Non-isocyanate type self-repairing elastomer as well as preparation method and application thereof

Abstract

The invention provides a non-isocyanate type self-repairing elastomer as well as a preparation method and application thereof, and belongs to the technical field of self-repairing materials. The non-isocyanate type self-repairing elastomer provided by the invention has a chemical structure as shown in a formula I or a formula II. Molecules in the non-isocyanate type self-repairing elastomer provided by the invention are connected through a plurality of hydrogen bonds to form a stable structure; h in two NH groups of each ureido molecule can form a hydrogen bond with O of an adjacent molecule, meanwhile, O of carbonyl on the ureido can accept H of other NH, a three-dimensional hydrogen bond cross-linked network is formed, and therefore a multi-stage and multi-hydrogen bond structure is formed, and the non-isocyanate type self-repairing elastomer is endowed with excellent mechanical properties through the multi-stage and multi-hydrogen bonds; due to the dynamic reversible characteristic of multiple and multistage hydrogen bonds, the elastomer can realize controllable dissociation and recombination of a hydrogen bond network in a room temperature environment, so that the self-repairing performance of the non-isocyanate type self-repairing elastomer is remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of self - healing materials, and particularly relates to a non - isocyanate self - healing elastomer and its preparation method and application. Background Art

[0002] At present, polyurea elastomers are mainly prepared by the reaction of isocyanates with diamines or polyamines. The raw materials involve highly toxic isocyanates, which do not meet the requirements of green chemical production. Secondly, the reaction time is too fast, resulting in cross - linking of polymer molecular chains, thus causing problems such as poor mechanical properties of the polymer and long repair cycles, severely restricting its application fields. Therefore, the research on the preparation of polyurea elastomers by non - isocyanate routes has very important scientific significance and application value.

[0003] Currently, non - isocyanate self - healing elastomers are mainly prepared by polycondensation reactions of urea, aminopoly(dimethylsiloxane) and 1,3 - bis(aminopropyl)tetramethyldisiloxane. However, the non - isocyanate self - healing elastomers prepared have poor tensile strength and impact resistance due to the lack of hard segments in their molecular structures, and at the same time, the self - healing performance is insufficient. Therefore, how to improve the self - healing ability and mechanical properties of non - isocyanate self - healing elastomers has become an urgent technical problem in this field. Summary of the Invention

[0004] The purpose of the present invention is to provide a non - isocyanate self - healing elastomer and its preparation method and application. The non - isocyanate self - healing elastomer provided by the present invention has excellent self - healing ability and mechanical properties.

[0005] In order to achieve the above - mentioned invention purpose, the present invention provides the following technical solutions: The present invention provides a non - isocyanate self - healing elastomer, which is characterized by having a chemical structure shown in Formula I or Formula II: Formula I; Formula II; In the said Formula I, R 1 is at least one of an alkyl group, an alicyclic group or an aromatic group, and R 2 is a polyether group, an alkylene group, an oxa - alkyl group or a polysiloxane group; In the said Formula II, R 3 is at least one of an alkyl group, an alicyclic group or an aromatic group, and R 4 is a polyether group or a polysiloxane group.

[0006] Preferably, in the said Formula I, x and y are independently 40 - 120, and in the said Formula II, m and n are independently 40 - 120.

[0007] The present invention also provides a method for preparing the non-isocyanate self-healing elastomer described in the above technical solution, comprising the following steps: (1) Mix urea and a diamine, and carry out a first polymerization reaction to obtain a first amino-terminated prepolymer; (2) Mix the first amino-terminated prepolymer obtained in step (1) with an amino-terminated compound, and carry out a second polymerization reaction to obtain a second amino-terminated prepolymer; (3) Carry out a first polycondensation reaction on the second amino-terminated prepolymer obtained in step (2) to obtain a non-isocyanate self-healing elastomer having a chemical structure of Formula I.

[0008] The present invention also provides a method for preparing the non-isocyanate self-healing elastomer described in the above technical solution, comprising the following steps: 1) Mix urea and a diamine, and carry out a first polymerization reaction to obtain a first amino-terminated prepolymer; 2) Mix the first amino-terminated prepolymer obtained in step 1) with a carboxyl-terminated polymer, and carry out a third polymerization reaction to obtain a prepolymer having an amino group at one end and a carboxyl group at the other end; 3) Carry out a second polycondensation reaction on the prepolymer having an amino group at one end and a carboxyl group at the other end obtained in step 2) to obtain a non-isocyanate self-healing elastomer having a chemical structure of Formula II.

[0009] Preferably, the molar ratio of urea to the diamine in step 1) is (1 to 2.01):1.

[0010] Preferably, the temperature of the first polymerization reaction in step 1) is 100 to 200 °C, and the time of the first polymerization reaction is 1 to 5 h.

[0011] Preferably, the carboxyl-terminated polymer in step 2) is at least one of dicarboxyl-terminated polyethylene glycol, dicarboxyl-terminated polypropylene glycol, dicarboxyl-terminated polybutylene glycol, and dicarboxyl-terminated polymethylsiloxane.

[0012] Preferably, the temperature of the third polymerization reaction in step 2) is 180 to 250 °C, and the time of the third polymerization reaction is 1 to 5 h.

[0013] Preferably, the temperature of the second polycondensation reaction in step 3) is 200 to 250 °C, the time of the second polycondensation reaction is 1 to 5 h, and the pressure of the second polycondensation reaction is 10 to 500 Pa.

[0014] The present invention also provides the application of the non-isocyanate self-healing elastomer described in the above technical solution or the non-isocyanate self-healing elastomer prepared by the preparation method described in the above technical solution in electronic instruments, surface protection, automobiles, biomedical materials, and intelligent materials.

[0015] The present invention provides a non-isocyanate self-healing elastomer having a chemical structure represented by Formula I or Formula II. In the non-isocyanate self-healing elastomer provided by the present invention, intermolecular connections are formed through multiple hydrogen bonds to form a stable structure; H in two NH groups of each ureido molecule can form hydrogen bonds with O of adjacent molecules, and at the same time, O of the carbonyl group on the ureido can also accept H of other NH to form a three-dimensional hydrogen bond network, thereby forming a multi-level and multiple hydrogen bond structure. The multi-level and multiple hydrogen bonds endow the non-isocyanate self-healing elastomer with excellent mechanical properties; the dynamic reversible characteristics of the multiple and multi-level hydrogen bonds enable the controllable dissociation and recombination of the hydrogen bond network of the elastomer at room temperature, thereby significantly improving the self-healing performance of the non-isocyanate self-healing elastomer. Experimental results show that the tensile strength of the non-isocyanate self-healing elastomer provided by the present invention is as high as 49 ± 2.5 MPa, the elongation at break is as high as 1597 ± 34%, and the toughness is as high as 196.9 ± 1.9 MJ·m -3 , the repair rate at room temperature for 0.5 h is as high as 29%, the repair rate at room temperature for 4 h is as high as 62%, the repair rate at room temperature for 12 h is as high as 89%, the repair rate at room temperature for 24 h is as high as 98%, and the light transmittance is as high as 98.6%. Description of the Drawings

[0016] Figure 1 1H NMR spectrum of the non-isocyanate self-healing elastomer prepared in Example 66. In the figure, a corresponds to the hydrogen on the ureido bond, b corresponds to the hydrogen on the soft segment polyether, and c corresponds to the hydrogen on isophorone diamine; Figure 2 Fourier transform infrared spectrum of the non-isocyanate self-healing elastomer prepared in Example 66; Figure 3 XRD spectrum of the non-isocyanate self-healing elastomer prepared in Example 66; Figure 4 Light transmittance curve of the non-isocyanate self-healing elastomer prepared in Example 66; Figure 5 Tensile curve of the non-isocyanate self-healing elastomer prepared in Example 66; Figure 6 Self-healing performance of the non-isocyanate self-healing elastomer prepared in Example 66. Detailed Embodiments

[0017] The present invention provides a non-isocyanate self-healing elastomer having a chemical structure represented by Formula I: Formula I; In the said Formula I, R 1 is at least one of an alkyl group, an alicyclic group, and an aromatic group, R 2It is a polyether group, alkylene group, oxaalkylene group, polysiloxane group, polyethylene glycol group, polypropylene glycol group or polybutylene glycol group.

