A ablative-resistant hybrid resin containing a covalent-ionic bicontinuous network, and methods of making and using the same

Abstract

The application belongs to the field of thermal protection materials, and particularly relates to a covalent-ionic bicontinuous network-containing ablative-resistant hybrid resin as well as a preparation method and application thereof. The application introduces organic molecule functionalized inorganic ion oligomers into boron phenolic resin to obtain an organic-inorganic hybrid resin; synchronous cross-linking and polymerization of thermosetting network and inorganic ion network in the hybrid resin is realized for the first time to obtain a covalent-ionic bicontinuous network. The hybrid resin prepared by the application has excellent mechanical properties and ablative resistance, and has wide application prospects in the fields of structural materials, composite materials, thermal protection materials and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of thermal protection materials, and particularly relates to a kind of ablation-resistant hybrid resin containing covalent-ion double continuous network and its preparation method and use. BACKGROUND

[0002] Resin-based ablation thermal protection materials have high heat protection efficiency and reliable work, and are the most widely used heat protection materials and structures at present, and among them, phenolic resin-based composites play a very important role in aircraft thermal protection composites. Phenolic resin is often used as the matrix of ablation-resistant composite coating due to its simple molding process, good heat resistance, high mechanical strength and outstanding instantaneous high-temperature ablation resistance. The PhenCarb series of lightweight carbonized ablation materials prepared by NASA in the United States with phenolic resin as the matrix have low surface ablation rate and thick carbon layer after ablation. The phenolic impregnated carbon ablation material (PICA) prepared by the Ames Center in the United States with phenolic resin as the matrix has been successfully applied to the thermal protection system of the Stardust return capsule.

[0003] However, the new generation of high-speed aircraft needs to fly for a long time in an oxygen environment, and the traditional phenolic resin has been difficult to meet the requirements of thermal protection due to its low residual carbon rate and poor oxidation resistance, and it is urgent to develop a new type of high-performance high-temperature oxidation-resistant phenolic resin. The organic-inorganic hybrid structure formed by introducing inorganic components into the resin structure can effectively improve the long-time oxidation resistance of the resin. Traditional organic-inorganic hybrid resins are usually prepared by the following three methods: (1) adding inorganic fillers; (2) bonding with inorganic ions through ionic bonds or coordination bonds; (3) copolymerization or graft modification with inorganic element-containing monomers represented by silane through covalent bonds. For organic-inorganic hybrid resins, reducing the size of inorganic units can effectively improve the interaction between the two phases and reduce or eliminate the boundary between the organic phase and the inorganic phase in the hybrid material, effectively improving the comprehensive performance of the hybrid resin. However, the existing molecular structure design of organic-inorganic hybrid resins has the problems of limited types of introduced inorganic elements, difficulty in combining high hetero-element content with excellent two-phase interface, and difficulty in playing the synergistic reinforcement mechanism of inorganic oxidation-resistant ceramics and high-strength graphitized carbon layer during high-temperature oxidation resistance.

[0004] Based on the existing problems of organic-inorganic hybrid resins, it is urgent to design an organic-inorganic hybrid resin that can eliminate interface defects and also exhibit excellent heat resistance and ablation resistance during high-temperature oxidation resistance. SUMMARY

[0005] In view of the problems of the prior art, the present application provides a kind of ablation-resistant hybrid resin containing covalent-ion double continuous network and its preparation method and use.

[0006] A hybrid resin with ablation resistance is made by curing the following raw materials in parts by weight:

[0007] a salt containing metal cation 10-30 parts,

[0008] an anion donor 4-10 parts,

[0009] an end-capping agent 150-900 parts,

[0010] a monomer compound 5-30 parts,

[0011] a modified phenolic resin 2-120 parts.

[0012] The monomer compound is a compound having a carboxyl group at one end and a group capable of reacting with a phenolic resin at the other end.

[0013] Preferably, the group capable of reacting with a phenolic resin is at least one selected from an epoxy group, a maleimide group, a cyanate group, an isocyanate group, an amino group, a carboxyl group, a hydroxyl group, an aldehyde group, a thiol group, and a boronic acid group.

