Preparation method and application of double-end-group functionalized bionic rubber

Abstract

The invention provides a preparation method and application of double-end-group functionalized bionic rubber. The preparation method comprises the following steps: (1) preparing an isoprenyl triblock copolymer from a conjugated monomer containing side group double bonds, isoprene and a hydroxyl isoprene precursor protected by alkyl aluminum under the action of a rare earth catalyst; 2) modifying polar hydroxyl of the copolymer obtained in the step 1) by using a phospholipid compound to obtain single-ended phospholipid functionalized polyisoprene; 3) chemically modifying side group double bonds of the triblock copolymer obtained in the step 2) by using a thiol compound containing amino or / and hydroxyl through thiol-ene click to obtain amino or / and hydroxyl modified phospholipid functionalized polyisoprene; and 4) initiating anhydride ring-opening polymerization by the amino group or / and hydroxyl group introduced in the step 3), and introducing a polypeptide structure into a block at one end of the triblock copolymer to obtain the polypeptide and phospholipid double-end functionalized bionic rubber which has high tensile breaking strength and high 300% stress at definite elongation.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of synthetic rubber, and particularly relates to a preparation method of double-end group functionalized biomimetic rubber and application thereof. BACKGROUND

[0002] Natural rubber is a national basic strategic material, which is very important for industrial development, and has irreplaceable application value in the fields of aviation, aerospace, weapons, ships, nuclear power, transportation, etc., and directly affects the improvement of national industrial competitiveness.

[0003] In the synthetic rubber system, rare earth isoprene rubber is closest to natural rubber in molecular chain structure, and is currently recognized as the most promising rubber variety to replace natural rubber. However, the mechanical properties of the existing rare earth isoprene rubber, such as tensile breaking strength, breaking toughness, and modulus, still have significant gaps with natural rubber. Therefore, it is urgent to develop a double-end group functionalized biomimetic rubber with high strength and high modulus to replace natural rubber and ensure the safety of the national strategic material supply chain. SUMMARY

[0004] Therefore, the purpose of the present application is to provide a preparation method of double-end group functionalized biomimetic rubber and application thereof, which has high tensile strength and high modulus.

[0005] The present application provides a preparation method of double-end group functionalized biomimetic rubber, comprising the following steps:

[0006] 1) A conjugated monomer containing a side group double bond, isoprene monomer and an alkyl aluminum protected hydroxyl isoprene precursor are prepared into an isoprene-based tri-block copolymer with side group double bonds and polar hydroxyl groups at both ends under the action of a rare earth catalyst;

[0007] 2) The polar hydroxyl groups of the isoprene-based tri-block copolymer obtained in step 1) are modified by a phospholipid compound to obtain a single-end phospholipid functionalized polyisoprene;

[0008] 3) The side group double bonds of the single-end phospholipid functionalized polyisoprene obtained in step 2) are modified by a thiol compound containing amino or / and hydroxyl groups through thiol-ene click chemistry to obtain an amino or / and hydroxyl modified phospholipid functionalized polyisoprene;

[0009] 4) The amino or / and hydroxyl groups introduced in step 3) initiate ring-opening polymerization of N-thiocarboxylic internal anhydride, beta-amino acid-N-thiocarboxylic internal anhydride, N-carboxylic internal anhydride or / and beta-amino acid-N-carboxylic internal anhydride monomers to introduce polypeptide structures in the one-end block of the amino or / and hydroxyl modified phospholipid functionalized polyisoprene to obtain a polypeptide and phospholipid double-end functionalized biomimetic rubber.

[0010] Preferably, the conjugated monomer containing the side-group double bond in step 1) is selected from compounds with the structure shown in Formula I:

[0011] Formula I; wherein R is a C1~C20 alkyl or cyclic structure;

[0012] The alkylaluminum-protected hydroxyisoprene precursor is selected from compounds of formula II:

[0013] Formula II; wherein R is a C1~C20 alkyl or cyclic structure.

[0014] Preferably, the rare earth catalyst in step 1) includes rare earth compounds, organoaluminum compounds, and chlorides;

[0015] The rare earth compound is selected from one or more of rare earth carboxylates, rare earth acidic phosphonates, alkoxy rare earths, rare earth chloride electron donor complexes, and rare earth sulfonic acid electron donor complexes.

[0016] The organoaluminum compound is selected from trialkylaluminum and / or alkylaluminum hydride.

[0017] Preferably, the phospholipid compound in step 2) is selected from compounds having the structure of formula III or formula IV:

[0018] Formula III; Formula IV;

[0019] R1, R2, and R3 are independently selected from C1 to C20 alkyl chains or cyclic structures.

[0020] Preferably, in step 3), the thiol compound is selected from compounds of formula V or formula VI:

[0021] Formula V; Formula VI;

[0022] In formula V, R1 is selected from C1 to C20 alkyl chains or cyclic structures;

[0023] In formula VI, R2 is selected from C1 to C20 alkyl chains or cyclic structures;

[0024] In step 4), the N-thiocarboxylic acid anhydride has the structure of formula VII:

[0025] Formula VII;

[0026] β-amino acid-N-thiocarboxylic acid anhydride has the structure of formula VIII:

[0027] Formula VIII,

[0028] N-carboxylated anhydrides have the structure of formula IX:

[0029] Formula IX;

[0030] β-amino acid-N-carboxylic acid anhydride has the structure of formula X:

[0031] Formula X;

[0032] R1, R2, R3 and R4 are independently selected from alkyl chains or cyclic structures of C1 to C20.

[0033] Preferably, step 1) includes:

[0034] Under nitrogen protection, the conjugated monomer containing side group double bonds was aged at 20-80℃ for 10-240 min in the presence of a rare earth catalyst. Then, an isoprene solution was added, and the reaction was carried out at 20-80℃ for 60-360 min. After that, an alkylaluminum-protected hydroxyisoprene precursor was added, and the reaction was carried out at 20-80℃ for 60-360 min. Finally, the reaction was quenched by adding acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and then dried under vacuum at 20-60℃ to obtain an isoprene-based triblock copolymer with side group double bonds and polar hydroxyl groups at both ends.

[0035] Preferably, step 2) includes:

[0036] The isoprene triblock copolymer containing side group double bonds and polar hydroxyl groups obtained in step 1) was dissolved in a solvent, and hydroxyl activators and phospholipid compounds were added sequentially. The reaction was carried out at 0~80℃ for 2~24h. The resulting product was washed with water precipitation and dried under vacuum at 20~60℃ to obtain polyisoprene with single-terminal phospholipid functionalization.

[0037] Preferably, step 3) includes:

[0038] The single-terminal phospholipid-functionalized polyisoprene obtained in step 2) is dissolved in a solvent, and then a free radical initiator and a thiol compound are added. The mixture is reacted at 20-100°C for 0.5-4 hours to obtain amino and / or hydroxyl-modified phospholipid-functionalized polyisoprene.

