A hyperbranched polymer toughened epoxy resin composition and a method for preparing the same

Abstract

The application provides a hyperbranched polymer toughened epoxy resin composition and a preparation method thereof, and the hyperbranched polymer toughened epoxy resin composition is obtained by modifying an epoxy resin matrix with a hyperbranched polymer, and the hyperbranched polymer is prepared from a silane coupling agent containing amino groups and a small-molecule monomer containing epoxy groups through ring-opening reaction and ester exchange polycondensation reaction. Compared with the prior art, the hyperbranched polymer toughened epoxy resin composition has the advantages that the flexible chain segment Si-O-C chain segment in the structure of the hyperbranched polymer can reduce the rigidity of the crosslinking network of the epoxy resin, and can effectively improve the toughness of the epoxy resin; in addition, the secondary amine groups of the hyperbranched polymer can promote the curing of the epoxy system; the synthesis process of the hyperbranched polymer toughened epoxy resin composition is simple, the atom utilization rate is high, no solvent and catalyst are used, and the hyperbranched polymer toughened epoxy resin composition is convenient for large-scale popularization and production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high polymer material science, in particular to a hyperbranched polymer toughened epoxy resin composition and a preparation method thereof. BACKGROUND

[0002] Epoxy resin, phenolic resin and unsaturated polyester resin are collectively referred to as "three general-purpose thermosetting resins". The epoxy resin structure contains a large number of epoxy groups and active and polar groups such as hydroxyl groups and ether bonds, which makes it have excellent reactivity and bonding performance. The cured product of epoxy resin has good mechanical properties, low curing shrinkage and good chemical stability, and is widely used in aerospace, electronics, civil engineering and mechanical engineering fields. However, the cured product of epoxy resin has high crosslinking density, and the rigidity of the crosslinking network skeleton is large, and the relative sliding between molecular chains is difficult, which makes it show brittle and poor impact toughness, etc. It is limited in engineering application. Therefore, the toughening modification of epoxy resin has always been a hot topic in scientific and engineering research, and has important application value.

[0003] At present, the main ways to modify epoxy resin include: using rigid inorganic fillers, rubber elastomers, thermoplastic resins and other second phases for modification; using thermoplastic resins or thermotropic liquid crystal polymers to form a semi-interpenetrating network type polymer by continuously penetrating the epoxy resin network; and modifying by changing the chemical structure composition of the crosslinking network of the epoxy resin and introducing "flexible segments".

[0004] The patent with application number CN201010588845.9 in the prior art discloses a kind of nano particle modified epoxy resin, which is formed by fully mixing nano particles and polymers by different physical or chemical methods to form a composite material. However, in this method, rigid inorganic particles are introduced as the second phase, and the size of the introduced structure needs to be strictly controlled. If the size of the particles is too small, stress concentration points are easily formed, and if the size of the particles is too large, it is equivalent to a two-phase structure, and the weak interface is not conducive to the toughening modification of epoxy resin.

[0005] The patent with application number CN201610213479.6 in the prior art discloses an epoxy resin composition toughened and reinforced by an imide-containing thermotropic liquid crystal polymer. This kind of polymer contains most mesogenic rigid units and a part of flexible segments in structure, which can improve the toughness of the system and slightly improve the thermal properties when used for epoxy resin modification. However, this kind of polymer also has problems such as difficult synthesis and high cost, which limits its further application.

[0006] The patent with the application number CN201210411672.2 in the prior art discloses a method for preparing a high-toughness epoxy resin matrix by using a hot melting method, and the particle size (100-2000 mesh) of the thermoplastic powder used in the patent is strictly specified. In addition, the addition of the thermoplastic plastic will increase the viscosity of the epoxy resin system to a certain extent, and will bring problems of process complication and difficult operation process control.

[0007] Therefore, the present application is proposed. SUMMARY

[0008] The present application aims to provide a hyperbranched polymer toughened epoxy resin composition and a preparation method thereof, so as to solve the problems of complicated synthesis process, high cost, difficult operation process, large use of solvents and catalysts and unsuitability for commercial mass production of the modified epoxy resin in the prior art.

