Polarity-resistant organic solvent polyurethane elastomer and preparation method thereof

Abstract

The invention relates to a polarity-resistant organic solvent polyurethane elastomer and a preparation method thereof, and belongs to the field of preparation of organic polymer materials. The polyurethane elastomer is prepared from mixed polyol, mixed isocyanate, a mixed curing agent and a plasticizer, the prepared polyurethane elastomer is soaked in acetone or cyclohexanone for 1, 3, 7 and 14 days, the weight increase rate is smaller than 35%, the shore hardness is kept at about 40A, the polyurethane elastomer can be used for a long time in a polar organic solvent environment, and the service life of the polyurethane elastomer is prolonged. And good polar organic solvent resistance is maintained.

Description

[Technical field]

[0001] The invention relates to a polyurethane elastomer, in particular to a polyurethane elastomer with excellent resistance to polar organic solvents and a preparation method thereof, belonging to the technical field of polymer materials. [Background technology]

[0002] Polyurethane is an organic polymer material, which is polymerized from isocyanate and hydroxyl compounds. The main chain contains a repeated carbamate structure. The carbamate group has strong polarity and good toughness, wear resistance, aging resistance and chemical corrosion resistance. It is widely used in the printing and coating industries. The resistance of ordinary polyurethane elastomers to polar organic solvents is often insufficient, and it is prone to swelling and degradation, resulting in reduced performance and shortened service life. At present, there are still some problems with polar organic solvent-resistant polyurethane elastomers, such as complex processes, high costs, and limited performance improvements.

[0003] In "Synthesis and Structural Characterization of Chemical-Resistant Polyurethane Elastomers", Jiang Zhifa used polyester 218 and TDI-100 as the main raw materials, synthesized polyurethane elastomers by the prepolymer method, and discussed the influence of different chain extender ratios on the chemical resistance of polyurethane elastomers. After the products were immersed in cyclohexanone, ethyl acetate, tetrahydrofuran and toluene for 120 hours, the swelling rates of the polyurethane elastomers were 150%, 100%, 175% and 43%. The elastomer prepared by this formula has a lower swelling rate in toluene, but a higher swelling rate in cyclohexanone, ethyl acetate and tetrahydrofuran. Long-term immersion will greatly reduce the performance of the product.

[0004] In "Preparation of Solvent-Resistant Polyester Polyols and Their Application in Low-Hardness Elastomers", Yang Pingping introduced succinic acid into the polyester polyol system to improve the solvent resistance of the polyester polyol, and adopted a one-step method to prepare a low-hardness polyurethane elastomer. The polyurethane elastomer synthesized with polyester polyols with a relative molecular mass of about 4000 had a swelling rate of about 42% after immersion in cyclohexanone for 48 hours. However, polyols with a larger relative molecular mass have a larger viscosity, making industrial operation more difficult.

[0005] The purpose of the present invention is to solve the deficiencies in the prior art and provide a polyurethane elastomer with better resistance to polar organic solvents. The synthesized polyurethane elastomer has the advantages of low preparation cost, simple and convenient processing, easy automation and continuous production compared with the products currently sold on the market. It has excellent mechanical properties and will not crack after long-term immersion in polar organic solvents, and can be well applied to the printing industry. [Summary of the invention]

[0006] The purpose of the present invention is to provide a polar organic solvent resistant polyurethane elastomer and a preparation method thereof, so as to overcome the deficiencies in the prior art, so that the obtained polyurethane elastomer has excellent polar organic solvent resistance while maintaining good mechanical properties and processing properties, and the preparation process is simple and the cost is low.

[0007] In order to synthesize an excellent polar organic solvent-resistant polyurethane elastomer, the technical solution adopted by the present invention is as follows:

[0008] The polar organic solvent resistant polyurethane elastomer is synthesized by a prepolymer method. The prepolymer is prepared by reacting polyol with isocyanate, and the prepared prepolymer is reacted with a curing agent to obtain the polar organic solvent resistant polyurethane elastomer.

[0009] The present invention synthesizes a polar organic solvent-resistant polyurethane elastomer, and the weight composition of the prepolymer component and the curing agent is as follows:

[0010] Prepolymer ingredients

[0011]

[0012]

[0013] Curing agent ingredients

[0014]

[0015] In the present invention, the anti-hydrolysis agent is selected from one or more of STABAXOL I, UN-025, and S-7000.

[0016] In the present invention, the ultraviolet absorber is selected from one or more of o-hydroxybenzophenone, o-hydroxybenzotriazole and salicylic acid ester.

[0017] In the present invention, the catalyst is selected from one or more of T-9, DABCO-T-12 and TEA.

[0018] In the present invention, the solvent used in the immersion experiment of the polar organic solvent-resistant polyurethane elastomer is a polar organic reagent.

[0019] In the present invention, the polar organic reagent is acetone or cyclohexanone, and the weight portion is 110-150 parts.

