Low-temperature-resistant and HV-resistant low-temperature hydraulic oil polyurethane elastomer and preparation method thereof

Abstract

The invention discloses a preparation method of polyurethane resistant to-40 DEG C low temperature and HV type low-temperature hydraulic oil, and belongs to the technical field of high polymer materials. Comprising the following steps: enabling a mixture of various polyols and diisocyanate to react for 3-4 hours at the temperature of 80 + / -5 DEG C to obtain a prepolymer; adding a chain extender mixture into the prepolymer, uniformly mixing, carrying out casting molding, and vulcanizing at 100 DEG C for 10-24 hours; and then naturally cooling to room temperature to obtain a low-temperature-resistant HV-resistant low-temperature hydraulic oil polyurethane elastomer sample. According to the invention, by adjusting the ratio of polyester to polyether, the oil resistance and low temperature resistance of the material are balanced to a certain extent, and relatively high strength is maintained. Meanwhile, due to the addition of the low-temperature-resistant plasticizer, the low-temperature-resistant plasticizer wraps the periphery of a molecular chain, friction between the molecular chains is reduced, meanwhile, the molecular chains of the polyurethane elastomer can be smoother, movement of the molecular chains is freer, and the low-temperature-resistant plasticizer can better adapt to low-temperature and oil environments.

Description

[Technical field]

[0001] The invention relates to the technical field of polymer materials, and in particular to a polyurethane elastomer with excellent low temperature resistance and HV type low temperature hydraulic oil resistance and a preparation method thereof. [Background technology]

[0002] Polyurethane elastomers are widely used in defense industry, machinery industry, medical treatment, sports and other fields due to their excellent performance. In some special application scenarios, such as mechanical parts in cold areas, automobile seals and oil pipes, parts of petrochemical equipment, etc., the material is required to have good resistance to HV-type low-temperature hydraulic oil and be able to resist the erosion of oil substances, and to maintain good elasticity and mechanical properties in low-temperature environments. This has promoted the development of low-temperature resistant and HV-type low-temperature hydraulic oil resistant polyurethane elastomer technology. Although improving the low-temperature and oil resistance of polyurethane elastomers has always been a very active topic in the field of polyurethane elastomers, and a lot of research has been conducted, there are still few polyurethane elastomers with excellent comprehensive properties such as low-temperature resistance, HV-type low-temperature hydraulic oil resistance and mechanical properties. Therefore, it is very important to study and improve the low-temperature resistance and HV-type low-temperature hydraulic oil resistance of polyurethane elastomers.

[0003] In the existing polyurethane elastic system, polyether polyurethane elastomer itself has relatively good low temperature performance, but its resistance to HV type low temperature hydraulic oil is poor. Polyester polyurethane generally has good mechanical strength and resistance to HV type low temperature hydraulic oil, but poor low temperature performance. The present invention aims to solve the problem of poor low temperature resistance and resistance to HV type low temperature hydraulic oil of polyurethane elastomer, by providing a polyurethane elastomer that can still maintain good elasticity and physical and mechanical properties in an HV type low temperature hydraulic oil environment at -40°C and a simple, effective and economical preparation method thereof. [Summary of the invention]

[0004] The purpose of the present invention is to provide a polyurethane elastomer with excellent low temperature resistance and HV type low temperature hydraulic oil resistance, so that it can maintain good elasticity, flexibility and mechanical strength in a low temperature environment (-40°C and below), and has good resistance to HV type low temperature hydraulic oil. At the same time, a simple and feasible preparation method is provided to meet the demand for low temperature resistance and HV type low temperature hydraulic oil resistance polyurethane elastomer in the relevant field.

[0005] The present invention is mainly aimed at solving the problem that seals in hydraulic equipment in open air, cold or extremely cold areas (such as Russia or Northeast China), as well as seals in the hydraulic system of low-temperature freezing equipment, need to have good low-temperature flexibility to prevent hardening and brittleness leading to seal failure. There are many low-temperature resistant polyurethanes on the market, and fewer polyurethanes resistant to HV type low-temperature hydraulic oils. There are fewer polyurethane products that have both low-temperature resistance and HV type low-temperature hydraulic oil performance. The present invention has the two advantages of low-temperature resistance and HV type low-temperature hydraulic oil resistance, which meets the working environment of seals in hydraulic equipment in open air, cold or extremely cold areas, and greatly improves the service life of seals.