[0009] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0010] A hyperbranched polymer toughened epoxy resin composition, which is obtained by modifying an epoxy resin matrix with a hyperbranched polymer, and the hyperbranched polymer is prepared from a silane coupling agent containing amino groups and a small molecule monomer containing epoxy groups through ring-opening reaction and ester exchange polycondensation reaction.

[0011] The hyperbranched polymer toughened epoxy resin composition provided by the present application can reduce the rigidity of the crosslinked network of the epoxy resin and effectively improve the toughness of the epoxy resin due to the flexible chain segment Si-O-C segment in the structure of the hyperbranched polymer. In addition, the secondary amine groups of the hyperbranched polymer can promote the curing of the epoxy system. The synthesis process of the hyperbranched polymer toughened epoxy resin composition is simple, the atomic utilization rate is high, no solvents and catalysts are used, and the mass production is facilitated.

[0012] Further, the structural formula of the hyperbranched polymer toughened epoxy resin composition is as follows:

[0013]

[0014] Further, the hyperbranched polymer is added to the epoxy resin matrix at a mass fraction of 1-12% of the mass of the epoxy resin.

[0015] Further, the silane coupling agent containing amino groups is any one of γ-aminopropyl triethoxysilane, γ-aminopropyl trimethoxysilane, γ-aminoethyl aminopropyl triethoxysilane and γ-aminoethyl aminopropyl trimethoxysilane.

[0016] Further, the epoxy-containing small molecule monomer is any one of epichlorohydrin, epoxy propane, 1,2-epoxy butane, and epoxy phenylethane.

[0017] Further, the molar ratio of the amino-containing silane coupling agent to the epoxy-containing small molecule is 1:1-3.

[0018] Further, the epoxy resin matrix is any one of E-51 epoxy resin, E-44 epoxy resin, E-31 epoxy resin, and E-42 epoxy resin.

[0019] A preparation method of a hyperbranched polymer toughened epoxy resin composition, the preparation method of the hyperbranched polymer toughened epoxy resin composition is used to prepare any one of the hyperbranched polymer toughened epoxy resin compositions, and the preparation method of the hyperbranched polymer toughened epoxy resin composition comprises the following steps:

[0020] S1, the amino-containing silane coupling agent and the epoxy-containing small molecule monomer are weighed, the molar ratio is in the range of 1:1-3, ring-opening reaction and ester exchange polycondensation reaction are carried out under temperature rising in a nitrogen atmosphere to prepare a hyperbranched polymer;

[0021] S2, the hyperbranched polymer is added to the epoxy resin matrix at 1-12% of the mass of the epoxy resin to obtain a hyperbranched polymer toughened epoxy resin composition.

[0022] The present application provides a preparation method of a hyperbranched polymer toughened epoxy resin composition, which has abundant raw material sources, simple preparation process, does not use solvent and catalyst, and is easy to mass produce.

[0023] Further, step S1 comprises the following steps:

[0024] S11, the amino-containing silane coupling agent and the epoxy-containing small molecule monomer are weighed, the molar ratio is in the range of 1:1-3, and ring-opening reaction and ester exchange polycondensation reaction are carried out under temperature rising in a nitrogen atmosphere;

[0025] S12, after distillate is collected when the viscosity of the product increases and the color deepens, heating is stopped and the reaction is ended to obtain a hyperbranched polymer.

[0026] Further, in step S11, the method of temperature rising is as follows: first, the oil bath is raised from room temperature to 30-70 DEG C, and is kept at this temperature for 3-5 hours; then, the temperature is raised in steps to 71-90 DEG C, and is kept at this temperature for 3-5 hours; then, the temperature is slowly raised to 91-100 DEG C and is kept at this temperature for 5-30 minutes.

[0027] The method of heating in step S11 divides the heating process into three stages, so that the temperature slowly and uniformly rises in the process of the reaction, which can prevent the reaction from failing to produce gel due to too fast temperature rise.

