A laminated damping type polyurethane elastomer and a method for preparing the same

Abstract

The present application relates to a kind of laminated damping type polyurethane elastomer and its preparation method, belong to polyurethane technical field.It is made of first layer polyurethane and second layer polyurethane laminated composite, after first layer polyurethane A component and B component mix and cure 10~30min, pour the mixed second layer polyurethane C component and D component, solidification forming, obtain laminated damping type polyurethane elastomer.The damping temperature range of first layer polyurethane material is in low temperature zone, and the damping temperature range of second layer polyurethane material is in high temperature zone, under the premise of controlling the curing time of first layer polyurethane material, two polyurethane materials can be closely bonded together, and a blending layer between the upper and lower two materials can be formed, which can better combine the two materials.The present application effectively widens the damping temperature range of the material, and is relatively convenient to implement, simple process, low synthesis cost, and can be mass-produced.

Description

TECHNICAL FIELD

[0001] The present application relates to a laminated damping type polyurethane elastomer and a preparation method thereof, and belongs to the technical field of polyurethane. BACKGROUND

[0002] Polyurethane is known as the "fifth plastic" due to its excellent mechanical properties, good deformation ability, strong biocompatibility and solvent resistance, and diverse application range. It is prepared from isocyanate and polyol as main raw materials. The combination of isocyanate and polyol with various structures allows the molecular structure of polyurethane to be designed according to the performance. Polyurethane materials are widely used in coal industry, transportation construction, mechanical engineering, electronics and electrical appliances, and biomedical engineering. However, the current research on polyurethane damping materials is still limited to low-cost systems with simple formulations, which cannot meet the development needs of multi-scenario damping materials such as low temperature (-50℃~-30℃), room temperature (10℃~30℃) and high temperature (50℃~).

[0003] The damping temperature range of low-cost simple-formulation polyurethane materials is almost not more than 50℃, and the damping temperature range is fixed. For example, the damping temperature range of polyurethane materials containing polyether polyol 330N is generally -50℃~-10℃. The application of such materials in low-temperature conditions such as frozen soil and high altitude has been verified, but they cannot meet the needs of room temperature and high-temperature damping materials. Therefore, it is urgent to develop a method or process for realizing wide-damping-temperature-range polyurethane materials at low cost.

[0004] Currently, some scholars have proposed a method of laminating two polyurethane materials with different damping temperature ranges to prepare wide-damping-temperature-range polyurethane materials. Nataliia Babkina et al. (Polym Adv Technol. 2023) used the method of first curing the first layer of polyurethane and then pouring the second layer of polyurethane. The DMA test results of the composite sample showed that there were two damping peaks of polyurethane materials, which realized the connection of the temperature range, but the damping temperature range was not widened. SUMMARY

[0005] Therefore, the present application aims to provide a laminated damping polyurethane elastomer and a preparation method thereof. By optimizing the polyurethane formula and the preparation process, the obtained laminated polyurethane elastomer not only realizes the combination of the temperature ranges of the two layers of polyurethane, but also has a wider damping temperature range. The loss factor is higher than 0.2 under various temperature conditions, that is, the material can meet the demand for damping materials under multiple working conditions and can also meet the demand for industrial mass production.

[0006] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows.

[0007] A laminated damping polyurethane elastomer is composed of a first layer of polyurethane and a second layer of polyurethane. After the A component and the B component of the first layer of polyurethane are mixed and cured for 10-30 min, the C component and the D component of the second layer of polyurethane are poured and mixed, and then cured and formed to obtain the laminated damping polyurethane elastomer.

[0008] In terms of the total mass of the raw materials for preparing the A component, the components and their mass fractions are as follows: 88-97% of polyhydric alcohol and 3-12% of diol chain extender. The B component is a prepolymer formed by the prepolymerization of diisocyanate and polyhydric alcohol, and the-NCO value of the prepolymer is between 10 and 15. The molar ratio of the active -OH contained in the A component to the-NCO group contained in the B component is 1:1-1.2.