[0039] Preferably, step 4) includes:

[0040] Add N-thiocarboxylic acid anhydride, β-amino acid-N-thiocarboxylic acid anhydride, N-carboxylic acid anhydride or / and β-amino acid-N-carboxylic acid anhydride monomers to the polymer solution obtained in step 3), react at 20~100℃ for 2~24 hours, wash the obtained product with ethanol precipitation, and dry it under vacuum at 20~60℃ to obtain biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0041] This invention provides a vulcanized biomimetic rubber, comprising, by mass parts, 100 parts of the double-terminal functionalized biomimetic rubber prepared by the preparation method described in the above technical solution, 0.5-5 parts of vulcanizing agent, 0.2-5 parts of vulcanization accelerator, 2-10 parts of zinc oxide, 1-5 parts of stearic acid, 0.5-5 parts of antioxidant, and 0.5-5 parts of anti-aging agent.

[0042] This invention provides a method for preparing bi-terminal functionalized biomimetic rubber, comprising the following steps: 1) preparing an isoprene-based triblock copolymer with side-chain double bonds in the form of a conjugated monomer containing side-chain double bonds, isoprene, and an alkylaluminum-protected hydroxyl isoprene precursor under the action of a rare earth catalyst; 2) modifying the polar hydroxyl groups of the isoprene-based triblock copolymer obtained in step 1) with a phospholipid compound to obtain a phospholipid-functionalized polyisoprene; 3) passing a thiol compound containing amino and / or hydroxyl groups through a mercapto-olefin... Click on the side double bonds of the single-terminal phospholipid-functionalized polyisoprene obtained in step 2) of chemical modification to obtain amino and / or hydroxyl-modified phospholipid-functionalized polyisoprene; 4) Initiate ring-opening polymerization of N-thiocarboxylic acid anhydride, β-amino acid-N-thiocarboxylic acid anhydride, N-carboxylic acid anhydride or / and β-amino acid-N-carboxylic acid anhydride monomers using the amino and / or hydroxyl-modified phospholipid-functionalized polyisoprene, introducing a polypeptide structure into one end block of the amino and / or hydroxyl-modified phospholipid-functionalized polyisoprene, to obtain a biomimetic rubber with both polypeptide and phospholipid end functionalization. This invention prepares a biomimetic rubber with both polypeptide and phospholipid end functionalization by simulating the fine molecular structure of natural rubber. The obtained biomimetic rubber has high tensile breaking strength (27~28MPa) and high 300% tensile stress (2.1~2.2MPa). These properties are significantly better than conventional rare earth isoprene rubber and comparable to natural rubber. The biomimetic rubber prepared by this invention is expected to replace natural rubber and be used in high-end fields such as aircraft tires and high-end seals. Detailed Implementation

[0043] This invention provides a method for preparing bi-terminal functionalized biomimetic rubber, comprising the following steps:

[0044] 1) An isoprene-based triblock copolymer with side-chain double bonds in the first and last segments and polar hydroxyl groups in the first and last segments is prepared by using a rare earth catalyst to prepare a conjugated monomer containing side-chain double bonds, isoprene and alkyl aluminum protected hydroxy isoprene precursor.

[0045] 2) Modify the polar hydroxyl groups of the isoprene triblock copolymer obtained in step 1) with phospholipid compounds to obtain polyisoprene with single-ended phospholipid functionalization.

[0046] 3) The side double bonds of the single-terminal phospholipid-functionalized polyisoprene obtained in step 2) are modified by thiol compounds containing amino or / and hydroxyl groups through mercapto-olefin click chemistry to obtain phospholipid-functionalized polyisoprene modified with amino or / and hydroxyl groups.

[0047] 4) The amino and / or hydroxyl groups introduced in step 3) initiate the ring-opening polymerization of N-thiocarboxylic anhydride, β-amino acid-N-thiocarboxylic anhydride, N-carboxylic anhydride or / and β-amino acid-N-carboxylic anhydride monomers, and introduce a polypeptide structure into one end block of phospholipid-functionalized polyisoprene modified with amino and / or hydroxyl groups, to obtain a biomimetic rubber with both polypeptide and phospholipid end functionalization.

[0048] This invention designs and synthesizes bi-terminated functionalized polyisoprene by mimicking the fine molecular structure of natural rubber. At the same time, it introduces peptides and phospholipids to simulate the intermolecular interactions of non-olefin components (proteins, peptides, phospholipids, etc.) to prepare a biomimetic rubber with high strength and high tensile stress. It is expected to replace natural rubber in high-end fields such as aircraft tires and high-end seals.

[0049] This invention prepares isoprene-based triblock copolymers with side-group double bonds in the form of a conjugated monomer containing side-group double bonds, isoprene, and an alkylaluminum-protected hydroxyisoprene precursor under the action of a rare earth catalyst.

[0050] In this invention, the conjugated monomer containing the side-group double bond in step 1) is selected from compounds with the structure shown in Formula I:

[0051] Formula I; in Formula I, R is a C1~C20 alkyl or cyclic structure; wherein, the cyclic structure is such as a benzene ring, cycloalkenyl or cycloalkyl, etc.

[0052] In this invention, the alkylaluminum-protected hydroxyisoprene precursor is selected from compounds of formula II:

[0053] Formula II; in Formula II, R is a C1~C20 alkyl or cyclic structure.

[0054] In this invention, the rare earth catalyst mainly comprises rare earth compounds, organoaluminum compounds, and chlorides; the rare earth compounds are selected from one or more of rare earth carboxylates, rare earth acidic phosphonates, alkoxy rare earths, rare earth chloride electron donor complexes, and rare earth sulfonate electron donor complexes; preferably neodymium neodecanoate (Nd(vers)3), neodymium isooctanoate (Nd(EHA)3), neodymium naphthenate (Nd(naph)3), and (2-ethylhexyl)phosphonate (Nd(P)3). 204 3) Neodymium mono-2-ethylhexyl (2-ethylhexyl)phosphonate (Nd(P) 5073) Ethoxyneodymium, n-propoxyneodymium, isopropoxyneodymium, neodymium chloride isopropanol (NdCl3·3) i PrOH), NdCl3·3TBP, Nd(CF3SO3)3·3TBP, and Nd(C)2N,N-dimethylformamide benzenesulfonate (Nd(C)2N,N-dimethylformamide benzenesulfonate) 18 H 29 One or more of SO3(3·3C3H7NO).

[0055] The organoaluminum compound is selected from trialkylaluminum and / or alkylaluminum hydride; preferably from one or more of triisobutylaluminum (Al(i-Bu)3), diisobutylaluminum hydride (Al(i-Bu)2H), triethylaluminum (AlEt3), diethylaluminum hydride (AlEt2H), trioctylaluminum (Al(oct)3) and trimethylaluminum (AlMe3).

[0056] The chloride is preferably selected from diisobutylaluminum chloride (Al(i-Bu)₂Cl), diethylaluminum chloride (AlEt₂Cl), sesquiethylaluminum (Al₂Et₃Cl₃), tert-butyl chloride (t-BuCl), benzyl chloride (BzCl), allyl chloride (H₂C=CHCH₂Cl), and chloromethylsilane (Me). 4-n SiCl n One or more of the following: n=1-3, silicon tetrachloride (SiCl4), and tetrachloromethane (CCl4).

[0057] The molar ratio of rare earth compounds, organoaluminum compounds and chlorides in the rare earth catalyst of this invention is 1:(5~30):(1~4).