[0028] The present application provides a hyperbranched polymer toughened epoxy resin composition and a preparation method thereof, and has the following advantages over the prior art:

[0029] 1) The hyperbranched polymer toughened epoxy resin composition is prepared from a silane coupling agent containing amino groups and a small molecule monomer containing epoxy groups through ring-opening reaction and ester exchange polycondensation reaction. The prepared hyperbranched polymer has the advantages of low viscosity, high functionality, few chain entanglements, good solubility, low surface free energy, and long flexible chain.

[0030] 2) The hyperbranched polymer toughened epoxy resin composition adds hyperbranched polymers to the epoxy resin matrix. The flexible chain segment Si-O-C segment in the structure of the hyperbranched polymer can reduce the rigidity of the crosslinked network of the epoxy resin. The hyperbranched polymer is equivalent to a soft nanoparticle, which can not only avoid the defect of easy agglomeration of solid nanoparticles, but also effectively improve the toughness of the epoxy resin. In addition, the secondary amine groups of the hyperbranched polymer can promote the curing of the epoxy system and optimize the curing process performance of the epoxy resin system.

[0031] 3) The preparation method of the hyperbranched polymer toughened epoxy resin composition has abundant raw material sources, simple preparation process, and does not use solvents and catalysts, which is easy to mass-produce. The modified epoxy resin system has the characteristics of high toughness, high strength, and low curing temperature, and can be used as a resin matrix for electronic packaging materials, integrated circuit boards, and wave-transparent composite materials in the fields of aerospace, electronics and machinery, nuclear industry, etc., and has wide application. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A synthesis principle diagram of the hyperbranched polymer toughened epoxy resin composition according to the embodiment of the present application.

[0033] Figure 2 An infrared spectrum diagram of the hyperbranched polymer toughened epoxy resin composition according to the embodiment of the present application.

[0034] Figure 3 A 1 H NM diagram of the hyperbranched polymer toughened epoxy resin composition according to the embodiment of the present application.

[0035] Figure 4A hyperbranched polymer toughened epoxy resin composition according to an embodiment of the present application 13 C NMR chart.

[0036] Figure 5 A DSC test chart of a hyperbranched polymer toughened epoxy resin composition according to an embodiment of the present application. DETAILED DESCRIPTION

[0037] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The description of "first", "second" and the like in the embodiments of the present application is only for the purpose of description and cannot be understood as indicating or implying the relative importance of the technical features indicated or implying the number of the technical features indicated. Therefore, the features with "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of a person skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist and is not within the protection scope required by the present application.

[0038] The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0039] A hyperbranched polymer toughened epoxy resin composition, which is obtained by modifying an epoxy resin matrix with a hyperbranched polymer, the hyperbranched polymer is prepared by ring-opening reaction and ester exchange polycondensation reaction of a silane coupling agent containing amino groups and a small molecule monomer containing epoxy groups, and the reaction mechanism of the hyperbranched polymer is as shown in Figure 1

[0040] The flexible chain segment Si-O-C segment in the structure of the hyperbranched polymer in the hyperbranched polymer toughened epoxy resin composition according to the present application can reduce the rigidity of the crosslinked network of the epoxy resin, and at the same time can effectively improve the toughness of the epoxy resin; in addition, the secondary amine groups of the hyperbranched polymer can promote the curing of the epoxy system; the synthesis process of the hyperbranched polymer toughened epoxy resin composition is simple, the atomic utilization rate is high, no solvent and catalyst are used, and it is convenient for large-scale production.

[0041] Specifically, the structural formula of the hyperbranched polymer toughened epoxy resin composition is:

[0042]

[0043] Specifically, the hyperbranched polymer is added to the epoxy resin matrix at 1-12% of the mass of the epoxy resin.

[0044] ​More specifically, the hyperbranched polymer is added to the epoxy resin matrix in an amount of 3-9% by mass of the epoxy resin.

[0045] More specifically, the hyperbranched polymer is added to the epoxy resin matrix in an amount of 6% by mass of the epoxy resin.

