CN107033324B - A wide temperature range polyurethane elastomer damping material based on network structure design and its method and application - Google Patents

Abstract

The invention belongs to the technical field of damping materials, and discloses a wide-temperature-range polyurethane elastomer damping material based on network structure design, and a method and application thereof. The damping material is prepared from the following components: 11-37 parts by weight of polyurethane prepolymer, 7-30 parts by weight of pendant chain prepolymer, and 1-25 parts by weight of hydroxyl-terminated hyperbranched polyester; The polymer is obtained by reacting polyester diol and diisocyanate under the action of a catalyst; the pendant chain prepolymer is obtained by reacting a terminal monohydroxy compound and diisocyanate under the action of a catalyst. The damping material of the present invention has an effective damping temperature range width of about 170°C, excellent damping performance within the temperature range, and its damping factor tanδ≥0.3, and the polyurethane damping material of the present invention has good high and low temperature damping performance, and the high temperature effective damping can reach 120°C, Has good application prospects.

Description

A wide temperature range polyurethane elastomer damping material and method based on network structure design Law and Application

technical field

The invention belongs to the technical field of damping materials, and relates to a polyurethane elastomer, in particular to a wide-temperature-range polyurethane elastomer damping material based on network structure design, and a preparation method and application thereof.

Background technique

With the rapid development of science and technology, the fields of military and civilian products are developing towards low energy consumption, high speed, and lightweight mechanical automation. At the same time, vibration and noise generated by high automation fill every corner of life, and vibration and noise are very important for daily production. The impact on life cannot be underestimated.

Alleviating the problem of vibration and noise has become a top priority, and domestic and foreign researchers have responded to this problem by exploring new damping materials. Wide temperature range and high damping materials are required to be at least in the temperature range of 60°C to 80°C (use ambient temperature range), and their damping factor tanδ ≥ 0.3. High damping value from service temperature to maximum long-term service temperature). Chinese invention patent application CN104448289A relates to a polyether polyol for improving the damping performance of polyurethane, its preparation method and the preparation method of the prepared damping material. Side groups are introduced into the polyether main chain to increase the internal friction force to improve the polyurethane damping, The effective damping temperature range is about 70°C (-10°C～60°C); patent application CN103140522A provides a damping material composition containing branched polymers, and the effective damping temperature range is about 40°C (-20°C～20°C). At present, some scholars have explored the introduction of dangling chains (a molecular chain with one end fixed in a cross-linked network and the other end freely moving) into polymer materials to improve its damping performance. However, damping polymer materials are designed and prepared based on a single molecular structure. The effective damping at high temperature and low temperature is relatively narrow. If the content of the suspension chain is too high, the mechanical properties of the polymer material will be damaged too much, which cannot meet the actual use requirements.

Polyurethane elastomer damping materials have become one of the research focuses of elastomer damping materials due to their advantages such as flexible structural design, controllability of preparation, and low price. However, polyurethane damping materials also have the same shortcomings as viscoelastic damping materials. That is, the damping performance is good below room temperature, but the damping effect above room temperature is not good, so it is necessary to design the structure of the polyurethane elastomer damping material. The polyurethane elastomer is composed of soft and hard segments, which has strong designability and a reasonable free volume fraction (free volume The percentage of pores in the total polymer volume), the introduction of suspension chains, etc. to adjust the compatibility of the soft and hard segments of the polyurethane elastomer, improve the microphase separation, can prepare materials with good damping performance in a wide temperature range, and further expand polyurethane damping materials field and scope of application.

SUMMARY OF THE INVENTION

In order to overcome the shortcomings and deficiencies of the prior art, the purpose of the present invention is to provide a preparation method of a wide-temperature-range polyurethane elastomer damping material based on network structure design. In the invention, the polyester diol and diisocyanate compound are reacted to prepare the polyurethane prepolymer, and then the hanging chain prepolymer is prepared by using the terminal monohydroxy compound and the diisocyanate compound, and the hydroxyl terminal hyperbranched polyester raw material is used as the crosslinking agent and the chain extender. The agent reacts with each prepolymer to obtain a damping material. The damping material prepared by the method of the present invention has an effective damping temperature range of about 170°C (-50°C to 120°C), compared with general wide temperature range high damping materials (which require a temperature range of at least 60°C to 80°C) (within the range of the ambient temperature range), its damping factor tanδ≥0.3), the damping material of the present invention has a wide temperature range, good damping performance and remarkable effect.

Another object of the present invention is to provide a wide temperature-range polyurethane elastomer damping material based on the network structure design obtained by the above preparation method.

