Ceramic shape memory polymer, ceramic component and preparation method of ceramic component

Abstract

The invention relates to a ceramizable shape memory polymer, a ceramic component and a preparation method of the ceramizable shape memory polymer, and belongs to the technical field of shape memory materials, and the ceramizable shape memory polymer is prepared from the following raw materials: 4, 4 '-bismaleimidodiphenylmethane, 1, 3-bis (4-aminophenoxy) benzene, bis (aminopropyl)-terminated polydimethylsiloxane and a curing agent. According to the ceramizable shape memory polymer provided by the invention, shape editing can be carried out in the heating process, ceramization can be realized at a relatively low temperature without the help of ceramic forming particles, a ceramic component can be obtained, the preparation requirements of the ceramic component with a complex structure can be met, and the application scene of the shape memory polymer is widened.

Description

Technical Field

[0001] The invention relates to the technical field of shape memory materials, and in particular to a ceramicizable shape memory polymer, a ceramic component and a preparation method thereof. Background Art

[0002] Shape memory polymer (SMP) is an emerging smart material with a unique shape memory effect. It can automatically return to its original shape under external stimulation. It has the advantages of strong designability, diverse stimulation methods, light weight and high strength. It has broad application prospects in aerospace, biomedicine, intelligent manufacturing, mechanical engineering and other fields. Ceramic materials, as one of the most promising materials besides metal materials and polymer materials, have been widely used in aerospace, biomedicine, mechanical structure and other fields. In particular, high-temperature resistant ceramics are crucial to the aerospace field. However, shape memory polymer materials do not have high temperature resistance and have the problem of low strength at high temperatures, which makes it difficult to meet the requirements of use in high temperature environments or even under open flames. With the development of aerospace, electronic energy and other fields, higher requirements are placed on the complexity of ceramic components. However, the brittleness, low impact resistance and fragility of ceramic materials themselves make the forming process of special-shaped ceramics complicated, limiting the expansion of their application fields.

[0003] Therefore, there is an urgent need to provide a ceramic shape memory polymer that can be shape-programmed during the heating process and can be used to form ceramic components under high-temperature sintering, so as to assist in the forming of ceramic components with complex structures and is expected to broaden its application areas. Summary of the invention

[0004] In response to one or more technical problems existing in the prior art, the present invention provides a ceramic shape memory polymer, a ceramic component and a preparation method thereof. The ceramic shape memory polymer provided by the present invention can be shape-edited during the heating process and can be ceramicized to obtain a ceramic component at a relatively low sintering temperature without the aid of ceramic-forming particles. It can meet the preparation requirements of ceramic components with complex structures and broaden the application scenarios of shape memory polymers.

[0005] The present invention provides a ceramic shape memory polymer in a first aspect. The raw materials for preparing the ceramic shape memory polymer include: 4,4'-bismaleimidodiphenylmethane, 1,3-bis(4-aminophenoxy)benzene, bisaminopropyl-terminated polydimethylsiloxane and a curing agent.

[0006] Preferably, the molar ratio of 4,4'-bismaleimidodiphenylmethane to 1,3-bis(4-aminophenoxy)benzene is 1:0.1 to 0.9;

[0007] The molar ratio of 4,4'-bismaleimidodiphenylmethane to bisaminopropyl-terminated polydimethylsiloxane is 1:0.1-0.9, and preferably, the average molecular weight of bisaminopropyl-terminated polydimethylsiloxane is 500-5000; and / or

[0008] The molar ratio of 4,4'-bismaleimidodiphenylmethane to the curing agent is 1:0.1-1. Preferably, the curing agent is a curing agent with epoxy group double end-capping. More preferably, the curing agent includes but is not limited to one or more of epoxy group double end-capped polydimethylsiloxane, bisphenol A diglycidyl ether, and 1,4-butanediol diglycidyl ether.

[0009] Preferably, the raw materials for preparing the ceramizable shape memory polymer further include at least one of room temperature curing silicone rubber and ceramic material.

