Low-temperature-resistant ultrahigh-resilience polyurethane elastomer as well as preparation method and application thereof

Abstract

The invention relates to the technical field of polyurethane elastomers, in particular to a low-temperature-resistant ultrahigh-resilience polyurethane elastomer as well as a preparation method and application thereof. The invention provides a low-temperature-resistant ultrahigh-resilience polyurethane elastomer. The low-temperature-resistant ultrahigh-resilience polyurethane elastomer comprises a component A and a component B, the component A is prepared from the following components in parts by mass: 0 to 100 parts of polyurethane prepolymer and 0.1 to 1 part of antioxidant; on the basis of the mass part of the polyurethane prepolymer, the component B comprises 5-9 parts of a chain extender and 0.1-1 part of a catalyst; the polyurethane prepolymer is prepared from the following raw materials: polytetrahydrofuran diol polyol and isocyanate; the number average molecular weight of the polytetrahydrofuran diol polyol is gt; the invention also relates to a method. The low-temperature-resistant ultrahigh-resilience polyurethane elastomer can meet the requirement that a sealing element product is used in extremely cold areas such as northeast for a long time.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane elastomers, and in particular to a low-temperature resistant ultra-high resilience polyurethane elastomer and a preparation method and application thereof. Background Art

[0002] Polyurethane elastomer is copolymerized by soft segment and hard segment. The soft segment is composed of polyether or polyester polyol, and the hard segment is composed of isocyanate and small molecule chain extender. The type and structure of the soft segment determine the elasticity, low temperature performance and hydrolysis resistance of the material, while the type and structure of the hard segment determine the tear strength, hardness and heat resistance of the material. Due to its excellent wear resistance, elasticity and mechanical strength, wide hardness range, good processing and environmental protection, it is processed into seals and widely used in coal mines, engineering machinery, military industry and chemical industry.

[0003] At present, the rebound of conventional polyurethane elastomer materials on the market is generally between 20% and 60%, and can only be used in an environment of minus 40 degrees. If the temperature is lower than minus 45 degrees, the mechanical properties of the material will drop sharply, the elasticity loss will be great, and even brittle fracture will occur, resulting in oil leakage, and the sealing function will not be able to be played, thus limiting the use of sealing products in extremely cold areas. Therefore, developing a low-temperature resistant, ultra-high rebound polyurethane material is an effective way to solve the above defects and expand the application range of sealing products. Summary of the invention

[0004] The purpose of the present invention is to provide a low temperature resistant ultra-high resilience polyurethane elastomer and its preparation method and application. The low temperature resistant ultra-high resilience polyurethane elastomer can meet the needs of long-term use of sealing products in extremely cold regions such as the Northeast.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a low-temperature resistant ultra-high resilience polyurethane elastomer, comprising component A and component B;

[0007] Calculated by weight, the component A includes 0 to 100 parts of a polyurethane prepolymer and 0.1 to 1 part of an antioxidant;

[0008] Based on the mass fraction of the polyurethane prepolymer, the B component includes 5 to 9 parts of a chain extender and 0.1 to 1 part of a catalyst;

[0009] The raw materials for preparing the polyurethane prepolymer include polytetrahydrofuran diol polyol and isocyanate;

[0010] The number average molecular weight of the polytetrahydrofuran diol polyol is greater than 1000.

[0011] Preferably, the method for preparing the polyurethane prepolymer comprises the following steps:

[0012] Isocyanate is added to polytetrahydrofuran diol polyol, and a prepolymerization reaction is carried out in a protective atmosphere to obtain the polyurethane prepolymer.

[0013] Preferably, the mass ratio of the isocyanate to the polytetrahydrofuran diol polyol is (190-286): (400-600);

[0014] The prepolymerization reaction is carried out under stirring conditions; the stirring temperature is 60-80° C., the rotation speed is 200-400 r / min, and the time is 3 hours.

[0015] Preferably, the polytetrahydrofuran diol polyol includes one or two of conventional polytetrahydrofuran diol, tetrahydrofuran-propylene oxide copolyether diol, tetrahydrofuran-ethylene oxide copolyether diol and side methyl-tetrahydrofuran copolyether diol;

[0016] The isocyanate is diphenylmethane diisocyanate.