[0058] Step 1) in this invention includes:

[0059] Under nitrogen protection, the conjugated monomer containing side group double bonds was aged at 20-80℃ for 10-240 min in the presence of a rare earth catalyst. Then, an isoprene solution was added, and the reaction was carried out at 20-80℃ for 60-360 min. After that, an alkylaluminum-protected hydroxyisoprene precursor was added, and the reaction was carried out at 20-80℃ for 60-360 min. Finally, the reaction was quenched by adding acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and then dried under vacuum at 20-60℃ to obtain an isoprene-based triblock copolymer with side group double bonds and polar hydroxyl groups at both ends.

[0060] The solvent in the isoprene solution described in this invention is selected from one or more of tetrahydrofuran, chloroform, dichloromethane, n-hexane, and toluene.

[0061] The molar ratio of the conjugated monomer containing side double bonds, the rare earth catalyst, the isoprene, and the alkylaluminum protected hydroxyisoprene precursor in this invention is (10~50):1:(200~10000):(10~50).

[0062] This invention utilizes phospholipid compounds to modify the polar hydroxyl groups of the isoprene triblock copolymer obtained in step 1) to obtain polyisoprene with single-ended phospholipid functionalization.

[0063] In this invention, the phospholipid compound in step 2) is selected from compounds having the structure of formula III or formula IV:

[0064] Formula III; Formula IV;

[0065] In Formula III, R1 is selected from C1-C20 alkyl chains or cyclic structures; in Formula IV, R2 and R3 are independently selected from C1-C20 alkyl chains or cyclic structures. The phospholipid compounds described in this invention are more preferably selected from one or more of ethanolamine phosphate, 3-aminopropyl dihydrogen phosphate, 4-aminophenyl phosphate, 4-aminophenylphosphocholine, 2-aminoethyl (2-(trimethylamino)ethyl) phosphate, and 11-aminoundecyl (2-(trimethylammonium)ethyl) phosphate.

[0066] Step 2) in this invention preferably includes:

[0067] The isoprene triblock copolymer containing side group double bonds and polar hydroxyl groups obtained in step 1) was dissolved in a solvent, and hydroxyl activators and phospholipid compounds were added sequentially. The reaction was carried out at 0~80℃ for 2~24h. The resulting product was washed with water precipitation and dried under vacuum at 20~60℃ to obtain polyisoprene with single-terminal phospholipid functionalization.

[0068] The solvent used in step 2) of this invention is selected from one or more of tetrahydrofuran, chloroform, dichloromethane, n-hexane and toluene.

[0069] The activator used in step 2) of this invention is selected from one or more of carbodiimide compounds, onium salts, urea salts, and trifluoromethanesulfonates, preferably from dicyclohexylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, 1-hydroxybenzotriazole, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine hydrochloride, 4-N,N-dimethylpyridine, 1-[bis(dimethylaminopropyl)carbodiimide, etc.] One or more of the following: [dimethylamino)methylene]-1H-benzotriazolium 3-oxide hexafluorophosphate, 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate, 1-[bis(dimethylamino)methylene]-1H-benzotriazolium 3-oxide tetrafluoroborate, trifluoromethanesulfonate diphenylamine salt, and pentafluoroaniline trifluoromethanesulfonate.

[0070] In step 2) of this invention, the molar ratio of isoprene triblock copolymer, activator and phospholipid compound is 1:(10~60):(10~60).

[0071] This invention modifies the side double bonds of the single-terminal phospholipid-functionalized polyisoprene obtained by the thiol compound containing amino or / and hydroxyl groups through the mercapto-alkene click chemical modification step 2), thereby obtaining phospholipid-functionalized polyisoprene modified with amino or / and hydroxyl groups.

[0072] In this invention, the amino-containing thiol compound has the structure of formula V: Formula V; in Formula V, R1 is selected from C1-C20 alkyl chains or cyclic structures. The hydroxyl-containing thiol compound has the compounds shown in Formula VI: Formula VI; in Formula VI, R2 is selected from C1-C20 alkyl chains or cyclic structures. The thiol compounds described in this invention are preferably selected from 6-aminohexanethiol, 7-amino-1-heptanethiol, 2-aminoethanethiol, 2-[(3-amino-2,2-dimethylpropyl)amino]ethanethiol, 2-amino-1-naphthylthiol, 3-amino-4-methylbenzylthiol, 2-amino-6-methoxy-benzylthiol, 3,4-diaminobenzylthiol, 2-(3-aminopropylamino)ethanethiol, 2-aminothiazolyl-5-thiol, m-aminobenzylthiophenol, 4-amino-benzylthiol, 2-amino-6-methylpyridine-3-thiol, 3-amino-4-methylbenzylthiol, hydroxylamine-diethylene glycol-mercapto, 3... One or more of the following: 1-mercapto-1-propanol, 4-mercapto-1-butanol, 3-thio-1-hexanol, 2-mercaptobenzyl alcohol, mercapto-PEG4-ol, 8-mercapto-1-octanol, 9-mercapto-1-nonanol, 4-mercaptobenzyl alcohol, 3-mercapto-2-butanol, 2-mercaptoethoxyethanol, 16-mercaptohexadecane-1-ol, 3-mercapto-3-methylbutylol, 3-mercapto-2-methylpentanol, 2-mercapto-2-methyl-1-pentanol, 3-mercapto-cyclohexanol, 2-amino-3-mercapto-1-propanol, 2-(1-mercaptoethyl)naphth-1-ol, and 4-(6-mercaptohexoxy)benzyl alcohol.

[0073] In this invention, the single-terminal phospholipid-functionalized polyisoprene obtained in step 2) is dissolved in a solvent, and then a free radical initiator and a thiol compound are added. The mixture is reacted at 20-100°C for 0.5-4 hours to obtain amino- and / or hydroxyl-modified phospholipid-functionalized polyisoprene.

[0074] In this invention, the solvent used to dissolve the single-terminal phospholipid-functionalized polyisoprene is selected from one or more of tetrahydrofuran, chloroform, dichloromethane, n-hexane, and toluene; the free radical initiator is selected from one or more of azo compounds, organic peroxides, acetophenone derivatives, acylphosphine oxides, α-aminoketones, and organometallic compounds, more preferably from 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2-methylpropanediamine) dihydrochloride, benzoyl peroxide, dicumyl peroxide, and 2-hydroxy-2-methyl-1- One or more of the following: phenylacetone, 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2,2-dimethoxy-2-phenylethyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, benzoyltrimethylgermanane, and tetrakis(2,4,6-trimethylbenzoyl)stannane. The initiation method is thermal initiation at 50–100 °C or photoinitiation at 200–550 nm.

[0075] In step 3) of the present invention, the molar ratio of the single-terminal phospholipid-functionalized polyisoprene, the free radical initiator and the thiol compound is 1:(0.005~1):(10~60), preferably 1:(0.5~1):(20~50).

