0165] 3.5 parts of antioxidant 1010;

[0166] 1 part of hydrolysis-resistant agent carbodiimide;

[0167] Wherein, the number average molecular weight of polycarbonate diol is 2000 g / mol;

[0168] The preparation method of the thermoplastic polyurethane elastomer is the same as that in Example 1.

[0169] Comparative Example 1

[0170] This example provides a raw material composition for preparing a thermoplastic polyurethane elastomer and a thermoplastic polyurethane elastomer, wherein the raw material composition comprises the following components:

[0171] 35.2 parts of dicyclohexylmethane-4,4'-diisocyanate;

[0172] 55.0 parts of polycarbonate diol;

[0173] 1,4-Butanediol 9.8 parts;

[0174] Dibutyltin dilaurate 80ppm;

[0175] 1.5 parts of antioxidant 1010;

[0176] 0.5 part of hydrolysis-resistant agent carbodiimide;

[0177] Wherein, the number average molecular weight of polycarbonate diol is 2000 g / mol;

[0178] The preparation method of the thermoplastic polyurethane elastomer is the same as that in Example 1.

[0179] Comparative Example 2

[0180] This example provides a raw material composition for preparing a thermoplastic polyurethane elastomer and a thermoplastic polyurethane elastomer, wherein the raw material composition comprises the following components:

[0181] 31.5 parts of dicyclohexylmethane-4,4'-diisocyanate;

[0182] 55.0 parts of polycarbonate diol;

[0183] 1,4-cyclohexanedimethanol 13.5 parts, its structural formula is:

[0184]

[0185] Dibutyltin dilaurate 80ppm;

[0186] 1.5 parts of antioxidant 1010;

[0187] 0.5 part of hydrolysis-resistant agent carbodiimide;

[0188] Wherein, the number average molecular weight of polycarbonate diol is 2000 g / mol;

[0189] The preparation method of the thermoplastic polyurethane elastomer is the same as that in Example 1.

[0190] The thermoplastic polyurethane elastomers prepared in the above examples and comparative examples were subjected to performance tests.

[0191] Yellowing resistance grade: The thermoplastic polyurethane elastomers prepared in the above embodiments and comparative examples were injection molded by using an injection molding machine at a processing temperature range of 180-220°C to make 2 mm injection molded test pieces. The test method was based on method B in HG / T3689-2014 standard. The test pieces were placed under a UVA lamp with a wavelength of 370 nm and an ultraviolet intensity of 25 ± 0.4 W / m 2 , so that the vertical distance from the UVA lamp is 250±2mm, the ambient temperature is maintained at 45℃, the test is carried out for 30 days, and the yellowing resistance grade is determined using a HUNTERLABULTURESCAN PRO colorimeter;

[0192] Vicat softening point: 3 mm thick Vicat softening point standard specimens were prepared by injection molding in the processing temperature range of 180-220°C using an injection molding machine. The HV6M hot deformation Vicat tester produced by INSTRON was used to test the 3.0 mm sample prepared by the injection molding process.

[0193] The test results are shown in Table 2:

[0194] Table 2:

[0195] serial number Yellowing resistance grade Vicat softening point / ℃ Example 1 5 67 Example 2 5 79 Example 3 5 72 Example 4 5 95 Example 5 5 80 Example 6 5 76 Example 7 5 83 Example 8 5 69 Comparative Example 1 4.5 50 Comparative Example 2 4.5 53

[0196] It can be seen from Table 2 that, compared with Comparative Examples 1-2, the thermoplastic polyurethane elastomer prepared in the embodiment has better yellowing resistance and heat resistance, and therefore, it can be used as an extruded film material and an injection molded sheet material in various fields.

[0197] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A raw material composition for preparing thermoplastic polyurethane, characterized in that: include: A polymer polyol, a chain extender and an aliphatic diisocyanate, wherein the molecular structure of the aliphatic diisocyanate contains a six-membered saturated aliphatic ring; and the chain extender includes a compound having a structure as shown in Formula 1 and / or Formula 2: Wherein, a and b are each independently a natural number greater than or equal to 1, and a and b are not 1 at the same time, and c, d, and e are each independently a natural number greater than or equal to 1.

2. The raw material composition according to claim 1, characterized in that The chain extender also satisfies the following conditions: 1≤a≤4; and / or, 1≤b≤4; and / or, 1≤c≤4; and / or, 1≤d≤4; And / or, 1≤e≤4.

3. The raw material composition according to claim 1, characterized in that The diisocyanate containing a six-membered saturated aliphatic ring includes one or more of dicyclohexylmethane-4,4'-diisocyanate, 1,4-cyclohexyl dimethylene diisocyanate, and 1,4-cyclohexane diisocyanate.

4. The raw material composition according to claim 1, characterized in that The polymer polyol includes one or more of polyester polyol, polyether polyol, polycaprolactone polyol and polycarbonate polyol; Preferably, the polyether polyol comprises polytetramethylene glycol and / or polyethylene glycol-propylene glycol; the polyester polyol comprises polybutylene adipate diol and / or polyhexane adipate diol; Preferably, the number average molecular weight of the polymer polyol is 500 to 4000 g / mol, more preferably 1000 to 2500 g / mol.

5. The raw material composition according to claim 1, characterized in that The ratio of the equivalent of the aliphatic diisocyanate to the total equivalent of the hydroxyl groups in the polymer polyol and the chain extender is 0.8 to 1.2, preferably 0.95 to 1.

05.

6. The raw material composition according to claim 1, characterized in that The raw material composition further includes a catalyst and / or an auxiliary agent; wherein the catalyst includes one or more of a tertiary amine catalyst, an organic tin catalyst, an organic bismuth catalyst, and an organic zinc catalyst; And / or, the auxiliary agent includes one or more of a light stabilizer, an antioxidant, and a hydrolysis stabilizer.

7. The raw material composition according to claim 6, characterized in that Based on the total mass of the aliphatic diisocyanate, polymer polyol and chain extender, the added amount of the catalyst is 1-200 ppm. And / or, the additive is added in an amount of 2-5 wt %.

8. The raw material composition according to any one of claims 1 to 7, characterized in that: Based on the total mass of the raw material composition, the chain extender accounts for 2-35%, preferably 5-25%. And / or, the polymer polyol accounts for 15-70%, preferably 40-60%, And / or, the aliphatic diisocyanate accounts for 15-60%, preferably 20-40%.

9. A thermoplastic polyurethane elastomer, characterized in that: The method is prepared from raw materials comprising the raw material composition described in any one of claims 1 to 8.

10. A method for preparing a thermoplastic polyurethane elastomer, characterized in that: The following steps are involved: The material comprising the raw material composition according to any one of claims 1 to 8 is reacted to obtain the thermoplastic polyurethane elastomer.

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