[0017] Preferably, the antioxidant includes antioxidant 1010 and / or antioxidant 168.

[0018] Preferably, it also includes a wear-resistant agent;

[0019] Based on the mass fraction of the polyurethane prepolymer, the mass fraction of the anti-wear agent is 0.3 to 2 parts.

[0020] Preferably, the chain extender includes one or two of 1,4-butanediol, hydroquinone dihydroxyethyl ether and ethylene glycol.

[0021] Preferably, the catalyst comprises an organotin catalyst and / or an organobismuth catalyst;

[0022] The mass percentage of tin in the organotin catalyst is 28%;

[0023] The mass percentage of bismuth in the organic bismuth catalyst is 28%.

[0024] The present invention also provides a method for preparing the low-temperature resistant ultra-high resilience polyurethane elastomer described in the above technical solution, comprising the following steps:

[0025] After the polyurethane prepolymer is melted, an antioxidant is added to obtain component A;

[0026] Mixing the chain extender and the catalyst to obtain component B;

[0027] The component A and the component B are mixed and then ripened in a mold to obtain the low-temperature resistant ultra-high resilience polyurethane elastomer.

[0028] The present invention also provides the use of the low-temperature resistant ultra-high resilience polyurethane elastomer described in the above technical solution or the low-temperature resistant ultra-high resilience polyurethane elastomer prepared by the preparation method described in the above technical solution in sealing products.

[0029] The present invention provides a low temperature resistant ultra-high resilience polyurethane elastomer, comprising component A and component B; in terms of mass fraction, the component A comprises 0-100 parts of polyurethane prepolymer and 0.1-1 parts of antioxidant; based on the mass fraction of the polyurethane prepolymer, the component B comprises 5-9 parts of chain extender and 0.1-1 parts of catalyst; the raw materials for preparing the polyurethane prepolymer comprise polytetrahydrofuran diol polyol and isocyanate; the number average molecular weight of the polytetrahydrofuran diol polyol is greater than 1000. The polytetrahydrofuran diol polyol used in the low temperature resistant ultra-high resilience polyurethane elastomer of the present invention has excellent low temperature resistance, which solves the problem that conventional polyurethane elastomer materials (in low temperature environment, the molecular chain gradually loses its softness, changes from a high elastic state to a glassy state, causing the material to lose its original elasticity and strength, the material becomes brittle, and even brittle fracture occurs) cannot be used in a low temperature environment below minus 45°C, and the low temperature resistance and resilience performance of the material are significantly improved. At the same time, the added wear-resistant agent can greatly improve the wear resistance of the material and extend the service life of the polyurethane elastomer. DETAILED DESCRIPTION

[0030] The present invention provides a low-temperature resistant ultra-high resilience polyurethane elastomer, comprising component A and component B;

[0031] Calculated by weight, the component A includes 0 to 100 parts of a polyurethane prepolymer and 0.1 to 1 part of an antioxidant;

[0032] Based on the mass fraction of the polyurethane prepolymer, the B component includes 5 to 9 parts of a chain extender and 0.1 to 1 part of a catalyst;

[0033] The raw materials for preparing the polyurethane prepolymer include polytetrahydrofuran diol polyol and isocyanate;

[0034] The number average molecular weight of the polytetrahydrofuran diol polyol is greater than 1000.

[0035] In the present invention, unless otherwise specified, all preparation raw materials are commercially available products well known to those skilled in the art.

[0036] Calculated by weight, the component A in the low-temperature resistant ultra-high resilience polyurethane elastomer of the present invention includes 0 to 100 parts of polyurethane prepolymer, preferably 10 to 80 parts, and more preferably 30 to 60 parts.

[0037] In the present invention, the preparation method of the polyurethane prepolymer preferably comprises the following steps:

[0038] Isocyanate is added to polytetrahydrofuran diol polyol, and a prepolymerization reaction is carried out in a protective atmosphere to obtain the polyurethane prepolymer.

