Polyurethane microporous elastomer composite material for table tennis racket and preparation method thereof

Abstract

The present invention belongs to the technical field of polyurethane elastomers, and specifically relates to a polyurethane microporous elastomer composite material for table tennis rackets and a preparation method thereof. The polyurethane microporous elastomer composite material is composed of component A and component B in a mass ratio of 100:(55-65), wherein component A includes polyether polyol A, a chain extender, a foaming agent and a catalyst, and component B is an isocyanate modified by polyether polyol B. The density, hardness and resilience of the polyurethane microporous elastomer of the present invention are flexibly adjustable, and it has excellent elasticity and aging resistance; its preparation method is simple and easy to operate, and the reaction temperature during the production of products is much lower than the traditional rubber vulcanization temperature, so that the sponge micropores will not lose a large amount of elasticity in the hot state due to cooling, and the sponge micropores are formed in one time, which effectively improves the production efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of polyurethane elastomers, and in particular relates to a polyurethane microporous elastomer composite material for table tennis rackets and a preparation method thereof. Background Art

[0002] Table tennis rackets are generally composed of three parts: base, sponge, and rubber. The sponge needs to comprehensively consider the density, hardness, resilience and other indicators to meet the requirements of athletes with different technical characteristics for sponge performance and help athletes improve the quality of their shots. At the same time, it has sufficient aging resistance to maintain the sponge's performance for a long time without obvious decline, thus extending the service life of the table tennis racket.

[0003] At present, the traditional method of preparing table tennis sponges uses natural rubber or butene rubber as the basic material, adds plasticizers, fillers, foaming agents, sulfur activators, sulfur and other additives, and is prepared through mixing, calendering, molding, vulcanization and other processes. The disadvantage of this process is that after years of application, the elastic properties of rubber sponges have been basically developed to the limit. In addition, this process not only has many production links and a long production cycle, but also the reaction temperature is generally above 100°C and the commonly used temperature is 130-170°C. After high-temperature molding and cooling, the micropores in the rubber sponge will become soft, thereby reducing elasticity. This process generally adjusts the density of the sponge by the amount of plasticizer. If the amount of plasticizer is small, the density and hardness of the sponge are too large, the speed of the board is fast when hitting the ball, and the control of the return ball is difficult. Excessive use of plasticizers will affect the resilience of the sponge, reduce the quality of the return ball, and the migration problem of plasticizers will occur during use.

[0004] Chinese patent CN111073066A discloses a medium-low density high elastic rubber sponge for table tennis rackets and its preparation method, which balances the high elasticity and medium-low density of the table tennis racket sponge by selecting a suitable plasticizer. However, this method does not solve the performance limitations of the rubber itself, nor does it solve the shortcomings of the cumbersome production process of the rubber sponge and the loss of elasticity in the hot state after cooling.

[0005] Chinese patent CN1911990A discloses a method for preparing a high-elastic rubber sponge for table tennis, which overcomes the limitations of natural rubber in terms of performance by introducing butene rubber BR and natural rubber NR with excellent comprehensive performance, but does not solve the disadvantage that the rubber sponge loses its elasticity in the hot state after cooling. Summary of the invention

[0006] The technical problem to be solved by the present invention is: to provide a polyurethane microporous elastomer composite material for table tennis rackets, the density, hardness and rebound rate of which are flexibly adjustable, and which has excellent elasticity and aging resistance; the present invention also provides a preparation method thereof, the process is simple and easy, the reaction temperature when producing the product is much lower than the traditional rubber vulcanization temperature, so that the sponge micropores will not lose a large amount of elasticity in the hot state due to cooling, and the sponge micropores are formed in one step, which effectively improves the production efficiency.

[0007] The polyurethane microporous elastomer composite material for table tennis rackets of the present invention is composed of component A and component B in a mass ratio of 100:(55-65), and the component A includes the following raw materials in parts by mass:

[0008]

[0009]

[0010] The B component is an isocyanate modified by a polyether polyol B, including:

[0011] Polyether polyol B 100 parts,

[0012] Isocyanate 140-150 parts.

[0013] In the present invention, the polyether polyol A is a high-activity polyether polyol using glycerol as an initiator and ethylene oxide as an end-capping agent, and has a number average molecular weight of 5000-8000.

[0014] Preferably, the polyether polyol A is selected from one or more of the following polyether polyols: INOVOL F330N, INOVOL F3600, and INOVOL F822 produced by Shandong INOVOL New Materials Co., Ltd.

[0015] In the present invention, the chain extender is one or more of ethylene glycol (EG), diethylene glycol (DEG), 1,4-butanediol (1,4-BG), 1,3-propylene glycol (1,3-PG), and dipropylene glycol (DPG).

[0016] In the present invention, the foaming agent is water.

[0017] In the present invention, the catalyst is a mixture of a tertiary amine catalyst and an organic tin catalyst.