[0006] The present invention mainly adopts the prepolymer method to prepare the sample, which specifically includes the following contents:

[0007] A method for preparing a polyurethane elastomer with low temperature resistance and HV type low temperature hydraulic oil resistance, the preparation method comprising the following steps: selecting a polyol mixed with polyester and polyether polyols, adding an appropriate amount of phosphoric acid thereto and then dehydrating, adding a certain amount of diisocyanate TDI-100 thereto after complete dehydration, controlling the temperature at 80±5°C to react for 3-4h to obtain a prepolymer; adding a mixed and compounded chain extender to the prepolymer and mixing evenly and then pouring, and after casting and molding, vulcanizing at 100°C for 10-24h; waiting for natural cooling to room temperature to obtain a low temperature resistant and HV type low temperature hydraulic oil resistant polyurethane elastomer sample.

Brief Description of the Drawings

[0008] Figure 1 Process flow chart for preparing low temperature resistant HV type low temperature hydraulic oil polyurethane elastomer [Specific implementation method]

[0009] [Example 1]

[0010] 1. Raw materials preparation:

[0011] Weigh 50 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 25 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer; 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0012] 2. Prepolymer synthesis:

[0013] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0014] 3. Chain extension reaction:

[0015] Take 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0016] 4. Molding and post-processing:

[0017] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0018] 5. Performance testing:

[0019] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0020] [Example 2]

[0021] 1. Raw materials preparation:

[0022] Weigh a certain amount of 50 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 25 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer; 4 parts of E-300, 3 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0023] 2. Prepolymer synthesis:

[0024] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0025] 3. Chain extension reaction:

[0026] Take 4 parts of E-300, 3 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0027] 4. Molding and post-processing:

[0028] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0029] 5. Performance testing:

[0030] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0031] [Example 3]

[0032] 1. Raw materials preparation:

[0033] Weigh a certain amount of 50 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 25 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer; 3 parts of E-300, 4 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0034] 2. Prepolymer synthesis:

[0035] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0036] 3. Chain extension reaction:

[0037] Take 3 parts of E-300, 4 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0038] 4. Molding and post-processing:

[0039] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0040] 5. Performance testing:

[0041] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0042] [Example 4]

[0043] 1. Raw materials preparation:

[0044] Weigh a certain amount of 50 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 25 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer; 2 parts of E-300, 4 parts of TIPA, 4 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0045] 2. Prepolymer synthesis:

[0046] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0047] 3. Chain extension reaction:

[0048] Take 2 parts of E-300, 4 parts of TIPA, 4 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0049] 4. Molding and post-processing:

[0050] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0051] 5. Performance testing:

[0052] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0053] [Example 5]

[0054] 1. Raw materials preparation:

[0055] Weigh a certain amount of 50 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 25 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer; 1 part of E-300, 5 parts of TIPA, 4 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0056] 2. Prepolymer synthesis:

[0057] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0058] 3. Chain extension reaction:

[0059] Take 1 part of E-300, 5 parts of TIPA, 4 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0060] 4. Molding and post-processing:

[0061] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0062] 5. Performance testing:

[0063] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0064] [Comparative Example 1]

[0065] 1. Raw materials preparation:

[0066] Weigh a certain amount of 50 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 50 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100, 12 parts of TXIB plasticizer; 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent, and 0.1 parts of ultraviolet absorber.