[0046] At this ratio, the impact toughness of the epoxy resin composition is the best. This is because the flexible chain segment Si-O-C in the hyperbranched polymer structure makes the hyperbranched polymer slightly soft, and when the amount of hyperbranched polymer added is too large, the strength of the epoxy resin composition will decrease, and furthermore, when the amount of hyperbranched polymer added is too large, the hyperbranched polymer will locally agglomerate in the epoxy resin matrix, causing cracks, thereby reducing the impact toughness of the epoxy resin composition; when the amount of hyperbranched polymer added is too small, the toughening effect of the hyperbranched polymer is small.

[0047] Specifically, the amino-containing silane coupling agent is any one of γ-aminopropyl triethoxysilane, γ-aminopropyl trimethoxysilane, γ-aminoethyl aminopropyl triethoxysilane and γ-aminoethyl aminopropyl trimethoxysilane.

[0048] Specifically, the small molecule monomer containing an epoxy group is any one of epoxy chloropropane, epoxy propane, 1,2-epoxy butane, and epoxy phenyl ethane.

[0049] Specifically, the molar ratio of the amino-containing silane coupling agent to the small molecule containing an epoxy group is 1:1-3.

[0050] Specifically, the epoxy resin matrix is any one of E-51 epoxy resin, E-44 epoxy resin, E-31 epoxy resin, and E-42 epoxy resin.

[0051] A preparation method of a hyperbranched polymer toughened epoxy resin composition, the preparation method of the hyperbranched polymer toughened epoxy resin composition is used to prepare any one of the hyperbranched polymer toughened epoxy resin compositions, and the preparation method of the hyperbranched polymer toughened epoxy resin composition comprises the following steps:

[0052] S1, weigh the amino-containing silane coupling agent and the small molecule monomer containing an epoxy group, so that the molar ratio is in the range of 1:1-3, and perform ring-opening reaction and ester exchange polycondensation reaction under nitrogen atmosphere to prepare a hyperbranched polymer;

[0053] S2, add the hyperbranched polymer to the epoxy resin matrix in an amount of 1-12% by mass of the epoxy resin to obtain a hyperbranched polymer toughened epoxy resin composition.

[0054] The present application provides a preparation method of a hyperbranched polymer toughened epoxy resin composition, which has the advantages of rich raw material sources, simple preparation process and easy large-scale production. The modified epoxy resin system has the characteristics of high toughness, high strength and low curing temperature, and can be used as a resin matrix of electronic packaging materials, integrated circuit boards, wave-transparent composite materials and the like in the fields of aerospace, electronics and machinery, nuclear industry and the like, and has a wide application.

[0055] Specifically, the step S1 comprises the following steps:

[0056] S11, weighing the amino-containing silane coupling agent and the small molecule monomer containing epoxy groups, so that the molar ratio is in the range of 1:1-3, and performing ring-opening reaction and ester exchange polycondensation reaction under temperature rising in a nitrogen atmosphere;

[0057] S12, after collecting the distillate when the viscosity of the product increases and the color deepens, stopping heating and ending the reaction to obtain the hyperbranched polymer.

[0058] Specifically, in the step S11, the method of temperature rising is as follows: first, the oil bath is raised from room temperature to 30-70℃, and is kept at this temperature for 3-5 hours; then, the temperature is raised to 71-90℃ in steps, and is kept at this temperature for 3-5 hours; then, the temperature is slowly raised to 91-100℃, and is kept at this temperature for 5-30 minutes.

[0059] By the method of temperature rising in the step S11, the temperature rising process is divided into three stages, so that the temperature slowly and uniformly rises in the process of reaction, which can prevent the reaction from failing due to too fast temperature rising and produce gel.

[0060] In the step S11, the weighing process is as fast as possible to reduce the hydrolysis of the coupling agent by the moisture in the environment.