[0018] In the present invention, the alkyl group is preferably a C2-C18 alkyl group. As an implementation manner, the alkyl group can be an ethyl group, propyl group, butyl group, pentyl group, hexyl group, octyl group, decyl group, undecyl group, dodecyl group, tridecyl group or pentadecyl group.

[0019] In the present invention, the alicyclic group is preferably , , , , , or ; the aromatic group is preferably , , , , , , , , , , , , , , , , , , , , , , , , , , , or .

[0020] In the present invention, the polyether group is preferably , , , , , polyethylene glycol group, polypropylene glycol group or polybutylene glycol group.

[0021] In the present invention, the polyethylene glycol group is preferably -PEG 1000 -, -PEG 2000 - or -PEG 3000 -; the polypropylene glycol group is preferably -PPG 1000 - or -PPG 5000 -; the polybutylene glycol group is preferably -PTMG 1000-, -PTMG 2000 - or -PTMG 5000 -.

[0022] In the present invention, the alkylene group is preferably ; the oxa-alkylene group is preferably , , or ; the polysiloxane group is preferably -PDMS 1000 -, -PDMS 3000 -, or -PDMS 5000 -.

[0023] In the present invention, x and y in formula I are independently preferably 40 to 120. As an embodiment, x and y can independently be 50, 60, 70, 80, 90, 100 or 110.

[0024] The present invention provides a non-isocyanate self-healing elastomer having a chemical structure shown in formula II: Formula II; In formula II, R 3 is at least one of an alkyl group, an alicyclic group or an aromatic group, and R 4 is a polyether group or a polysiloxane group.

[0025] In the present invention, the alkyl group is preferably the same as the alkyl group in formula I described above, and will not be elaborated here.

[0026] In the present invention, the alicyclic group is preferably the same as the alicyclic group in formula I described above, and will not be elaborated here; the aromatic group is preferably the same as the aromatic group in formula I described above, and will not be elaborated here.

[0027] In the present invention, the polyether group is preferably a polyethylene glycol group, a polypropylene glycol group or a polybutylene glycol group; the polyethylene glycol group is preferably -PEG 1000 -, -PEG 2000 -, or -PEG 3000 -; the polypropylene glycol group is preferably -PPG 3000 -; the polybutylene glycol group is preferably -PTMG 1000 -, or -PTMG 3000 -.

[0028] In the present invention, the polysiloxane group is preferably -PDMS 1000 -, -PDMS 3000 -, -PDMS 5000 -, or -PDMS 10000 -.

[0029] In the present invention, m and n in formula II are independently preferably 40 to 120. As an embodiment, m and n can independently be 50, 60, 70, 80, 90, 100, or 110.

[0030] In the non-isocyanate self-healing elastomer provided by the present invention, intermolecular connections are formed through multiple hydrogen bonds to form a stable structure; the H in the two NH groups of each ureido molecule can form hydrogen bonds with the O of adjacent molecules, and at the same time, the O of the carbonyl group on the ureido group can also accept the H of other NHs to form a three-dimensional hydrogen bond network, thereby forming a multi-level and multiple hydrogen bond structure. The multi-level and multiple hydrogen bonds endow the non-isocyanate self-healing elastomer with excellent mechanical properties; the dynamic reversible characteristics of the multiple and multi-level hydrogen bonds enable the controlled dissociation and recombination of the hydrogen bond network in the elastomer at room temperature, thereby significantly improving the self-healing performance of the non-isocyanate self-healing elastomer.

[0031] The non-isocyanate self-healing elastomer provided by the present invention forms a three-dimensional network structure by forming strong and weak interactions between ureido hydrogen bonds to obtain crosslinking points, enabling the non-isocyanate self-healing elastomer to have properties such as high strength, high toughness, and rapid repair. Therefore, it not only solves the problem of the use of isocyanates, but also solves the problems of insufficient mechanical properties, self-healing performance, and long repair time in the preparation of self-healing elastomers by the non-isocyanate method, meeting the application requirements of non-isocyanate self-healing elastomers in electronic instruments, surface protection, automobiles, biomedical materials, and intelligent materials.

[0032] The present invention has successfully solved the problem that highly toxic isocyanates are often required as raw materials in the preparation process of current self-healing polyurea elastomers, and at the same time solved the problems of poor mechanical properties and long repair time in the synthesis of self-healing elastomers using non-isocyanates as a route. The production process is green, environmentally friendly, and safe, and is conducive to alleviating the greenhouse effect; the non-isocyanate self-healing elastomer of the present invention has characteristics such as high tensile strength, strong recyclability, and fast room-temperature self-healing ability, and is expected to replace most of the polyurea elastomer polymers synthesized by the isocyanate route, with a wide range of application fields.

[0033] The present invention also provides a preparation method of the non-isocyanate self-healing elastomer described in the above technical solution, including the following steps: (1) Mix urea and diamine and carry out a first polymerization reaction to obtain a first amino-terminated prepolymer; (2) Mix the first amino-terminated prepolymer obtained in step (1) with an amino-terminated compound and carry out a second polymerization reaction to obtain a second amino-terminated prepolymer; (3) Carry out a first polycondensation reaction on the second amino-terminated prepolymer obtained in step (2) to obtain a non-isocyanate self-healing elastomer with a chemical structure of formula I.

[0034] The present invention does not impose any special restrictions on the sources of the various raw materials, and commercially available products well-known to those skilled in the art can be used.

[0035] In the present invention, the "first" and "second" have no special meaning and are only used to distinguish the respective reactions.

[0036] The present invention mixes urea with a diamine and conducts a first polymerization reaction to obtain a prepolymer terminated with a first amino group.

[0037] In the present invention, the diamine is preferably at least one of an aromatic diamine, an alicyclic diamine, and an aliphatic diamine, and more preferably an aromatic diamine and an aliphatic diamine.

[0038] In the present invention, when the diamine is an aromatic diamine and an aliphatic diamine, the molar ratio of the aromatic diamine to the aliphatic diamine is preferably 1:1 or 3:2.

[0039] In the present invention, the aromatic diamine is preferably at least one of m-phenylenediamine, p-phenylenediamine, 2-nitro-1,4-phenylenediamine, 2,5-dibromo-p-phenylenediamine, 2-methyl-p-phenylenediamine, 2,5-dimethoxy-p-phenylenediamine, 2,5-bis(methylsulfonyl)-1,4-phenylenediamine, tetramethyl-p-phenylenediamine, 2,3,5,6-tetrafluoro-p-xylylenediamine, 2-fluoro-5-methyl-1,4-phenylenediamine, 2-hydroxyethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, 2,6-diaminopyridine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodicyclohexylbenzene, 4,4'-diaminotriphenylmethane, 4,4'-diaminobenzophenone, 4,4'-diamino-3,3'-dimethyl-diphenylcyclohexane, 2,2'-bis(trifluoromethyl)diaminobiphenyl, 2,2-bis(4-aminophenyl)hexafluoropropane, 1,3-bis(3-aminophenoxy)benzene, 2,2'-bis[4-(4-aminophenoxyphenyl)]propane, 2,5-diaminobenzenesulfonic acid, 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene, bis(4-amino-2,3-dichlorophenyl)methane, 2-(4-aminophenyl)-5-aminobenzimidazole, 2,5-dichloro-1,4-phenylenediamine, 2,6-dichloro-1,4-phenylenediamine, 4,4-diaminodiphenyl sulfide, and 4,4'-methylenebis(2-toluidine).