The polyurethane elastomer damping material of the present invention has excellent performance, and the reasonable ratio of the cross-chain extender (hydroxyl-terminated hyperbranched polyester raw material) to the prepolymer makes the free volume fraction in the polyurethane elastomer network structure larger; Fixed, the other end can move freely, the dangling chain responds more timely to external stimuli, and its conformation is changeable. Compared with the elastic main chain, it has more relaxation modes. After the external stimulus disappears, the dangling chain recovers its deformation or produces a new conformation. The suspension chain can repeatedly respond to external stimuli, and the introduction of the suspension chain can effectively improve the compatibility of the soft and hard segments. The suspension chain is close to the flexibility of the elastic main chain. The long suspension chain can also effectively prevent the aggregation of hard segments and reduce the polyurethane elastomer The soft and hard segments are separated by microphase separation; the hydroxyl-terminated hyperbranched polyester acts as a cross-chain extender, and the hyperbranched molecular chain and pendant chain have abundant power-supply groups and charge-absorbing groups, which can strengthen the hydrogen bonding effect of the cross-linked network. The synergistic composite effect of free volume, microphase separation and hydrogen bonding gives the polyurethane elastomer good damping performance in a wide temperature range (about 170 °C), and the effective damping at high temperature can reach 120 °C, which is expected to be used in transportation, construction It has been applied in the fields of engineering and so on.

Another object of the present invention is to provide the application of the above-mentioned wide-temperature-range polyurethane elastomer damping material based on network structure design.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A wide-temperature-range polyurethane elastomer damping material based on network structure design is prepared from the following components: 11-37 parts by weight of a polyurethane prepolymer, 7-30 parts by weight of a hanging chain prepolymer, a hydroxyl-terminated hyperbranched polymer 1 to 25 parts by weight of ester;

The polyurethane prepolymer is obtained by reacting polyester diol and diisocyanate under the action of a catalyst, wherein the weight ratio of polyester diol and diisocyanate is (10-30): (1-7), The polyester diol needs to be subjected to vacuum dehydration treatment before the reaction;

The pendant chain prepolymer is obtained by reacting a terminal monohydroxy compound and diisocyanate under the action of a catalyst, wherein the weight ratio of the terminal monohydroxy compound and diisocyanate is (5-20): (2-10).

The hydroxyl-terminated hyperbranched polyester has a terminal hydroxyl number of ≥5 and a molecular weight of ≥500; preferably H101, H102, H103, H104, H201, H202, H203, H204, H301, H302 produced by Wuhan Hyperbranched Resin Technology Co., Ltd. , one or more of H303, H304, H401, H402, H403.

The polyester diol is formed by condensation polymerization of dicarboxylic acid, acid anhydride or lactone and diol.

Preferably, the dibasic acid or acid anhydride is adipic acid, phthalic acid, phthalic anhydride, halophthalic acid, caprolactone, etc., preferably adipic acid; the dihydric alcohol is 1,4 -Butanediol, ethylene glycol, hexanediol, p-neopentyl glycol, diethylene glycol, etc.

The polyester diol is preferably an aliphatic polyester diol.

Preferably, the molecular weight of the polyester diol is 1000-4000.

The diisocyanate in the polyurethane prepolymer is the same or different from the diisocyanate in the pendant chain prepolymer, and the diisocyanate is 2,4-toluene diisocyanate (TDI), isophorone diisocyanate, hexamethylene diisocyanate Isocyanate or 4,4'-diphenylmethane diisocyanate; preferably 2,4-toluene diisocyanate (TDI).

The terminal monohydroxy compound is one or more of polyethylene glycol monomethyl ether, polyethylene glycol monostearate, n-hexanol, stearyl alcohol or triacosanol; preferably polyethylene glycol monomethyl ether.

The molecular weight of the polyethylene glycol monomethyl ether is 350-1000.

The catalyst in the polyurethane prepolymer is the same as or different from the catalyst in the pendant chain prepolymer, and the catalyst is one or more of dibutyltin dilaurate, bismuth carboxylate, potassium carboxylate, and stannous octoate.

A preparation method of a wide-temperature-range polyurethane elastomer damping material based on network structure design, comprising the following steps:

(1) Preparation of polyurethane prepolymer

The polyester diol is heated to 100-120° C., dehydrated in a vacuum to obtain a dehydrated polyester diol; under the protection of an inert gas and stirring at a medium speed, the dehydrated polyester diol and diisocyanate are mixed, and the temperature is raised to 70～80℃, add catalyst, keep the temperature for 1～3h, stop the reaction, obtain elastic main chain prepolymer, namely polyurethane prepolymer; the inert gas is N ₂ ;

(2) Preparation of pendant chain prepolymer

Under the protection of inert gas and stirring at medium speed, the terminal monohydroxy compound is mixed with diisocyanate, the temperature is raised to 50-60 ° C, the catalyst is added, and the reaction is stopped for 1-2 hours to obtain a pendant chain prepolymer; the inert gas is N ₂ ;

(3) Preparation of polyurethane elastomer damping material

Under the protection of inert gas and stirring, add hydroxyl-terminated hyperbranched polyester to the mixture of polyurethane prepolymer and pendant chain prepolymer, stir rapidly, cast molding, remove solvent and bubbles, heat up to 60-80 °C, Keep the temperature for 8 to 24 hours, continue to heat up to 80 to 100 °C, keep the temperature for 1 hour to 6 hours, and complete the curing to obtain a polyurethane elastomer damping material; the hydroxyl-terminated hyperbranched polyester is added in the form of a solution, and the hydroxyl-terminated hyperbranched polyester is added in the form of a solution. Dissolved in the solvent to obtain.