[0076] This invention involves the introduction of amino and / or hydroxyl groups in step 3) to initiate the ring-opening polymerization of one or more monomers of N-thiocarboxylic anhydride, β-amino acid-N-thiocarboxylic anhydride, N-carboxylic anhydride, or / and β-amino acid-N-carboxylic anhydride, thereby introducing a polypeptide structure into one end block of phospholipid-functionalized polyisoprene modified with amino and / or hydroxyl groups, to obtain a biomimetic rubber with both polypeptide and phospholipid end functionalization.

[0077] In step 4) of this invention, the N-thiocarboxylic acid anhydride has the structure of formula VII:

[0078] Formula VII;

[0079] β-amino acid-N-thiocarboxylic acid anhydride has the structure of formula VIII:

[0080] Formula VIII;

[0081] N-carboxylated anhydrides have the structure of formula IX:

[0082] Formula IX;

[0083] β-amino acid-N-carboxylic acid anhydride has the structure of formula X:

[0084] Formula X;

[0085] R1, R2, R3 and R4 are independently selected from alkyl chains or cyclic structures of C1 to C20.

[0086] The compounds represented by formulas VII, VIII, IX, and X in this invention are preferably derived from L-alanine-N-carboxylic acid anhydride, D-alanine-N-carboxylic acid anhydride, L-aspartic acid-4-benzyl ester-N-carboxylic acid anhydride, L-serine-N-carboxylic acid anhydride, L-tryptophan-N-carboxylic acid anhydride, L-valine-N-carboxylic acid anhydride, Nε-benzyloxycarbonyl-L-lysine anhydride, phenylalanine-N-carboxylic acid anhydride, indigo anhydride, 4-carboxyinoid anhydride, β-tyrosine-N-carboxylic acid anhydride, L-valine-N-thiocarboxylic acid anhydride, and β-(4-methylphenyl)alanine-N-thiocarboxylic acid anhydride.

[0087] In step 4) of this invention, the molar ratio of the amino- or / and hydroxyl-modified phospholipid-functionalized polyisoprene to N-thiocarboxylic acid anhydride, β-amino acid-N-thiocarboxylic acid anhydride, N-carboxylic acid anhydride or / and β-amino acid-N-carboxylic acid anhydride monomers is 1:1 to 200.

[0088] The present invention uses steps 1)-4) above to mimic the fine molecular structure of natural rubber, and the resulting biomimetic rubber with double-terminal functionalization of polypeptides and phospholipids has a polyisoprene segment cis degree ≥96%.

[0089] The present invention also provides a vulcanized biomimetic rubber, comprising, by weight, 100 parts of the double-terminal functionalized biomimetic rubber prepared by the method described in the above technical solution, 0.5-5 parts of vulcanizing agent, 0.2-5 parts of vulcanization accelerator, 2-10 parts of zinc oxide, 1-5 parts of stearic acid, 0.5-5 parts of antioxidant, and 0.5-5 parts of anti-aging agent.

[0090] The vulcanizing agent described in this invention is sulfur, resin-based vulcanizing agent, thiuram, or peroxide, preferably one of sulfur, tert-butylphenol formaldehyde resin, tert-octylphenol formaldehyde resin, tetramethylthiuram disulfide, tetramethyl bispentimethylene thiuram tetrasulfide, tetraethylthiuram disulfide, 4-(2-benzothiazolyl dithio)morpholine, di-tert-butyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-(di-tert-butylperoxy)hexane, 1,1-di-tert-butylperoxy-3,3,5-trimethylcyclohexane, benzoyl peroxide, or tert-butyl perbenzoate.

[0091] The vulcanization accelerator, zinc oxide, stearic acid, antioxidant, and anti-aging agent are all additives.

[0092] The biomimetic rubber with dual-terminal functionalization of polypeptides and phospholipids obtained in this invention is vulcanized by the following method: the biomimetic rubber, vulcanizing agent and additives are mixed by two-roll milling, and then vulcanized at a high temperature of 120~160℃ to obtain vulcanized biomimetic rubber.

[0093] The biomimetic rubber obtained by this invention exhibits high strength and high tensile stress comparable to natural rubber after vulcanization.

[0094] To further illustrate the present invention, the following detailed description, in conjunction with embodiments, of a method for preparing a dual-terminal functionalized biomimetic rubber and its application, should not be construed as limiting the scope of protection of the present invention.

[0095] The conjugated monomers containing side-chain double bonds used in the embodiments of the present invention were synthesized according to the method reported in the literature (Liu, RSH, Hammond, GS, 1967. Journal of the American Chemical Society 89(19), 4936-4944.).

[0096] Example 1

[0097] Under nitrogen protection, neodymium isooctanoate (Nd(EHA)3, 0.18 mmol), 3-methylene-1,8-nonadiene (3.6 mmol), diisobutylaluminum hydride (Al(i-Bu)2H, 1.8 mmol), and sesquiethylaluminum (Al2Et3Cl3, 0.18 mmol) were sequentially added to a sealed glass bottle and aged at 25 °C for 30 min. Then, 400 mL of hexane solution containing isoprene (1.44 mol) was added, and the reaction was continued at 25 °C for 240 min. Subsequently, 6-methylene-7-octen-1-ol (5.4 mmol) protected by alkylaluminum was added, and the reaction was continued at 25 °C for 240 min. Finally, the reaction was quenched dropwise with acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 ml of tetrahydrofuran, and dicyclohexylcarbodiimide (5.4 mmol), 1-hydroxybenzotriazole (5.4 mmol), and 3-aminopropyl dihydrogen phosphate (5.4 mmol) were added sequentially. The reaction was carried out at 25 °C for 4 h. The resulting product was washed with water precipitation and dried under vacuum at 40 °C to obtain phospholipid-functionalized polyisoprene. The obtained phospholipid-functionalized polyisoprene was dissolved in 400 ml of toluene, and benzoyl peroxide (0.09 mmol) and 6-aminohexanethiol (3.6 mmol) were added to the polymer solution. The reaction was carried out at 60 °C for 2 h. Then, L-valine-N-thiocarboxylic acid anhydride (18 mmol) was added to the polymer solution, and the reaction was carried out at 50 °C for 12 h. The resulting product was washed with ethanol precipitation and dried under vacuum at 25 °C to obtain a biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0098] 100 parts of biomimetic rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0099] Example 2

[0100] Under nitrogen protection, neodymium mono-2-ethylhexyl (2-ethylhexyl)phosphonate (Nd(P) 507 3-Methylene-1,9-decadiene (5.4 mmol), triisobutylaluminum (Al(i-Bu)3, 3.6 mmol), and diisobutylaluminum chloride (Al(i-Bu)2Cl, 0.36 mmol) were sequentially added to a sealed glass bottle and aged at 25 °C for 40 min. Then, 400 mL of hexane solution containing isoprene (1.26 mol) was added, and the reaction was continued at 25 °C for 240 min. Subsequently, alkylaluminum-protected 6-methylene-7-octen-1-ol (5.4 mmol) was added, and the reaction was continued at 25 °C for 240 min. Finally, acidified ethanol was added dropwise to quench the reaction. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 ml of tetrahydrofuran, and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (5.4 mmol), 1-hydroxybenzotriazole (5.4 mmol), and ethanolamine phosphate (5.4 mmol) were added sequentially. The reaction was carried out at 25 °C for 4 h. The resulting product was washed with water precipitation and dried under vacuum at 40 °C to obtain phospholipid-functionalized polyisoprene. The obtained phospholipid-functionalized polyisoprene was dissolved in 400 ml of toluene, and benzoyl peroxide (0.09 mmol) and 7-amino-1-heptathiol (3.6 mmol) were added to the polymer solution. The reaction was carried out at 80 °C for 3 h. Then, β-(4-methylphenyl)alanine-N-thiocarboxylic acid anhydride (18 mmol) was added to the polymer solution, and the reaction was carried out at 50 °C for 12 h. The resulting product was washed with ethanol precipitation and dried under vacuum at 25 °C to obtain a biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0101] 100 parts of biomimetic rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0102] Example 3