[0020] The polar organic solvent resistant polyurethane elastomer obtained by the invention has a weight increase rate of less than 35% after being immersed in cyclohexanone for 1, 3, 7 and 14 days, and its Shore hardness is maintained at about 40A. The polyurethane elastomer is mainly used in printing and decoration industries.

[0021] The swelling rate test method of the present invention is carried out in accordance with the national standard GB / T 1690-2010, and the hardness test is carried out in accordance with the national standard GB / T531.1-2008. [Specific implementation method]

[0022] [Example 1]

[0023] Step 1: Mix 80 parts of polyethylene succinate, 20 parts of carbonate polyol, and 15 parts of cyclohexane oil, and then heat to 100° C. in a vacuum environment and dehydrate for 30 minutes to obtain a mixed polyol.

[0024] After dehydration, the room temperature is cooled to below 60°C, liquefied MDI, 5 parts, and MDI-100, 23 parts, are added to the mixed polyols, heated and stirred at 85°C for 5 hours, and samples are taken to determine NCO, and degassing is completed. The prepolymer synthesis is completed.

[0025] Step 2: Prepolymer and curing agent trimethylolpropane (TMP), 5 parts; triisopropanolamine (TIPA), 5 parts; 1,4-butanediol (BDO), 5 parts; 988SG, 10 parts; DMN500, 5 parts; antioxidant, 0.3 parts; anti-hydrolysis agent, 0.3 parts; ultraviolet absorber, 0.3 parts; catalyst, 0.08 parts are quickly stirred at 85°C, with a weight ratio of 100:8.52, poured into a mold, vacuum degassed and placed in an oven at 115°C for 24 hours for vulcanization molding, and the synthesis of the polar organic solvent-resistant polyurethane elastomer is completed.

[0026] [Example 2]

[0027] Step 1: 80 parts of polyethylene succinate, 20 parts of polycarbonate polyol, and 20 parts of cyclohexane oil are mixed, and then heated to 100° C. in a vacuum environment and dehydrated for 30 minutes to obtain a mixed polyol.

[0028] After dehydration, the room temperature is cooled to below 60°C, liquefied MDI (part 6) and MDI-100 (part 24) are added to the mixed polyols, heated and stirred at 85°C for 5 hours, samples are taken to determine NCO, and degassing is performed. The prepolymer synthesis is completed.

[0029] Step 2: Prepolymer and curing agent trimethylolpropane (TMP), 5 parts; triisopropanolamine (TIPA), 5 parts; 1,4-butanediol (BDO), 5 parts; 988SG, 10 parts; DMN500, 5 parts; antioxidant, 0.3 parts; anti-hydrolysis agent, 0.3 parts; ultraviolet absorber, 0.3 parts; catalyst, 0.08 parts are quickly stirred at 85°C, with a weight ratio of 100:8.42, poured into a mold after vacuum degassing, and placed in an oven at 115°C for 24 hours for vulcanization molding, and the synthesis of the polar organic solvent-resistant polyurethane elastomer is completed.

[0030] [Example 3]

[0031] Step 1: Mix 80 parts of polyethylene succinate, 20 parts of polycarbonate polyol, and 25 parts of cyclohexane oil, and then heat to 100° C. in a vacuum environment and dehydrate for 30 minutes to obtain a mixed polyol.

[0032] After dehydration, the room temperature is cooled to below 60°C, liquefied MDI (6 parts) and MDI-100 (26 parts) are added to the mixed polyols, heated and stirred at 85°C for 5 hours, samples are taken to determine NCO, and degassing is performed. The prepolymer synthesis is completed.

[0033] Step 2: Prepolymer and curing agent trimethylolpropane (TMP), 5 parts; triisopropanolamine (TIPA), 5 parts; 1,4-butanediol (BDO), 5 parts; 988SG, 10 parts; DMN500, 5 parts; antioxidant, 0.3 parts; anti-hydrolysis agent, 0.3 parts; ultraviolet absorber, 0.3 parts; catalyst, 0.08 parts are quickly stirred at 85°C, with a weight ratio of 100:8.49, poured into a mold after vacuum degassing, and placed in an oven at 115°C for 24 hours for vulcanization molding, and the synthesis of the polar organic solvent-resistant polyurethane elastomer is completed.

[0034] [Example 4]

[0035] Step 1: 80 parts of polyethylene succinate, 20 parts of polycarbonate polyol and 15 parts of cyclohexane oil are mixed, and then heated to 100° C. in a vacuum environment and dehydrated for 30 minutes to obtain a mixed polyol.

[0036] After dehydration, the room temperature is cooled to below 60°C, liquefied MDI (part 5) and MDI-100 (part 25) are added to the mixed polyols, heated and stirred at 85°C for 5 hours, and samples are taken to determine NCO. After degassing, the prepolymer synthesis is completed.