[0009] In terms of the total mass of the raw materials for preparing the C component, the components and their mass fractions are as follows: 88-97% of polyhydric alcohol and 3-12% of diol chain extender. The D component is a prepolymer formed by the prepolymerization of diisocyanate, trihydric alcohol or polyhydric alcohol, and the-NCO value of the prepolymer is between 4 and 8. The molar ratio of the active -OH contained in the C component to the-NCO group contained in the D component is 1:1-1.2.

[0010] The mass ratio of the first layer of polyurethane to the second layer of polyurethane is 0.8-1.2:1.

[0011] Preferably, in the A component, the polyhydric alcohol is one or more of polyhydric alcohol and polyether 330N polyhydric alcohol. More preferably, the molecular weight of the polyhydric alcohol is 800-1200, and the molecular weight of the polyether 330N polyhydric alcohol is 4600-4800.

[0012] Preferably, in terms of the total mass of the raw materials for preparing the B component, the components and their mass fractions are as follows: 55-65% of isocyanate and 35-45% of polyhydric alcohol.

[0013] Preferably, in the C component, the molecular weight of the polyhydric alcohol is 960-1200.

[0014] Preferably, the raw materials for preparing the D component are as follows, with the total mass of the raw materials being 100%: isocyanate 45%~55%, triol or polytrio 48%~55%.

[0015] Preferably, in the D component, the triol or polytrio is one or more of polycaprolactone triol, castor oil and polyoxypropylene triol. More preferably, the molecular weight of the triol or polytrio is 900~1100.

[0016] Preferably, the polydiol is one or more of polytetramethylene glycol (PTMG), polypropylene glycol (PPG) and polyethylene glycol (PEG).

[0017] Preferably, the diisocyanate is one or more of diphenylmethane diisocyanate (MDI), hexamethylene diisocyanate (HDI) and isophorone diisocyanate (IPDI).

[0018] Preferably, the diol chain extender is one or more of 1,4-butanediol (BDO), 1,3-propanediol (PDO), ethylene glycol (EG) and 1,5-pentanediol (PTDO).

[0019] A preparation method of the laminated damping type polyurethane elastomer according to the present application, the method steps comprising:

[0020] After the raw materials of the A component are mixed uniformly, the A component is obtained, and the raw materials of the B component are mixed for pre-polymerization to obtain the B component; the A component and the B component are preheated to 45~50℃;

[0021] After the raw materials of the C component are mixed uniformly, the C component is obtained, and the raw materials of the D component are mixed for pre-polymerization to obtain the D component; the C component and the D component are preheated to 45~50℃;

[0022] After the preheated A component and the B component are mixed, they are poured into a mold and cured at 70~90℃ for 10~30min, and the preheated mixed C component and D component are added and cured at 70~90℃ for 2~4h, to obtain a laminated damping type polyurethane elastomer.

[0023] Preferably, the pre-polymerization temperature is 80~85℃, and the reaction time is 4~8h.

[0024] Advantages

[0025] The present application provides a kind of laminated damping type polyurethane elastomer, the polyurethane elastomer is formed by two layers of polyurethane material layer casting, wherein the damping temperature range of the first layer polyurethane material is in low temperature zone, the damping temperature range of the second layer polyurethane material is in high temperature zone, under the premise of controlling the curing time of the first layer polyurethane material, two layers of polyurethane material can be closely bonded together, and a blending layer between the upper and lower two layers of material can be formed, which can better combine the two layers of material.The present application effectively widens the material damping temperature range, and is relatively convenient to implement, simple process, low synthesis cost, and can be mass-produced.

[0026] The present application provides a kind of laminated damping type polyurethane material, the curing time of the first layer polyurethane material needs to be strictly controlled, and if the curing time of the first layer material is too short, it will not be able to distinguish the second layer material well, resulting in that the damping temperature range of the two layers of polyurethane material not only cannot be well superimposed, but also appears the phenomenon of damping temperature range moving to the middle;If the curing time of the first layer polyurethane material is too long, it will result in that the two layers of polyurethane material cannot appear the phenomenon of interlayer mutual penetration and dispersion, and the result is also poor;When the second layer of polyurethane material is poured after the first layer of polyurethane material is completely cured, the damping temperature range of the composite material is only the simple superposition of the temperature range of the two layers of material, and does not exceed the range of the damping temperature range of the two layers of material.Only when the curing time of the first layer polyurethane material is controlled well, the cured laminated damping material can not only realize the superposition of the damping temperature range of the two layers of material, but also produce the expansion to high temperature temperature range, which makes the material not only meet the application under low temperature and room temperature, but also meet the requirements of damping material under high temperature;The use temperature and application range are widened.