[0039] In the present invention, the molecular weight of the polytetrahydrofuran diol polyol is greater than 1000, preferably 2000 to 3000. The polytetrahydrofuran diol polyol comprises one or two of conventional polytetrahydrofuran diol, tetrahydrofuran-propylene oxide copolyether diol, tetrahydrofuran-ethylene oxide copolyether diol and side methyl-tetrahydrofuran copolyether diol. When the polytetrahydrofuran diol polyol is two of the above-mentioned specific selections, the present invention has no special restrictions on the ratio of the two substances in the above-mentioned specific selections, and can be mixed in any ratio. In the present invention, the polytetrahydrofuran diol polyol is preferably pretreated, and the pretreatment preferably comprises: melting and dehydrating the polytetrahydrofuran diol polyol in sequence to obtain the molten polytetrahydrofuran diol polyol. In the present invention, the melting temperature is preferably 60-90°C, more preferably 65-85°C, and most preferably 70-80°C; the melting method is preferably water bath heating. In the present invention, the dehydration temperature is preferably 100-120°C, more preferably 105-115°C, and most preferably 108-112°C; the dehydration is preferably carried out under vacuum conditions, and the vacuum degree of the vacuum conditions is preferably -0.097MPa; the dehydration time is preferably 1-2h. After the dehydration is completed, the present invention also preferably includes cooling. The present invention does not have any special limitation on the cooling process, and the process well known to those skilled in the art is adopted to ensure that the temperature is cooled to 40-60°C.

[0040] In the present invention, the isocyanate is preferably diphenylmethane diisocyanate. In the present invention, the isocyanate is preferably pretreated, and the pretreatment preferably includes: melting the isocyanate to obtain the molten isocyanate. In the present invention, the melting temperature is preferably 50 to 70°C, more preferably 55 to 65°C, and most preferably 58 to 62°C. In the present invention, the melting method is preferably water bath heating.

[0041] In the present invention, the mass ratio of the isocyanate to the polytetramethylene glycol polyol is preferably (190-286):(400-600), more preferably (200-260):(450-550), and most preferably (210-230):(480-520).

[0042] In the present invention, the protective atmosphere is preferably a nitrogen atmosphere. In the present invention, the prepolymerization reaction is preferably carried out under stirring, and the stirring speed is preferably 200-400r / min, more preferably 250-350r / min, and most preferably 280-320r / min. In the present invention, the temperature of the prepolymerization reaction is preferably 60-80°C, more preferably 65-75°C, and most preferably 68-72°C; the time of the prepolymerization reaction is preferably 3h.

[0043] After the prepolymerization reaction is completed, the present invention also preferably includes vacuum degassing, and the time of the vacuum degassing is preferably 1 hour; the present invention has no special limitation on other conditions of the vacuum degassing, and the process well known to those skilled in the art can be used.

[0044] In the present invention, the polyurethane prepolymer is preferably a polyurethane prepolymer having an NCO content of 6% to 10%.

[0045] Based on the mass fraction of the polyurethane prepolymer, the component A in the low temperature resistant ultra-high resilience polyurethane elastomer of the present invention includes 0.1 to 1 parts of antioxidant, preferably 0.3 to 0.8 parts, and more preferably 0.4 to 0.6 parts. In the present invention, the antioxidant preferably includes antioxidant 1010 (tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester) and / or antioxidant 168 (tris(2,4-di-tert-butylphenyl) phosphite). When the antioxidant includes antioxidant 1010 and antioxidant 168, the present invention does not have any special restrictions on the ratio of the antioxidant 1010 and antioxidant 168, and can be mixed in any ratio. In a specific embodiment of the present invention, the antioxidant includes antioxidant 1010 and antioxidant 168 in a mass ratio of 1:3.

[0046] In the present invention, the antioxidant is used to prevent the material from oxidative degradation during processing and subsequent use.

[0047] Based on the mass fraction of the polyurethane prepolymer, the component A in the low temperature resistant ultra-high resilience polyurethane elastomer of the present invention also preferably includes 0.3 to 2 parts of anti-wear agent, more preferably 0.5 to 1.5 parts, and most preferably 0.8 to 1.2 parts. In the present invention, the anti-wear agent preferably includes an organosilicon wear agent; the organosilicon wear agent is preferably purchased from Guangzhou Yourun Synthetic Materials Co., Ltd., model CUBD-NML; when the organosilicon wear agent is two or more of the above-mentioned specific selections, the present invention has no special restrictions on the ratio of the above-mentioned specific substances, and can be mixed in any ratio.