[0061] The hyperbranched polymer toughened epoxy resin composition of the present application has a viscosity close to that of the epoxy resin, and can be uniformly dispersed in the resin matrix when used for epoxy system modification, without affecting the processing process of the resin; the Si-O-C chain segment contained in the structure of the hyperbranched polymer can be used as a flexible unit to reduce the problem of large rigidity of the crosslinked network of the epoxy resin; the hyperbranched polymer is equivalent to a soft nanoparticle, which can not only avoid the defect that solid nanoparticles are easy to agglomerate, but also effectively improve the toughness of the epoxy resin; and the secondary amine groups contained in the polymer structure can promote the curing of the epoxy system and optimize the curing process performance of the epoxy resin system. In addition, the hyperbranched polymer is prepared by a "one-pot method" using a silane coupling agent containing an amino group and a monomer containing an epoxy group, and has the characteristics of easy availability of raw materials and simple preparation process. The modified epoxy resin system has the characteristics of high toughness and low curing temperature, and can be applied to the fields of aerospace, marine, electronics and electrical appliances, etc., and has a wide application prospect.

[0062] Example 1

[0063] A hyperbranched polymer toughened epoxy resin composition is obtained by modifying an epoxy resin matrix with a hyperbranched polymer, wherein the hyperbranched polymer is prepared by ring-opening reaction and ester exchange polycondensation reaction of a silane coupling agent containing an amino group and a small molecule monomer containing an epoxy group.

[0064] Specifically, the hyperbranched polymer is added to the epoxy resin matrix at a mass ratio of 5% of the epoxy resin.

[0065] Specifically, the silane coupling agent containing an amino group is γ-aminopropyl trimethoxysilane.

[0066] Specifically, the small molecule monomer containing an epoxy group is epoxy chloropropane (ECH).

[0067] Specifically, the molar ratio of the silane coupling agent containing an amino group to the small molecule containing an epoxy group is 1:1.2.

[0068] Specifically, the epoxy resin matrix is E-51 epoxy resin.

[0069] The preparation method of the hyperbranched polymer toughened epoxy resin composition comprises the following steps:

[0070] S1, weigh the γ-aminopropyl trimethoxysilane and the epoxy chloropropane, so that the molar ratio is 1:1.2, and perform ring-opening reaction and ester exchange polycondensation reaction under nitrogen atmosphere to prepare the hyperbranched polymer;

[0071] S2, add 5% of the hyperbranched polymer to the E-51 epoxy resin to obtain a hyperbranched polymer toughened epoxy resin composition.

[0072] Specifically, step S1 comprises the following steps:

[0073] S11, weigh γ-aminopropyltrimethoxysilane and epichlorohydrin, so that the molar ratio is 1:1.2, and perform ring-opening reaction, ester exchange polycondensation reaction under temperature rising in a nitrogen atmosphere to obtain the hyperbranched polymer;

[0074] S12, after collecting the distillate when the viscosity of the product increases and the color deepens, stop heating and end the reaction to obtain the hyperbranched polymer.

[0075] Specifically, in step S11, the method of temperature rising is: first, raise the oil bath from room temperature to 30℃, and keep the temperature at this temperature for 5 hours; then, raise the temperature to 71℃ in steps, and react for 4 hours at this temperature; then, slowly raise the temperature to 95℃ and react for 20 minutes.

[0076] Example 2

[0077] Different from example 1, in this example,

[0078] Specifically, the hyperbranched polymer is 8% of the mass of the epoxy resin added to the epoxy resin matrix.

[0079] Specifically, the amino-containing silane coupling agent is γ-aminopropyltriethoxysilane (KH550).

[0080] Specifically, the molar ratio of the amino-containing silane coupling agent to the small molecule containing epoxy group is 1:1.

[0081] Specifically, in step S11, the method of temperature rising is: first, raise the oil bath from room temperature to 50℃, and keep the temperature at this temperature for 4 hours; then, raise the temperature to 80℃ in steps, and react for 3 hours at this temperature; then, slowly raise the temperature to 91℃ and react for 30 minutes.

[0082] In this example, in step S2,

[0083] The curing agent added in the preparation process of the hyperbranched polymer toughened epoxy resin composition is methyltetrahydrophthalic anhydride (MTHPA).

[0084] Example 3

[0085] Different from example 1, in this example,

[0086] Specifically, the hyperbranched polymer is 3% of the mass of the epoxy resin added to the epoxy resin matrix.