[0027] The present application provides a kind of laminated damping type polyurethane elastomer, in the preparation of the polyurethane elastomer, all the isocyanate in the B component raw material composition contains-NCO group at both ends, (poly) polyol contains-OH group at both ends, and both can be stored for a long time at room temperature after preliminary synthesis of prepolymer.Subsequently, different types of high molecular chain segments (such as PTMG, PPG, etc.) in A component raw material, crosslinking agent (such as polyether polyol 330N, castor oil, etc.) and chain extender (such as BDO, PDO, etc.) can be added according to different production needs, the above raw materials can be polymerized to produce polyurethane material under normal temperature conditions, and then different effects of finished product can be obtained by adjusting the ratio of A and B components;The method steps are simple, the experimental formula can be changed according to production needs, and industrial production can be carried out.

[0028] The present application provides a laminated damping type polyurethane elastomer, in the preparation of the polyurethane elastomer, the preheating temperature of the prepolymer needs to be kept at 45-50℃, which is the key to the preservation of the prepolymer, and the prepolymer will self-polymerize under the action of temperature of 55-80℃. The two ends of the prepolymer are capped by isocyanate (-NCO), and there is a tendency to polymerize with the hydroxyl groups in the main raw materials such as chain extender and crosslinking agent in the normal temperature environment. This polymerization mode can promote the forward reaction and accelerate the reaction rate.

[0029] The present application provides a laminated damping type polyurethane elastomer, in the preparation of the polyurethane elastomer, the isocyanate content of the prepolymer needs to be controlled, and too low isocyanate content will lead to increased viscosity of the polyurethane, which is not easy to chain extend and difficult to form structure, so that the polyurethane with practical application cannot be obtained. Too high isocyanate content will lead to excessive increase of reaction activity, which is not easy to control the molding and processing of the polyurethane. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 The loss factor-temperature curve of the two-layer polyurethane elastomer and the laminated damping type polyurethane elastomer described in Example 1.

[0031] Figure 2 The loss factor-temperature curve of the laminated damping type polyurethane elastomer in Example 1 and the polyurethane sample in the comparative example. DETAILED DESCRIPTION

[0032] The present application will be further described in detail below in combination with specific examples.

[0033] Example 1

[0034] In this embodiment, the molecular weight of castor oil is 920, the molecular weight of polypropylene glycol in the first layer polyurethane (layer 1) is 1800, the molecular weight of polypropylene glycol in the second layer polyurethane (layer 2) is 960, the molecular weight of polybutylene glycol is 1200, and the molecular weight of polyether polyol 330N is 4600. The mass ratio of the first layer polyurethane to the second layer polyurethane is 1:1.

[0035] (1) 60g of diphenylmethane diisocyanate and 40g of polypropylene glycol were added to a 250mL three-necked flask, and the raw materials were stirred at a speed of 200r / min to mix them uniformly under the action of nitrogen at a temperature of 80℃. After 4h of reaction, the prepolymer of the first layer polyurethane (B component) was obtained. 62g of diphenylmethane diisocyanate and 38g of castor oil were added to a 250mL three-necked flask, and the raw materials were stirred at a speed of 200r / min to mix them uniformly under the action of nitrogen at a temperature of 80℃. After 4h of reaction, the prepolymer of the second layer polyurethane (D component) was obtained.

[0036] 0.3842 g of two kinds of prepolymer was respectively dissolved in 25 mL of di-n-butylamine toluene solution, heated at 50 °C for 20 min to make it fully dissolved, 4 drops of bromocresol blue indicator was added, then 50 mL of isopropyl alcohol was added to completely dissolve the indicator; using 0.1023 mol / L of dilute hydrochloric acid was titrated to obtain the isocyanate content of 17.00% and 12.00% in the prepolymer respectively; the ratio of the mass of bromocresol blue in the bromocresol blue indicator (g) and the volume of the solvent sodium hydroxide (mL) is 1:1000, and the concentration of the sodium hydroxide is 0.1 mol / L.