[0048] In the present invention, the function of the anti-wear agent is to improve the wear resistance of the material.

[0049] Based on the mass fraction of the polyurethane prepolymer, the low temperature resistant ultra-high resilience polyurethane elastomer of the present invention further includes a B component, and the B component includes 5 to 9 parts of a chain extender, preferably 6 to 8 parts, and more preferably 6.6 to 7.5 parts. In the present invention, the chain extender preferably includes one or two of 1,4-butanediol, hydroquinone dihydroxyethyl ether and ethylene glycol. When the chain extender is two of the above specific options, the present invention has no special restrictions on the ratio of the above specific substances, and can be mixed in any ratio.

[0050] Based on the mass fraction of the polyurethane prepolymer, the B component in the low-temperature resistant ultra-high resilience polyurethane elastomer of the present invention includes 0.1 to 1 parts of catalyst, preferably 0.2 to 0.8 parts, and more preferably 0.4 to 0.6 parts. In the present invention, the catalyst preferably includes an organic tin catalyst and / or an organic bismuth catalyst; the mass percentage of tin in the organic tin catalyst is preferably 28%, and the mass percentage of bismuth in the organic bismuth catalyst is preferably 28%. In the present invention, the organic tin catalyst preferably includes stannous octoate; the organic bismuth catalyst preferably includes bismuth isooctanoate.

[0051] In the present invention, the role of the catalyst is to promote the reaction of the prepolymer and the chain extender and improve the product performance.

[0052] The present invention also provides a method for preparing the low-temperature resistant ultra-high resilience polyurethane elastomer described in the above technical solution, comprising the following steps:

[0053] After the polyurethane prepolymer is melted, an antioxidant is added to obtain component A;

[0054] Mixing the chain extender and the catalyst to obtain component B;

[0055] The component A and the component B are mixed and then ripened in a mold to obtain the low-temperature resistant ultra-high resilience polyurethane elastomer.

[0056] In the present invention, the polyurethane prepolymer is melted and then an antioxidant is added to obtain component A.

[0057] In the present invention, when the component A includes an anti-wear agent, the preparation method of the component A is preferably to melt the polyurethane prepolymer and then add the antioxidant and the anti-wear agent.

[0058] In the present invention, the melting temperature is preferably 60 to 80° C., more preferably 65 to 75° C., most preferably 68 to 72° C.; the melting is preferably carried out in an oven.

[0059] In the present invention, after adding the antioxidant or after adding the antioxidant and the anti-wear agent, stirring is preferably performed, and the present invention has no special limitation on the stirring process, and the stirring process can be performed by a process well known to those skilled in the art. After the stirring is completed, the present invention further preferably includes vacuum degassing, and the vacuum degassing time is preferably 30 to 60 minutes, more preferably 35 to 55 minutes, and most preferably 40 to 50 minutes.

[0060] The preparation method of the present invention also preferably includes mixing a chain extender and a catalyst to obtain a B component.

[0061] In the present invention, the mixing is preferably performed by heating the chain extender and then adding the catalyst. In the present invention, the heating temperature is preferably 60-80°C, more preferably 65-75°C, and most preferably 68-72°C. The present invention does not have any special restrictions on the heating time, and the chain extender can be completely melted by the above-mentioned heating temperature. In the present invention, the heating is preferably performed in an oven. The present invention does not have any special restrictions on the method of adding the catalyst, and it can be added in a manner well known to those skilled in the art.

[0062] After the mixing is completed, the present invention also preferably includes vacuum degassing. The present invention has no special limitation on the process of vacuum degassing, and sufficient degassing can be performed using a process well known to those skilled in the art.

[0063] After obtaining component A and component B, the present invention mixes the component A and component B, and then ripens them in a mold to obtain the low-temperature resistant ultra-high resilience polyurethane elastomer.

[0064] In the present invention, the mixing is preferably carried out under vacuum and stirring conditions. The present invention does not have any special restrictions on the vacuum conditions, and the conditions well known to those skilled in the art can be used. In the present invention, the stirring speed is preferably 1000-1500 r / min, more preferably 1100-1400 r / min, and most preferably 1200-1300 r / min; the stirring time is preferably 1 min.