The polyurethane elastomer has a damping factor tanδ ≥ 0.3 in the temperature range of 170 °C; the effective damping at high temperature can reach 120 °C, which is a high-damping polyurethane elastomer material in a wide temperature range;

The solvent described in step (3) is one or more of tetrahydrofuran, dimethylacetamide, toluene, xylene, and acetone.

In the step (1), the vacuum dehydration is carried out under stirring conditions, and the stirring speed is 100-250 r/min; the vacuum dehydration conditions are drying under the pressure of 1-2 MPa for 1.5-3 hours. The rotating speed of the medium-speed stirring in the step (1) is 200-350 r/min.

The addition amount of the catalyst described in step (1) is 0.01‰～5‰ of the weight of polyester diol and isocyanate; the addition amount of the catalyst described in step (2) is 0.01‰～5‰ of the weight of terminal monohydroxy compound and diisocyanate 5‰.

The rotating speed of the medium-speed stirring in the step (2) is 200-350 r/min; the rotating speed of the rapid stirring in the step (3) is 350-500 r/min. The rapid stirring time in step (3) is 5-10 min.

In the preparation of the polyurethane prepolymer, it takes 5 to 10 minutes to raise the temperature to 60-80° C., and it takes 5 to 10 minutes to raise the temperature to 50 to 60° C. in the preparation of the pendant chain prepolymer.

A wide temperature range polyurethane elastomer damping material based on network structure design is prepared by the above preparation method.

The polyurethane elastomer damping material of the present invention has a damping factor tanδ ≥ 0.3 in the temperature range of about 170°C, and at the same time, the effective damping at high temperature can reach 120°C.

In the present invention, the hydroxyl-terminated hyperbranched polyester is cleverly selected as the cross-chain extender to adjust the free volume fraction of the polyurethane elastomer (by adjusting the ratio of the hydroxyl-terminated hyperbranched polyester to the prepolymer, that is, the number of moles of isocyanate groups and hydroxyl groups) The ratio of the number of moles can realize the adjustment of the free volume fraction. The hydroxyl-terminated hyperbranched polyester, on the one hand, has a large molecule, on the other hand, there are many hydroxyl groups at the end, and other cross-linking agents such as TMP (TMP has only 3 hydroxyl groups at the end, In addition, TMP has a small molecular weight. Relatively speaking, the hydroxyl-terminated hyperbranched polyester has at least 5 hydroxyl groups at the end, and the minimum molecular weight is 500. At the same time, the hydrogen bonding of the hyperbranched polyester is stronger. The suspension chain is introduced into the structure, and the cross-linked network structure with a larger free volume fraction is designed. The suspension chain has a larger space for activity, and only one end of the suspension chain is used to fix it, which can have larger free volume holes for a variety of relaxation modes to consume. Mechanical energy. The invention improves the damping performance of the material from three aspects of free volume, microphase separation and hydrogen bonding.

The raw materials of the wide-temperature-range damping polyurethane elastomer synthesized by the invention are readily available in the market, the price is moderate, and the polyurethane itself has good comprehensive properties. The present invention prepares a wide-temperature-range damping polyurethane elastomer based on the network structure design Material. In the present invention, the main chain structure formed by the reaction of diisocyanate (such as: TDI) and polyester diol has better mechanical strength; terminal monohydroxy compound (such as: polyethylene glycol monomethyl ether) and diisocyanate (such as: The pendant chain prepared by TDI) has good flexibility, various relaxation modes, and can consume mechanical energy repeatedly; hydroxyl-terminated hyperbranched polyester is used as a cross-chain extender, and the hydroxyl-terminated hyperbranched end has multiple active hydroxyl groups, which can control the cross-linking during curing. Density, endows the synthetic polymer with a larger free volume fraction, and at the same time, the abundant electron-absorbing and donating groups on the molecule help the cross-linked network to form stronger hydrogen bonds. From the three aspects of free volume, microphase separation, and hydrogen bonding, the synergistic compound effect makes the polyurethane elastomer synthesized and prepared by the present invention as a wide temperature range damping material, the damping factor tanδ≥0.3 in the temperature range of about 170°C, and the high temperature is effective at the same time. The damping can reach 120℃, which can meet the actual use requirements.

Taking TDI as the raw material of the diisocyanate compound and the cross-chain extender hydroxyl-terminated hyperbranched polyester using H201 as an example, the schematic diagram of the reaction mechanism of the present invention is shown in FIG. 1 .

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. The polyurethane damping material of the present invention has a large effective damping temperature range (about 170° C.), excellent damping performance within the temperature range, and its damping factor tanδ≥0.3. The existing polyurethane elastomer has a narrow effective damping temperature range of about 60℃～80℃;

2. The polyurethane damping material of the present invention has good high and low temperature damping performance, and the effective damping at high temperature can reach 120°C, which can meet market application requirements (the operating temperature of the polyurethane elastomer material is generally lower than 100°C), and the effective damping in the low temperature direction can reach -50°C It can also meet the requirements for use in extremely cold regions;

3. The present invention introduces hydroxyl-terminated hyperbranched polyester as a cross-chain extender, adjusts the free volume fraction of the cross-linked network in the polyurethane damping material based on the network structure, and gives the suspension chain in the damping material a larger active free volume fraction, while introducing The suspending chain can enhance the hydrogen bond effect in the cross-linked network, and the present invention improves the damping performance of the polyurethane material from the three aspects of free volume, microphase separation and hydrogen bond effect.