[0040] In the present invention, the alicyclic diamine is preferably at least one of isophorone diamine, 1,3-cyclohexanediamine, 2-methyl-1,3-cyclohexanediamine, 5,5-dimethyl-1,3-cyclohexanediamine, 1,3-cyclopentanediamine, 1,2-cyclohexanediamine, 4,4'-diaminodicyclohexylmethane, and 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane.

[0041] In the present invention, the aliphatic diamine is preferably at least one of ethylenediamine, butanediamine, pentanediamine, hexanediamine, octanediamine, decanediamine, undecanediamine, dodecanediamine, tridecanediamine, and pentadecanediamine.

[0042] In the present invention, the molar ratio of the urea to the diamine is preferably (1 to 2.01):1. As an embodiment, the molar ratio of the urea to the diamine can be 1:1, 1.5:1, or 2:1. Limiting the molar ratio of the urea to the diamine within the above range in the present invention is beneficial to increasing the degree of the first polymerization reaction.

[0043] The present invention has no special limitation on the operation of mixing the urea and the diamine, and a technical solution for preparing a mixed material well-known to those skilled in the art can be adopted.

[0044] In the present invention, the temperature of the first polymerization reaction is preferably 100 to 200 °C; the time of the first polymerization reaction is preferably 1 to 5 h. As an embodiment, the temperature of the first polymerization reaction can be 110 °C, 120 °C, 130 °C, 140 °C, 150 °C, 160 °C, 170 °C, 180 °C, or 190 °C; the time of the first polymerization reaction can be 2 h, 3 h, or 4 h. Limiting the temperature and time of the first polymerization reaction within the above range in the present invention is beneficial to increasing the degree of the first polymerization reaction and improving the yield.

[0045] In the present invention, the first polymerization reaction is preferably carried out under normal pressure.

[0046] In the present invention, the first polymerization reaction is preferably carried out in a nitrogen atmosphere. Carrying out the first polymerization reaction in a nitrogen atmosphere in the present invention can avoid contact with air and affect the quality of the product.

[0047] In the present invention, the structural formula of the first amino-terminated prepolymer is preferably as shown in Formula III: Formula III.

[0048] In the present invention, the R 1 is preferably the same as the R in the aforementioned Formula I 1 and will not be elaborated herein.

[0049] After obtaining the first amino-terminated prepolymer, the present invention mixes the first amino-terminated prepolymer with an amino-terminated compound and carries out a second polymerization reaction to obtain a second amino-terminated prepolymer.

[0050] In the present invention, the amino-terminated compound is preferably at least one of 1,5-diamino-2-methylpentane, 1,8-diamino-3,6-dioxaoctane, 1,10-diamino-4,7-dioxadecane, 1,12-diamino-4,9-dioxadodecane, 1,13-diamino-4,7,10-trioxatridecane, polyetheramine, dimethylamino-terminated dimethylpolysiloxane, dimethylamino-terminated polyethylene glycol, diamino-terminated polypropylene glycol and diamino-terminated polybutylene glycol.

[0051] As an embodiment, the amino-terminated compound can be polyetheramine 2000, polyetheramine 230, polyetheramine 400, polyetheramine 800, polyetheramine 1000, NH 2 -PEG 1000 -NH 2 NH 2 -PEG 2000 -NH 2 NH 2 -PEG 3000 -NH 2 NH 2 -PDMS 3000 -NH 2 NH 2 -PDMS 5000 -NH 2 NH 2 -PTMG 1000 -NH 2 NH 2 -PTMG 2000 -NH 2 NH 2 -PTMG 5000 -NH 2 NH 2 -PPG 1000 -NH 2 or NH 2 -PPG 5000 -NH 2 .

[0052] In the present invention, the molar ratio of the diamine to the amino-terminated compound is preferably 1:(1-5.01). As an embodiment, the molar ratio of the diamine to the amino-terminated compound may be 1:2, 1:3, 1:4 or 1:5. In the present invention, limiting the molar ratio of the diamine to the amino-terminated compound within the above range can further improve the degree of the third polymerization reaction.

[0053] The present invention has no special limitation on the operation of mixing the first amino-terminated prepolymer and the amino-terminated compound, and the technical scheme for preparing the mixed material well known to those skilled in the art can be adopted.

[0054] In the present invention, the temperature of the second polymerization reaction is preferably 180 to 250 °C; the time of the second polymerization reaction is preferably 2 to 6 h. As an embodiment, the temperature of the second polymerization reaction can be 190 °C, 200 °C, 210 °C, 220 °C, 230 °C or 240 °C; the time of the second polymerization reaction can be 3 h, 4 h or 5 h. Limiting the temperature and time of the second polymerization reaction within the above ranges in the present invention can improve the degree of the second polymerization reaction.

[0055] In the present invention, the second polymerization reaction is preferably carried out in a nitrogen atmosphere. Carrying out the second polymerization reaction in a nitrogen atmosphere in the present invention can avoid contact with air and affect the quality of the product.

[0056] In the present invention, the structural formula of the second amino-terminated prepolymer is preferably as shown in Formula IV: Formula IV.

[0057] In the present invention, the R 1 and R 2 are preferably the same as R 1 and R 2 in the aforementioned Formula I, and will not be elaborated here.

[0058] After obtaining the second amino-terminated prepolymer, the present invention carries out a first polycondensation reaction on the second amino-terminated prepolymer to obtain a non-isocyanate self-healing elastomer having the chemical structure of Formula I.

[0059] In the present invention, the temperature of the first polycondensation reaction is preferably 200 to 250 °C; the time of the first polycondensation reaction is preferably 1 to 5 h; the pressure of the first polycondensation reaction is preferably 10 to 500 Pa. As an embodiment, the temperature of the first polycondensation reaction can be 210 °C, 220 °C, 230 °C or 240 °C; the time of the first polycondensation reaction can be 2 h, 3 h or 4 h; the pressure of the first polycondensation reaction can be 50 to 250 Pa, and can also be 100 to 150 Pa.

[0060] The present invention also provides a preparation method of the non-isocyanate self-healing elastomer described in the above technical solution, including the following steps: 1) Mix urea and diamine, and carry out a first polymerization reaction to obtain a first amino-terminated prepolymer; 2) Carry out a third polymerization reaction on the first amino-terminated prepolymer obtained in the step 1) and a carboxyl-terminated polymer to obtain a prepolymer with one amino group at one end and one carboxyl group at the other end; 3) Carry out a second polycondensation reaction on the prepolymer with one amino group at one end and one carboxyl group at the other end obtained in the step 2) to obtain a non-isocyanate self-healing elastomer with a chemical structure of formula II.

[0061] The present invention has no special limitation on the sources of each raw material, and commercially available products well-known to those skilled in the art can be used.

[0062] In the present invention, the first and the third have no special meanings, and are only used to distinguish each reaction.