[0014] Preferably, it is made by curing the following raw materials in parts by weight:

[0015] a salt containing metal cation 12 parts,

[0016] an anion donor 8 parts,

[0017] an end-capping agent 166 parts,

[0018] a monomer compound 7 parts,

[0019] a modified phenolic resin 30 parts.

[0020] Preferably, the metal cation is at least one selected from a calcium ion, a copper ion, a manganese ion, a zirconium ion, a hafnium ion, a magnesium ion, and an iron ion; and the anion of the salt containing metal cation is at least one selected from a chloride ion, a carbonate ion, a sulfate ion, a nitrate ion, and a phosphate ion.

[0021] Preferably, the monomer compound is at least one selected from a phenylboronic acid compound, a hydroxybenzoic acid compound, a hydroxyphenylacetic acid compound, a hydroxyphenylpropionic acid compound, a mercaptoacetic acid compound, and a mercaptobenzoic acid compound.

[0022] Preferably, the modified phenolic resin is any one selected from a boron phenolic resin, an epoxy-modified phenolic resin, a polyamide-modified phenolic resin, a silicone-modified phenolic resin, a dicyandiamide-modified phenolic resin, a polyvinyl acetal-modified phenolic resin, and a diphenyl ether formaldehyde resin.

[0023] Preferably, the acid ion donor is selected from at least one of phosphoric acid, CO2, sulfuric acid, and nitric acid; and / or the capping agent is selected from triethylamine.

[0024] The present invention also provides a method for preparing the hybrid resin having ablation resistance, comprising the following steps: Step 1, preparing an inorganic ion oligomer using a salt containing a metal cation, a capping agent, and an acid radical ion donor;

[0025] Step 2, reacting the monomer compound with the inorganic ion oligomer obtained in step 1 to obtain an organic functionalized inorganic ion oligomer;

[0026] Step 3: reacting the modified phenolic resin with the organic functionalized inorganic ion oligomer obtained in step 2 to obtain a hybrid resin with ablation resistance.

[0027] Preferably, in step 1, the preparation method of the inorganic ion oligomer is as follows: step 1.1, reacting a salt containing a metal cation with a complexing agent to obtain solution A;

[0028] Step 1.2, reacting the acid ion donor with the complexing agent to obtain solution B;

[0029] Step 1.3, after solution A reacts with solution B, a dispersion 1 of inorganic ion oligomers is obtained;

[0030] Step 1.4, the inorganic ion oligomer dispersion 1 is centrifuged to obtain an inorganic ion oligomer gel, which is then washed and dispersed to obtain;

[0031] And / or, in step 2, the preparation method of the organic functionalized inorganic ion oligomer is:

[0032] Step 2.1, reacting the monomer compound with the inorganic ion oligomer to obtain a dispersion 1 of the organic functionalized inorganic ion oligomer;

[0033] Step 2.2, centrifuging the organic functionalized inorganic ion oligomer dispersion 1 to obtain an organic functionalized inorganic ion oligomer gel, and then washing and dispersing the gel to obtain;

[0034] And / or, in step 3, the preparation method of the hybrid resin is: reacting an organic functionalized inorganic ion oligomer with a modified phenolic resin, obtaining a hybrid resin gel by centrifugation, washing and drying to obtain a hybrid resin powder, and then curing to obtain the hybrid resin.

[0035] Preferably, in steps 1.1 and 1.2, the reaction solvent is anhydrous ethanol; in step 1.3, the reaction time is 6-24 hours; in step 1.4, the centrifugal speed is 5000-12000 rpm, the centrifugal time is 1-10 minutes, the washing reagent is ethanol, and the dispersant is anhydrous ethanol.

[0036] Preferably, in step 2.1, the solvent of the monomer compound is anhydrous methanol, and the reaction time is 6-24 hours; in step 2.2, the centrifugal speed is 5000-12000 rpm, the centrifugal time is 1-10 minutes, the washing reagent is ethanol, and the dispersant is anhydrous ethanol.