[0065] In the present invention, the aging process is preferably to pour the mixed mixture into a preheated mold for aging. In the present invention, the preheating temperature of the mold is preferably 110-130°C, more preferably 115-125°C, and most preferably 118-122°C. In the present invention, the aging temperature is preferably 120°C, and the aging time is preferably 16-20h, more preferably 18-19h.

[0066] The present invention also provides the use of the low-temperature resistant ultra-high resilience polyurethane elastomer described in the above technical solution or the low-temperature resistant ultra-high resilience polyurethane elastomer prepared by the preparation method described in the above technical solution in sealing products.

[0067] The low temperature resistant ultra-high resilience polyurethane elastomer provided by the present invention and its preparation method and application are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0068] Example 1

[0069] Preparation of polyurethane prepolymer:

[0070] After the conventional polytetrahydrofuran diol (molecular weight is 2000) of 500g is melted under 70 ℃ water bath condition, put into the reactor, be heated to 120 ℃, dehydrate 1h under the vacuum degree of-0.097MPa, be cooled to 50 ℃, standby;

[0071] Melt diphenylmethane diisocyanate in a water bath at 60°C, cool to 50°C and set aside;

[0072] 238 g of the pretreated diphenylmethane diisocyanate and 500 g of the pretreated conventional polytetrahydrofuran diol were added to a reactor, stirred at 65° C. for 3 h at a speed of 300 r / min under nitrogen, and then vacuum degassed at 80° C. for 30 min to obtain a polyurethane prepolymer having an NCO content of 8.0±0.2%;

[0073] Preparation of component A:

[0074] After heating 500 g of the polyurethane prepolymer to 110° C. to melt, adding 0.5 g of antioxidant 1010 and 1.5 g of antioxidant 168, stirring evenly until completely dissolved, to obtain component A;

[0075] Preparation of component B:

[0076] 42 g of 1,4-butanediol (BDO) and 0.5 g of an organic bismuth catalyst (specifically bismuth isooctanoate, with a bismuth content of 28% by mass) were mixed evenly, heated to 80° C. for vacuum dehydration for 30 min, and cooled to 30° C. to obtain component B;

[0077] Preparation of low temperature resistant and ultra-high resilience polyurethane elastomer material:

[0078] 502 g of the above-mentioned component A at 80°C and 42.5 g of the above-mentioned component B at 30°C are mixed and stirred in a container under vacuum (the stirring speed is 1200 r / min, and the time is 1 min), and the obtained mixture is poured into a tube mold preheated at 120°C, and placed in a 120°C oven for ripening for 20 hours to obtain the low-temperature resistant ultra-high resilience polyurethane elastomer material.

[0079] Example 2

[0080] Preparation of polyurethane prepolymer:

[0081] 500 g of tetrahydrofuran-propylene oxide copolyether glycol (molecular weight 2000) was melted in a water bath at 70° C. and put into a reactor, heated to 120° C., dehydrated at a vacuum degree of -0.097 MPa for 1 h, cooled to 50° C., and set aside;

[0082] Melt diphenylmethane diisocyanate in a water bath at 60°C, cool to 50°C and set aside;

[0083] 238 g of the pretreated diphenylmethane diisocyanate and 500 g of the pretreated tetrahydrofuran-propylene oxide copolyether diol were added to a reactor, stirred at 65° C. for 3 h at a speed of 300 r / min under nitrogen, and then vacuum degassed at 80° C. for 30 min to obtain a polyurethane prepolymer with an NCO content of 8.0±0.2%;

[0084] Preparation of component A:

[0085] After heating and melting 500 g of the polyurethane prepolymer at 110° C., 0.5 g of antioxidant 1010 and 1.5 g of antioxidant 168 were added, and stirred evenly until completely dissolved to obtain component A;

[0086] Preparation of component B:

[0087] 42 g of 1,4-butanediol (BDO) and 0.5 g of an organic bismuth catalyst (specifically bismuth isooctanoate, with a bismuth content of 28% by mass) were mixed evenly, heated to 80° C. for vacuum dehydration for 30 min, and cooled to 30° C. to obtain component B;

[0088] Preparation of low temperature resistant and ultra-high resilience polyurethane elastomer material:

[0089] 502 g of the above-mentioned component A at 80°C and 42.5 g of the above-mentioned component B at 30°C are mixed and stirred in a container under vacuum (the stirring speed is 1200 r / min, and the time is 1 min), and the obtained mixture is poured into a tube mold preheated at 120°C, and placed in a 120°C oven for ripening for 20 hours to obtain the low-temperature resistant ultra-high resilience polyurethane elastomer material.