Description of drawings

Fig. 1 is the reaction mechanism schematic diagram of the present invention;

Fig. 2 is the dynamic mechanical spectrogram of damping materials prepared in Example 2 and Example 4 at 10 Hz;

FIG. 3 is the dynamic mechanical spectrum of the damping materials prepared in Comparative Example 1 and Comparative Example 2 at 10 Hz.

Detailed ways

For a better understanding of the present invention, the present invention is further described below with reference to the embodiments and accompanying drawings, but the scope of protection of the present invention is not limited to this.

The polyester diol used in the embodiment and the comparative example has a trade mark of 2200A and a molecular weight of 2000, produced by Shandong Jining Huakai Resin Co., Ltd.;

The diisocyanate compound TDI used in the examples and comparative examples is 2,4-toluene diisocyanate, analytically pure, produced by Tianjin Fuchen Chemical Reagent;

Polyethylene glycol monomethyl ether, analytically pure, with molecular weights of 350, 550, 750, and 1000, produced by Shanghai Aladdin Biochemical Technology Co., Ltd.

The cross-chain extender hydroxyl-terminated hyperbranched polyester is H201, H202, chemically pure, produced by Wuhan Hyperbranched Resin Technology Co., Ltd.

The cross-chain extender 1,1,1-trihydroxypropane (TMP) used in the comparative example was analytically pure, produced by Shanghai Aladdin Biochemical Technology Co., Ltd.

Example 1

A preparation method of a wide-temperature-range polyurethane elastomer damping material based on network structure design, comprising the following steps:

(1) Under the condition of stirring (200r/min), 20 parts by weight of polyester diol is subjected to vacuum drying treatment (the condition of vacuum drying treatment is to dry at 100°C for 2.5h under 1MPa pressure) to obtain pretreatment of polyester diols;

(2) The polyester diol pretreated in step (1) is cooled to room temperature, the vacuum pump is turned off, N ₂ is passed through, medium-speed stirring (250 r/min) is added, 3 parts by weight of TDI are added, the temperature is raised to 80° C., and 0.003 is added dropwise. The catalyst dibutyltin dilaurate in parts by weight is kept for 1.5h, and the reaction is stopped to obtain an elastic main chain prepolymer, that is, a polyurethane prepolymer, which is stored under N atmosphere _;

(3) under the protection of N atmosphere, add ₃ parts by weight of TDI to 10 parts by weight of polyethylene glycol monomethyl ether (molecular weight 550), stir at a medium speed (250r/min), and heat up to 50°C in 5 minutes, Add 0.001 parts by weight of catalyst dibutyltin dilaurate dropwise at a constant speed, keep the temperature for 1h, stop the reaction, obtain the prepolymer of hanging chain, and store it under N atmosphere _;

(4) Take 23 parts by weight of polyurethane prepolymer in step ( ₂ ) and 13 parts by weight of pendant chain prepolymer in step (3) in the reaction vessel, and stir at medium speed (250r/min) under the protection of N atmosphere to obtain a mixture ; Weigh 8 parts by weight of H2O1 cross-chain extender and dissolve it in 15ml of tetrahydrofuran solvent, dissolve it completely, and add it into the mixture of polyurethane prepolymer and pendant chain prepolymer, stir rapidly for 5min (350r/min), pour it on polytetrafluoroethylene In the vinyl fluoride mold, the mold is placed in a vacuum drying box to be evacuated, the solvent and air bubbles are removed, the temperature is raised to 70 °C, and the temperature is kept for 15 hours, and then the temperature is raised to 90 °C, and the temperature is kept for 2 hours.

Example 2

A preparation method of a wide-temperature-range polyurethane elastomer damping material based on network structure design, comprising the following steps:

(1) Under the condition of stirring (200r/min), 30 parts by weight of polyester diol is subjected to vacuum drying treatment (the condition of vacuum drying treatment is to dry at 100°C for 2.5h under 1MPa pressure) to obtain pretreatment of polyester diols;

(2) The polyester diol pretreated in step (1) is lowered to room temperature, the vacuum pump is turned off, N ₂ is passed through, 7 parts by weight of TDI are added under the protection of N ₂ atmosphere, stirred at a medium speed (250r/min), and heated to 80 ℃ ℃, add 0.004 parts by weight of catalyst dibutyltin dilaurate dropwise, keep the temperature for 1.5h, stop the reaction, obtain the elastic main chain prepolymer, namely polyurethane prepolymer, and store it under _N2 atmosphere;

( ₃ ) under the protection of N atmosphere, to 15 parts by weight of polyethylene glycol monomethyl ether (molecular weight 1000), add 5 parts by weight of TDI, stir at a medium speed (250r/min), after heating to 50 ° C in 5 minutes, Add 0.003 parts by weight of catalyst dibutyltin dilaurate dropwise at a constant speed, keep the temperature for 1h, stop the reaction, obtain a pendant chain prepolymer, and store it under N atmosphere _;