[0037] Preferably, in step 3, the reaction temperature is 70-90°C, the reaction time is 4-8h under inert atmosphere; the centrifugal speed is 5000-12000rpm, and the centrifugal time is 1-10min; the washing reagent is ethanol; the drying conditions are 70-90°C, -0.08-0.1MPa; the curing conditions are 100-120°C for 20-40min, and the pressure is maintained at 25-35MPa; the temperature is increased from 100-120°C to 130-150°C at a rate of 5-20°C / min; the temperature is maintained at 130-150°C for 20-40min. 20-40min, maintain the pressure at 25-35MPa; heat from 130-150℃ to 170-190℃, heat at a rate of 5-20℃ / min, maintain the pressure at 25-35MPa; keep at 170-190℃ for 1-3h, maintain the pressure at 25-35MPa; heat from 170-190℃ to 190-210℃, heat at a rate of 5-20℃ / min, maintain the pressure at 25-35MPa; keep at 190-210℃ for 0.5-1.5h, maintain the pressure at 25-35MPa; finally, maintain the pressure at 25-35MPa.

[0038] The present invention also provides use of the hybrid resin having ablation resistance in the preparation and / or as ablation resistant material.

[0039] The molecular precision mentioned in the present invention means that the molecular formula of the functionalized inorganic ion oligomer is clear.

[0040] This invention introduces inorganic ion oligomers functionalized with molecularly precise organic groups into a boron phenolic resin, achieving for the first time the simultaneous initiation of crosslinking and polymerization of a thermosetting network and an inorganic ion network in a hybrid resin, resulting in a covalent-ionic bicontinuous network with a continuous structure from the macro to micro scale. This method for constructing a covalent-ionic bicontinuous network between functionalized inorganic ion oligomers and phenolic resin enables the precise control of other organic-inorganic thermosetting hybrid resins. Furthermore, the hybrid resin of this invention exhibits excellent high-temperature oxidation resistance and ablation resistance, and has broad application prospects in the field of thermal protection materials.

[0041] Obviously, based on the above contents of the present invention, according to common technical knowledge and customary means in this field, without departing from the above basic technical ideas of the present invention, other various forms of modifications, replacements or changes can be made.

[0042] The following further describes the above content of the present invention in detail through specific embodiments in the form of examples. However, this should not be construed as limiting the scope of the above subject matter of the present invention to the following examples. All technologies implemented based on the above content of the present invention fall within the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 Molecular structure characterization of functionalized inorganic ion oligomers. (a) Schematic diagram of the synthesis and structure of 3-BAPO; (b) IR spectrum of 3-BAPO; (c) Elemental analysis of 3-BAPO using ICP-OES.

[0044] Figure 2 Characterization of the supramolecular interaction between functionalized inorganic ion oligomers and boron phenolic resin in 3-BRPO. (a) FTIR spectra; (b) Raman spectra; (c) X-ray photoelectron spectroscopy (XPS).

[0045] Figure 3 is the relative content of inorganic elements in 3-BRPO hybrid resin powder (before curing).

[0046] Figure 4 Characterization of the cross-linked network structure of 3-BRPO hybrid resin before and after curing.

[0047] Figure 5 This is the optical morphology of 3-BRPO hybrid resin.

[0048] Figure 6 It is a dual-continuous phase structure of 3-BRPO hybrid resin.

[0049] Figure 7 Small-angle X-ray scattering (SAXS) characterization of 3-BRPO hybrid resin.

[0050] Figure 8 Thermogravimetric instrument was used to characterize the heat resistance of hybrid resin.

[0051] Figure 9 Characterization of the static ablation performance of the hybrid resin using a tube furnace. (a) Photos of 3-BPROa before and after static ablation in a tube furnace; (b) Photos of BPR before and after static ablation in a tube furnace; (c) XRD pattern of the carbonized ceramic product after static ablation of 3-BRPOa.

[0052] Figure 10 The dynamic ablation performance of 3-BPRO hybrid resin in oxygen-rich atmosphere was characterized for plasma ablation machine.

[0053] Figure 11 Nanoindentation instrument was used to characterize the mechanical properties of 3-BPRO hybrid resin. DETAILED DESCRIPTION

[0054] In the following examples and experimental examples, reagents and raw materials not specifically described are all commercially available.