[0087] Specifically, the amino-containing silane coupling agent is γ-aminopropyl triethoxysilane.

[0088] Specifically, the epoxy-containing small molecule monomer is 1,2-epoxybutane.

[0089] Specifically, the molar ratio of the amino-containing silane coupling agent to the epoxy-containing small molecule is 1:1.5.

[0090] Specifically, the epoxy resin matrix is E-42 epoxy resin.

[0091] Specifically, in step S11, the method of heating is first to raise the oil bath from room temperature to 70°C, and keep the temperature at this temperature for 3 hours; then the temperature is raised to 90°C in steps, and react for 5 hours at this temperature; then the temperature is slowly raised to 100°C and react for 5 minutes.

[0092] Example 4

[0093] Different from Example 1, in this example,

[0094] Specifically, the hyperbranched polymer is 1% of the mass of the epoxy resin added to the epoxy resin matrix.

[0095] Specifically, the amino-containing silane coupling agent is γ-aminopropyl triethoxysilane.

[0096] Specifically, the epoxy-containing small molecule monomer is 1,2-epoxybutane.

[0097] Specifically, the molar ratio of the amino-containing silane coupling agent to the epoxy-containing small molecule is 1:1.

[0098] Specifically, the epoxy resin matrix is E-44 epoxy resin.

[0099] Specifically, in step S11, the method of heating is first to raise the oil bath from room temperature to 60°C, and keep the temperature at this temperature for 3 hours; then the temperature is raised to 75°C in steps, and react for 5 hours at this temperature; then the temperature is slowly raised to 94°C and react for 15 minutes.

[0100] Example 5

[0101] Different from Example 1, in this example,

[0102] Specifically, the hyperbranched polymer is 1% of the mass of the epoxy resin added to the epoxy resin matrix.

[0103] Specifically, the amino-containing silane coupling agent is γ-aminopropyl triethoxysilane.

[0104] Specifically, the small molecule monomer containing epoxy group is propylene oxide.

[0105] Specifically, the molar ratio of the silane coupling agent containing amino group to the small molecule containing epoxy group is 1:2.

[0106] Specifically, in step S11, the method for increasing temperature is: first, increase the oil bath from room temperature to 40℃, and keep the temperature for 4 hours; then, increase the temperature to 85℃ in steps, and keep the temperature for 3 hours; then, slowly increase the temperature to 98℃, and keep the temperature for 10 minutes.

[0107] Example 6

[0108] Different from example 1, in this example,

[0109] Specifically, the hyperbranched polymer is 12% of the mass of the epoxy resin added into the epoxy resin matrix.

[0110] Specifically, the silane coupling agent containing amino group is γ- aminoethyl aminopropyl triethoxysilane.

[0111] Specifically, the small molecule monomer containing epoxy group is epoxy phenyl ethane.

[0112] Specifically, the molar ratio of the silane coupling agent containing amino group to the small molecule containing epoxy group is 1:3.

[0113] Specifically, the epoxy resin matrix is E-31 epoxy resin.

[0114] Specifically, in step S11, the method for increasing temperature is: first, increase the oil bath from room temperature to 45℃, and keep the temperature for 5 hours; then, increase the temperature to 70℃ in steps, and keep the temperature for 4 hours; then, slowly increase the temperature to 92℃, and keep the temperature for 20 minutes.

[0115] Example 7

[0116] In this example, different from example 3,

[0117] Specifically, the hyperbranched polymer is 6% of the mass of the epoxy resin added into the epoxy resin matrix.

[0118] Example 8

[0119] In this example, different from example 3,

[0120] Specifically, the hyperbranched polymer is 9% of the mass of the epoxy resin added into the epoxy resin matrix.

[0121] Example 9

[0122] In this example, different from example 3 is that,

[0123] Specifically, the hyperbranched polymer is 12% of the mass of the epoxy resin added to the epoxy resin matrix.