[0103] Under nitrogen protection, neodymium neodecanoate (Nd(vers)3, 0.18 mmol), 3-methylene-1,9-decadiene (3.6 mmol), triisobutylaluminum (Al(i-Bu)3, 3.6 mmol), and diisobutylaluminum chloride (Al(i-Bu)2Cl, 0.36 mmol) were sequentially added to a sealed glass bottle and aged at 25 °C for 40 min. Then, 400 mL of hexane solution containing isoprene (0.72 mol) was added, and the reaction was continued at 25 °C for 240 min. Subsequently, 7-methylene-8-nonen-1-ol (7.2 mmol) protected by alkylaluminum was added, and the reaction was continued at 25 °C for 240 min. Finally, the reaction was quenched dropwise with acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 ml of tetrahydrofuran, and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (5.4 mmol), 1-hydroxybenzotriazole (5.4 mmol), and 4-aminophenylphosphine (5.4 mmol) were added sequentially. The reaction was carried out at 25 °C for 4 h. The resulting product was washed with water precipitation and dried under vacuum at 40 °C to obtain phospholipid-terminated polyisoprene. The obtained phospholipid-terminated polyisoprene was dissolved in 400 ml of toluene, and 2,2'-azobis(isobutyronitrile) (0.09 mmol) and 2-aminoethanethiol (3.6 mmol) were added to the polymer solution. The reaction was carried out at 80 °C for 3 h. Then, L-valine-N-thiocarboxylic acid anhydride (9 mmol) was added to the polymer solution, and the reaction was carried out at 50 °C for 8 h. The resulting product was washed with ethanol precipitation and dried under vacuum at 25 °C to obtain a biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0104] 100 parts of biomimetic rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0105] Example 4

[0106] Under nitrogen protection, neodymium (2-ethylhexyl)phosphonate (Nd(P)) 2043-Methylene-1,9-decadiene (3.6 mmol), trioctylaluminum (Al(oct)3, 3.6 mmol), and diethylaluminum chloride (AlEt2Cl, 0.36 mmol) were sequentially added to a sealed glass bottle and aged at 50 °C for 50 min. Then, 400 mL of hexane solution containing isoprene (1.26 mol) was added, and the reaction was continued at 50 °C for 300 min. Subsequently, 7-methylene-8-nonen-1-ol (7.2 mmol) protected by alkylaluminum was added, and the reaction was continued at 25 °C for 240 min. Finally, the reaction was quenched dropwise with acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 mL of tetrahydrofuran, and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (5.4 mmol), 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine hydrochloride (5.4 mmol) and 4-aminophenylphosphocholine (5.4 mmol) were added sequentially. The reaction was carried out at 50 °C for 4 h. The resulting product was washed with water precipitation and dried under vacuum at 40 °C to obtain phospholipid-functionalized polyisoprene. The obtained phospholipid-functionalized polyisoprene was dissolved in 400 mL of toluene, and 2,2'-azobis(isobutyronitrile) (0.09 mmol) and 3-mercapto-1-propanol (3.6 mmol) were added to the polymer solution. The reaction was carried out at 70 °C for 3 h. Then, L-aspartic acid-4-benzyl ester-N-carboxycyclic anhydride (9 mmol) was added to the polymer solution, and the reaction was carried out at 50 °C for 8 h. The resulting product was precipitated and washed with ethanol, and then vacuum dried at 25°C to obtain a biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0107] 100 parts of biomimetic rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0108] Example 5:

[0109] Under nitrogen protection, neodymium naphthenate (Nd(naph)3, 0.18 mmol), 3-methylene-1,9-decadiene (3.6 mmol), triethylaluminum (AlEt3, 3.6 mmol), and diethylaluminum chloride (AlEt2Cl, 0.36 mmol) were sequentially added to a sealed glass bottle and aged at 50 °C for 50 min. Then, 400 mL of hexane solution containing isoprene (1.08 mol) was added, and the reaction was continued at 50 °C for 300 min. Next, 7-methylene-8-nonen-1-ol (7.2 mmol) protected with alkylaluminum was added, and the reaction was continued at 25 °C for 240 min. Finally, the reaction was quenched dropwise with acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 ml of tetrahydrofuran, and 1-[bis(dimethylamino)methylene]-1H-benzotriazolium 3-oxide hexafluorophosphate (7.2 mmol) and 2-aminoethyl (2-(trimethylamino)ethyl) phosphate (7.2 mmol) were added sequentially. The reaction was carried out at 50 °C for 4 h. The resulting product was washed with water precipitation and dried under vacuum at 40 °C to obtain phospholipid-functionalized polyisoprene. The obtained phospholipid-functionalized polyisoprene was dissolved in 400 ml of toluene, and benzoyl peroxide (0.09 mmol) and 4-mercapto-1-butanol (3.6 mmol) were added to the polymer solution. The reaction was carried out at 70 °C for 3 h. Then, L-serine-N-carboxycyclic anhydride (3.6 mmol) was added to the polymer solution, and the reaction was carried out at 50 °C for 8 h. The resulting product was washed with ethanol precipitation and dried under vacuum at 25 °C to obtain a biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0110] 100 parts of biomimetic rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0111] Example 6

[0112] Under nitrogen protection, neodymium chloride isopropanol (NdCl3·3) iPrOH (0.18 mmol), 3-methylene-1,9-decadiene (1.8 mmol), diethylaluminum hydride (AlEt2H, 2.7 mmol), and diethylaluminum chloride (AlEt2Cl, 0.36 mmol) were sequentially added to a sealed glass bottle and aged at 50 °C for 50 min. Then, 400 mL of hexane solution containing isoprene (1.44 mol) was added, and the reaction was continued at 50 °C for 360 min. Subsequently, 7-methylene-8-nonen-1-ol (7.2 mmol) protected by alkylaluminum was added, and the reaction was continued at 25 °C for 240 min. Finally, the reaction was quenched dropwise with acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 mL of tetrahydrofuran, and 1-[bis(dimethylamino)methylene]-1H-benzotriazolium 3-oxide hexafluorophosphate (7.2 mmol) and 11-aminoundecyl(2-(trimethylammonium)ethyl) phosphate (7.2 mmol) were added sequentially. The reaction was carried out at 50 °C for 4 h. The resulting product was washed with water precipitation and dried under vacuum at 40 °C to obtain phospholipid-terminated polyisoprene. The obtained phospholipid-terminated polyisoprene was dissolved in 400 mL of toluene, and dicumyl peroxide (0.09 mmol) and 3-thio-1-hexanol (1.8 mmol) were added to the polymer solution. The reaction was carried out at 100 °C for 3 h. Then, Nε-benzyloxycarbonyl-L-lysine cyclic anhydride (18 mmol) was added to the polymer solution, and the reaction was carried out at 50 °C for 8 h. The resulting product was precipitated and washed with ethanol, and then vacuum dried at 25°C to obtain a biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0113] 100 parts of biomimetic rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0114] Example 7