[0010] Preferably, the amount of the room temperature curing silicone rubber is no more than twice the mass of 4,4'-bismaleimidodiphenylmethane, and preferably, the room temperature curing silicone rubber is an addition type silicone rubber; and / or

[0011] The amount of the ceramic material used is no more than twice the mass of 4,4'-bismaleimidodiphenylmethane. Preferably, the ceramic material includes but is not limited to one or more of zirconium boride, zirconium oxide, aluminum oxide, and silicon dioxide.

[0012] In a second aspect, the present invention provides a method for preparing the ceramic shape memory polymer according to the first aspect, the preparation method comprising:

[0013] S1. mixing 4,4'-bismaleimidodiphenylmethane, 1,3-bis(4-aminophenoxy)benzene, bisaminopropyl-terminated polydimethylsiloxane and a solvent, and performing a prepolymerization reaction to obtain a prepolymer;

[0014] S2. mixing the prepolymer and the curing agent, removing the solvent to obtain a premix;

[0015] S3. Thermally curing the premix to obtain a ceramizable shape memory polymer.

[0016] Preferably, the prepolymerization reaction is carried out by condensing and reflux at 40 to 90° C. for 18 to 36 hours;

[0017] The temperature of the thermal curing is 50-200°C and the time is 3-10 hours; preferably, the thermal curing is firstly kept at 40-60°C for 1-2 hours, then kept at 100-130°C for 1-4 hours, and finally kept at 200-220°C for 1-4 hours; and / or

[0018] The solvent is at least one of tetrahydrofuran, dichloromethane and acetone.

[0019] Preferably, the premix further comprises at least one of room temperature curing silicone rubber and ceramic material.

[0020] The present invention provides a ceramic component in a third aspect, which is obtained by sintering at a high temperature using the ceramicizable shape memory polymer described in the first aspect.

[0021] Preferably, the high temperature sintering temperature is 800-1600° C., and the sintering atmosphere is nitrogen, argon or air.

[0022] Preferably, the method further comprises temporarily shaping the ceramizable shape memory polymer before the high-temperature sintering.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects:

[0024] The ceramicizable shape memory polymer prepared by the present invention using 4,4'-bismaleimidodiphenylmethane, 1,3-bis(4-aminophenoxy)benzene, bisaminopropyl-terminated polydimethylsiloxane and a curing agent as raw materials can be shape-edited during the heating process without the aid of ceramic-forming particles. Ceramic components can be obtained by ceramicization at a relatively low sintering temperature, which can meet the preparation requirements of ceramic components with complex structures, broaden the application scenarios of shape memory polymers, and is expected to be applied to the fields of smart solar panel deployment, smart hinges, smart pod poles, ceramic catalyst carriers, etc.

[0025] The ceramicizable shape memory polymer provided by the present invention can be made into a ceramic component precursor with an initial shape. Its shape memory function can be used to give the ceramic component precursor a temporary shape before transportation and storage, thereby achieving the purpose of saving storage space and protecting fragile parts of the component during transportation and storage. During the sintering process, the ceramic component precursor with a temporary shape will automatically return to the ceramic component precursor with an initial shape, and finally form a ceramic component with the initial shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 is the DMA curve of the ceramicizable shape memory polymer obtained in Example 1;

[0028] Figure 2This is a physical picture of the shape-memory polymer that can be ceramicized obtained in Example 1 after being formed at 170°C, cooled to solidify, and left at room temperature for 48 hours to be fixed in shape;

[0029] Figure 3 is an XRD curve of a ceramic component obtained after sintering the ceramic shape memory polymer prepared in Example 1;

[0030] Figure 4 is a three-point bending curve of a ceramic component obtained after sintering the ceramic shape memory polymer prepared in Example 2;

[0031] Figure 5 is a three-point bending curve of a ceramic component obtained after sintering the ceramic shape memory polymer prepared in Example 3;

[0032] Figure 6 is the DMA curve of the shape memory polymer prepared in Comparative Example 1;

[0033] Figure 7 This is a physical picture of the shape memory polymer obtained in Example 1 after high temperature shaping at 170°C, cooling solidification and long-term storage at room temperature to fix the shape;

[0034] Figure 8 The phase separation phenomenon occurred in the preparation process of the shape memory polymer in Comparative Example 3. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] The present invention provides a ceramic shape memory polymer in a first aspect. The raw materials for preparing the ceramic shape memory polymer include: 4,4'-bismaleimidodiphenylmethane, 1,3-bis(4-aminophenoxy)benzene, bisaminopropyl-terminated polydimethylsiloxane and a curing agent.