[0090] Example 3

[0091] Preparation of polyurethane prepolymer:

[0092] 500 g of side methyl-tetrahydrofuran copolyether glycol (molecular weight 2000) was melted in a water bath at 70° C. and put into a reactor, heated to 120° C., dehydrated at a vacuum degree of -0.097 MPa for 1 h, cooled to 50° C., and set aside;

[0093] Melt diphenylmethane diisocyanate in a water bath at 60°C, cool to 50°C and set aside;

[0094] 238 g of the pretreated diphenylmethane diisocyanate and 500 g of the pretreated side methyl-tetrahydrofuran copolyether diol were added to a reactor, stirred at 65° C. for 3 h at a speed of 300 r / min under nitrogen filling, and then vacuum degassed at 80° C. for 30 min to obtain a polyurethane prepolymer with an NCO content of 8.0±0.2%;

[0095] Preparation of component A:

[0096] After heating and melting 500 g of the polyurethane prepolymer at 110° C., 0.5 g of antioxidant 1010 and 1.5 g of antioxidant 168 were added, and stirred evenly until completely dissolved to obtain component A;

[0097] Preparation of component B:

[0098] 42 g of 1,4-butanediol (BDO) and 0.5 g of an organic bismuth catalyst (specifically bismuth isooctanoate with a bismuth content of 28%) were mixed evenly, heated to 80° C. for vacuum dehydration for 30 min, and cooled to 30° C. to obtain component B;

[0099] Preparation of low temperature resistant and ultra-high resilience polyurethane elastomer material:

[0100] 502 g of the above-mentioned component A at 80°C and 42.5 g of the above-mentioned component B at 30°C are mixed and stirred in a container under vacuum (the stirring speed is 1200 r / min, and the time is 1 min), and the obtained mixture is poured into a tube mold preheated at 120°C, and placed in a 120°C oven for ripening for 20 hours to obtain the low-temperature resistant ultra-high resilience polyurethane elastomer material.

[0101] Example 4

[0102] Preparation of polyurethane prepolymer:

[0103] After the conventional polytetrahydrofuran diol (molecular weight is 3000) of 500g is melted under 70 ℃ water bath condition, put into the reactor, be heated to 120 ℃, dehydrate 1h under the vacuum degree of-0.097MPa, be cooled to 50 ℃, standby;

[0104] Melt diphenylmethane diisocyanate in a water bath at 60°C, cool to 50°C and set aside;

[0105] 210.9 g of the pretreated diphenylmethane diisocyanate and 500 g of the pretreated conventional polytetrahydrofuran diol were added to a reactor, stirred at 65° C. for 3 h at a speed of 300 r / min under nitrogen, and then vacuum degassed at 80° C. for 30 min to obtain a polyurethane prepolymer having an NCO content of 8.0±0.2%;

[0106] Preparation of component A:

[0107] After heating and melting 500 g of the polyurethane prepolymer at 110° C., add 0.5 g of antioxidant 1010, 1.5 g of antioxidant 168 and 2.5 g of anti-wear agent (purchased from Guangzhou Yourun Synthetic Materials Co., Ltd., model CUBD-NML), stir evenly until completely dissolved, to obtain component A;

[0108] Preparation of component B:

[0109] 42 g of 1,4-butanediol (BDO) and 0.5 g of an organic bismuth catalyst (specifically bismuth isooctanoate with a bismuth content of 28%) were mixed evenly, heated to 80° C. for vacuum dehydration for 30 min, and cooled to 30° C. to obtain component B;

[0110] Preparation of low temperature resistant and ultra-high resilience polyurethane elastomer material:

[0111] 504.5 g of the above-mentioned component A at 80°C and 42.5 g of the above-mentioned component B at 30°C are mixed and stirred in a container under vacuum (the stirring speed is 1200 r / min, and the time is 1 min), and the obtained mixture is poured into a tube mold preheated at 120°C, and placed in a 120°C oven for ripening for 20 hours to obtain the low-temperature resistant ultra-high resilience polyurethane elastomer material.