[0055] Example 1 Preparation of 3-carboxyphenylboronic acid functionalized calcium phosphate inorganic ion oligomer boron phenolic resin (3-BRPO)

[0056] 1. Preparation of calcium phosphate inorganic ion oligomers (CPO)

[0057] 80 mmol of calcium chloride dihydrate was dissolved in 1 L of anhydrous ethanol. 800 mmol of triethylamine was added and stirred for 10 minutes to obtain Solution A. 80 mmol of phosphoric acid and 800 mmol of triethylamine were dispersed in 1 L of anhydrous ethanol to obtain Solution B. Solution B was added dropwise to Solution A. After the addition was complete, the reaction was continued for 24 hours to obtain CPO ethanol dispersion 1. CPO gel was obtained by high-speed centrifugation (10,000 rpm, 2 minutes). The CPO gel was rinsed with ethanol several times to remove any residual triethylamine. The CPO gel was then redispersed in 1 L of anhydrous ethanol to obtain CPO ethanol dispersion 2.

[0058] 2. Preparation of 3-carboxyphenylboronic acid functionalized calcium phosphate inorganic ion oligomer (3-BAPO)

[0059] 42 mmol of 3-carboxyphenylboronic acid (3-CPBA) was weighed and dissolved in 800 mL of anhydrous methanol. The CPO ethanol dispersion 2 obtained above was added dropwise to the methanol solution of 3-CPBA. After the addition was complete, the reaction was continued for 24 hours to obtain 3-BAPO ethanol dispersion 1. 3-BAPO gel was obtained by high-speed centrifugation (10,000 rpm, 2 min). The 3-BAPO gel was washed with ethanol several times to remove residual 3-CPBA. The above 3-BAPO gel was redispersed in 1 L of anhydrous ethanol to obtain 3-BAPO ethanol dispersion 2.

[0060] 3. Preparation of 3-BAPO / boron phenolic resin hybrid material (3-BRPO)

[0061] Boron phenolic resin (THC-400, from Shaanxi Taihang Fire Resistant Company) and 200g of ethanol were added to a flask and stirred at room temperature until the boron phenolic resin (BPR) was completely dissolved. The temperature was then raised to 80°C and 3-BAPO ethanol dispersion 2 was added dropwise through a constant pressure dropping funnel under argon. After the addition was complete, the reaction was continued at 80°C for 6 hours. After the reaction, 3-BRPO gel was obtained by high-speed centrifugation (10,000 rpm, 2 minutes). The 3-BRPO gel was rinsed with ethanol several times to remove any residual BPR, and the solvent was then removed in a vacuum oven (80°C, -0.1 MPa) to obtain 3-BRPO powder. Curing process: 110°C for 30 minutes, maintaining pressure at 30 MPa; heating from 110°C to 140°C at a heating rate of 5°C / min; heating at 140°C for 30 minutes, maintaining pressure at 30 MPa; heating from 140°C to 180°C at a heating rate of 5°C / min, maintaining pressure at 30 MPa; heating at 180°C for 2 hours, maintaining pressure at 30 MPa; heating from 180°C to 200°C at a heating rate of 5°C / min, maintaining pressure at 30 MPa; heating at 200°C for 1 hour, maintaining pressure at 30 MPa; finally, maintaining pressure at 30 MPa and naturally cooling to room temperature to obtain the product. The amounts of boron phenolic resin (BPR) used are shown in Table 1, and 3-BRPOa, 3-BRPOb, and 3-BRPOc were prepared, respectively.

[0062] Table 1

[0063] name BPR Anhydrous ethanol 3-BRPOa 60g 200g 3-BRPOb 30g 200g 3-BRPOc 5g 200g

[0064] The following is the preparation method of the control sample.

[0065] Comparative Example 1

[0066] 1. Calcium phosphate (Ca3(PO4)2)

[0067] The sample is calcium phosphate inorganic ion oligomer (CPO), which was prepared according to step 1 of Example 1.

[0068] 2. BPR

[0069] This sample is boron phenolic resin.

[0070] 3. 3-BAPO

[0071] The sample was prepared according to step 2 of Example 1.

[0072] 4. 3-CPBA

[0073] This sample is 3-carboxyphenylboronic acid.

[0074] The technical solution of the present invention is further illustrated by experiments below.