[0037] The ceramic shape memory polymer prepared by the present invention using 4,4'-bismaleimidodiphenylmethane, 1,3-bis(4-aminophenoxy)benzene, bisaminopropyl-terminated polydimethylsiloxane and a curing agent as raw materials can be shape-edited during the heating process without the aid of ceramic-forming particles. Ceramic components can be obtained by ceramicization at a relatively low sintering temperature (as low as 800°C), which can meet the preparation requirements of ceramic components with complex structures, broaden the application scenarios of shape memory polymers, and is expected to be applied to the fields of smart solar panel deployment, smart hinges, smart pod poles, etc.

[0038] According to some preferred embodiments, the molar ratio of 4,4'-bismaleimidodiphenylmethane to 1,3-bis(4-aminophenoxy)benzene is 1:0.1 to 0.9 (for example, 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8 or 1:0.9);

[0039] The molar ratio of 4,4'-bismaleimidodiphenylmethane to bisaminopropyl-terminated polydimethylsiloxane is 1:0.1 to 0.9 (for example, 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8 or 1:0.9), preferably, the average molecular weight of the bisaminopropyl-terminated polydimethylsiloxane is 500 to 5000; and / or

[0040] The molar ratio of 4,4'-bismaleimidodiphenylmethane to the curing agent is 1:0.1-1 (for example, it can be 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9 or 1:1). Preferably, the curing agent is a curing agent with epoxy group double end-capping, and more preferably, the curing agent includes but is not limited to one or more of epoxy group double end-capped polydimethylsiloxane, bisphenol A diglycidyl ether, and 1,4-butanediol diglycidyl ether.

[0041] According to some preferred embodiments, the raw materials for preparing the ceramizable shape memory polymer further include at least one of room temperature curing silicone rubber and ceramic material.

[0042] The present invention introduces room temperature curing silicone rubber into the raw materials for preparation to form a shape memory polymer with an interpenetrating network, wherein the shape memory network (network formed by the prepolymer) and the silicone rubber network are interpenetrating, and during the ceramicization process, the shape memory network is pyrolyzed to generate small molecule gas escape, resulting in holes; the silicone rubber network pyrolyzes and escapes relatively less, shrinks in volume, and is relatively compact. The synergistic effect of the two can take into account the shape memory performance of the shape memory polymer before ceramicization and the mechanical bearing performance after ceramicization, and can improve the mechanical bearing performance of the ceramic component after sintering. The introduction of ceramic materials can achieve high temperature sintering, obtain reinforced ceramic components, and further improve the mechanical bearing performance of the ceramic component after sintering.

[0043] According to some preferred embodiments, the amount of the room temperature curing silicone rubber does not exceed 2 times the mass of 4,4'-bismaleimidodiphenylmethane, and preferably, the room temperature curing silicone rubber is an addition type silicone rubber. The present invention controls the amount of room temperature curing silicone rubber within the above range to ensure that a ceramic shape memory polymer with an interpenetrating network structure is obtained. The inventors have found that if the amount of room temperature curing silicone rubber is too large, phase separation will occur during the preparation of the ceramic shape memory polymer, and the ceramic shape memory polymer cannot be obtained.