[0115] Under nitrogen protection, neodymium chloride tributyl phosphate (NdCl3·3TBP, 0.18 mmol), 3-methylene-1,5-hexadiene (9 mmol), triisobutylaluminum (Al(i-Bu)3, 5.4 mmol), and chloromethylsilane (Me) were added. 4-n SiCl nA mixture of 1-[bis(dimethylamino)methylene]-1H-benzotriazine 3-oxide hexafluorophosphate (9 mmol) and 3-aminopropyl dihydrogen phosphate (9 mmol) was added sequentially to a sealed glass bottle and aged at 50 °C for 50 min. Then, 400 mL of hexane solution containing 1.8 mol of isoprene was added, and the reaction was continued at 50 °C for 360 min. Following this, 9 mmol of alkylaluminum-protected 7-methylene-8-nonen-1-ol was added, and the reaction was continued at 25 °C for 240 min. Finally, acidified ethanol was added dropwise to quench the reaction. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 mL of tetrahydrofuran, and 9 mmol of 1-[bis(dimethylamino)methylene]-1H-benzotriazine 3-oxide hexafluorophosphate and 9 mmol of 3-aminopropyl dihydrogen phosphate were added sequentially, and the reaction was carried out at 50 °C for 4 h. The obtained product was washed with water after precipitation and dried under vacuum at 40 °C to obtain phospholipid-terminated polyisoprene. The obtained phospholipid-terminated polyisoprene was dissolved in 400 mL of toluene. 2,2-Dimethoxy-2-phenylethyl ketone (0.09 mmol) and 2-mercaptobenzyl alcohol (9 mmol) were added to the polymer solution, and the reaction was carried out at 25 °C for 4 h under 340 nm UV irradiation. Then, phenylalanine-N-carboxylic acid anhydride (36 mmol) was added to the polymer solution, and the reaction was carried out at 50 °C for 8 h. The obtained product was washed with ethanol after precipitation and dried under vacuum at 25 °C to obtain a biomimetic rubber with both peptide and phospholipid-terminated functionalizations.

[0116] 100 parts of biomimetic rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0117] Example 8

[0118] Under nitrogen protection, neodymium chloride tributyl phosphate (NdCl3·3TBP, 0.18 mmol), 3-methylene-1,5-hexadiene (9 mmol), triisobutylaluminum (Al(i-Bu)3, 5.4 mmol), and chloromethylsilane (Me) were added. 4-n SiCl nThe following solutions were added sequentially: n=1-3, 0.72 mmol) were added to a sealed glass bottle and aged at 50 °C for 50 min; then, 400 ml of hexane solution containing 1.8 mol of isoprene was added and the reaction was continued at 50 °C for 360 min; subsequently, 9 mmol of alkylaluminum-protected 7-methylene-8-nonen-1-ol was added and the reaction was continued at 25 °C for 240 min; finally, acidified ethanol was added dropwise to quench the reaction. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 ml of tetrahydrofuran, and 9 mmol of 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate and 9 mmol of 4-aminophenyl phosphate were added sequentially and the reaction was carried out at 50 °C for 4 h. The obtained product was washed with water after precipitation and dried under vacuum at 40 °C to obtain phospholipid-terminated polyisoprene. The obtained phospholipid-terminated polyisoprene was dissolved in 400 ml of toluene. 0.18 mmol of 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone and 9-mercapto-1-nonanol (9 mmol) were added to the polymer solution, and the reaction was carried out at 25 °C for 4 h under 250 nm UV irradiation. Then, 36 mmol of β-tyrosine-N-carboxycyclic anhydride was added to the polymer solution, and the reaction was carried out at 50 °C for 8 h. The obtained product was washed with ethanol after precipitation and dried under vacuum at 25 °C to obtain a biomimetic rubber with both peptide and phospholipid-terminated functionalizations.

[0119] 100 parts of biomimetic rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0120] Example 9

[0121] Under nitrogen protection, neodymium neodecanoate (Nd(vers)3, 0.18 mmol), 3-methylene-1,5-hexadiene (9 mmol), triisobutylaluminum (Al(i-Bu)3, 5.4 mmol), and diisobutylaluminum chloride (Al(i-Bu)2Cl, 0.72 mmol) were sequentially added to a sealed glass bottle and aged at 50 °C for 30 min. Then, 400 mL of hexane solution containing 1.8 mol of isoprene was added, and the reaction was continued at 50 °C for 360 min. Subsequently, 8-methylene-9-decen-1-ol (9 mmol) protected by alkylaluminum was added, and the reaction was continued at 25 °C for 240 min. Finally, the reaction was quenched dropwise with acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 ml of tetrahydrofuran, and dicyclohexylcarbodiimide (9 mmol), 4-N,N-dimethylpyridine (9 mmol), and 2-aminoethyl (2-(trimethylamino)ethyl) phosphate (9 mmol) were added sequentially. The reaction was carried out at 50 °C for 4 h. The resulting product was washed with water precipitation and dried under vacuum at 40 °C to obtain phospholipid-functionalized polyisoprene. The obtained phospholipid-functionalized polyisoprene was dissolved in 400 ml of toluene, and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone (0.18 mmol) and 2-mercaptoethoxyethanol (9 mmol) were added to the polymer solution. The reaction was carried out under 250 nm UV irradiation at 25 °C for 4 h. Then, indocyanine anhydride (18 mmol) was added to the polymer solution, and the reaction was carried out at 80 °C for 2 h. The resulting product was washed with ethanol precipitation and dried under vacuum at 25 °C to obtain a biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0122] 100 parts of biomimetic rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0123] Example 10

[0124] Under nitrogen protection, neodymium neodecanoate (Nd(vers)3, 0.18 mmol), 3-methylene-1,5-hexadiene (1.8 mmol), triisobutylaluminum (Al(i-Bu)3, 3.6 mmol), and diisobutylaluminum chloride (Al(i-Bu)2Cl, 0.36 mmol) were sequentially added to a sealed glass bottle and aged at 50 °C for 30 min. Then, 400 mL of hexane solution containing isoprene (1.8 mol) was added, and the reaction was continued at 50 °C for 360 min. Subsequently, 8-methylene-9-decen-1-ol (9 mmol) protected by alkylaluminum was added, and the reaction was continued at 25 °C for 240 min. Finally, the reaction was quenched dropwise with acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 mL of tetrahydrofuran, and dicyclohexylcarbodiimide (9 mmol), 4-N,N-dimethylpyridine (9 mmol), and 4-aminophenylphosphocholine (9 mmol) were added sequentially. The reaction was carried out at 50 °C for 4 h. The resulting product was washed with water precipitation and dried under vacuum at 40 °C to obtain phospholipid-functionalized polyisoprene. The obtained phospholipid-functionalized polyisoprene was dissolved in 400 mL of toluene, and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone (0.09 mmol) and 2-(1-mercaptoethyl)naphthalene-1-ol (1.8 mmol) were added to the polymer solution. The reaction was carried out at 25 °C for 4 h under 250 nm UV irradiation. Then, β-tyrosine-N-carboxylic anhydride (36 mmol) was added to the polymer solution, and the reaction was carried out at 80 °C for 8 h. The resulting product was precipitated and washed with ethanol, and then vacuum dried at 25°C to obtain a biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0125] 100 parts of biomimetic rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0126] Example 11