(4) get 37 parts by weight of step (2) polyurethane prepolymer and 20 parts by weight of step (3) hanging chain prepolymer in the reaction vessel, and stir at medium speed (250r/min ₎ under the protection of N atmosphere to obtain a mixture; Weigh 12 parts by weight of H201 cross-chain extender and dissolve it in 20ml of tetrahydrofuran solvent, add it to the mixture of polyurethane prepolymer and pendant chain prepolymer after it is completely dissolved, stir rapidly for 5min (350r/min), pour it on polytetrafluoroethylene In the mold, the mold is placed in a vacuum drying box to be evacuated, the solvent and air bubbles are removed, the temperature is raised to 80°C, and the temperature is kept for 12 hours, and then the temperature is raised to 100°C, and the temperature is kept for 2 hours for post-curing to obtain a polyurethane elastomer damping material. The dynamic mechanical spectrum of the damping material prepared in Example 2 at 10 Hz is shown in FIG. 2 .

Example 3

A preparation method of a wide-temperature-range polyurethane elastomer damping material based on network structure design, comprising the following steps:

(1) Under the condition of stirring (200r/min), 15 parts by weight of polyester diol is subjected to vacuum drying treatment (the condition of vacuum drying treatment is to dry at 100°C for 2.5h under 1MPa pressure) to obtain pretreatment of polyester diols;

(2) The polyester diol pretreated in step (1) is lowered to room temperature, the vacuum pump is turned off, N ₂ is passed through, 3 parts by weight of TDI are added, stirred at a medium speed (250 r/min), and the temperature is raised to 80° C. in a few minutes. , 0.0015 parts by weight of catalyst dibutyltin dilaurate was added dropwise, the temperature was kept for 1.5h, and the reaction was stopped to obtain an elastic main chain prepolymer, that is, a polyurethane prepolymer, which was stored under N atmosphere _;

(3) under the protection of N atmosphere, add ₃ parts by weight of TDI to 5 parts by weight of polyethylene glycol monomethyl ether (molecular weight 750), stir at a medium speed (250r/min), heat up to 50 ° C in 5 minutes, dropwise Add 0.0005 parts by weight of catalyst dibutyltin dilaurate, keep the temperature for 1 h, stop the reaction, and obtain a pendant chain prepolymer, which is stored in an atmosphere of N ₂ .

(4) get 18 parts by weight of step (2) polyurethane prepolymer and 8 parts by weight of step (3) hanging chain prepolymer in a three-necked flask, and stir at medium speed (250r/min ₎ under the protection of N atmosphere to obtain a mixture; Weigh 3 parts by weight of H201 cross-chain extender and dissolve it in 10ml of tetrahydrofuran solvent, add it to the mixture of polyurethane prepolymer and pendant chain prepolymer after it is completely dissolved, stir rapidly for 5min (350r/min), pour it on polytetrafluoroethylene In the mold, the mold is placed in a vacuum drying box to be evacuated, the solvent and air bubbles are removed, the temperature is raised to 60 ° C, and the temperature is kept for 24 hours, and then the temperature is raised to 80 ° C, and the temperature is kept for 2 hours for post-curing to obtain a polyurethane elastomer damping material.

Example 4

A preparation method of a wide-temperature-range polyurethane elastomer damping material based on network structure design, comprising the following steps:

(1) Under the condition of stirring (200 r/min), 25 parts by weight of polyester diol is subjected to vacuum drying treatment (the condition of vacuum drying treatment is to dry at 100° C. for 2.5 hours under 1MPa pressure) to obtain pretreatment. of polyester diols;

(2) The polyester diol pretreated in step (1) is lowered to room temperature, the vacuum pump is turned off, N ₂ is passed through, 5 parts by weight of TDI are added under the protection of N ₂ atmosphere, stirred at a medium speed (250r/min), and heated to 80 ℃ After ℃, 0.005 parts by weight of catalyst dibutyltin dilaurate was added dropwise, the temperature was kept for 1.5h, and the reaction was stopped to obtain an elastic main chain prepolymer, that is, a polyurethane prepolymer, which was stored under _N2 atmosphere;

(3) Under the protection of N atmosphere, add ₂ parts by weight of TDI to 6 parts by weight of polyethylene glycol monomethyl ether (molecular weight 350), stir at medium speed (250r/min), heat up to 60°C in 6 minutes, dropwise Add 0.001 parts by weight of catalyst dibutyltin dilaurate, keep the temperature for 1h, stop the reaction, obtain the prepolymer of hanging chain, and store it under N atmosphere _;

(4) get 30 parts by weight of step (2) polyurethane prepolymer and 8 parts by weight of step (3) hanging chain prepolymer in the reaction vessel, and stir at medium speed (250r/min ₎ under N atmosphere protection to obtain mixture; Weigh 17 parts by weight of H2O2 cross-chain extender and dissolve it in 20ml of tetrahydrofuran solvent, add it to the mixture of polyurethane prepolymer and pendant chain prepolymer after it is completely dissolved, stir rapidly for 5min (350r/min), and pour it on polytetrafluoroethylene. In the mold, put the mold in a vacuum drying box to vacuumize, remove the solvent and air bubbles, raise the temperature to 70°C, keep the temperature for 15h, then raise the temperature to 90°C, keep the temperature for 2h for post-curing, and obtain the polyurethane elastomer damping material. The dynamic mechanical spectrum of the damping material prepared in Example 4 at 10 Hz is shown in FIG. 2 .