[0044] According to some preferred embodiments, the amount of the ceramic material does not exceed 2 times the mass of 4,4'-bismaleimidodiphenylmethane. Preferably, the ceramic material includes but is not limited to one or more of zirconium boride, zirconium oxide, aluminum oxide, and silicon dioxide. The present invention controls the amount of the ceramic material within the above range to ensure that a ceramic shape memory polymer with excellent shape memory properties is obtained. The inventors have found that if the amount of the ceramic material is too large, the shape memory properties of the ceramic shape memory polymer will decrease, affecting the shaping and cutting properties.

[0045] In a second aspect, the present invention provides a method for preparing the ceramic shape memory polymer according to the first aspect, the preparation method comprising:

[0046] S1. mixing 4,4'-bismaleimidodiphenylmethane, 1,3-bis(4-aminophenoxy)benzene, bisaminopropyl-terminated polydimethylsiloxane and a solvent, and performing a prepolymerization reaction to obtain a prepolymer;

[0047] S2. mixing the prepolymer and the curing agent, removing the solvent to obtain a premix;

[0048] S3. Thermally curing the premix to obtain a ceramizable shape memory polymer.

[0049] The present invention prepolymerizes 4,4'-bismaleimidodiphenylmethane, 1,3-bis(4-aminophenoxy)benzene and bisaminopropyl-terminated polydimethylsiloxane to form a prepolymer, and then cures the prepolymer under the action of a curing agent to obtain a ceramic shape memory polymer.

[0050] According to some preferred embodiments, the prepolymerization reaction is carried out at 40 to 90° C. (for example, 40° C., 50° C., 60° C., 70° C., 80° C. or 90° C.) under condensation reflux for 18 to 36 hours;

[0051] The heat curing temperature is 50-200°C (for example, 50°C, 80°C, 100°C, 120°C, 150°C, 160°C, 180°C or 200°C), and the time is 3-10 hours; preferably, the heat curing is firstly kept at 40-60°C for 1-2 hours, then kept at 100-130°C for 1-4 hours, and finally kept at 200-220°C for 1-4 hours; and / or

[0052] The solvent is at least one of tetrahydrofuran, dichloromethane and acetone.

[0053] According to some preferred embodiments, the premix further comprises at least one of room temperature curing silicone rubber and ceramic material.

[0054] The present invention adds at least one of room temperature curing silicone rubber and ceramic material during the mixing process of prepolymer and curing agent, so as to further improve the performance of ceramic components after sintering. By introducing room temperature curing silicone rubber, a shape memory polymer with an interpenetrating network structure can be formed with the prepolymer under the action of the curing agent, and the introduction of ceramic material can improve the mechanical bearing performance of the ceramic component after the shape memory polymer is sintered, so as to obtain a reinforced ceramic component.

[0055] The present invention provides a ceramic component in a third aspect, which is obtained by sintering at a high temperature using the ceramicizable shape memory polymer described in the first aspect.

[0056] According to some preferred embodiments, the high temperature sintering temperature is 800-1600°C (for example, it can be 800°C, 900°C, 1000°C, 1100°C, 1200°C, 1300°C, 1400°C, 1500°C or 1600°C), and the sintering atmosphere is nitrogen, argon or air.

[0057] The ceramicizable shape memory polymer of the present invention can be ceramicized to obtain a ceramic component at a relatively low sintering temperature (as low as 800° C.), which is significantly lower than the sintering temperature (1300-1700° C.) of sintering ceramics using common ceramic fillers.

[0058] According to some preferred embodiments, the ceramizable shape memory polymer is temporarily shaped before the high temperature sintering.

[0059] When forming some ceramic components with complex structures, the shape memory polymer is first made into the shape of the component to be formed (a ceramic component precursor with an initial shape). In order to avoid some easily damaged parts (such as hollow structures, filamentary structures, etc.) from being damaged during storage and transportation, the temperature is usually raised to above the glass transition temperature, and an external force is applied to give the ceramic component precursor a temporary shape (for example, a flat plate shape). Then, the external force is maintained unchanged and the temperature is lowered to room temperature to fix the shape, and the external force is removed to obtain a ceramic component precursor with a temporary shape. During the sintering process, when the temperature reaches above the glass transition temperature, the ceramic component precursor with a temporary shape will automatically return to a ceramic component precursor with an initial shape. The temperature continues to rise and sintering forms a ceramic component with an initial shape.