[0112] Example 5

[0113] Preparation of polyurethane prepolymer:

[0114] 500 g of tetrahydrofuran-propylene oxide copolyether glycol (molecular weight 3000) was melted in a water bath at 70° C. and put into a reactor, heated to 120° C., dehydrated at a vacuum degree of -0.097 MPa for 1 h, cooled to 50° C., and set aside;

[0115] Melt diphenylmethane diisocyanate in a water bath at 60°C, cool to 50°C and set aside;

[0116] 210.9 g of the pretreated diphenylmethane diisocyanate and 500 g of the pretreated tetrahydrofuran-propylene oxide copolyether diol were added to a reactor, stirred at 65° C. for 3 h at a speed of 300 r / min under nitrogen, and then vacuum degassed at 80° C. for 30 min to obtain a polyurethane prepolymer with an NCO content of 8.0±0.2%;

[0117] Preparation of component A:

[0118] After heating and melting 500 g of the polyurethane prepolymer at 110° C., add 0.5 g of antioxidant 1010, 1.5 g of antioxidant 168 and 2.5 g of anti-wear agent (purchased from Guangzhou Yourun Synthetic Materials Co., Ltd., model CUBD-NML), stir evenly until completely dissolved, to obtain component A;

[0119] Preparation of component B:

[0120] 42 g of 1,4-butanediol (BDO) and 0.5 g of an organic bismuth catalyst (specifically bismuth isooctanoate with a bismuth content of 28%) were mixed evenly, heated to 80° C. for vacuum dehydration for 30 min, and cooled to 30° C. to obtain component B;

[0121] Preparation of low temperature resistant and ultra-high resilience polyurethane elastomer material:

[0122] 504.5 g of the above-mentioned component A at 80°C and 42.5 g of the above-mentioned component B at 30°C are mixed and stirred in a container under vacuum (the stirring speed is 1200 r / min, and the time is 1 min), and the obtained mixture is poured into a tube mold preheated at 120°C, and placed in a 120°C oven for ripening for 20 hours to obtain the low-temperature resistant ultra-high resilience polyurethane elastomer material.

[0123] Example 6

[0124] Preparation of polyurethane prepolymer:

[0125] 500 g of side methyl-tetrahydrofuran copolyether glycol (molecular weight 3000) was melted in a water bath at 70° C. and put into a reactor, heated to 120° C., dehydrated at a vacuum degree of -0.097 MPa for 1 h, cooled to 50° C., and set aside;

[0126] Melt diphenylmethane diisocyanate in a water bath at 60°C, cool to 50°C and set aside;

[0127] 210.9 g of the pretreated diphenylmethane diisocyanate and 500 g of the pretreated side methyl-tetrahydrofuran copolyether diol were added to a reactor, stirred at 65° C. for 3 h at a speed of 300 r / min under nitrogen filling, and then vacuum degassed at 80° C. for 30 min to obtain a polyurethane prepolymer with an NCO content of 8.0±0.2%;

[0128] Preparation of component A:

[0129] After heating and melting 500 g of the polyurethane prepolymer at 110° C., add 0.5 g of antioxidant 1010, 1.5 g of antioxidant 168 and 2.5 g of anti-wear agent (purchased from Guangzhou Yourun Synthetic Materials Co., Ltd., model CUBD-NML), stir evenly until completely dissolved, to obtain component A;

[0130] Preparation of component B:

[0131] 42 g of 1,4-butanediol (BDO) and 0.5 g of an organic bismuth catalyst (specifically bismuth isooctanoate with a bismuth content of 28%) were mixed evenly, heated to 80° C. for vacuum dehydration for 30 min, and cooled to 30° C. to obtain component B;

[0132] Preparation of low temperature resistant and ultra-high resilience polyurethane elastomer material:

[0133] 504.5 g of the above-mentioned component A at 80°C and 42.5 g of the above-mentioned component B at 30°C are mixed and stirred in a container under vacuum (the stirring speed is 1200 r / min, and the time is 1 min), and the obtained mixture is poured into a tube mold preheated at 120°C, and placed in a 120°C oven for ripening for 20 hours to obtain the low-temperature resistant ultra-high resilience polyurethane elastomer material.