[0063] The present invention mixes urea and diamine and carries out a first polymerization reaction to obtain a prepolymer capped with amino groups at one end.

[0064] In the present invention, the method for preparing the prepolymer capped with amino groups at one end is preferably the same as the foregoing operation, and will not be elaborated herein.

[0065] After obtaining the prepolymer capped with amino groups at one end, the present invention carries out a third polymerization reaction on the prepolymer capped with amino groups at one end and the polymer capped with carboxyl groups to obtain a prepolymer with one amino group at one end and one carboxyl group at the other end.

[0066] In the present invention, the polymer capped with carboxyl groups is preferably at least one of dicarboxyl-terminated polyethylene glycol, dicarboxyl-terminated polypropylene glycol, dicarboxyl-terminated polybutylene glycol, and dicarboxyl-terminated polymethylsiloxane.

[0067] As an implementation manner, the polymer capped with carboxyl groups can be COOH-PEG 1000 -COOH, COOH-PEG 2000 -COOH, COOH-PEG 3000 -COOH, COOH-PTMG 1000 -COOH, COOH-PTMG 3000 -COOH, COOH-PDMS 1000 -COOH, COOH-PDMS 3000 -COOH, COOH-PDMS 5000 -COOH, COOH-PDMS 10000 -COOH or COOH-PPG 3000 -COOH.

[0068] In the present invention, the molar ratio of the diamine to the polymer capped with carboxyl groups is preferably 1:(1 - 5.01). As an implementation manner, the molar ratio of the diamine to the polymer capped with carboxyl groups can be 1:1.5, 1:2, 1:3, 1:4, or 1:5. Limiting the molar ratio of the diamine to the polymer capped with carboxyl groups within the above range in the present invention can further improve the degree of the third polymerization reaction.

[0069] The present invention has no special limitation on the operation of mixing the first amino - terminated prepolymer and the carboxyl - terminated polymer, and the technical solutions for preparing the mixed material well - known to those skilled in the art can be adopted.

[0070] In the present invention, the temperature of the third polymerization reaction is preferably 180 - 250 °C; the time of the third polymerization reaction is preferably 2 - 6 h. As an implementation manner, the temperature of the third polymerization reaction can be 190 °C, 200 °C, 210 °C, 220 °C, 230 °C or 240 °C; the time of the third polymerization reaction can be 3 h, 4 h or 5 h. Limiting the temperature and time of the third polymerization reaction within the above ranges in the present invention can improve the degree of the third polymerization reaction.

[0071] In the present invention, the third polymerization reaction is preferably carried out in a nitrogen atmosphere. Conducting the third polymerization reaction in a nitrogen atmosphere in the present invention can avoid contact with air and affect the quality of the product.

[0072] In the present invention, the structural formula of the prepolymer with one amino group at one end and one carboxyl group at the other end is preferably as shown in Formula V: Formula V.

[0073] In the present invention, the R 3 and R 4 are preferably the same as R 3 and R 4 in the aforementioned Formula II, which will not be elaborated here.

[0074] After obtaining the prepolymer with one amino group at one end and one carboxyl group at the other end, the present invention conducts the second polycondensation reaction on the prepolymer with one amino group at one end and one carboxyl group at the other end to obtain a non - isocyanate - type self - healing elastomer with the chemical structure of Formula II.

[0075] In the present invention, the temperature of the second polycondensation reaction is preferably 200 - 250 °C; the time of the second polycondensation reaction is preferably 1 - 5 h; the pressure of the second polycondensation reaction is preferably 10 - 500 Pa. As an implementation manner, the temperature of the second polycondensation reaction can be 210 °C, 220 °C, 230 °C or 240 °C; the time of the second polycondensation reaction can be 2 h, 3 h or 4 h; the pressure of the second polycondensation reaction can be 50 - 250 Pa, and can also be 100 - 150 Pa.

[0076] The present invention uses urea as a reactive carbonyl source to prepare an amino-terminated prepolymer with strong hydrogen bond network interactions with diamine under mild conditions, and then rapidly reacts with an amino-terminated compound or a carboxyl-terminated polymer to obtain an elastomeric material with a three-dimensional network structure, realizing the preparation of a non-isocyanate self-healing elastomer with high strength, high toughness, high transparency and rapid repair to meet the application requirements of non-isocyanate self-healing elastomers in electronic instruments, surface protection, automobiles, biomedical materials and intelligent materials.

[0077] The present invention adopts a non-isocyanate route, uses urea to react with diamine to obtain a urea-terminated hard segment, and finally reacts with an amino-terminated compound or a carboxyl-terminated polymer to obtain a non-isocyanate self-healing elastomer.

[0078] The present invention also provides the application of the non-isocyanate self-healing elastomer described in the above technical solution or the non-isocyanate self-healing elastomer prepared by the preparation method described in the above technical solution in electronic instruments, surface protection, automobiles, biomedical materials and intelligent materials.

[0079] The present invention has no special limitation on the operation of the application of the non-isocyanate self-healing elastomer in electronic instruments, surface protection, automobiles, biomedical materials and intelligent materials, and the application operations well-known to those skilled in the art can be adopted.

[0080] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the embodiments in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the protection scope of the present invention.

[0081] Example 1 The non-isocyanate self-healing elastomer has the chemical structure described in Formula I: In the Formula I, R 1 is , R 2 is -PEG 2000 -; x is 58 and y is 112; The preparation method of the non-isocyanate self-healing elastomer is as follows: (1) Under nitrogen protection, urea and m-phenylenediamine are put into a reaction kettle, and the molar ratio of urea to m-phenylenediamine is 2.01:1. The first polymerization reaction is carried out at normal pressure (101.325 KPa) and 180 °C for 2 h to obtain a first amino-terminated prepolymer; (2) NH 2-PEG 2000 -NH 2 , perform the second polymerization reaction at 240 °C for 2 h to obtain a second amino-terminated prepolymer; wherein, the molar ratio of m-phenylenediamine to NH 2 -PEG 2000 -NH 2 is 1:1; (3) Reduce the pressure to 50 Pa, and perform the first polycondensation reaction on the second amino-terminated prepolymer obtained in step (2) at 250 °C for 4 h to obtain a non-isocyanate self-healing elastomer.

[0082] Example 2 On the basis of Example 1, modify R 1 to , modify m-phenylenediamine to p-phenylenediamine, and keep other conditions unchanged to obtain a non-isocyanate self-healing elastomer.

[0083] Example 3 On the basis of Example 1, modify R 1 to , modify m-phenylenediamine to 2-nitro-1,4-phenylenediamine, and keep other conditions unchanged to obtain a non-isocyanate self-healing elastomer.

[0084] Example 4 On the basis of Example 1, modify R 1 to , modify m-phenylenediamine to 2,5-dibromo-p-phenylenediamine, and keep other conditions unchanged to obtain a non-isocyanate self-healing elastomer.

[0085] Example 5 On the basis of Example 1, modify R 1 to , modify m-phenylenediamine to 2-methyl-p-phenylenediamine, and keep other conditions unchanged to obtain a non-isocyanate self-healing elastomer.

[0086] Example 6 On the basis of Example 1, modify R 1 to , modify m-phenylenediamine to 2,5-dimethoxy-p-phenylenediamine, and keep other conditions unchanged to obtain a non-isocyanate self-healing elastomer.

[0087] Example 7 On the basis of Example 1, modify R 1 to , modify m-phenylenediamine to 2,5-bis(methylsulfonyl)-1,4-phenylenediamine, and keep other conditions unchanged to obtain a non-isocyanate self-healing elastomer.