Example 5

A preparation method of a wide-temperature-range polyurethane elastomer damping material based on network structure design, comprising the following steps:

(1) Under the condition of stirring (200r/min), 20 parts by weight of polyester diol is subjected to vacuum drying treatment (the condition of vacuum drying treatment is to dry at 100°C for 2.5h under 1MPa pressure) to obtain pretreatment of polyester diols;

(2) The polyester diol pretreated in step (1) is lowered to room temperature, the vacuum pump is turned off, N ₂ is passed, 4 parts by weight of TDI are added under the protection of N ₂ atmosphere, and the medium speed is stirred (250 r/min) for 5 minutes. After the temperature is raised to 70°C, 0.006 parts by weight of catalyst dibutyltin dilaurate is added dropwise, the temperature is kept for 2h, and the reaction is stopped to obtain an elastic main chain prepolymer, that is, a polyurethane prepolymer, which is stored in an atmosphere of N ₂ ;

(3) under the protection of N atmosphere, add ₄ parts by weight of TDI to 15 parts by weight of polyethylene glycol monomethyl ether (molecular weight 1000), stir at a medium speed (250r/min), and heat up to 50 ° C in 5 minutes, 0.004 parts by weight of catalyst dibutyltin dilaurate was added dropwise, the temperature was kept for 1.5h, the reaction was stopped, and the suspension chain prepolymer was obtained, which was stored under N atmosphere _;

(4) get 24 parts by weight of step (2) polyurethane prepolymer and 19 parts by weight of step (3) hanging chain prepolymer in the reaction vessel, and stir at medium speed (250r/min ₎ under the protection of N atmosphere to obtain mixture; Weigh 9 parts by weight of H201 cross-chain extender and dissolve it in 20ml of tetrahydrofuran solvent, add it into the mixture of polyurethane prepolymer and pendant chain prepolymer after it is completely dissolved, stir rapidly for 5min (350r/min), pour it on polytetrafluoroethylene In the mold, put the mold in a vacuum drying box to vacuumize, remove the solvent and air bubbles, after exhausting, the temperature is raised to 60 °C, and the temperature is kept for 24 hours. Material.

Example 6

A preparation method of a wide-temperature-range polyurethane elastomer damping material based on network structure design, comprising the following steps:

(1) Under the condition of stirring (200r/min), 30 parts by weight of polyester diol is subjected to vacuum drying treatment (the condition of vacuum drying treatment is to dry at 100°C for 2.5h under 1MPa pressure) to obtain pretreatment of polyester diols;

(2) The polyester diol pretreated in step (1) is lowered to room temperature, the vacuum pump is turned off, N ₂ is passed through, 6 parts by weight of TDI are added under the protection of N ₂ atmosphere, stirred at a medium speed (250 r/min), and heated to 75 ℃ ℃, dropwise add 0.005 parts by weight of catalyst dibutyltin dilaurate, keep the temperature for 2h, stop the reaction, obtain the elastic main chain prepolymer, namely polyurethane prepolymer, and store it under _N2 atmosphere;

(3) under the protection of N atmosphere, add ₄ parts by weight of TDI to 8 parts by weight of polyethylene glycol monomethyl ether (molecular weight 350), stir at a medium speed (250r/min), and heat up to 60°C in 5 minutes, 0.002 parts by weight of catalyst dibutyltin dilaurate was added dropwise, the temperature was kept for 1h, and the reaction was stopped to obtain a pendant chain prepolymer, which was stored under N atmosphere _;

(4) get 36 parts by weight of step (2) polyurethane prepolymer and 12 parts by weight of step (3) hanging chain prepolymer in the reaction vessel, and stir at medium speed (250r/min ₎ under N atmosphere protection to obtain mixture; Weigh 18 parts by weight of H201 cross-chain extender and dissolve it in 25ml of tetrahydrofuran solvent, add it into the mixed solution of polyurethane prepolymer and pendant chain prepolymer after completely dissolving, stir rapidly for 5min (350r/min), pour it on polytetrafluoroethylene In the vinyl mold, place the mold in a vacuum drying box to vacuumize the mold to remove the solvent and air bubbles. After the exhaust is completed, the vacuum drying box is heated to 70 ° C and kept for 24 hours. Then the temperature is raised to 90 ° C, and the temperature is kept for 2 hours for post-curing. A polyurethane elastomer damping material is obtained.