[0018] Preferably, the tertiary amine catalyst is triethylenediamine solution (A-33), and the organic tin catalyst is dibutyltin dilaurate (T-12).

[0019] In the present invention, the polyether polyol B is a polyether polyol with a functionality of 2 and a number average molecular weight of 1000 to 2000.

[0020] Preferably, the polyether polyol B is selected from one or two of the following polyether polyols: INOVOL C210 and INOVOL C220 produced by Shandong INOVOL New Materials Co., Ltd.

[0021] In the present invention, the isocyanate is one or both of toluene diisocyanate (TDI) and polymethyl polyphenyl polyisocyanate.

[0022] Preferably, the isocyanate is selected from one or more of the following isocyanates: TDI-80 produced by Cangzhou Dahua Group Co., Ltd., PM200 produced by Wanhua Chemical Group Co., Ltd., and 44V20 produced by Bayer AG of Germany.

[0023] In the present invention, the B component further comprises a storage stabilizer accounting for 5 to 10 ppm of the total mass of the B component; the storage stabilizer is one or both of phosphoric acid and benzoyl chloride.

[0024] The method for preparing the polyurethane microporous elastomer composite material for table tennis rackets of the present invention comprises the following steps:

[0025] (1) Component A: polyether polyol A, chain extender, foaming agent and catalyst are uniformly mixed at room temperature to obtain component A;

[0026] (2) Component B: At room temperature, add polyether polyol B into a reaction kettle, raise the temperature to 100-110° C., cool to below 50° C. after vacuum dehydration, add a storage stabilizer and isocyanate, and react at 80-85° C. for 2-3 hours to obtain component B;

[0027] (3) When in use, component A and component B are mixed in a mass ratio of 100:(55-65), injected into a mold, opened after 5-10 minutes, and left to stand and mature for 1-2 hours to obtain a polyurethane microporous elastomer for table tennis rackets.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] (1) The present invention uses polyurethane materials instead of traditional rubber materials, which have better elasticity and aging resistance, and can flexibly adjust indicators such as density, hardness, and rebound rate to meet the needs of table tennis players with different technical characteristics;

[0030] (2) The process reaction temperature used in the present invention is much lower than the traditional rubber vulcanization temperature, so that the sponge micropores will not lose a large amount of elasticity in the hot state due to cooling;

[0031] (3) Component A and component B of the present invention are both liquid at room temperature, which is convenient for storage and use, and one-step molding during production can effectively improve production efficiency. DETAILED DESCRIPTION

[0032] The present invention is further described below with reference to the examples. The raw materials used in the examples, unless otherwise specified, are all commercially available conventional raw materials; the process methods used in the examples, unless otherwise specified, are all conventional methods in the art.

[0033] Some of the raw materials used in the examples are described as follows:

[0034] INOVOL F330N, INOVOL F3600, INOVOL F822, INOVOL C210, INOVOL C220: Shandong Yinuowei New Materials Co., Ltd.;

[0035] A-33: Xindian Chemical Materials (Shanghai) Co., Ltd.

[0036] T-12: American Gas Company;

[0037] TDI-80: Cangzhou Dahua Group Co., Ltd.;

[0038] PM200: Wanhua Chemical Group Co., Ltd.

[0039] 44V20: Bayer AG, Germany.

[0040] Example 1

[0041] A polyurethane microporous elastomer composite material for table tennis rackets, component A is composed of:

[0042]

[0043] Component B is composed of:

[0044]

[0045]

[0046] The preparation method is as follows:

[0047] (1) Component A: Add the various materials in the formula of component A in an accurately weighed amount in sequence, stir at room temperature for 1 hour, and store in a sealed container to obtain component A;

[0048] (2) Component B: Add C210 and C220 to a reactor, heat to 100°C, dehydrate for 2 hours at a pressure of no more than -0.09 MPa, cool to below 50°C, add storage stabilizer and TDI-80, heat to 80°C and react for 2 hours, add PM200 and stir for 30 minutes, cool to a closed state and store, to obtain component B;

[0049] (3) When in use, add component A and component B into the material tank of a low-pressure casting machine respectively, maintain the material temperature at 35-40°C, and inject into the mold at a mass ratio of 100:59. The mold temperature is 40°C. After 5 minutes, the mold is opened and the product is obtained after standing and aging for 1 hour.

[0050] Example 2

[0051] A polyurethane microporous elastomer composite material for table tennis rackets, component A is composed of:

[0052]

[0053] Component B is composed of:

[0054]

[0055] The preparation method is as follows:

[0056] (1) Component A: Add the various materials in the formula of component A in an accurately weighed amount in sequence, stir at room temperature for 1.5 hours, and store in a sealed container to obtain component A;

[0057] (2) Component B: Add C210 and C220 to a reactor, heat to 110°C, dehydrate at a pressure of no more than -0.09 MPa for 2.5 hours, cool to below 50°C, add storage stabilizer and TDI-80, heat to 80°C, react for 2.5 hours, add PM200 and stir for 30 minutes, cool to a closed state and store, to obtain component B;

[0058] (3) When in use, add component A and component B into the material tank of a low-pressure casting machine respectively, maintain the material temperature at 35-40°C, and inject into the mold at a mass ratio of 100:55. The mold temperature is 45°C. After 7 minutes, the mold is opened and the product is obtained after standing and aging for 1 hour.