[0067] 2. Prepolymer synthesis:

[0068] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0069] 3. Chain extension reaction:

[0070] Take 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0071] 4. Molding and post-processing:

[0072] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0073] 5. Performance testing:

[0074] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0075] [Comparative Example 2]

[0076] 1. Raw materials preparation:

[0077] Weigh a certain amount of 50 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 50 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer; 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0078] 2. Prepolymer synthesis:

[0079] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0080] 3. Chain extension reaction:

[0081] Take 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0082] 4. Molding and post-processing:

[0083] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0084] 5. Performance testing:

[0085] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0086] [Comparative Example 3]

[0087] 1. Raw materials preparation:

[0088] Weigh a certain amount of 25 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 50 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer; 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0089] 2. Prepolymer synthesis:

[0090] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0091] 3. Chain extension reaction:

[0092] Take 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0093] 4. Molding and post-processing:

[0094] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0095] 5. Performance testing:

[0096] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0097] [Comparative Example 4]

[0098] 1. Raw materials preparation:

[0099] Weigh a certain amount of 25 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 50 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 25 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer; 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0100] 2. Prepolymer synthesis:

[0101] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0102] 3. Chain extension reaction:

[0103] Take 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0104] 4. Molding and post-processing:

[0105] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0106] 5. Performance testing:

[0107] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0108] [Comparative Example 5]

[0109] 1. Raw materials preparation:

[0110] Weigh a certain amount of 25 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 50 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 6 parts of TXIB plasticizer; 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0111] 2. Prepolymer synthesis:

[0112] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0113] 3. Chain extension reaction:

[0114] Take 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0115] 4. Molding and post-processing:

[0116] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0117] 5. Performance testing:

[0118] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0119] [Comparative Example 6]

[0120] 1. Raw materials preparation:

[0121] Weigh a certain amount of 25 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 50 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 18 parts of TXIB plasticizer; 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0122] 2. Prepolymer synthesis:

[0123] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0124] 3. Chain extension reaction:

[0125] Take 5 parts of E-300, 2 parts of TIPA, 3 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of UV absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0126] 4. Molding and post-processing:

[0127] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0128] 5. Performance testing:

[0129] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0130] [Comparative Example 7]

[0131] 1. Raw materials preparation:

[0132] Weigh a certain amount of 50 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 25 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer; 5 parts of E-300, 5 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0133] 2. Prepolymer synthesis:

[0134] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0135] 3. Chain extension reaction:

[0136] Take 5 parts of E-300, 5 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0137] 4. Molding and post-processing:

[0138] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0139] 5. Performance testing:

[0140] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0141] [Comparative Example 8]

[0142] 1. Raw materials preparation:

[0143] Weigh a certain amount of 50 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 25 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer; 5 parts of E-300, 5 parts of TIPA, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber.

[0144] 2. Prepolymer synthesis:

[0145] Mix the polyols, and add a certain amount of phosphoric acid to the polyols according to the calculation results; dehydrate the polyols at a temperature range of 100-120°C, and the dehydration time is not less than 2 hours; cool the polyols after dehydration to a temperature range of 50-80°C; add the materials according to the calculation results, first add the polyols, and then add TDI-100; heat to 80°C and react for 3.5 hours; determine the NCO content, degas within the temperature range of 80±5°C after the reaction, and bottle and seal for storage.

[0146] 3. Chain extension reaction:

[0147] Take 5 parts of E-300, 5 parts of PEG, 10 parts of TXIB, 0.1 parts of antioxidant, 0.1 parts of anti-hydrolysis agent and 0.1 parts of ultraviolet absorber as chain extenders, mix and stir evenly; heat the prepolymer to about 80°C, add the chain extender in proportion, stir evenly and pour into a mold at 115°C for compression molding; take out the sample after compression molding.

[0148] 4. Molding and post-processing:

[0149] The sample was vulcanized at 100° C. for 16 hours and naturally cooled to room temperature to obtain a polyurethane elastomer sample.

[0150] 5. Performance testing:

[0151] The prepared samples were tested for physical properties at room temperature, and the samples were immersed in HV type low-temperature hydraulic oil at -40°C, and the hardness, tensile strength, tear strength, rebound change, mass swelling rate, etc. of the samples were tested. The test methods were carried out in accordance with national standards GB / T 529-2008, GB / T 528-2009, GB / T 1689-2014, and GB / T 1682-2014.

[0152] [Comparative Example 9]

[0153] Commercially available Zibo Hengjiu Polyurethane HJ7235 products

[0154] Results Test

[0155] 1. Tensile, tear, hardness and rebound tests

[0156] Example 1

[0157]

[0158]

[0159] Example 2

[0160]

[0161] Example 3

[0162]

[0163] Example 4

[0164]

[0165] Example 5

[0166]

[0167]

[0168] Comparative Example 1

[0169]

[0170] When the prepolymer lacks polytetrahydrofuran polyol with a molecular weight of 2000, the low temperature resistance is greatly reduced.