[0088] Example 8 On the basis of Example 1, R 1 is modified to , and m-phenylenediamine is modified to 2,3,5,6-tetrafluoroterephthalamine, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer.

[0089] Example 9 On the basis of Example 1, R 1 is modified to , and m-phenylenediamine is modified to 2-fluoro-5-methyl-1,4-phenylenediamine, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer.

[0090] Example 10 On the basis of Example 1, R 1 is modified to , and m-phenylenediamine is modified to 2-hydroxyethyl-p-phenylenediamine, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer.

[0091] Example 11 On the basis of Example 1, the temperature of the first polymerization reaction is modified to 100 °C, and the time of the first polymerization reaction is modified to 5 h, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer, where x is 41 and y is 82 in Formula I.

[0092] Example 12 On the basis of Example 1, the temperature of the first polymerization reaction is modified to 140 °C, and the time of the first polymerization reaction is modified to 3 h, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer, where x is 45 and y is 85 in Formula I.

[0093] Example 13 On the basis of Example 1, the temperature of the first polymerization reaction is modified to 200 °C, and the time of the first polymerization reaction is modified to 2 h, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer, where x is 85 and y is 110 in Formula I.

[0094] Example 14 On the basis of Example 1, the temperature of the second polymerization reaction is modified to 200 °C, and the time of the second polymerization reaction is modified to 2 h, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer, where x is 75 and y is 85 in Formula I.

[0095] Example 15 On the basis of Example 1, the temperature of the first polycondensation reaction is modified to 200 °C, and the pressure of the first polycondensation reaction is 500 Pa, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer, where x is 85 and y is 58 in Formula I.

[0096] The non-isocyanate self-healing elastomers prepared in Examples 1 to 15 were subjected to performance tests, and the results are shown in Table 1. Among them, for the light transmittance test, the ultraviolet-visible transmission spectrum was measured by a Shimadzu UV-2700 in Japan, and the test wavelength was in the range of 400 - 800 nm. For the mechanical property test, the stress-strain data of the samples were measured by a universal material testing machine (INSTRON5900) at room temperature, and the tensile rate was 50 mm / min. The stress-strain curve of the specimen was tested by an Instron5944 testing machine with a tensile rate of 50 mm / min at room temperature. The calculation formula for the repair rate is as follows: ; where σ (healing) and σ (initial) are the tensile strengths of the specimen in the healed and initial states, respectively.

[0097] Table 1 Performance data of the non-isocyanate self-healing elastomers prepared in Examples 1 to 15

[0098] Example 16 On the basis of Example 1, R 1 was modified to , and m-phenylenediamine was modified to 1,3-cyclohexanediamine, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer.

[0099] Example 17 On the basis of Example 1, R 1 was modified to , and m-phenylenediamine was modified to 2-methyl-1,3-cyclohexanediamine, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer.

[0100] Example 18 On the basis of Example 1, R 1 was modified to , and m-phenylenediamine was modified to 5,5-dimethyl-1,3-cyclohexanediamine, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer.

[0101] Example 19 On the basis of Example 1, R 1 was modified to , and m-phenylenediamine was modified to 1,3-cyclopentanediamine, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer.

[0102] Example 20 On the basis of Example 1, R 1 was modified to , and m-phenylenediamine was modified to 1,2-cyclohexanediamine, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer.

[0103] Example 21 On the basis of Example 1, R 1 was modified to , and m-phenylenediamine was modified to 4,4'-diaminodicyclohexylmethane, with other conditions remaining unchanged, to obtain a non-isocyanate self-healing elastomer.

[0104] Example 22 The non-isocyanate self-healing elastomer has the chemical structure shown in Formula I: In the said Formula I, R 1 is , R 2 is -PEG 2000 -; The said x is 76 and y is 112; The preparation method of the said non-isocyanate self-healing elastomer is as follows: (1) Under nitrogen protection, urea and m-phenylenediamine were put into a reaction kettle, where the molar ratio of urea to m-phenylenediamine was 2.01:1, and the first polymerization reaction was carried out at normal pressure (101.325 KPa) and 180 °C for 2 h to obtain a first amino-terminated prepolymer; (2) NH 2 -PEG 2000 -NH 2 was added to the first amino-terminated prepolymer obtained in the said step (1), and the second polymerization reaction was carried out at 230 °C for 5 h to obtain a second amino-terminated prepolymer; among them, the molar ratio of m-phenylenediamine to NH 2 -PEG 2000 -NH 2 was 1:5; (3) The pressure was reduced to 50 Pa, and the second amino-terminated prepolymer obtained in the said step (2) was subjected to the first polycondensation reaction at 250 °C for 4 h to obtain a non-isocyanate self-healing elastomer.

[0105] Example 23 The non-isocyanate self-healing elastomer has the chemical structure shown in Formula I: In the said Formula I, R 1 is , R 2 is -PEG 2000 -; The said x is 88 and y is 102; The preparation method of the said non-isocyanate self-healing elastomer is as follows: (1) Under nitrogen protection, urea and m-phenylenediamine are put into a reaction kettle, where the molar ratio of urea to m-phenylenediamine is 2.01:1. The first polymerization reaction is carried out at normal pressure (101.325 KPa) and 180 °C for 2 h to obtain a prepolymer capped with a first amino group; (2) NH 2 -PEG 2000 -NH 2 is added to the prepolymer capped with a first amino group obtained in the step (1), and the second polymerization reaction is carried out at 200 °C for 6 h to obtain a prepolymer capped with a second amino group; among them, the molar ratio of m-phenylenediamine to NH 2 -PEG 2000 -NH 2 is 1:3; (3) The pressure is reduced to 50 Pa, and the prepolymer capped with a second amino group obtained in the step (2) is subjected to a first polycondensation reaction at 230 °C for 4 h to obtain a non-isocyanate-based self-healing elastomer.

[0106] Example 24 The non-isocyanate-based self-healing elastomer has the chemical structure shown in Formula I: In the said Formula I, R 1 is and R 2 is -PEG 2000 -; The said x is 75 and y is 115; The preparation method of the non-isocyanate-based self-healing elastomer is as follows: (1) Under nitrogen protection, urea and m-phenylenediamine are put into a reaction kettle, where the molar ratio of urea to m-phenylenediamine is 2.01:1. The first polymerization reaction is carried out at normal pressure (101.325 KPa) and 180 °C for 2 h to obtain a prepolymer capped with a first amino group; (2) NH 2 -PEG 2000 -NH 2 is added to the prepolymer capped with a first amino group obtained in the step (1), and the second polymerization reaction is carried out at 250 °C for 4 h to obtain a prepolymer capped with a second amino group; among them, the molar ratio of m-phenylenediamine to NH 2 -PEG 2000 -NH 2 is 1:2; (3) The pressure is reduced to 100 Pa, and the prepolymer capped with a second amino group obtained in the step (2) is subjected to a first polycondensation reaction at 200 °C for 5 h to obtain a non-isocyanate-based self-healing elastomer.

[0107] Example 25 The non-isocyanate-based self-healing elastomer has the chemical structure shown in Formula I: In the formula I, R 1 is , R 2 is -PEG 2000 -; x is 88 and y is 113; The preparation method of the non-isocyanate self-healing elastomer is as follows: (1) Under nitrogen protection, urea and m-phenylenediamine are put into a reaction kettle, and the molar ratio of urea to m-phenylenediamine is 2.01:1. The first polymerization reaction is carried out at normal pressure (101.325 KPa) and 180 °C for 2 h to obtain a first amino-terminated prepolymer; (2) NH 2 -PEG 2000 -NH 2 is added to the first amino-terminated prepolymer obtained in the step (1), and the second polymerization reaction is carried out at 200 °C for 6 h to obtain a second amino-terminated prepolymer; among them, the molar ratio of m-phenylenediamine to NH 2 -PEG 2000 -NH 2 is 1:4; (3) The pressure is reduced to 100 Pa, and the second amino-terminated prepolymer obtained in the step (2) is subjected to the first polycondensation reaction at 250 °C for 2 h to obtain a non-isocyanate self-healing elastomer.