[0059] Example 3

[0060] A polyurethane microporous elastomer composite material for table tennis rackets, component A is composed of:

[0061]

[0062] Component B is composed of:

[0063]

[0064] The preparation method is as follows:

[0065] (1) Component A: Add the various materials in the formula of component A in an accurately weighed amount in sequence, stir at room temperature for 2 hours, and store in a sealed container to obtain component A;

[0066] (2) Component B: Add C210 and C220 to a reactor, heat to 110°C, dehydrate for 3 hours at a pressure not greater than -0.09 MPa, cool to below 50°C, add a storage stabilizer, add TDI-80, heat to 85°C, react for 3 hours, add PM200 and stir for 30 minutes, cool to a closed state and store to obtain component B;

[0067] (3) When in use, add component A and component B into the material tank of a low-pressure casting machine respectively, maintain the material temperature at 35-40°C, and inject into the mold at a mass ratio of 100:64. The mold temperature is 40°C. After 5 minutes, the mold is opened and the product is obtained after standing and aging for 1 hour.

[0068] Comparative Example 1

[0069] Conventional commercially available table tennis racket polyurethane elastomer.

[0070] The examples 1-3 and the comparative example were subjected to index tests, wherein the rebound rate = rebound height / initial drop height, and the average value was taken after testing 5 groups; the aging resistance test method was to place the test sample in a constant temperature and humidity chamber, maintain the temperature at 50°C and the humidity at 100%, and compare the sponge state after 30 days.

[0071] The test results are shown in Table 1.

[0072] Table 1 Performance test results

[0073]

[0074]

[0075] It can be seen from Table 1 that, compared with Comparative Example 1, the polyurethane elastomers of Examples 1-3 can maintain a higher hardness at a lower density, and have a high rebound rate and good aging resistance.

Claims

1. A polyurethane microporous elastomer composite material for table tennis rackets, characterized in that: The composition is composed of component A and component B in a mass ratio of 100:(55-65), and the component A includes the following raw materials in parts by mass: Polyether polyol A 100 parts, Chain extender 5-8 parts, 0.4-0.6 parts of foaming agent, Catalyst 0.2-0.6 parts; The B component is an isocyanate modified by a polyether polyol B, including: Polyether polyol B 100 parts, 140-150 parts of isocyanate; The polyether polyol A is a high-activity polyether polyol with glycerol as the initiator and ethylene oxide as the end capping agent, and the number average molecular weight is 5000-8000; the polyether polyol A is selected from one or more of the following polyether polyols: INOVOL F330N, INOVOL F3600, and INOVOL F822 produced by Shandong Yinuowei New Materials Co., Ltd.; The polyether polyol B is a polyether polyol with a functionality of 2 and a number average molecular weight of 1000 to 2000; The chain extender is one or more of ethylene glycol, diethylene glycol, 1,4-butanediol, 1,3-propylene glycol, and dipropylene glycol; The foaming agent is water; The isocyanate is one or both of toluene diisocyanate and polymethyl polyphenyl polyisocyanate.

2. The polyurethane microporous elastomer composite material for table tennis rackets according to claim 1, characterized in that: The catalyst is a mixture of a tertiary amine catalyst and an organic tin catalyst.

3. The polyurethane microporous elastomer composite material for table tennis rackets according to claim 2, characterized in that: The tertiary amine catalyst is triethylenediamine solution, and the organic tin catalyst is dibutyltin dilaurate.

4. The polyurethane microporous elastomer composite material for table tennis rackets according to claim 1, characterized in that: The B component further comprises a storage stabilizer accounting for 5 to 10 ppm of the total mass of the B component; the storage stabilizer is one or both of phosphoric acid and benzoyl chloride.

5. A method for preparing the polyurethane microporous elastomer composite material for table tennis rackets according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) Component A: polyether polyol A, chain extender, foaming agent and catalyst are uniformly mixed at room temperature to obtain component A; (2) Component B: At room temperature, add polyether polyol B into a reaction kettle, raise the temperature to 100-110° C., cool to below 50° C. after vacuum dehydration, add a storage stabilizer and isocyanate, and react at 80-85° C. for 2-3 hours to obtain component B; (3) When in use, component A and component B are mixed in a mass ratio of 100:(55-65), injected into a mold, opened after 5-10 minutes, and left to stand and mature for 1-2 hours to obtain a polyurethane microporous elastomer for table tennis rackets.

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