[0075] Experimental Example 1: Molecular Structure Characterization of Functionalized Inorganic Ionic Oligomer (3-BAPO)

[0076] The 3-BAPO, 3-CPBA and Ca3(PO4)2 in this experimental example were prepared according to the method of Comparative Example 1.

[0077] 1. Experimental Methods

[0078] The molecular structure of 3-BAPO molecules was characterized by infrared spectroscopy and ICP-OES plasma spectrometry.

[0079] 2. Experimental Results

[0080] like Figure 1 (a) shows the synthesis and structural diagram of 3-BAPO. Calcium phosphate inorganic ion oligomer (CPO) and 3-carboxyphenylboronic acid (3-CPBA) are reacted to obtain 3-carboxyphenylboronic acid functionalized calcium phosphate inorganic ion oligomer (3-BAPO). Figure 1 (b) In the infrared spectrum, the 3-CPBA line can be found at 1686 cm -1 The C=O peak was observed at 1545 cm-1, and as the acid-base neutralization reaction of 3-CPBA and CPO proceeded, this peak red-shifted to 1545 cm-1. -1 The changes in FTIR spectra confirmed that an ionic bond was formed between the carboxyl group in 3-CPBA and the phosphoric acid in CPO, indicating that there was a strong chemical interaction between the two. Figure 1 As shown in (c), ICP-OES confirmed that the average Ca / B and P / B molar ratios were approximately 5:1 and 3:1, respectively, supporting the molecular formula of 3-BAPO as 3-CPBA3Ca3PO4(Ca3(PO4)2)4.

[0081] Experimental Example 2: Characterization of supramolecular interactions between functionalized inorganic ion oligomers and boron phenolic resin in 3-BRPO

[0082] In this experimental example, 3-BRPO b, BPR, 3-BAPO, 3-CPBA, and Ca3(PO4)2 were prepared according to the methods in Example 1 and Control Example 1.

[0083] 1. Experimental Methods

[0084] The supramolecular interactions between functionalized inorganic ion oligomers and boron phenolic resin in 3-BRPO hybrid resin powder (before curing) were characterized by infrared spectroscopy, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS).

[0085] 2. Experimental Results

[0086] Figure 2 In infrared spectrum, 1380 cm -1654cm -1 The BO peak intensity at 1200 cm-1 is significantly reduced, indicating that 3-BAPO coordinates with B and O in BPR. In addition, the BO peak at 1200 cm-1 is also observed. -1 The Ph-OH peak at α shifts toward higher wavenumbers, indicating that the hydroxyl groups in BPR form hydrogen bonds with the phosphate groups in calcium phosphate oligomers.

[0087] Figure 2 b The PO peak in the Raman spectrum broadens and shifts, indicating that the hydroxyl groups in BPR form hydrogen bonds with calcium phosphate.

[0088] Figure 2 In the cXPSCa2p fine spectrum, due to Ca 2+ The binding energy between the calcium phosphate oligomer and the carboxylate group is higher, and the Ca2p peak moves towards the direction of high binding energy after functionalization with 3-carboxyphenylboronic acid, indicating that the organic functionalization of the calcium phosphate oligomer has been successfully achieved through acid-base neutralization reaction. In addition, the Ca2p peak of the hybrid resin powder further moves towards the direction of high binding energy, and the orbital electron density of calcium changes, indicating that supramolecular interactions are generated between the functionalized inorganic ion oligomer and the boron phenolic resin, increasing the Ca 2+ Binding energy with the surrounding chemical environment.

[0089] Figure 2 In the dXPS O1s fine spectrum, the phosphate peak position in the hybrid resin powder and the boron phenolic resin peak position were significantly shifted compared with 3-BAPO and BPR, moving toward high binding energy and low binding energy directions, respectively, indicating that the oxygen-containing structures in the two structures produced supramolecular interactions with each other.

[0090] Figure 2 In the eXPS B1s fine spectrum, characteristic peaks of boron-oxygen coordination can be observed in the hybrid resin powder. 3-BAPO and BPR contain both B and O elements, so the above peaks indicate that the B and O elements in the inorganic and organic structures of the hybrid resin are coordinated with each other.

[0091] Experimental Example 3: Characterization of element content in 3-BRPO hybrid resin

[0092] In this experimental example, 3-BRPO a, 3-BRPO b, and 3-BRPO c were prepared according to the method in Example 1.