[0037] (2) The titrated prepolymer was preheated to 50 °C, and the dehydrated alcohol raw material was preheated to 50 °C.

[0038] (3) 18.95 g of polybutylene glycol, 9.62 g of polyether polyol 330N and 1.77 g of 1,4-butanediol (A component) were sequentially added to the container, then 19.75 g of the first layer of polyurethane prepolymer was added, and the solution was stirred at a stirring rate of 2000 r / min for 60 s; after pouring into a polytetrafluoroethylene container, it was placed in an oven at 70 °C for 13 min, then 22.32 g of polypropylene glycol and 2 g of 1,4-butanediol (C component) were sequentially added to another container, then 25.68 g of the second layer of polyurethane prepolymer was added, and the solution was stirred at a stirring rate of 2000 r / min for 60 s, then poured into the above polytetrafluoroethylene container and cured at 70 °C for 2 h to obtain a laminated damping type polyurethane elastomer.

[0039] Example 2

[0040] In this embodiment, the molecular weight of the polycaprolactone triol is 1000, the molecular weight of the polypropylene glycol in the first layer of polyurethane is 2000, the molecular weight of the polypropylene glycol in the second layer of polyurethane is 1000, the molecular weight of the polybutylene glycol is 1500, and the molecular weight of the polyether polyol 330N is 4700. The mass ratio of the first layer of polyurethane to the second layer of polyurethane is 1:1.

[0041] (1) 50 g of hexamethylene diisocyanate and 50 g of polypropylene glycol were added to a 250 mL three-necked flask, heated to 80 °C in a nitrogen environment, and the raw materials were stirred at a rate of 200 r / min to make them uniformly mixed, and the first layer of polyurethane prepolymer (B component) was obtained after 4 h of reaction. 50 g of diphenylmethane diisocyanate and 50 g of polycaprolactone triol were added to a 250 mL three-necked flask, heated to 80 °C in a nitrogen environment, and the raw materials were stirred at a rate of 200 r / min to make them uniformly mixed, and the second layer of polyurethane prepolymer (D component) was obtained after 4 h of reaction.

[0042] 0.3269g of two kinds of prepolymer respectively were dissolved in 25mL of di-n-butylamine toluene solution, heated at 50°C for 20min to make it fully dissolved, 4 drops of bromocresol blue indicator was added, then 50mL of isopropyl alcohol was added to completely dissolve the indicator; using 0.1023mol / L of dilute hydrochloric acid was titrated to obtain the isocyanate content of the prepolymer was 17.12% and 11.89% respectively; the ratio of the mass of bromocresol blue in the bromocresol blue indicator (g) and the volume of the solvent sodium hydroxide (mL) was 1:1000, the concentration of sodium hydroxide was 0.1mol / L.

[0043] (2) The titrated prepolymer was preheated to 50°C, and the dehydrated alcohol raw material was preheated to 50°C.

[0044] (3) 21.43g of polybutylene glycol, 8.89g of polyether polyol 330N and 1.35g of 1,3-propanediol (A component) were sequentially added to the container, then 18.33g of the first layer of polyurethane prepolymer was added, and the solution was stirred at a stirring rate of 2000r / min for 60s; after pouring into a polytetrafluoroethylene container, it was placed in a 70°C oven for 15min, then 22.80g of polypropylene glycol and 1.96g of 1,4-butanediol (C component) in step (3) were sequentially added to another container, then 25.24g of the second layer of polyurethane prepolymer was added, and the solution was stirred at a stirring rate of 2000r / min for 60s, then poured into the above polytetrafluoroethylene container and solidified at 70°C for 2h to obtain a laminated damping type polyurethane elastomer.

[0045] Example 3

[0046] The molecular weight of the polypropylene oxide in this example was 1100, the molecular weight of the polypropylene glycol in the first layer of polyurethane was 2200, the molecular weight of the polypropylene glycol in the second layer of polyurethane was 1200, the molecular weight of the polyether polyol 330N was 4800, and the molecular weight of the polybutylene glycol was 1700. The mass ratio of the first layer of polyurethane to the second layer of polyurethane was 1:1.