[0108] The performance of the non-isocyanate self-healing elastomers prepared in Examples 16-25 was tested according to the test method in Table 1, and the results are shown in Table 2.

[0109] Table 2 Performance data of the non-isocyanate self-healing elastomers prepared in Examples 16-25

[0110] Example 26 On the basis of Example 1, R 2 is modified to , NH 2 -PEG 2000 -NH 2 is modified to 1,5-diamino-2-methylpentane, and other conditions remain unchanged to obtain a non-isocyanate self-healing elastomer.

[0111] Example 27 On the basis of Example 2, R 2 is modified to , NH 2 -PEG 2000 -NH 2Modify it to 1,8-diamino-3,6-dioxaoctane, with other conditions remaining unchanged, to obtain a non-isocyanate type self-healing elastomer.

[0112] Example 28 Based on Example 3, modify R 2 to , NH 2 -PEG 2000 -NH 2 Modify it to 1,10-diamino-4,7-dioxadecane (i.e., ethylene glycol bis(3-aminopropyl) ether), with other conditions remaining unchanged, to obtain a non-isocyanate type self-healing elastomer.

[0113] Example 29 Based on Example 4, modify R 2 to , NH 2 -PEG 2000 -NH 2 Modify it to 1,12-diamino-4,9-dioxadodecane, with other conditions remaining unchanged, to obtain a non-isocyanate type self-healing elastomer.

[0114] Example 30 Based on Example 5, modify R 2 to , NH 2 -PEG 2000 -NH 2 Modify it to 1,13-diamino-4,7,10-trioxatridecane, with other conditions remaining unchanged, to obtain a non-isocyanate type self-healing elastomer.

[0115] Example 31 Based on Example 6, modify R 2 to , NH 2 -PEG 2000 -NH 2 Modify it to polyetheramine 2000, with other conditions remaining unchanged, to obtain a non-isocyanate type self-healing elastomer.

[0116] Example 32 Based on Example 7, modify R 2 to , NH 2 -PEG 2000 -NH 2 Modify it to polyetheramine 400, with other conditions remaining unchanged, to obtain a non-isocyanate type self-healing elastomer.

[0117] Example 33 Based on Example 8, modify R 2 to , NH 2 -PEG 2000 -NH 2 It was modified to polyetheramine 800, and other conditions remained unchanged to obtain a non-isocyanate self-healing elastomer.

[0118] Example 34 Based on Example 9, R 2 was modified to , NH 2 -PEG 2000 -NH 2 It was modified to polyetheramine 1000, and other conditions remained unchanged to obtain a non-isocyanate self-healing elastomer.

[0119] Example 35 Based on Example 10, R 2 was modified to , NH 2 -PEG 2000 -NH 2 It was modified to polyetheramine 230, and other conditions remained unchanged to obtain a non-isocyanate self-healing elastomer.

[0120] The non-isocyanate self-healing elastomers prepared in Examples 26 to 35 were subjected to performance tests according to the test method in Table 1, and the results are shown in Table 3.

[0121] Table 3 Performance data of the non-isocyanate self-healing elastomers prepared in Examples 26 to 35

[0122] Example 36 Based on Example 1, R 2 was modified to -PEG 1000 -, NH 2 -PEG 2000 -NH 2 was modified to NH 2 -PEG 1000 -NH 2 , and other conditions remained unchanged to obtain a non-isocyanate self-healing elastomer.

[0123] Example 37 Based on Example 2, R 2 was modified to -PEG 3000 -,, NH 2 -PEG 2000 -NH 2 was modified to NH 2 -PEG 3000 -NH 2, with other conditions remaining unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0124] Example 38 On the basis of Example 3, R 2 is modified to -PDMS 1000 -, NH 2 -PEG 2000 -NH 2 is modified to NH 2 -PDMS 1000 -NH 2 , with other conditions remaining unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0125] Example 39 On the basis of Example 4, R 2 is modified to -PDMS 5000 -, NH 2 -PEG 2000 -NH 2 is modified to NH 2 -PDMS 5000 -NH 2 , with other conditions remaining unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0126] Example 40 On the basis of Example 5, R 2 is modified to -PDMS 3000 -, NH 2 -PEG 2000 -NH 2 is modified to NH 2 -PDMS 3000 -NH 2 , with other conditions remaining unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0127] Example 41 On the basis of Example 6, R 2 is modified to -PTMG 1000 -, NH 2 -PEG 2000 -NH 2 is modified to NH 2 -PTMG 1000 -NH 2 , with other conditions remaining unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0128] Example 42 On the basis of Example 7, R 2 is modified to -PTMG 2000 -, NH 2 -PEG 2000-NH 2 Modify to NH 2 -PTMG 2000 -NH 2 , with other conditions unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0129] Example 43 Based on Example 8, change R 2 Modify to -PTMG 5000 -, NH 2 -PEG 2000 -NH 2 Modify to NH 2 -PTMG 5000 -NH 2 , with other conditions unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0130] Example 44 Based on Example 9, change R 2 Modify to -PPG 5000 -, NH 2 -PEG 2000 -NH 2 Modify to NH 2 -PPG 5000 -NH 2 , with other conditions unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0131] Example 45 Based on Example 10, change R 2 Modify to -PPG 1000 -, NH 2 -PEG 2000 -NH 2 Modify to NH 2 -PPG 1000 -NH 2 , with other conditions unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0132] Perform performance tests on the non-isocyanate type self-healing elastomers prepared in Examples 36 to 45 according to the test method in Table 1, and the results are shown in Table 4.

[0133] Table 4 Performance data of the non-isocyanate type self-healing elastomers prepared in Examples 36 to 45

[0134] Example 46 Based on Example 1, change R 1 Modify to and , m-Phenylenediamine was modified to ethylenediamine and p-phenylenediamine (molar ratio 1:1), and other conditions remained unchanged, obtaining a non-isocyanate self-healing elastomer.

[0135] Example 47 On the basis of Example 1, R 1 was modified to , m-Phenylenediamine was modified to propylenediamine, and other conditions remained unchanged, obtaining a non-isocyanate self-healing elastomer.

[0136] Example 48 On the basis of Example 1, R 1 was modified to and , m-Phenylenediamine was modified to butylenediamine and m-phenylenediamine (molar ratio 1:1), and other conditions remained unchanged, obtaining a non-isocyanate self-healing elastomer.

[0137] Example 49 On the basis of Example 1, R 1 was modified to and , m-Phenylenediamine was modified to pentylenediamine and 2-fluoro-5-methyl-1,4-phenylenediamine (molar ratio 1:1), and other conditions remained unchanged, obtaining a non-isocyanate self-healing elastomer.

[0138] Example 50 On the basis of Example 1, R 1 was modified to and , m-Phenylenediamine was modified to hexamethylenediamine and 4,4'-diaminodiphenylmethane (molar ratio 1:1), and other conditions remained unchanged, obtaining a non-isocyanate self-healing elastomer.