[0093] 1. Experimental Methods

[0094] The relative content of inorganic elements in the hybrid resin powder (before curing) was characterized by ICP-OES plasma spectrometer.

[0095] 2. Experimental Results

[0096] like Figure 3As shown, the results show that by regulating the concentration of the boron phenolic resin ethanol solution, a hybrid resin with a total inorganic element content between 13.5 and 25.9 wt.% was successfully prepared.

[0097] Experimental Example 4: Characterization of the cross-linked network structure of 3-BRPO hybrid resin before and after curing

[0098] In this experimental example, 3-BRPO b(Cured) is the cured 3-BRPO hybrid resin, and 3-BRPO b is the 3-BRPO hybrid resin before curing; BPR(Cured) is the cured boron phenolic resin, and BPR is the boron phenolic resin before curing. All of them were prepared according to the methods in Example 1 and Comparative Example 1.

[0099] 1. Experimental Methods

[0100] X-ray diffractometer (XRD) was used to characterize whether the high-pressure gradient temperature process could simultaneously stimulate the curing of boron phenolic resin and the inorganic ion polymerization of amorphous calcium phosphate network in the hybrid resin.

[0101] 2. Experimental Results

[0102] like Figure 4 As shown, the boron phenolic resin exhibits a blunted amorphous diffraction peak at approximately 20°, corresponding to the amorphous resin network. This peak shifts toward lower angles as curing progresses, indicating a more disordered cross-linked network after curing. The XRD spectrum of the hybrid resin 3-BRPOb exhibits amorphous diffraction peaks corresponding to both the amorphous resin network (~20°) and the amorphous calcium phosphate network (~30°). Consistent with the results observed for the boron phenolic resin, the amorphous diffraction peak of the hybrid resin network shifts toward lower angles after curing, indicating successful activation of the crosslinks in the organic portion of the hybrid resin. The amorphous diffraction peak corresponding to the amorphous calcium phosphate network shifts toward higher angles after curing, indicating an increase in the Ca-O coordination number in the system. This demonstrates that the high-pressure gradient temperature process can be used to form an amorphous calcium phosphate network through inorganic ion polymerization in the hybrid resin.

[0103] In summary, XRD proved that the high-pressure gradient temperature rising process can simultaneously stimulate the curing of boron phenolic resin and the inorganic ion polymerization of amorphous calcium phosphate network in the hybrid resin.

[0104] Experimental Example 5: Characterization of the organic-inorganic bicontinuous network after curing of 3-BRPO hybrid resin

[0105] In this experimental example, 3-BRPO a, 3-BRPO b, and 3-BRPO c were prepared according to the method in Example 1.

[0106] 1. Experimental Methods

[0107] The bicontinuous network of the hybrid resin after curing was characterized by optical morphology, high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and small-angle X-ray scattering (SAXS).

[0108] 2. Experimental Results

[0109] like Figure 5 As shown, all hybrid resins do not scatter visible light and exhibit a uniform and transparent macroscopic morphology, indicating that the obtained resin castings are all nanoscale bicontinuous materials.

[0110] like Figure 6 As shown in the figure, a continuous calcium-containing microphase separation structure (light-colored area) can be clearly observed, and this structure is interspersed with the uniform permeation phase of BPR (dark-colored area) to form a bicontinuous phase structure.

[0111] like Figure 7 As shown, it can be observed that the single scattering peak centered on the vector q = 0.038A-1 shows the typical scattering pattern of the bicontinuous structure. The curve is further fitted with the Teubner-Strey model to obtain a dTS of 16.3 nm and an amphiphilic factor fa = -0.42, which proves the existence of a molecular-scale bicontinuous network in 3-BRPO.

[0112] The Teubner-Strey model is derived from the literature: Bobrin, VA, Yao, Y., Shi, X. et al. Na no-tomacro-scale control of 3D printed materials via polymerization induced microphase separation. Nat Commun 13, 3577 (2022).

[0113] Experimental Example 6: Characterization of Heat Resistance of 3-BRPO Hybrid Resin

[0114] In this experimental example, 3-BRPO a, 3-BRPO b, 3-BRPO c and BPR were prepared according to the methods in Example 1 and Comparative Example 1.