[0127] Under nitrogen protection, neodymium neodecanoate (Nd(vers)3, 0.18 mmol), 3-methylene-1,5-hexadiene (3.6 mmol), triisobutylaluminum (Al(i-Bu)3, 3.6 mmol), and diisobutylaluminum chloride (Al(i-Bu)2Cl, 0.36 mmol) were sequentially added to a sealed glass bottle and aged at 50 °C for 30 min. Then, 400 mL of hexane solution containing isoprene (1.26 mol) was added, and the reaction was continued at 50 °C for 360 min. Subsequently, 8-methylene-9-decen-1-ol (1.8 mmol) protected by alkylaluminum was added, and the reaction was continued at 25 °C for 240 min. Finally, the reaction was quenched dropwise with acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 ml of tetrahydrofuran, and dicyclohexylcarbodiimide (3.6 mmol), 4-N,N-dimethylpyridine (3.6 mmol), and 4-aminophenylphosphocholine (1.8 mmol) were added sequentially. The reaction was carried out at 50 °C for 4 h. The resulting product was washed with water and dried under vacuum at 40 °C to obtain phospholipid-functionalized polyisoprene. The obtained phospholipid-functionalized polyisoprene was dissolved in 400 ml of toluene, and 2,2'-azobis(isobutyronitrile) (0.09 mmol) and 2-aminothiazol-5-thiol (1.8 mmol) were added to the polymer solution. The reaction was carried out at 70 °C for 4 h. Then, β-(4-methylphenyl)alanine-N-thiocarboxylic acid anhydride (36 mmol) was added to the polymer solution, and the reaction was carried out at 80 °C for 8 h. The resulting product was washed with ethanol and dried under vacuum at 25 °C to obtain a biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0128] 100 parts of biomimetic rubber, 3 parts of di-tert-butyl peroxide, 3 parts of N-tert-butyl-2-benzothiazole sulfenamide, 8 parts of zinc oxide, 2 parts of stearic acid, 2 parts of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 3 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0129] Example 12

[0130] Under nitrogen protection, neodymium neodecanoate (Nd(vers)3, 0.18 mmol), 3-methylene-1,5-hexadiene (1.8 mmol), triisobutylaluminum (Al(i-Bu)3, 3.6 mmol), and diisobutylaluminum chloride (Al(i-Bu)2Cl, 0.36 mmol) were sequentially added to a sealed glass bottle and aged at 50 °C for 30 min. Then, 400 mL of hexane solution containing isoprene (1.26 mol) was added, and the reaction was continued at 50 °C for 360 min. Subsequently, 8-methylene-9-decen-1-ol (1.8 mmol) protected by alkylaluminum was added, and the reaction was continued at 25 °C for 240 min. Finally, the reaction was quenched dropwise with acidified ethanol. The resulting product was washed repeatedly with acidified water and ethanol, and dried under vacuum at 40 °C to obtain an isoprene-based triblock copolymer with side double bonds and polar hydroxyl groups at both ends. The obtained isoprene-based triblock copolymer was dissolved in 400 ml of tetrahydrofuran, and dicyclohexylcarbodiimide (3.6 mmol), 4-N,N-dimethylpyridine (3.6 mmol), and 4-aminophenylphosphocholine (1.8 mmol) were added sequentially. The reaction was carried out at 50 °C for 4 h. The resulting product was washed with water precipitation and dried under vacuum at 40 °C to obtain phospholipid-terminated polyisoprene. The obtained phospholipid-terminated polyisoprene was dissolved in 400 ml of toluene, and 2,2'-azobis(isobutyronitrile) (0.09 mmol) and 2-aminothiazol-5-thiol (1.8 mmol) were added to the polymer solution. The reaction was carried out at 70 °C for 4 h. Then, L-valine-N-thiocarboxylic acid anhydride (1.8 mmol) was added to the polymer solution, and the reaction was carried out at 50 °C for 4 h. The resulting product was washed with ethanol precipitation and dried under vacuum at 25 °C to obtain a biomimetic rubber with peptide and phospholipid dual-terminal functionalization.

[0131] 100 parts of biomimetic rubber, 2 parts of tetrasulfide bis(pentamethylene)thiuram, 1 part of N-tert-butyl-2-benzothiazole sulfenamide, 6 parts of zinc oxide, 1.5 parts of stearic acid, 2 parts of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 3 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll open milling method, and then vulcanized at 150℃ to obtain vulcanized biomimetic rubber.

[0132] Comparative Example 1:

[0133] Under nitrogen protection, neodymium isooctanoate (Nd(EHA)3, 0.18 mmol), diisobutylaluminum hydride (Al(i-Bu)2H, 1.8 mmol), and sesquiethylaluminum (Al2Et3Cl3, 0.18 mmol) were sequentially added to a sealed glass bottle and aged at 50 °C for 60 min. Then, 800 mL of a hexane solution containing 1.8 mol of isoprene was added, and the reaction was continued at 50 °C for 180 min. The reaction was then quenched dropwise with acidified ethanol. The resulting product was washed repeatedly with ethanol and dried under vacuum at 40 °C to obtain non-functionalized rare-earth isoprene rubber. 100 parts of rare earth isoprene rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed by two-roll milling, and then vulcanized at 150℃ to obtain vulcanized rare earth isoprene rubber.

[0134] Comparative Example 2:

[0135] 100 parts of natural rubber, 2 parts of sulfur, 2 parts of N-tert-butyl-2-benzothiazole sulfenamide, 5 parts of zinc oxide, 1 part of stearic acid, 1 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, and 2 parts of N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine were mixed using a two-roll milling method and then vulcanized at 150°C to obtain vulcanized natural rubber.

[0136] Table 1. Experimental results of vulcanized biomimetic rubbers prepared in Examples 1-7

[0137]

[0138] Table 2. Experimental results of vulcanized biomimetic rubber in Examples 8-12, vulcanized rare earth isoprene rubber in Comparative Example 1, and vulcanized natural rubber in Comparative Example 2.