[0139] Example 51 On the basis of Example 1, R 1 was modified to and , m-Phenylenediamine was modified to dodecamethylenediamine and 4,4'-diaminotriphenylmethane (molar ratio 1:1), and other conditions remained unchanged, obtaining a non-isocyanate self-healing elastomer.

[0140] Example 52 On the basis of Example 22, R 1 was modified to and , m-Phenylenediamine was modified to hexamethylenediamine and 4,4'-diamino-3,3'-dimethyl-diphenylcyclohexane (molar ratio 1:1), and other conditions remained unchanged, obtaining a non-isocyanate self-healing elastomer.

[0141] Example 53 On the basis of Example 23, R 1 is modified to and , and m-phenylenediamine is modified to hexamethylenediamine and 2,2-bis(4-aminophenyl)hexafluoropropane (the molar ratio is 1:1). Under other unchanged conditions, a non-isocyanate self-healing elastomer is obtained.

[0142] Example 54 On the basis of Example 24, R 1 is modified to and , and m-phenylenediamine is modified to hexamethylenediamine and p-phenylenediamine (the molar ratio is 2:3). Under other unchanged conditions, a non-isocyanate self-healing elastomer is obtained.

[0143] Example 55 On the basis of Example 25, R 1 is modified to and , and m-phenylenediamine is modified to hexamethylenediamine and p-phenylenediamine (the molar ratio is 2:3). Under other unchanged conditions, a non-isocyanate self-healing elastomer is obtained.

[0144] The non-isocyanate self-healing elastomers prepared in Examples 46 to 55 were subjected to performance tests according to the test method in Table 1, and the results are shown in Table 5.

[0145] Table 5 Performance data of the non-isocyanate self-healing elastomers prepared in Examples 46 to 55

[0146] Example 56 The non-isocyanate self-healing elastomer has the chemical structure described in Formula II: In the said Formula II, R 3 is , R 4 is -PEG 1000 -; The said m is 75 and n is 115; The preparation method of the said non-isocyanate self-healing elastomer is: (1) Under nitrogen protection, urea and m-phenylenediamine are put into a reaction kettle, wherein the molar ratio of urea to m-phenylenediamine is 2.01:1. A first polymerization reaction is carried out at normal pressure (101.325 KPa) and 180 °C for 2 h to obtain a first amino-terminated prepolymer; (2) COOH-PEG is added to the first amino-terminated prepolymer obtained in the said step (1) 1000-COOH, perform the second polymerization reaction at 240 °C for 2 h to obtain a second amino-terminated prepolymer; wherein, the molar ratio of m-phenylenediamine to COOH-PEG 1000 -COOH is 1:4; (3) Reduce the pressure to 100 Pa, and perform the first polycondensation reaction on the second amino-terminated prepolymer obtained in step (2) at 250 °C for 2 h to obtain a non-isocyanate self-healing elastomer.

[0147] Example 57 The non-isocyanate self-healing elastomer has the chemical structure shown in Formula II: In the said Formula II, R 3 is , R 4 is -PEG 2000 -; The said m is 75 and n is 115; The preparation method of the said non-isocyanate self-healing elastomer is: (1) Under nitrogen protection, put urea and m-phenylenediamine into a reaction kettle, wherein the molar ratio of urea to m-phenylenediamine is 2.01:1, perform the first polymerization reaction at normal pressure (101.325 KPa) and 180 °C for 2 h to obtain a first amino-terminated prepolymer; (2) Add COOH-PEG 2000 -COOH to the first amino-terminated prepolymer obtained in step (1), perform the third polymerization reaction at 240 °C for 2 h to obtain a prepolymer with one amino end and one carboxyl end; wherein, the molar ratio of m-phenylenediamine to COOH-PEG 2000 -COOH is 1:3; (3) Reduce the pressure to 100 Pa, and perform the second polycondensation reaction on the second amino-terminated prepolymer obtained in step (2) at 250 °C for 5 h to obtain a non-isocyanate self-healing elastomer.

[0148] Example 58 On the basis of Example 56, modify R 4 to -PEG 3000 -, modify COOH-PEG 1000 -COOH to COOH-PEG 3000 -COOH, and keep other conditions unchanged to obtain a non-isocyanate self-healing elastomer.

[0149] Example 59 On the basis of Example 56, modify R 4 to -PTMG 1000 -, modify COOH-PEG 1000 -COOH to COOH-PTMG1000 -COOH, with other conditions unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0150] Example 60 Based on Example 56, R 4 is modified to -PTMG 3000 -, COOH-PEG 1000 -COOH is modified to COOH-PTMG 3000 -COOH, with other conditions unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0151] Example 61 Based on Example 56, R 4 is modified to -PDMS 1000 -, COOH-PEG 1000 -COOH is modified to COOH-PDMS 1000 -COOH, with other conditions unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0152] Example 62 Based on Example 56, R 4 is modified to -PDMS 3000 -, COOH-PEG 1000 -COOH is modified to COOH-PDMS 3000 -COOH, with other conditions unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0153] Example 63 Based on Example 56, R 4 is modified to -PDMS 5000 -, COOH-PEG 1000 -COOH is modified to COOH-PDMS 5000 -COOH, with other conditions unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0154] Example 64 Based on Example 56, R 4 is modified to -PDMS 10000 -, COOH-PEG 1000 -COOH is modified to COOH-PDMS 10000 -COOH, with other conditions unchanged, a non-isocyanate type self-healing elastomer is obtained.

[0155] Example 65 Based on Example 56, R 4 is modified to -PPG 3000 -, COOH-PEG1000 -COOH was modified to COOH-PPG 3000 -COOH, with other conditions unchanged, a non-isocyanate self-healing elastomer was obtained.

[0156] The non-isocyanate self-healing elastomers prepared in Examples 56 - 65 were subjected to performance tests according to the test method in Table 1, and the results are shown in Table 6.

[0157] Table 6 Performance data of the non-isocyanate self-healing elastomers prepared in Examples 56 - 65

[0158] Comparative Example 1 The preparation method of the non-isocyanate self-healing elastomer was as follows: (1) At 25 °C, 6.11 g of IPDI was dissolved in 10 mL of THF, and continuously mechanically stirred to obtain a mixed solution; (2) 20 mL of a THF solution containing 10 g of PPG-2000 and 4.97 g of 2,2'-diaminodiphenyl disulfide was added dropwise to the mixed solution, stirred continuously at 25 °C for 2 h, then poured into a polytetrafluoroethylene mold, placed at 25 °C for 8 h, and then placed at 90 °C for 24 h to obtain a non-isocyanate self-healing elastomer.

[0159] Comparative Example 2 The preparation method of the non-isocyanate self-healing elastomer was as follows: (1) At 25 °C, 3.67 g of IPDI was dissolved in 10 mL of THF, and continuously mechanically stirred to obtain a mixed solution; (2) 15 mL of a THF solution containing 10 g of PPG-2000 and 2.48 g of 2,2'-diaminodiphenyl disulfide was added dropwise to the mixed solution, stirred continuously at 25 °C for 2 h, then poured into a polytetrafluoroethylene mold, placed at 25 °C for 8 h, and then placed at 90 °C for 24 h to obtain a non-isocyanate self-healing elastomer.

[0160] Comparative Example 3 (1) At 25 °C, 6.11 g of IPDI was dissolved in 10 mL of THF, and continuously mechanically stirred to obtain a mixed solution; (2) 20 mL of a THF solution containing 10 g of PPG-2000 and 4.25 g of 2,2'-ethylenedianiline was added dropwise to the mixed solution, stirred continuously at 25 °C for 2 h, then poured into a polytetrafluoroethylene mold, dried at 25 °C for 8 h, and then dried at 90 °C for 24 h to obtain a non-isocyanate self-healing elastomer.