[0134] Test Case

[0135] The low temperature resistant ultra-high resilience polyurethane elastomer materials described in Examples 1 to 6 were subjected to performance tests, and the test results are shown in Table 1:

[0136] Table 1 Performance parameters of low temperature resistant ultra-high resilience polyurethane elastomer materials described in Examples 1 to 6

[0137]

[0138] It can be seen from Table 1 that the low-temperature resistant ultra-high resilience polyurethane elastomer material of the present invention has a good low-temperature resistance effect, and tetrahydrofuran-propylene oxide copolyether diol as a soft segment has a more excellent low-temperature resistance. The larger the molecular weight of the polyol, the greater the flexibility, the more complete the microphase separation, the better the low-temperature resistance, and the better the resilience; at the same time, when the wear-resistant agent is added, the low-temperature resistant ultra-high resilience polyurethane elastomer material has a more excellent wear resistance.

[0139] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A low temperature resistant ultra-high resilience polyurethane elastomer, characterized in that: It includes component A and component B; Calculated by weight, the component A includes 0 to 100 parts of a polyurethane prepolymer and 0.1 to 1 part of an antioxidant; Based on the mass fraction of the polyurethane prepolymer, the B component includes 5 to 9 parts of a chain extender and 0.1 to 1 part of a catalyst; The raw materials for preparing the polyurethane prepolymer include polytetrahydrofuran diol polyol and isocyanate; The number average molecular weight of the polytetrahydrofuran diol polyol is greater than 1000.

2. The low temperature resistant ultra-high resilience polyurethane elastomer according to claim 1, characterized in that: The preparation method of the polyurethane prepolymer comprises the following steps: Isocyanate is added to polytetrahydrofuran diol polyol, and a prepolymerization reaction is carried out in a protective atmosphere to obtain the polyurethane prepolymer.

3. The low temperature resistant ultra-high resilience polyurethane elastomer according to claim 2, characterized in that: The mass ratio of the isocyanate to the polytetrahydrofuran diol polyol is (190-286): (400-600); The prepolymerization reaction is carried out under stirring conditions; the stirring temperature is 60-80° C., the rotation speed is 200-400 r / min, and the time is 3 hours.

4. The low temperature resistant ultra-high resilience polyurethane elastomer according to claim 2, characterized in that: The polytetrahydrofuran diol polyol includes one or two of conventional polytetrahydrofuran diol, tetrahydrofuran-propylene oxide copolyether diol, tetrahydrofuran-ethylene oxide copolyether diol and side methyl-tetrahydrofuran copolyether diol; The isocyanate is diphenylmethane diisocyanate.

5. The low temperature resistant ultra-high resilience polyurethane elastomer according to claim 1, characterized in that: The antioxidant includes antioxidant 1010 and / or antioxidant 168 .

6. The low temperature resistant ultra-high resilience polyurethane elastomer according to any one of claims 1 to 5, characterized in that: Also included are anti-wear agents; Based on the mass fraction of the polyurethane prepolymer, the mass fraction of the anti-wear agent is 0.3 to 2 parts.

7. The low temperature resistant ultra-high resilience polyurethane elastomer according to claim 1, characterized in that: The chain extender includes one or two of 1,4-butanediol, hydroquinone dihydroxyethyl ether and ethylene glycol.

8. The low temperature resistant ultra-high resilience polyurethane elastomer according to claim 1, characterized in that: The catalyst includes an organic tin catalyst and / or an organic bismuth catalyst; The mass percentage of tin in the organotin catalyst is 28%; The mass percentage of bismuth in the organic bismuth catalyst is 28%.

9. The method for preparing the low temperature resistant ultra-high resilience polyurethane elastomer according to any one of claims 1 to 8, characterized in that: The following steps are involved: After the polyurethane prepolymer is melted, an antioxidant is added to obtain component A; Mixing the chain extender and the catalyst to obtain component B; The component A and the component B are mixed and then ripened in a mold to obtain the low-temperature resistant ultra-high resilience polyurethane elastomer.

10. Use of the low-temperature resistant ultra-high resilience polyurethane elastomer according to any one of claims 1 to 8 or the low-temperature resistant ultra-high resilience polyurethane elastomer prepared by the preparation method according to claim 9 in sealing products.

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