[0047] (1) 58g of isophorone diisocyanate and 42g of polypropylene glycol were added to a 250mL three-necked flask, heated to 80°C in a nitrogen environment, and the raw materials were stirred at a rate of 200r / min to make them uniformly mixed, and the first layer of polyurethane prepolymer (B component) was obtained after reacting for 4h. 60g of toluene diisocyanate and 40g of polypropylene oxide were added to a 250mL three-necked flask, heated to 80°C in a nitrogen environment, and the raw materials were stirred at a rate of 200r / min to make them uniformly mixed, and the second layer of polyurethane prepolymer (D component) was obtained after reacting for 4h.

[0048] 0.3524g of two kinds of prepolymer was respectively dissolved in 25mL of di-n-butylamine toluene solution, heated at 50°C for 20min to make it fully dissolved, 4 drops of bromocresol blue indicator was added, then 50mL of isopropyl alcohol was added to completely dissolve the indicator; using 0.1023mol / L of dilute hydrochloric acid was titrated to obtain the isocyanate content of 16.64% and 12.18% in the prepolymer; the ratio of the mass of bromocresol blue in the bromocresol blue indicator (g) and the volume of the solvent sodium hydroxide (mL) was 1:1000, and the concentration of the sodium hydroxide was 0.1mol / L.

[0049] (2) The titrated prepolymer was preheated to 50°C, and the dehydrated alcohol raw material was preheated to 50°C.

[0050] (3) 22.77g of polybutylene glycol, 8.51g of polyether polyol 330N and 1.03g of ethylene glycol (A component) were sequentially added to the container, then 17.45g of the first layer of polyurethane prepolymer was added, and the solution was stirred at a stirring rate of 2000r / min for 60s; after pouring into a polytetrafluoroethylene container, it was placed in an oven at 70°C for 18min, then 24.80g of polypropylene glycol and 2.05g of 1,5-pentanediol (C component) in step (3) were sequentially added to another container, then 23.14g of the second layer of polyurethane prepolymer was added, and the solution was stirred at a stirring rate of 2000r / min for 60s, then poured into the above polytetrafluoroethylene container and solidified at 70°C for 2h to obtain a laminated damping type polyurethane elastomer.

[0051] Example 4

[0052] The molecular weight of the polycaprolactone triol in this example was 1120, the molecular weight of the polypropylene glycol in the first layer of polyurethane was 2080, the molecular weight of the polypropylene glycol in the second layer of polyurethane was 1150, the molecular weight of the polybutylene glycol was 1460, and the molecular weight of the polyether polyol 330N was 4750. The mass ratio of the first layer of polyurethane to the second layer of polyurethane was 1.2:1.

[0053] (1) 51g of hexamethylene diisocyanate and 49g of polypropylene glycol were added to a 250mL three-necked flask, heated to 80°C in a nitrogen environment, and the raw materials were stirred at a rate of 200r / min to make them uniformly mixed, and the first layer of polyurethane prepolymer (B component) was obtained after 4h of reaction. 51g of diphenylmethane diisocyanate and 49g of polycaprolactone triol were added to a 250mL three-necked flask, heated to 80°C in a nitrogen environment, and the raw materials were stirred at a rate of 200r / min to make them uniformly mixed, and the second layer of polyurethane prepolymer (D component) was obtained after 4h of reaction.

[0054] 0.3493g of two kinds of prepolymer was respectively dissolved in 25mL of di-n-butylamine toluene solution, heated at 50°C for 20min to make it fully dissolved, 4 drops of bromocresol blue indicator was added, then 50mL of isopropyl alcohol was added to completely dissolve the indicator; using 0.1023mol / L of dilute hydrochloric acid was titrated to obtain the isocyanate content of 17.26% and 11.95% in the prepolymer; the ratio of the mass of bromocresol blue in the bromocresol blue indicator (g) and the volume of the solvent sodium hydroxide (mL) is 1:1000, and the concentration of the sodium hydroxide is 0.1mol / L.