[0171] Comparative Example 2

[0172]

[0173] When the prepolymer lacks polycaprolactone polyol with a molecular weight of 2000, the low temperature resistance is not greatly affected.

[0174] Comparative Example 3

[0175]

[0176] When the prepolymer contains 25 parts of polytetramethylene glycol polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 50 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer, the low temperature resistance is reduced.

[0177] Comparative Example 4

[0178]

[0179] When the prepolymer contains 25 parts of polytetramethylene glycol polyol with a molecular weight of 2000, 50 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 25 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer, the low temperature resistance decreases.

[0180] Comparative Example 5

[0181]

[0182] When the prepolymer contains 25 parts of polytetramethylene glycol polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 50 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 6 parts of TXIB plasticizer, the low temperature resistance decreases.

[0183] Comparative Example 6

[0184]

[0185]

[0186] When the prepolymer contains 25 parts of polytetramethylene glycol polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 50 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 18 parts of TXIB plasticizer, the low temperature resistance is reduced.

[0187] Comparative Example 7

[0188]

[0189] When the chain extender contains 5 parts of E-300, 5 parts of PEG, and 10 parts of TXIB, the low temperature resistance decreases.

[0190] Comparative Example 8

[0191]

[0192] When the chain extender contains 5 parts of E-300, 5 parts of TIPA, and 10 parts of TXIB, the low temperature resistance decreases.

[0193] Comparative Example 9

[0194]

[0195] The commercially available Zibo Hengjiu Polyurethane HJ7235 product has significantly lower low-temperature resistance.

[0196] 2. -40℃ HV hydraulic oil immersion swelling test

[0197]

[0198] Comparative Example 1: When the prepolymer lacks polytetramethylene glycol with a molecular weight of 2000, the performance of resistance to HV type low-temperature hydraulic oil is reduced.

[0199] Comparative Example 2: When the prepolymer lacks polycaprolactone polyol with a molecular weight of 2000, the performance of HV type low-temperature hydraulic oil resistance is greatly reduced.

[0200] Comparative Example 3: When the prepolymer contains 25 parts of polytetramethylene glycol polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 50 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer, the performance of HV type low-temperature hydraulic oil resistance is reduced.

[0201] Comparative Example 4: When the prepolymer contains 25 parts of polytetramethylene glycol polyol with a molecular weight of 2000, 50 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 25 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 12 parts of TXIB plasticizer, the performance of HV type low-temperature hydraulic oil resistance is reduced.

[0202] Comparative Example 5: When the prepolymer contains 25 parts of polytetrahydrofuran polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 50 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 6 parts of TXIB plasticizer, the performance of HV type low-temperature hydraulic oil resistance is reduced.

[0203] Comparative Example 6: When the prepolymer contains 25 parts of polytetramethylene glycol polyol with a molecular weight of 2000, 25 parts of ethylene glycol-butanediol-adipic acid polyester polyol with a molecular weight of 2000, 50 parts of polycaprolactone polyol with a molecular weight of 2000, 19 parts of TDI-100 and 18 parts of TXIB plasticizer, the performance of HV type low-temperature hydraulic oil resistance is reduced.

[0204] Comparative Example 7: When the chain extender contains 5 parts of E-300, 5 parts of PEG, and 10 parts of TXIB, the performance of the HV type low-temperature resistant hydraulic oil is reduced.

[0205] Comparative Example 8: When the chain extender contains 5 parts of E-300, 5 parts of TIPA, and 10 parts of TXIB, the performance of the HV type low-temperature resistant hydraulic oil is reduced.

[0206] Comparative Example 9: The commercially available Zibo Hengjiu polyurethane HJ7235 product has significantly lower resistance to HV type low-temperature hydraulic oil.