Comparative Example 1

A preparation method of a polyurethane elastomer damping material, comprising the following steps:

(1) Under the condition of stirring (200r/min), 30 parts by weight of polyester diol is subjected to vacuum drying treatment (the condition of vacuum drying treatment is to dry at 100°C for 2.5h under 1MPa pressure) to obtain pretreatment of polyester diols;

(2) The polyester diol pretreated in step (1) is lowered to room temperature, the vacuum pump is turned off, N ₂ is passed through, 7 parts by weight of TDI are added under the protection of N ₂ atmosphere, stirred at a medium speed (250r/min), and heated to 80 ℃ ℃, add 0.006 parts by weight of catalyst dibutyltin dilaurate dropwise, keep the temperature for 1.5h, stop the reaction, and obtain the elastic main chain prepolymer, namely polyurethane prepolymer, which is stored under _N2 atmosphere;

(3) Weigh 2 parts by weight of TMP cross-chain extender and dissolve it in 5ml of acetone solvent, add it into the polyurethane prepolymer after complete dissolution, stir rapidly for 5min (350r/min), pour it into a polytetrafluoroethylene mold, and place the mold Put it in a vacuum drying box to vacuumize, remove the solvent and air bubbles, heat up to 80°C, keep the temperature for 12h, then raise the temperature to 100°C, keep the temperature for 2h for post-curing, and obtain the polyurethane elastomer damping material. The dynamic mechanical spectrum of the damping material prepared in Comparative Example 1 at 10 Hz is shown in Figure 3.

Comparative Example 2

A preparation method of a polyurethane elastomer damping material, comprising the following steps:

(1) Under the condition of stirring (200 r/min), 25 parts by weight of polyester diol is subjected to vacuum drying treatment (the condition of vacuum drying treatment is to dry at 100° C. for 2.5 hours under 1MPa pressure) to obtain pretreatment. of polyester diols;

(2) The polyester diol pretreated in step (1) is lowered to room temperature, the vacuum pump is turned off, N ₂ is passed through, 5 parts by weight of TDI are added under the protection of N ₂ atmosphere, stirred at a medium speed (250r/min), and heated to 80 ℃ ℃, add 0.004 parts by weight of catalyst dibutyltin dilaurate dropwise, keep the temperature for 1.5h, stop the reaction, obtain the elastic main chain prepolymer, namely polyurethane prepolymer, and store it under _N2 atmosphere;

(3) under the protection of N atmosphere, add ₂ parts by weight of TDI to 6 parts by weight of polyethylene glycol monomethyl ether (molecular weight 350), stir at a medium speed (250r/min), and heat up to 60°C in 5 minutes, 0.002 parts by weight of catalyst dibutyltin dilaurate was added dropwise, the temperature was kept for 1h, and the reaction was stopped to obtain a pendant chain prepolymer, which was stored under N atmosphere _;

(4) get 30 parts by weight of step (2) polyurethane prepolymer and 8 parts by weight of step (3) hanging chain prepolymer in the reaction vessel, and stir at medium speed (250r/min ₎ under N atmosphere protection to obtain mixture;

(5) Weigh 2 parts by weight of TMP cross-chain extender and dissolve it in 5ml of acetone solvent, add it into the mixed solution of polyurethane prepolymer and pendant chain prepolymer after completely dissolving, stir rapidly for 5min (350r/min), pour in In the polytetrafluoroethylene mold, place the mold in a vacuum drying box to vacuumize, remove the solvent and air bubbles, heat up to 70 ° C, keep the temperature for 15 hours, then increase the temperature to 90 ° C, keep the temperature for 2 hours for post-curing, and obtain the polyurethane elastomer damping Material. The dynamic mechanical spectrum of the damping material prepared in Comparative Example 2 at 10 Hz is shown in Figure 3.

Performance Testing:

The damping properties of the polyurethane materials of Examples 1 to 6 and Comparative Examples 1 to 2 were analyzed by dynamic mechanical test using a DMA 242C dynamic mechanical analyzer (NETZSCH, Germany). The test conditions were: tensile mode, scanning The temperature range is -100～120℃, the heating rate is 3℃/min, and the test frequency is 10Hz. The test results are shown in Figures 2 and 3.

Figure 2 is a dynamic mechanical spectrum obtained by DMA testing at 10 Hz for the damping materials prepared in Example 2 and Example 4; Figure 3 is a dynamic mechanical spectrum obtained by DMA testing of the damping materials prepared in Comparative Example 1 and Comparative Example 2 at 10 Hz. It is generally considered that the damping factor tanδ≥0.3 is the effective damping performance. It can be seen that the polyurethane elastomer material designed based on the network structure of the present invention has a damping factor tanδ≥0.3 in a wide temperature range (about 170°C temperature range). , The dynamic mechanical spectrum of samples 3, 5, and 6 at 10 Hz is basically similar to that of Examples 2 and 4, and the temperature range of damping factor tanδ≥0.3 is also around 170 °C. (When the damping factor tanδ≥0.3, the effective damping temperature range is about -50℃～120℃).

The embodiments of the present invention are not limited by the above-mentioned examples, and any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principle of the present invention should be equivalent substitutions, and are included in the within the protection scope of the present invention.

Claims (10)

1. A wide temperature range polyurethane elastomer damping material based on network structure design is characterized in that: the preparation is prepared from the following components: 11-37 parts of polyurethane prepolymer, 7-30 parts of hanging chain prepolymer and 1-25 parts of hydroxyl-terminated hyperbranched polyester;

the polyurethane prepolymer is obtained by reacting polyester diol and diisocyanate under the action of a catalyst, wherein the weight ratio of the polyester diol to the diisocyanate is (10-30): (1-7), carrying out vacuum dehydration treatment on the polyester diol before reaction;

the pendant chain prepolymer is obtained by reacting a terminal monohydroxy compound and diisocyanate under the action of a catalyst, wherein the weight ratio of the terminal monohydroxy compound to the diisocyanate is (5-20): (2-10);

the hydroxyl-terminated hyperbranched polyester has the hydroxyl number of more than or equal to 5 and the molecular weight of more than or equal to 500; the terminal monohydroxy compound is more than one of polyethylene glycol monomethyl ether, polyethylene glycol monostearate, n-hexanol, octadecanol or triacontanol.