[0060] In order to more clearly illustrate the technical solutions and advantages of the present invention, the present invention is further described below in conjunction with the examples. The present invention does not specifically limit the sources of the various reagents used in the examples and comparative examples, and they can be directly purchased or synthesized by themselves. The parts in the following examples and comparative examples of the present invention are parts by mass.

[0061] Example 1

[0062] A method for preparing a ceramic shape memory polymer, comprising:

[0063] S1. Mix 10 parts of 4,4'-bismaleimidodiphenylmethane, 5 parts of bisaminopropyl-terminated polydimethylsiloxane (average molecular weight 2000), 5 parts of 1,3-bis(4-aminophenoxy)benzene and 120 parts of dichloromethane, stir evenly until the solution is clear, place in an oil bath, condense and reflux at 50°C for 24 hours to obtain a prepolymer.

[0064] S2. Add 5 parts of bisphenol A diglycidyl ether to the above prepolymer, stir and mix, pour into a mold, leave at room temperature for 24 hours, remove the solvent, and obtain a premix.

[0065] S3. The premix is ​​placed in an oven and cured according to the following curing procedure: first, it is kept at 40°C for 4 hours, then at 120°C for 2 hours, and finally at 200°C for 1 hour. After demolding, a ceramic shape memory polymer is obtained.

[0066] A method for preparing a ceramic component, comprising:

[0067] The ceramic shape memory polymer was placed on a heating table and heated to 180° C. to give the ceramic shape memory polymer a temporary shape. It was then placed in a tubular furnace and sintered at 800° C. for 1 hour in a nitrogen atmosphere to obtain a ceramic component.

[0068] Depend on Figure 1 It can be seen that the glass transition temperature Tg of the ceramic shape memory polymer prepared in this embodiment is 153.42° C. It should be noted that the horizontal axis in the figure represents temperature, the left vertical axis represents storage modulus, and the right vertical axis represents loss factor.

[0069] Depend on Figure 2 It can be seen that the ceramicizable shape memory polymer (initial shape is sheet-like) prepared in this embodiment can basically maintain its shape after being formed at a high temperature of 170° C., cooled and solidified, and then placed at room temperature for 48 hours.

[0070] Depend on Figure 3 It can be seen that the XRD curve of the ceramic component obtained after sintering the ceramicizable shape memory polymer prepared in this embodiment shows two peaks of free carbon and no other crystalline state, which proves that the amorphous SiOC ceramic is obtained.

[0071] Example 2

[0072] A method for preparing a ceramic shape memory polymer, comprising:

[0073] S1. Mix 10 parts of 4,4'-bismaleimidodiphenylmethane, 8 parts of bisaminopropyl-terminated polydimethylsiloxane (average molecular weight 2000), 2 parts of 1,3-di(4-aminophenoxy)benzene and 120 parts of dichloromethane, stir evenly until the solution is clear, place in an oil bath, condense and reflux at 50°C for 24 hours to obtain a prepolymer.

[0074] S2. Add 5 parts of resorcinol diglycidyl ether to the above prepolymer, stir and mix, pour into a mold, leave at room temperature for 24 hours, remove the solvent, and obtain a premix.

[0075] S3. The premix is ​​placed in an oven and cured according to the following curing procedure: first, it is kept at 40°C for 4 hours, then at 120°C for 2 hours, and finally at 200°C for 1 hour. After demolding, a ceramic shape memory polymer is obtained.

[0076] A method for preparing a ceramic component, comprising:

[0077] The ceramic shape memory polymer was placed on a heating table and heated to 180° C. to give the ceramic shape memory polymer a temporary shape. It was then placed in a tubular furnace and sintered at 800° C. for 1 hour in a nitrogen atmosphere to obtain a ceramic component.