[0055] (2) The titrated prepolymer was preheated to 50°C, and the dehydrated alcohol raw material was preheated to 50°C.

[0056] (3) 21.69g of polybutylene glycol, 8.56g of polyether polyol 330N and 1.49g of 1,4-butanediol (A component) were sequentially added to the container, then 18.86g of the first layer of polyurethane prepolymer was added, and the solution was stirred at a stirring rate of 2000r / min for 60s; after pouring into a polytetrafluoroethylene container, it was placed in an oven at 70°C for 10min, then 22.53g of polypropylene glycol and 2.06g of 1,5-pentanediol (C component) in step (3) were sequentially added to another container, then 25.46g of the second layer of polyurethane prepolymer was added, and the solution was stirred at a stirring rate of 2000r / min for 60s, then poured into the above polytetrafluoroethylene container and solidified at 70°C for 2h to obtain a laminated damping type polyurethane elastomer.

[0057] Example 5

[0058] In this embodiment, the molecular weight of the polypropylene oxide is 1000, the molecular weight of the polypropylene glycol in the first layer of polyurethane is 2000, the molecular weight of the polypropylene glycol in the second layer of polyurethane is 1000, the molecular weight of the polybutylene glycol is 1500, and the molecular weight of the polyether polyol 330N is 4700. The mass ratio of the first layer of polyurethane to the second layer of polyurethane is 1:1.

[0059] (1) 53g of hexamethylene diisocyanate and 47g of polypropylene glycol were added to a 250mL three-necked flask, heated to 80°C in a nitrogen environment, and the raw materials were stirred at a rate of 200r / min to make them uniformly mixed, and the first layer of polyurethane prepolymer (B component) was obtained after 4h of reaction. 52g of diphenylmethane diisocyanate and 48g of polycaprolactone triol were added to a 250mL three-necked flask, heated to 80°C in a nitrogen environment, and the raw materials were stirred at a rate of 200r / min to make them uniformly mixed, and the second layer of polyurethane prepolymer (D component) was obtained after 4h of reaction.

[0060] Take 0.3325g of two kinds of prepolymer respectively into 25ml of di-n-butylamine toluene solution, heat at 50℃ for 20min to make it fully dissolved, add 4 drops of bromocresol blue indicator, then add 50ml of isopropyl alcohol to dissolve the indicator completely; use 0.1023mol / L dilute hydrochloric acid to titrate respectively, the isocyanate content in the prepolymer is 17.06% and 12.09% respectively; the ratio of the mass of bromocresol blue in the bromocresol blue indicator (g) and the volume of solvent sodium hydroxide (ml) is 1:1000, and the concentration of sodium hydroxide is 0.1mol / L.

[0061] (2) Preheat the titrated prepolymer to 50℃, and preheat the dehydrated alcohol raw material to 50℃.

[0062] (3) Add 21.43g of polybutylene glycol, 8.89g of polyether polyol 330N and 1.35g of 1,4-butanediol (A component) into the container in turn, then add 18.33g of the first layer of polyurethane prepolymer, and stir the solution at a stirring rate of 2000r / min for 60s; pour it into a container made of polytetrafluoroethylene, and put it into an oven at 70℃ for 25min, then add 22.80g of polypropylene glycol and 1.96g of 1,3-propanediol (C component) into another container in turn, then add 25.24g of the second layer of polyurethane prepolymer, stir the solution at a stirring rate of 2000r / min for 60s, and then pour it into the above-mentioned polytetrafluoroethylene container, and solidify it at 70℃ for 2h to obtain a laminated damping type polyurethane elastomer.

[0063] Comparative Example 1

[0064] In this comparative example, steps (1)-(2) are the same as in Example 1, and step (3) is: add 18.95g of polybutylene glycol, 9.62g of polyether polyol 330N and 1.77g of 1,4-butanediol (A component) into the container in turn, then add 19.75g of the first layer of polyurethane prepolymer, and stir the solution at a stirring rate of 2000r / min for 60s; pour it into a container made of polytetrafluoroethylene, and solidify it at 70℃ for 3min, then add 22.32g of polypropylene glycol and 2g of 1,4-butanediol (C component) into another container in turn, then add 25.68g of the second layer of polyurethane prepolymer, stir the solution at a stirring rate of 2000r / min for 60s, and then pour it into the above-mentioned polytetrafluoroethylene container, and solidify it at 70℃ for 2h to obtain a damping type polyurethane elastomer.