[0115] 1. Experimental Methods

[0116] The heat resistance of the hybrid resin was characterized by thermogravimetry (TG).

[0117] 2. Experimental Results

[0118] like Figure 8As shown in the figure, the constructed organic-inorganic bicontinuous network can significantly improve the residual weight of the material at 1200°C in an air atmosphere, and to a certain extent slow down or inhibit the degradation of the resin at 800-1200°C. The constructed organic-inorganic bicontinuous network can significantly improve the residual weight of the material at 1200°C in an air atmosphere, and to a certain extent slow down or inhibit the degradation of the resin at 800-1200°C. Therefore, the hybrid resin exhibits good heat resistance.

[0119] Experimental Example 7: Static Ablation Performance of 3-BRPO Hybrid Resin

[0120] In this experimental example, 3-BRPO a and BPR were prepared according to the methods in Example 1 and Comparative Example 1.

[0121] 1. Experimental Methods

[0122] The static ablation performance of the hybrid resin was characterized by a tube furnace (1200°C for 30 min, heating rate of 5°C / min).

[0123] 2. Experimental Results

[0124] Figure 9 As can be seen from a and b, the hybrid resin generates a dense ceramic layer through high-temperature static ablation in an oxidizing atmosphere, and the structure remains intact, while the glassy carbon obtained from pure phenolic resin is completely oxidized. Figure 9 c The results show that the carbonized ceramic products of the hybrid resin after static ablation are mainly composed of amorphous carbon, calcium phosphate, calcium carbide and calcium oxide.

[0125] Experimental Example 8: Plasma Dynamic Ablation Performance of 3-BRPO Hybrid Resin

[0126] In this experimental example, 3-BRPO b and BPR were prepared according to the methods in Example 1 and Comparative Example 1.

[0127] 1. Experimental Methods

[0128] The dynamic ablation performance of the hybrid resin in an oxygen-rich atmosphere was characterized by a plasma ablation machine (0.5 MW / m2; nitrogen flow rate / oxygen flow rate = 1; ablation time 60 s).

[0129] 2. Experimental Results

[0130] Figure 10 As can be seen, the hybrid resin forms a dense ceramic layer upon ablation in an oxygen-rich atmosphere, while the glassy carbon obtained from pure phenolic resin is completely exposed to flames. The covalent-ionic bicontinuous hybrid resin exhibits excellent ablation resistance in an oxygen-rich environment, with a mass ablation rate 24% lower than that of the boron phenolic resin (BPR group). This demonstrates that the covalent-ionic bicontinuous network constructed by the present invention can effectively enhance the ablation resistance of resin materials.

[0131] Experimental Example 9: Mechanical properties of 3-BRPO hybrid resin

[0132] In this experimental example, 3-BRPOb and BPR were prepared according to the methods in Example 1 and Comparative Example 1.

[0133] I. Experimental method

[0134] The mechanical properties of the 3-BRPO hybrid resin were characterized by a nanoindenter.

[0135] II. Experimental results

[0136] Figure 11 It can be seen that the modulus of the 3-BRPO hybrid resin is increased by 52.4% compared with the pure BPR. This indicates that the successful construction of the organic-inorganic bicontinuous network in the hybrid resin greatly improves the modulus of the material, which can effectively improve the mechanical properties of the resin material.

[0137] In summary, the hybrid resin prepared by the present application has a covalent-ionic bicontinuous network with continuous structure from macroscopic to microscopic scale, and has excellent high-temperature oxidation resistance, ablation resistance and mechanical properties, and has a broad application prospect in the field of thermal protection materials.