[0078] Example 3

[0079] S1. Mix 10 parts of 4,4'-bismaleimidodiphenylmethane, 8 parts of bisaminopropyl-terminated polydimethylsiloxane (average molecular weight 2000), 2 parts of 1,3-di(4-aminophenoxy)benzene and 120 parts of dichloromethane, stir evenly until the solution is clear, place in an oil bath, condense and reflux at 50°C for 24 hours to obtain a prepolymer.

[0080] S2. Add 5 parts of resorcinol diglycidyl ether and 15 parts of zirconium boride ceramic powder to the above prepolymer, stir and mix, pour into a mold, leave at room temperature for 24 hours, remove the solvent, and obtain a premix.

[0081] S3. The premix is ​​placed in an oven and cured according to the following curing procedure: first, it is kept at 40°C for 4 hours, then at 120°C for 2 hours, and finally at 200°C for 1 hour. After demolding, a ceramic shape memory polymer is obtained.

[0082] A method for preparing a ceramic component, comprising:

[0083] The ceramic shape memory polymer was placed on a heating table and heated to 180°C to give the ceramic shape memory polymer a temporary shape. It was then placed in a tubular furnace and sintered at 800°C for 1 hour and 1300°C for 1 hour in a nitrogen atmosphere to obtain a ceramic component.

[0084] Depend on Figure 4-5 It can be seen that the ceramic component ( Figure 4 ) compared to the ceramic component ( Figure 5 ) has higher flexural strength and flexural modulus. It can be seen that the introduction of ceramic powder can improve the flexural strength and flexural modulus of ceramic components.

[0085] In addition, compared with the ceramic component obtained by sintering the ceramic shape memory polymer prepared in Example 2, the ceramic component obtained by sintering the ceramic shape memory polymer prepared in Example 3 has better mechanical properties.

[0086] Example 4

[0087] S1. Mix 10 parts of 4,4'-bismaleimidodiphenylmethane, 5 parts of bisaminopropyl-terminated polydimethylsiloxane (average molecular weight 2000), 5 parts of 1,3-bis(4-aminophenoxy)benzene and 120 parts of dichloromethane, stir evenly until the solution is clear, place in an oil bath, condense and reflux at 50°C for 24 hours to obtain a prepolymer.

[0088] S2. Add 5 parts of bisphenol A diglycidyl ether and 15 parts of zirconium boride ceramic powder to the above prepolymer, stir and mix, pour into a mold, leave at room temperature for 24 hours, remove the solvent, and obtain a premix.

[0089] S3. The premix is ​​placed in an oven and cured according to the following curing procedure: first, it is kept at 40°C for 4 hours, then at 120°C for 2 hours, and finally at 200°C for 1 hour. After demolding, a ceramic shape memory polymer is obtained.

[0090] A method for preparing a ceramic component, comprising:

[0091] The ceramic shape memory polymer was placed on a heating table and heated to 180°C to give the ceramic shape memory polymer a temporary shape. It was then placed in a tubular furnace and sintered at 800°C for 1 hour and then at 1300°C for 1 hour in a nitrogen atmosphere to obtain a ceramic component.

[0092] Compared with Example 1, the ceramic component obtained after sintering the shape memory polymer prepared by adding ceramic powder in this example has better mechanical properties.

[0093] Example 5

[0094] S1. Mix 10 parts of 4,4'-bismaleimidodiphenylmethane, 5 parts of bisaminopropyl-terminated polydimethylsiloxane (average molecular weight 2000), 5 parts of 1,3-bis(4-aminophenoxy)benzene and 120 parts of dichloromethane, stir evenly until the solution is clear, place in an oil bath, condense and reflux at 50°C for 24 hours to obtain a prepolymer.

[0095] S2. Add 5 parts of bisphenol A diglycidyl ether and 15 parts of room temperature curing silicone rubber to the above prepolymer, stir and mix, pour into a mold, leave at room temperature for 24 hours, remove the solvent, and obtain a premix.