[0065] Comparative Example 2

[0066] In the present comparative example, steps (1)-(2) are the same as in Example 1, and step (3) is: first, 18.95 g of polytetramethylene glycol, 9.62 g of polyether polyol 330N, and 1.77 g of 1,4-butanediol (A component) are sequentially added to a container, then 19.75 g of the first layer of polyurethane prepolymer is added, and the solution is stirred at a stirring rate of 2000 r / min for 60 s; after pouring into a container of polytetrafluoroethylene, it is placed in an oven at 70°C for 5 min, then 22.32 g of polypropylene glycol and 2 g of 1,4-butanediol (C component) are sequentially added to another container, then 25.68 g of the second layer of polyurethane prepolymer is added, and the solution is stirred at a stirring rate of 2000 r / min for 60 s, then poured into the above-mentioned polytetrafluoroethylene container and cured at 70°C for 2 h, to obtain a damping polyurethane elastomer.

[0067] Comparative Example 3

[0068] In the present comparative example, steps (1)-(2) are the same as in Example 1, and step (3) is: first, 18.95 g of polytetramethylene glycol, 9.62 g of polyether polyol 330N, and 1.77 g of 1,4-butanediol (A component) are sequentially added to a container, then 19.75 g of the first layer of polyurethane prepolymer is added, and the solution is stirred at a stirring rate of 2000 r / min for 60 s; after pouring into a container of polytetrafluoroethylene, it is placed in an oven at 70°C for 5 min, then 22.32 g of polypropylene glycol and 2 g of 1,4-butanediol (C component) are sequentially added to another container, then 25.68 g of the second layer of polyurethane prepolymer is added, and the solution is stirred at a stirring rate of 2000 r / min for 60 s, then poured into the above-mentioned polytetrafluoroethylene container and cured at 70°C for 2 h, to obtain a damping polyurethane elastomer.

[0069] The final products prepared in Examples 1-5 and Comparative Examples 1-3 were subjected to DMA testing, the testing conditions were tensile mode, and the DMA testing was performed on a 30 mm x 5 mm x 2 mm long strip-shaped sample at a frequency of 10 Hz and a temperature range of -100°C to 100°C. The results are shown in Table 1. Figure 1 As shown in Table 1, Example 1 successfully combined the loss peaks of the two layers of polyurethane materials, and not only achieved the continuity of the loss peaks of the two layers of polyurethane materials, but also achieved the extension of high-temperature damping in the range of loss factor ≥0.2. The test results of Examples 2-3 were similar to those of Example 1. Examples 4-5 had similar damping temperature range effects to Examples 1-3.

[0070] The final products prepared in Examples 1-5 and Comparative Examples 1-3 were subjected to DMA testing, the testing conditions were tensile mode, and the DMA testing was performed on a 30 mm x 5 mm x 2 mm long strip-shaped sample at a frequency of 10 Hz and a temperature range of -100°C to 100°C. The results are shown in Table 1. Figure 2As shown, the curing time of the first layer of polyurethane has a great influence on the damping temperature range of the whole material. Too short or no curing time will lead to the tendency of the laminated material to a single structure (Comparative Example 1 and Comparative Example 2), which cannot integrate the damping temperature range of the two layers of material. Too long curing time of the first layer of polyurethane (Comparative Example 3) will lead to the inability of the two layers of elastomers to penetrate each other, resulting in the phenomenon of integrating the damping temperature range of the two layers of material, but failing to broaden the damping temperature range on this basis.

[0071] In summary, the application includes but is not limited to the above embodiments, any equivalent replacement or partial improvement made under the spirit and principles of the application will be considered within the protection scope of the application.