[0161] The non-isocyanate self-healing elastomers prepared in Examples 56 to 65 were subjected to performance tests according to the test method in Table 1, and the results are shown in Table 7.

[0162] Table 7 Performance data of the non-isocyanate self-healing elastomers prepared in Comparative Examples 1 to 3

[0163] As can be seen from Tables 1 to 7, the non-isocyanate self-healing elastomers prepared by the isocyanate method not only have much lower comprehensive mechanical properties than those of the present invention, but also have significantly lower self-healing ability than the non-isocyanate self-healing elastomers prepared by the non-isocyanate method using urea as the reaction carbon source in the present invention; the non-isocyanate self-healing elastomers of the present invention have excellent mechanical properties, self-healing properties and high light transmittance.

[0164] Example 66 The non-isocyanate self-healing elastomer has the chemical structure shown in Formula I: In the said Formula I, R 1 is , R 2 is ; The said x is 78 and y is 115; The preparation method of the said non-isocyanate self-healing elastomer is as follows: (1) Under nitrogen protection, urea and isophorone diamine are put into a reaction kettle, and the molar ratio of urea to isophorone diamine is 2.01:1. The first polymerization reaction is carried out at normal pressure (101.325 KPa) and 180 °C for 2 h to obtain a first amino-terminated prepolymer; (2) Polyetheramine 1000 is added to the first amino-terminated prepolymer obtained in the said step (1), and the second polymerization reaction is carried out at 240 °C for 2 h to obtain a second amino-terminated prepolymer; wherein, the molar ratio of m-phenylenediamine to polyetheramine 1000 is 1:1; (3) The pressure is reduced to 50 Pa, and the second amino-terminated prepolymer obtained in the said step (3) is subjected to the first polycondensation reaction at 250 °C for 4 h to obtain a non-isocyanate self-healing elastomer.

[0165] The nuclear magnetic resonance hydrogen spectrum of the non-isocyanate self-healing elastomer prepared in Example 66 is as Figure 1 shown, measured on a Bruker 500 MHz spectrometer. In the figure, a corresponds to the hydrogen on the ureido bond, b corresponds to the hydrogen on the soft segment polyether, and c corresponds to the hydrogen on isophorone diamine.

[0166] The non-isocyanate self-healing elastomer prepared in Example 66 was tested by Fourier transform infrared spectroscopy (FTIR), and the test wavelength range was 400 - 4000 cm -1 , and the resolution was 4 cm -1 . The results are as Figure 2 shown, Figure 2 and it is the Fourier infrared spectrogram of the non-isocyanate self-healing elastomer prepared in Example 66.

[0167] From Figure 1 and 2 , it can be seen that the non-isocyanate self-healing elastomer was successfully prepared in this invention.

[0168] The XRD spectrogram of the non-isocyanate self-healing elastomer prepared in Example 66 is as Figure 3 shown; among them, the test was carried out on an X-ray diffractometer (XRD, Ultima IV), the wavelength of Kα ray was 0.15418 nm, the accelerating voltage was 40 kV, and the emission current was 30 mA.

[0169] The transmittance of the non-isocyanate self-healing elastomer prepared in Example 66 was tested according to the method in Table 1, and the results are as Figure 4 shown, Figure 4 and it is the transmittance curve of the non-isocyanate self-healing elastomer prepared in Example 66.

[0170] From Figure 4 , it can be seen that the non-isocyanate self-healing elastomer prepared in this invention has high transmittance.

[0171] The tensile properties of the non-isocyanate self-healing elastomer prepared in Example 66 were tested according to the method in Table 1, and the results are as Figure 5 shown.

[0172] From Figure 5 , it can be seen that the non-isocyanate self-healing elastomer prepared in this invention has excellent mechanical properties.

[0173] The self-healing properties of the non-isocyanate self-healing elastomer prepared in Example 66 were tested according to the method in Table 1 as Figure 6 shown, and each curve in the figure represents the tensile properties of the non-isocyanate self-healing elastomer at different self-healing times.

[0174] From Figure 6 , it can be seen that as time increases, both its tensile strength and elongation at break increase, and after 24 h, its elongation at break and strength are close to the original properties.

[0175] As can be seen from the above examples and comparative examples, the non-isocyanate self-healing elastomer provided by the present invention has excellent self-healing ability and mechanical properties.

[0176] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A non-isocyanate self-healing elastomer, characterized in that: It has a chemical structure shown in Formula I or Formula II: Formula I; Formula II; In the formula I, R1 is at least one of an alkyl group, an alicyclic group or an aromatic group, and R2 is a polyether group, an alkylene group, an oxaalkyl group or a polysiloxane group; In the formula II, R3 is at least one of an alkyl group, an alicyclic group or an aromatic group, and R4 is a polyether group or a polysiloxane group.

2. The non-isocyanate self-healing elastomer according to claim 1, characterized in that: In the formula I, x and y are independently 40 to 120, and in the formula II, m and n are independently 40 to 120.

3. The method for preparing the non-isocyanate self-healing elastomer according to claim 1 or 2, characterized in that: The following steps are involved: (1) mixing urea and diamine to perform a first polymerization reaction to obtain a first amino-terminated prepolymer; (2) mixing the first amino-terminated prepolymer obtained in step (1) with an amino-terminated compound, and performing a second polymerization reaction to obtain a second amino-terminated prepolymer; (3) subjecting the second amino-terminated prepolymer obtained in step (2) to a first polycondensation reaction to obtain a non-isocyanate self-healing elastomer having a chemical structure of formula I.

4. The method for preparing the non-isocyanate self-healing elastomer according to claim 1 or 2, characterized in that: The following steps are involved: 1) mixing urea and diamine to perform a first polymerization reaction to obtain a first amino-terminated prepolymer; 2) subjecting the first amino-terminated prepolymer obtained in step 1) to a third polymerization reaction with a carboxyl-terminated polymer to obtain a prepolymer having an amino group at one end and a carboxyl group at the other end; 3) subjecting the prepolymer having an amino group at one end and a carboxyl group at the other end obtained in step 2) to a second polycondensation reaction to obtain a non-isocyanate self-healing elastomer having a chemical structure of formula II.

5. The preparation method according to claim 4, characterized in that: In the step 1), the molar ratio of urea to diamine is (1-2.01):

1.

6. The preparation method according to claim 4, characterized in that: In the step 1), the temperature of the first polymerization reaction is 100-200° C., and the temperature of the first polymerization reaction is 1-5 hours.

7. The preparation method according to claim 4, characterized in that: In the step 2), the carboxyl-terminated polymer is at least one of dicarboxyl-terminated polyethylene glycol, dicarboxyl-terminated polypropylene glycol, dicarboxyl-terminated polybutylene glycol and dicarboxyl-terminated polymethylsiloxane.

8. The preparation method according to claim 4, characterized in that: The temperature of the third polymerization reaction in step 2) is 180-250° C., and the temperature of the third polymerization reaction is 1-5 hours.

9. The preparation method according to claim 4, characterized in that: In the step 3), the temperature of the second polycondensation reaction is 200-250° C., the time of the second polycondensation reaction is 1-5 hours, and the pressure of the second polycondensation reaction is 10-500 Pa.

10. Application of the non-isocyanate self-healing elastomer according to claim 1 or 2 or the non-isocyanate self-healing elastomer prepared by any one of the preparation methods of claims 3 to 9 in electronic instruments, surface protection, automobiles, biomedical materials and smart materials.

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