[0096] S3. The premix is ​​placed in an oven and cured according to the following curing procedure: first, it is kept at 40°C for 4 hours, then at 120°C for 2 hours, and finally at 200°C for 1 hour. After demolding, a ceramic shape memory polymer is obtained.

[0097] A method for preparing a ceramic component, comprising:

[0098] The ceramic shape memory polymer was placed on a heating table and heated to 180° C. to give the ceramic shape memory polymer a temporary shape. It was then placed in a tubular furnace and sintered at 800° C. for 1 hour in a nitrogen atmosphere to obtain a ceramic component.

[0099] In this embodiment, a ceramic shape memory polymer with an interpenetrating network structure is prepared by introducing room temperature curing silicone rubber. Compared with Example 1, the ceramic shape memory polymer has a higher content of silicon oxygen segments, and the ceramic part obtained after sintering has better mechanical bearing properties.

[0100] Example 6

[0101] S1. Add 120 parts of dichloromethane as solvent to 10 parts of 4,4'-bismaleimidodiphenylmethane, 5 parts of bisaminopropyl-terminated polydimethylsiloxane (average molecular weight 2000), and 5 parts of 1,3-bis(4-aminophenoxy)benzene, stir evenly until the solution is clear, place in an oil bath, and condense and reflux at 50°C for 24 hours to obtain a prepolymer.

[0102] S2. Add 5 parts of bisphenol A diglycidyl ether, 15 parts of room temperature curing silicone rubber, and 15 parts of zirconium boride ceramic powder to the above prepolymer, stir and mix, pour into a mold, leave at room temperature for 24 hours, remove the solvent, and obtain a premix.

[0103] S3. The premix is ​​placed in an oven and cured according to the following curing procedure: first, it is kept at 40°C for 4 hours, then at 120°C for 2 hours, and finally at 200°C for 1 hour. After demolding, a ceramic shape memory polymer is obtained.

[0104] A method for preparing a ceramic component, comprising:

[0105] The ceramic shape memory polymer was placed on a heating table and heated to 180°C to give the ceramic shape memory polymer a temporary shape. It was then placed in a tubular furnace and sintered at 800°C for 1 hour and then at 1300°C for 1 hour in a nitrogen atmosphere to obtain a ceramic component.

[0106] In this embodiment, the room temperature curing silicone rubber is introduced to form an interpenetrating network structure, and ceramic powder is added to play a reinforcing role. The reinforced ceramic component obtained after sintering. Compared with Example 5, the ceramic component obtained in this embodiment has better mechanical bearing performance.

[0107] Comparative Example 1:

[0108] The method is basically the same as Example 1, except that: in step S1, 1,3-di(4-aminophenoxy)benzene is not added, and the amount of bis-aminopropyl-terminated polydimethylsiloxane used is 10 parts.

[0109] like Figure 6 As shown, the content of flexible silicon-oxygen segments in the raw materials is too much, which makes the peak width of the loss factor larger, resulting in a decrease in shape memory performance at room temperature. It should be noted that the horizontal axis in the figure represents temperature, the left vertical axis represents storage modulus, and the right vertical axis represents loss factor.

[0110] like Figure 7 As shown, the shape memory polymer (initial shape is sheet-like) prepared in this comparative example gradually recovered to its initial shape after being shaped at 170°C, cooled and solidified, and then placed at room temperature for 48 hours.

[0111] Comparative Example 2

[0112] The method is basically the same as Example 1, except that in step S1, no bis-aminopropyl-terminated polydimethylsiloxane is added, and the amount of 1,3-di(4-aminophenoxy)benzene used is 10 parts.

[0113] The component obtained after sintering the shape memory polymer prepared in this comparative example does not contain silicon element, and its main component is free carbon, so it cannot be called a ceramic component.

[0114] Comparative Example 3

[0115] The method is basically the same as Example 5, except that in step S2, the amount of room temperature curing silicone rubber is 55 parts.

[0116] In this comparative example, due to the excessive amount of silicone rubber added in the raw materials, phase separation occurred during the mixing process, showing a macroscopic sea island structure (such as Figure 8 As shown), it is impossible to obtain a ceramic shape memory polymer.