[0139]

[0140] As can be seen from the above embodiments, the present invention provides a method for preparing bi-terminal functionalized biomimetic rubber, comprising the following steps: 1) preparing isoprene-based triblock copolymers with side-chain double bonds in the form of a conjugated monomer containing side-chain double bonds, isoprene, and alkylaluminum protected hydroxyl isoprene precursor under the action of a rare earth catalyst; 2) modifying the polar hydroxyl groups of the isoprene-based triblock copolymer obtained in step 1) with phospholipid compounds to obtain single-terminal phospholipid functionalized polyisoprene; 3) passing a thiol compound containing amino and / or hydroxyl groups through... The side double bonds of the single-terminal phospholipid-functionalized polyisoprene obtained in step 2) are modified by thiol-olefin click chemistry to obtain amino- and / or hydroxyl-modified phospholipid-functionalized polyisoprene; 4) The amino- and / or hydroxyl groups introduced in step 3) initiate ring-opening polymerization of N-thiocarboxylic anhydride, β-amino acid-N-thiocarboxylic anhydride, N-carboxylic anhydride or / and β-amino acid-N-carboxylic anhydride monomers, introducing a polypeptide structure into one end block of the amino- and / or hydroxyl-modified phospholipid-functionalized polyisoprene, resulting in a biomimetic rubber with both polypeptide and phospholipid end functionalization. This invention prepares a biomimetic rubber with both polypeptide and phospholipid end functionalization by simulating the fine molecular structure of natural rubber. The resulting blank vulcanized biomimetic rubber has high tensile breaking strength (27~28MPa) and high 300% elongation stress (2.1~2.2MPa). These properties are significantly better than conventional rare earth isoprene rubber and comparable to natural rubber. The biomimetic rubber prepared by this invention is expected to replace natural rubber and be used in high-end fields such as aircraft tires and high-end seals.

[0141] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a dual-end group functionalized biomimetic rubber, comprising the following steps: 1) preparing an isoprene-based tri-block copolymer with side group double bonds and polar hydroxyl groups at both ends of the block by reacting a conjugated monomer containing side group double bonds, isoprene and an alkyl aluminum protected hydroxyl isoprene precursor in the presence of a rare earth catalyst; 2) modifying the polar hydroxyl groups of the isoprene-based tri-block copolymer obtained in step 1) with a phospholipid compound to obtain a single-end phospholipid functionalized polyisoprene; 3) modifying the side group double bonds of the single-end phospholipid functionalized polyisoprene obtained in step 2) with a thiol compound containing amino or / and hydroxyl groups through thiol-ene click chemistry to obtain an amino or / and hydroxyl modified phospholipid functionalized polyisoprene; 4) introducing a polypeptide structure in the one-end block of the amino or / and hydroxyl modified phospholipid functionalized polyisoprene by initiating ring-opening polymerization of N-thio carboxylic endo anhydride, β-amino acid-N-thio carboxylic endo anhydride, N-carboxylic endo anhydride or / and β-amino acid-N-carboxylic endo anhydride monomers from the amino or / and hydroxyl groups introduced in step 3) to obtain a polypeptide and phospholipid dual-end functionalized biomimetic rubber.

2. The production method according to claim 1, characterized by, The conjugated monomer containing side group double bonds in step 1) is selected from a compound having the structure shown in formula I: Formula I; wherein R is a C1-C20 alkyl or cyclic structure; The alkyl aluminum protected hydroxyl isoprene precursor is selected from a compound having the structure shown in formula II: Formula II; wherein R is a C1-C20 alkyl or cyclic structure.

3. The production method according to claim 1, characterized by, The rare earth catalyst in step 1) comprises a rare earth compound, an organic aluminum compound and a chloride; The rare earth compound is selected from one or more of a rare earth carboxylate, a rare earth acidic phosphonate, an alkoxy rare earth, a chloride rare earth electron donor complex and a sulfonic acid rare earth electron donor complex; The organic aluminum compound is selected from a trialkyl aluminum and / or an alkyl aluminum hydride.

4. The method of claim 1, wherein, The phospholipid compound in step 2) is selected from a compound having the structure shown in formula III or formula IV: Formula III; Formula IV; R1, R2 and R3 are independently selected from a C1-C20 alkyl chain or a cyclic structure.

5. The preparation method according to claim 1, characterized in that, The thiol compound in step 3) is selected from a compound having the structure shown in formula V or formula VI: Formula V; Formula VI; R1 in formula V is selected from a C1-C20 alkyl chain or a cyclic structure; R2 in formula VI is selected from a C1-C20 alkyl chain or a cyclic structure; The N-thio carboxylic endo anhydride in step 4) has the structure shown in formula VII: Formula VII; The β-amino acid-N-thio carboxylic endo anhydride has the structure shown in formula VIII: Formula VIII, The N-carboxylic endo anhydride has the structure shown in formula IX: Formula IX; The β-amino acid-N-carboxylic endo anhydride has the structure shown in formula X: Formula X; wherein R1, R2, R3 and R4 are independently selected from a C1-C20 alkyl chain or a cyclic structure.

6. The method of claim 1, wherein, Step 1) comprises: under nitrogen protection, the conjugated monomer containing side group double bonds is aged at 20-80°C for 10-240 min in the presence of the rare earth catalyst, then isoprene solution is added, and the reaction is carried out at 20-80°C for 60-360 min, after which the alkyl aluminum protected hydroxyl isoprene precursor is added, and the reaction is carried out at 20-80°C for 60-360 min, finally acidified ethanol is added dropwise to quench the reaction; the obtained product is washed with acidified water and ethanol for multiple times, and is dried at 20-60°C under vacuum to obtain an isoprene-based tri-block copolymer with side group double bonds and polar hydroxyl groups at both ends of the block.

7. The preparation method according to claim 1, characterized in that, Step 2) comprises: The isoprene-based tri-block copolymer containing side group double bond and polar hydroxyl group obtained in step 1) is dissolved in a solvent, an activating agent of hydroxyl group and a phospholipid compound are sequentially added, and the obtained product is reacted at 0-80℃ for 2-24 hours, then precipitated and washed with water, and dried at 20-60℃ under vacuum to obtain a phospholipid functionalized polyisoprene with a single end.

8. The method of claim 1, wherein, Step 3) comprises: The phospholipid functionalized polyisoprene with a single end obtained in step 2) is dissolved in a solvent, and a free radical initiator and a thiol compound are added, and the obtained product is reacted at 20-100℃ for 0.5-4 hours to obtain a phospholipid functionalized polyisoprene modified with amino or / and hydroxyl group.

9. The method of claim 1, wherein, Step 4) comprises: N-thiocarboxylic acid anhydride, β-amino acid-N-thiocarboxylic acid anhydride, N-carboxylic acid anhydride or / and β-amino acid-N-carboxylic acid anhydride monomer is added to the polymer solution obtained in step 3), and the obtained product is reacted at 20-100℃ for 2-24 hours, then precipitated and washed with ethanol, and dried at 20-60℃ under vacuum to obtain a polypeptide and phospholipid double-end functionalized biomimetic rubber.

10. A vulcanized biomimetic rubber, comprising 100 parts by mass of the double-end functionalized biomimetic rubber prepared by the preparation method of any one of claims 1-9, 0.5-5 parts by mass of a vulcanizing agent, 0.2-5 parts by mass of a vulcanizing accelerator, 2-10 parts by mass of zinc oxide, 1-5 parts by mass of stearic acid, 0.5-5 parts by mass of an antioxidant, and 0.5-5 parts by mass of an anti-aging agent.

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