[0207] Beneficial Effects

[0208] When the prepolymer lacks 2000 molecular weight polytetrahydrofuran polyol, the low temperature resistance of the polyurethane sample is greatly reduced; when the prepolymer lacks 2000 molecular weight polycaprolactone polyol, the HV type low temperature hydraulic oil resistance of the polyurethane sample is greatly reduced. When TIPA is lacking in the chain extender, the low temperature resistance and HV type low temperature hydraulic oil resistance of the polyurethane sample are both reduced; when PEG is lacking in the chain extender, the low temperature resistance and HV type low temperature hydraulic oil resistance of the polyurethane sample are both reduced. When the experimental formula of the present invention is used, the low temperature resistance and HV type low temperature hydraulic oil resistance of the polyurethane elastomer are greatly improved.

[0209] When the polyurethane elastomer material prepared by the present invention is exposed to a low-temperature hydraulic oil environment at -40°C, its tensile strength decreases, while the tear strength, resilience and hardness do not change much. And the polyurethane elastomer can still maintain good flexibility and processability, effectively solving the problem of low-temperature embrittlement of existing polyurethane elastomers. In addition, after being immersed in HV type low-temperature hydraulic oil at -40°C for a long time, the swelling rate of the material remains below 5%, which is much lower than the existing mature products on the market. Moreover, the preparation process adopted is relatively simple, easy to operate and control, and is conducive to large-scale industrial production. By optimizing the ratio of raw materials, it can ensure that the production cost is reasonably controlled under the premise of low-temperature resistance and improve the market competitiveness of the product.

[0210] Comprehensive test results show that the polyurethane elastomer prepared by the present invention shows more superior low temperature resistance and resistance to HV type low temperature hydraulic oil than other products on the market.

Claims

1. A low temperature resistant HV type low temperature hydraulic oil resistant polyurethane elastomer, characterized in that: The method comprises the following steps: a certain amount of polytetrahydrofuran polyol, ethylene glycol-butanediol-adipic acid, polycaprolactone polyol, diisocyanate and plasticizer are used as raw materials of prepolymer, the mixture is uniformly mixed and then reacted with diisocyanate at a certain temperature to form prepolymer; E-300, TIPA, PEG, TXIB, antioxidant, anti-hydrolysis agent and ultraviolet absorber are compounded and prepared as chain extender; the prepolymer and the chain extender are subjected to chain extension reaction and poured, and then vulcanized at a certain temperature for a period of time to form polyurethane elastomer.

2. The low temperature resistant HV type low temperature hydraulic oil resistant polyurethane elastomer according to claim 1, characterized in that: The molecular weight of the polytetrahydrofuran polyol, the polyester polyol of ethylene glycol-butanediol-adipic acid and the polycaprolactone polyol is 2000, and the weight parts thereof are 50 parts, 25 parts and 25 parts respectively.

3. The low temperature resistant HV type low temperature hydraulic oil resistant polyurethane elastomer according to claim 1, characterized in that: The diisocyanate is TDI-100 with an NCO content of 48.3%, and its mass fraction is 19 parts.

4. The low temperature resistant HV type low temperature hydraulic oil resistant polyurethane elastomer according to claim 1, characterized in that: The plasticizer has a density of 0.86 kg / m at 20°C. 3 The mass fraction of TXIB is 12 parts.

5. The low temperature resistant HV type low temperature hydraulic oil resistant polyurethane elastomer according to claim 1, characterized in that: The chain extender is a composite preparation of E-300, TIPA, PEG-200, TXIB, an antioxidant, an anti-hydrolysis agent, and an ultraviolet absorber, and the weight proportions thereof are 1-5 parts of E-300, 1-5 parts of TIPA, 1-5 parts of PEG-200, 5-10 parts of TXIB, 0.1-0.5 parts of antioxidant, 0.1-0.5 parts of anti-hydrolysis agent, and 0.1-0.5 parts of ultraviolet absorber, respectively.

6. The low temperature resistant HV type low temperature hydraulic oil resistant polyurethane elastomer according to claim 1, characterized in that: The synthesis reaction temperature of the prepolymer is 80±5°C, and the reaction time is 3-4h; the chain extension reaction temperature is 80°C, and the chain extension time is 10-30min; the vulcanization temperature is 100°C, and the vulcanization time is 10-24h.

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