[0037] Step 2: Prepolymer and curing agent trimethylolpropane (TMP), 5 parts; triisopropanolamine (TIPA), 5 parts; 1,4-butanediol (BDO), 5 parts; 988SG, 10 parts; DMN500, 5 parts; antioxidant, 0.3 parts; anti-hydrolysis agent, 0.3 parts; ultraviolet absorber, 0.3 parts; catalyst, 0.08 parts are quickly stirred at 85°C, with a weight ratio of 100:8.43, poured into a mold after vacuum degassing, and placed in an oven at 115°C for 24 hours for vulcanization molding, and the synthesis of the polar organic solvent-resistant polyurethane elastomer is completed.

[0038] [Example 5]

[0039] Step 1: 80 parts of polyethylene succinate, 20 parts of polycarbonate polyol, and 15 parts of cyclohexane oil are mixed, and then heated to 100° C. under vacuum and dehydrated for 30 minutes to obtain a mixed polyol.

[0040] After dehydration, the room temperature is cooled to below 60°C, liquefied MDI (10 parts) and MDI-100 (20 parts) are added to the mixed polyols, heated and stirred at 85°C for 5 hours, samples are taken to determine NCO, and degassing is performed. The prepolymer synthesis is completed.

[0041] Step 2: Prepolymer and curing agent trimethylolpropane (TMP), 5 parts; triisopropanolamine (TIPA), 5 parts; 1,4-butanediol (BDO), 5 parts; 988SG, 10 parts; DMN500, 5 parts; antioxidant, 0.3 parts; anti-hydrolysis agent, 0.3 parts; ultraviolet absorber, 0.3 parts; catalyst, 0.08 parts are quickly stirred at 85°C, with a weight ratio of 100:8.45, poured into a mold after vacuum degassing, and placed in an oven at 115°C for 24 hours for vulcanization molding, and the synthesis of the polar organic solvent-resistant polyurethane elastomer is completed.

[0042] [Example 6]

[0043] Step 1: 80 parts of polyethylene succinate, 20 parts of polycarbonate polyol, and 15 parts of cyclohexane oil are mixed, and then heated to 100° C. under vacuum and dehydrated for 30 minutes to obtain a mixed polyol.

[0044] After dehydration, the room temperature is cooled to below 60°C, liquefied MDI (part 15) and MDI-100 (part 15) are added to the mixed polyols, heated and stirred at 85°C for 5 hours, samples are taken to determine NCO, and degassing is performed. The prepolymer synthesis is completed.

[0045] Step 2: Prepolymer and curing agent trimethylolpropane (TMP), 5 parts; triisopropanolamine (TIPA), 5 parts; 1,4-butanediol (BDO), 5 parts; 988SG, 10 parts; DMN500, 5 parts; antioxidant, 0.3 parts; anti-hydrolysis agent, 0.3 parts; ultraviolet absorber, 0.3 parts; catalyst, 0.08 parts are quickly stirred at 85°C, with a weight ratio of 100:8.46, poured into a mold after vacuum degassing, and placed in an oven at 115°C for 24 hours for vulcanization molding, and the synthesis of the polar organic solvent-resistant polyurethane elastomer is completed.

[0046] [Comparative Example 1]

[0047] The commercially available polyurethane elastomer model is HJR3140 (Shandong Hengjiu Polyurethane)

[0048] [Comparative Example 2]

[0049] The commercially available polyurethane elastic model is N1640 (Shandong Huixin New Material Technology Co., Ltd.)

[0050] The polar organic solvent resistant polyurethane elastomers synthesized in Example 1, Example 2, Example 3, Example 4, Example 5, and Example 6 and Comparative Example 1 and Comparative Example 2 were placed in cyclohexanone for 1, 3, 7, and 14 days after hardness testing. The performance of the polyurethane elastomers is shown in Table 1:

[0051] Table 1 Performance test results of embodiments and comparative examples

[0052]

[0053] Beneficial Effects

[0054] The polar organic solvent resistant polyurethane elastomer of the present invention has excellent polar organic solvent resistance through specific raw material composition and preparation process, and has low swelling rate and high performance retention rate after being immersed in common organic solvents. At the same time, the elastomer maintains good mechanical properties, such as tensile strength, elongation at break, etc., which meet practical application requirements.

[0055] The preparation process is simple, the raw materials are easily available, the cost is relatively low, and it is suitable for large-scale industrial production. It has good processing performance and can be formed by conventional processing methods, such as injection molding, extrusion, etc.

Claims

1. A polar organic solvent-resistant polyurethane elastomer, characterized in that: The raw materials by weight include:

2. The polar organic solvent-resistant polyurethane elastomer according to claim 1, characterized in that: The anti-hydrolysis agent is selected from one or more of STABAXOL I, UN-025, and S-7000.

3. The polar organic solvent-resistant polyurethane elastomer according to claim 1, characterized in that: The ultraviolet absorber is selected from one or more of o-hydroxybenzophenone, o-hydroxybenzotriazole and salicylate.

4. The polar organic solvent-resistant polyurethane elastomer according to claim 1, characterized in that: The catalyst is preferably one or more selected from T-9, DABCO-T-12, and TEA.

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