Claims

1. A hybrid resin having ablation resistance, characterized in that: It is made by curing the following raw materials in parts by weight: 10-30 parts of salt containing metal cations, 4-10 parts of acid radical ion donor, 150-900 parts of end-capping agent, 5-30 parts of monomer compound, 2-120 parts of modified phenolic resin; The monomer compound is a compound having a carboxyl group at one end and a group capable of reacting with a phenolic resin at the other end; The modified phenolic resin is selected from any one of boron phenolic resin, epoxy modified phenolic resin, polyamide modified phenolic resin, silicone modified phenolic resin, dicyandiamide modified phenolic resin, polyvinyl acetal modified phenolic resin, and diphenyl ether formaldehyde resin; The blocking agent is selected from triethylamine; The preparation method of the hybrid resin having ablation resistance comprises the following steps: Step 1, preparing an inorganic ion oligomer using a salt containing a metal cation, a capping agent, and an acid ion donor; Step 2, reacting the monomer compound with the inorganic ion oligomer obtained in step 1 to obtain an organic functionalized inorganic ion oligomer; Step 3: reacting the modified phenolic resin with the organic functionalized inorganic ion oligomer obtained in step 2 to obtain a hybrid resin with ablation resistance.

2. The hybrid resin having ablation resistance according to claim 1, characterized in that: The group capable of reacting with the phenolic resin is selected from at least one of an epoxy group, a maleimide group, a cyanate group, an isocyanate group, an amino group, a carboxyl group, a hydroxyl group, an aldehyde group, a thiol group, and a boric acid group.

3. The hybrid resin having ablation resistance according to claim 1, characterized in that: It is made by curing the following raw materials in parts by weight: 12 parts of salt containing metal cations, 8 parts of acid radical ion donor, 166 parts of end-capping agent, 7 parts of monomer compound, 30 parts of modified phenolic resin.

4. The hybrid resin having ablation resistance according to any one of claims 1 to 3, characterized in that: The metal cation is selected from at least one of calcium ion, copper ion, manganese ion, zirconium ion, hafnium ion, magnesium ion, and iron ion; the anion of the salt containing metal cations is selected from at least one of chloride ion, carbonate ion, sulfate ion, nitrate ion, and phosphate ion.

5. The hybrid resin having ablation resistance according to any one of claims 1 to 3, characterized in that: The monomer compound is selected from at least one of phenylboronic acid compounds, hydroxybenzoic acid compounds, hydroxyphenylacetic acid compounds, hydroxyphenylpropionic acid compounds, thioglycolic acid compounds, and thiobenzoic acid compounds.

6. The hybrid resin having ablation resistance according to any one of claims 1 to 3, characterized in that: The acid ion donor is selected from at least one of phosphoric acid, CO2, sulfuric acid and nitric acid.

7. The hybrid resin having ablation resistance according to claim 1, characterized in that: In step 1, the preparation method of the inorganic ion oligomer is: Step 1.1, reacting a salt containing a metal cation with a complexing agent to obtain solution A; Step 1.2, reacting the acid ion donor with the complexing agent to obtain solution B; Step 1.3, after solution A reacts with solution B, a dispersion 1 of inorganic ion oligomers is obtained; Step 1.4, the inorganic ion oligomer dispersion 1 is centrifuged to obtain an inorganic ion oligomer gel, which is then washed and dispersed to obtain; And / or, in step 2, the preparation method of the organic functionalized inorganic ion oligomer is: Step 2.1, reacting the monomer compound with the inorganic ion oligomer to obtain a dispersion 1 of the organic functionalized inorganic ion oligomer; Step 2.2, centrifuging the organic functionalized inorganic ion oligomer dispersion 1 to obtain an organic functionalized inorganic ion oligomer gel, and then washing and dispersing the gel to obtain; And / or, in step 3, the preparation method of the hybrid resin is: reacting an organic functionalized inorganic ion oligomer with a modified phenolic resin, obtaining a hybrid resin gel by centrifugation, washing and drying to obtain a hybrid resin powder, and then curing to obtain the hybrid resin.

8. The method for preparing a hybrid resin having ablation resistance according to any one of claims 1 to 7, characterized in that: The steps include: Step 1, preparing an inorganic ion oligomer using a salt containing a metal cation, a capping agent, and an acid ion donor; Step 2, reacting the monomer compound with the inorganic ion oligomer obtained in step 1 to obtain an organic functionalized inorganic ion oligomer; Step 3: reacting the modified phenolic resin with the organic functionalized inorganic ion oligomer obtained in step 2 to obtain a hybrid resin with ablation resistance.

9. Use of the hybrid resin with ablation resistance according to any one of claims 1 to 7 in the preparation and / or as ablation resistant material.

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