Claims

1. A laminated damping type polyurethane elastomer, characterized by: The first layer polyurethane and the second layer polyurethane are laminated and compounded, the first layer polyurethane A component and B component are mixed and cured for 10-30 minutes, then the mixed second layer polyurethane C component and D component are poured and cured to form, the two layers of polyurethane material are tightly bonded together, at the same time, a blending layer is formed between the upper and lower two layers of material, and a laminated damping type polyurethane elastomer is obtained; In terms of the total mass of raw materials for preparing the A component being 100%, the components and their mass fractions are as follows: polyhydric alcohol 88%-97% and diol chain extender 3%-12%; the B component is a prepolymer formed by pre-polymerization of diisocyanate and polyhydric alcohol, with the -NCO value being between 10 and 15; the molar ratio of active -OH contained in the A component to -NCO groups contained in the B component is 1:1-1.2; In terms of the total mass of raw materials for preparing the C component being 100%, the components and their mass fractions are as follows: polyhydric alcohol 88%-97% and diol chain extender 3%-12%; the D component is a prepolymer formed by pre-polymerization of diisocyanate, trihydric alcohol or polyhydric alcohol, with the -NCO value being between 4 and 8; the molar ratio of active -OH contained in the C component to -NCO groups contained in the D component is 1:1-1.2; The mass ratio of the first layer polyurethane to the second layer polyurethane is 0.8-1.2:

1.

2. A laminated damping polyurethane elastomer according to claim 1, characterized in that: In the A component, the polyhydric alcohol is one or more of polyhydric alcohol and polyether 330N polyhydric alcohol; the molecular weight of the polyhydric alcohol is 800-1200, and the molecular weight of the polyether 330N polyhydric alcohol is 4600-4800.

3. A laminated damping polyurethane elastomer according to claim 1, characterized in that: In terms of the total mass of raw materials for preparing the B component being 100%, the components and their mass fractions are as follows: isocyanate 55%-65% and polyhydric alcohol 35%-45%.

4. A laminated damping polyurethane elastomer as claimed in claim 1, characterized in that: In the C component, the molecular weight of the polyhydric alcohol is 960-1200.

5. A laminated, damped polyurethane elastomer as in claim 1, wherein: In terms of the total mass of raw materials for preparing the D component being 100%, the components and their mass fractions are as follows: isocyanate 45%-55%, trihydric alcohol or polyhydric alcohol 48%-55%.

6. A laminated, damped polyurethane elastomer as in claim 1, wherein: In the D component, the trihydric alcohol or polyhydric alcohol is one or more of polycaprolactone triol, castor oil and polyoxypropylene triol; the molecular weight of the trihydric alcohol or polyhydric alcohol is 900-1100.

7. A laminated damping polyurethane elastomer according to any one of claims 1 to 6, characterized in that: The polyhydric alcohol is one or more of polybutylene glycol, polypropylene glycol and polyethylene glycol.

8. A laminated damping polyurethane elastomer according to any one of claims 1 to 6, characterized in that: The diisocyanate is one or more of diphenylmethane diisocyanate, hexamethylene diisocyanate and isophorone diisocyanate.

9. A laminated damping polyurethane elastomer according to any one of claims 1 to 6, characterized in that: The diol chain extender is one or more of 1,4-butanediol, 1,3-propanediol, ethylene glycol and 1,5-pentanediol.

10. A process for the production of the laminated damping polyurethane elastomer according to any one of claims 1 to 9, characterized in that: The method steps include: The raw materials of the A component are mixed uniformly to obtain the A component, and the raw materials of the B component are mixed and pre-polymerized to obtain the B component; the A component and the B component are preheated to 45-50°C; The raw materials of the C component are mixed uniformly to obtain the C component, and the raw materials of the D component are mixed and pre-polymerized to obtain the D component; the C component and the D component are preheated to 45-50°C; The raw materials of the C component are mixed uniformly to obtain the C component, and the raw materials of the D component are mixed and pre-polymerized to obtain the D component; the C component and the D component are preheated to 45-50°C; The preheated A component and B component are mixed and poured into a mold, and cured at 70~90℃ for 10~30min, the preheated mixed C component and D component are added, and cured at 70~90℃ for 2~4h, to obtain a laminated damping type polyurethane elastomer; The prepolymerization temperature is 80~85℃, and the reaction time is 4~8h.

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