[0117] Comparative Example 4

[0118] It is basically the same as Example 4, except that in step S2, the amount of ceramic powder zirconium boride is 40 parts.

[0119] In this comparative example, since the amount of ceramic powder added in the raw material is too large, the continuity of the matrix resin is affected, resulting in poor shape memory performance of the composite material, which affects the shaping and cutting performance.

[0120] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A ceramic shape memory polymer, characterized in that: The raw materials for preparing the ceramicizable shape memory polymer include: 4,4'-bismaleimidodiphenylmethane, 1,3-bis(4-aminophenoxy)benzene, bisaminopropyl-terminated polydimethylsiloxane and a curing agent.

2. The ceramicizable shape memory polymer according to claim 1, characterized in that: The molar ratio of 4,4'-bismaleimidodiphenylmethane to 1,3-bis(4-aminophenoxy)benzene is 1:0.1-0.9; The molar ratio of 4,4'-bismaleimidodiphenylmethane to bisaminopropyl-terminated polydimethylsiloxane is 1:0.1-0.9, and preferably, the average molecular weight of bisaminopropyl-terminated polydimethylsiloxane is 500-5000; and / or The molar ratio of 4,4'-bismaleimidodiphenylmethane to the curing agent is 1:0.1-1. Preferably, the curing agent is a curing agent with epoxy group double end-capping. More preferably, the curing agent includes but is not limited to one or more of epoxy group double end-capped polydimethylsiloxane, bisphenol A diglycidyl ether, and 1,4-butanediol diglycidyl ether.

3. The ceramicizable shape memory polymer according to claim 1 or 2, characterized in that: The raw materials for preparing the ceramicizable shape memory polymer also include at least one of room temperature curing silicone rubber and ceramic materials.

4. The ceramizable shape memory polymer according to claim 3, characterized in that: The amount of the room temperature curing silicone rubber is no more than twice the mass of 4,4'-bismaleimidodiphenylmethane. Preferably, the room temperature curing silicone rubber is an addition type silicone rubber; and / or The amount of the ceramic material used is no more than twice the mass of 4,4'-bismaleimidodiphenylmethane. Preferably, the ceramic material includes but is not limited to one or more of zirconium boride, zirconium oxide, aluminum oxide, and silicon dioxide.

5. A method for preparing a ceramizable shape memory polymer according to any one of claims 1 to 4, characterized in that: The preparation method comprises: S1. mixing 4,4'-bismaleimidodiphenylmethane, 1,3-bis(4-aminophenoxy)benzene, bisaminopropyl-terminated polydimethylsiloxane and a solvent, and performing a prepolymerization reaction to obtain a prepolymer; S2. mixing the prepolymer and the curing agent, removing the solvent to obtain a premix; S3. Thermally curing the premix to obtain a ceramizable shape memory polymer.

6. The preparation method according to claim 5, characterized in that: The prepolymerization reaction is carried out by condensing and refluxing at 40 to 90° C. for 18 to 36 hours; The temperature of the thermal curing is 50-200°C and the time is 3-10 hours; preferably, the thermal curing is firstly kept at 40-60°C for 1-2 hours, then kept at 100-130°C for 1-4 hours, and finally kept at 200-220°C for 1-4 hours; and / or The solvent is at least one of tetrahydrofuran, dichloromethane and acetone.

7. The preparation method according to claim 5, characterized in that: The premix further comprises at least one of room temperature curing silicone rubber and ceramic material.

8. A ceramic component, characterized in that: The ceramic shape memory polymer according to any one of claims 1 to 4 is obtained by high temperature sintering.

9. The ceramic component according to claim 8, characterized in that The temperature of the high-temperature sintering is 800-1600° C., and the sintering atmosphere is nitrogen, argon or air.

10. The ceramic component according to claim 8, characterized in that Before the high-temperature sintering, the method further includes temporarily shaping the ceramizable shape memory polymer.

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