2. The wide temperature range polyurethane elastomer damping material designed based on a network structure as claimed in claim 1, wherein:

the diisocyanate in the polyurethane prepolymer is the same as or different from the diisocyanate in the hanging chain prepolymer, and the diisocyanate is 2, 4-toluene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate or 4, 4' -diphenylmethane diisocyanate;

the molecular weight of the polyester diol is 1000-4000.

3. The wide temperature range polyurethane elastomer damping material designed based on a network structure as claimed in claim 1, wherein: the hydroxyl-terminated hyperbranched polyester is more than one of H101, H102, H103, H104, H201, H202, H203, H204, H301, H302, H303, H304, H401, H402 and H403 produced by Wuhan hyperbranched resin science and technology Limited;

the diisocyanate in the polyurethane prepolymer and the diisocyanate in the hanging chain prepolymer are 2, 4-toluene diisocyanate;

the terminal monohydroxy compound is polyethylene glycol monomethyl ether.

4. The wide temperature range polyurethane elastomer damping material designed based on a network structure as claimed in claim 1, wherein: the catalyst in the polyurethane prepolymer is the same as or different from the catalyst in the pendant chain prepolymer, and the catalyst is more than one of dibutyltin dilaurate, bismuth carboxylate, potassium carboxylate and stannous octoate;

the hydroxyl-terminated hyperbranched polyester is added in the form of a solution.

5. The preparation method of the wide temperature range polyurethane elastomer damping material based on the network structure design according to any one of claims 1 to 4, characterized in that: the method comprises the following steps:

(1) preparation of polyurethane prepolymers

Heating polyester dihydric alcohol to 100-120 ℃, and performing vacuum dehydration to obtain dehydrated polyester dihydric alcohol; under the protection of inert gas and the stirring at a medium speed, mixing dehydrated polyester diol with diisocyanate, heating to 70-80 ℃, adding a catalyst, keeping the temperature for 1-3 hours, and stopping the reaction to obtain an elastic main chain prepolymer, namely a polyurethane prepolymer; the inert gas is N₂；

(2) Preparation of pendant chain prepolymers

Under the conditions of inert gas protection and medium-speed stirring, mixing a terminal monohydroxy compound with diisocyanate, heating to 50-60 ℃, adding a catalyst, and reacting for 1-2 hours to stop reaction to obtain a suspension chain prepolymer; the inert gas is N₂；

(3) Preparation of polyurethane elastomer damping material

Under the conditions of inert gas protection and stirring, adding end-hydroxyl hyperbranched polyester into a mixture of a polyurethane prepolymer and a suspension chain prepolymer, quickly stirring, casting and molding, removing a solvent and bubbles, heating to 60-80 ℃, keeping the temperature for 8-24 hours, continuously heating to 80-100 ℃, keeping the temperature for 1-6 hours, and finishing curing to obtain a polyurethane elastomer damping material; the hydroxyl-terminated hyperbranched polyester is obtained by adding the hydroxyl-terminated hyperbranched polyester in a solution form and dissolving the hydroxyl-terminated hyperbranched polyester in a solvent.

6. The preparation method of the wide temperature range polyurethane elastomer damping material based on network structure design as claimed in claim 5, wherein: the solvent is more than one of tetrahydrofuran, dimethylacetamide, toluene, xylene and acetone.

7. The preparation method of the wide temperature range polyurethane elastomer damping material based on network structure design as claimed in claim 5, wherein: the vacuum dehydration in the step (1) is carried out under the condition of stirring, and the stirring speed is 100-250 r/min; the vacuum dehydration is carried out for 1.5-3 h under the pressure of 1-2 MPa; the rotating speed of the medium-speed stirring in the step (1) is 200-350 r/min.

8. The preparation method of the wide temperature range polyurethane elastomer damping material based on network structure design as claimed in claim 5, wherein: the adding amount of the catalyst in the step (1) is 0.01-5 per mill of the weight of the polyester diol and the isocyanate; the addition amount of the catalyst in the step (2) is 0.01-5 per mill of the weight of the terminal monohydroxy compound and the diisocyanate.

9. The preparation method of the wide temperature range polyurethane elastomer damping material based on network structure design as claimed in claim 5, wherein: the rotating speed of the medium-speed stirring in the step (2) is 200-350 r/min; the rotating speed of the rapid stirring in the step (3) is 350-500 r/min; and (4) rapidly stirring for 5-10 min in the step (3).

10. The application of the wide temperature range polyurethane elastomer damping material designed based on the network structure according to any one of claims 1 to 4 is characterized in that: the wide temperature range polyurethane elastomer damping material based on the network structure design is used in the fields of traffic transportation and building engineering.

Images