[0124] Example 10

[0125] In this comparative example, different from example 2 is that,

[0126] Specifically, in the preparation process of the hyperbranched polymer toughened epoxy resin composition, the accelerator 2,4,6-tris(dimethylaminomethyl) phenol (DMP-30) is also added.

[0127] Comparative example 1

[0128] In this comparative example, different from example 3 is that,

[0129] Specifically, no hyperbranched polymer is added to the epoxy resin matrix, and the hyperbranched polymer is 0% of the mass of the epoxy resin added to the epoxy resin matrix.

[0130] Comparative example 2

[0131] In this comparative example, different from example 3 is that,

[0132] Specifically, the hyperbranched polymer is 15% of the mass of the epoxy resin added to the epoxy resin matrix.

[0133] Comparative example 3

[0134] In this comparative example, different from example 2 is that,

[0135] Specifically, only E-51 epoxy resin and curing agent methyl tetrahydrophthalic anhydride (MTHPA) are used in the preparation process of the epoxy resin composition.

[0136] Comparative example 4

[0137] In this comparative example, different from example 2 is that,

[0138] Specifically, only E-51 epoxy resin, curing agent methyl tetrahydrophthalic anhydride (MTHPA) and accelerator 2,4,6-tris(dimethylaminomethyl) phenol (DMP-30) are used in the preparation process of the epoxy resin composition.

[0139] Performance test

[0140] I. The reactant γ-aminopropyl triethoxysilane (KH550) of example 2 and the prepared hyperbranched polymer (ECH-KH550) of example 2 were tested by infrared spectrum, and the test results were as followsFigure 2 shown.

[0141] from Figure 2 It can be seen that at 3400cm -1 The amino group in the reactant KH-550 is a primary amine, and its absorption peak is small, while the amino group in the product ECH-KH550 is a secondary amine, and its absorption peak is obvious. -1 Nearby, the absorption peak of C-Cl bond was found in the spectrum of the product ECH-KH550. This fully proves that the reactants γ-aminopropyltriethoxysilane (KH550) and epichlorohydrin (ECH) have successfully reacted to produce a hyperbranched polymer (ECH-KH550).

[0142] 2. The reactant γ-aminopropyltriethoxysilane (KH550) of Example 2 and the hyperbranched polymer (ECH-KH550) prepared in Example 2 were tested by nuclear magnetic hydrogen spectrum. The test results are as follows: Figure 3 As shown; the reactant γ-aminopropyltriethoxysilane (KH550) of Example 2 and the hyperbranched polymer (ECH-KH550) prepared in Example 2 were subjected to NMR carbon spectrum test, and the test results are as follows Figure 4 shown.

[0143] exist Figure 3 and Figure 4 In the figures, a represents γ-aminopropyltriethoxysilane (KH550), b represents epichlorohydrin (ECH), and c represents a hyperbranched polymer (ECH-KH550).

[0144] from Figure 3 It can be seen that in γ-aminopropyltriethoxysilane (KH550), the proton peaks at 3.77, 2.63, 1.50, 1.32, 1.18 and 0.58 ppm are attributed to CH3-C H 2-O-Si(1), -C H 2-NH2(5), -C H 2-CH2-NH2(4), -N H 2(6), C H 3-CH2-O-(2) and Si-C H 2-(3); In epichlorohydrin (ECH), the proton peaks at 3.57, 3.23, 2.88 and 2.67 ppm are attributed to -C H 2-Cl(4), -C H -CH2-Cl(3)-OC H 2-CH-(2) and -OC H2-CH-(1); in hyperbranched polymer (ECH-KH550), the proton peaks at 3.78, 3.67, 2.98, 2.58, 1.55, 1.19 and 0.64 ppm are attributed to CH3-C H 2-O-Si(2), -C H 2-Cl(1), -C H 2-NH2(3, 7), -C H 2-CH2-NH2(6) and Si-C H 2-(5). The above NMR hydrogen spectrum analysis shows that the hyperbranched polymer (ECH-KH550) has been successfully synthesized.

[0145] As can be seen from Figure 4 in gamma-aminopropyl triethoxysilane (KH550), the carbon signal peaks at 57.9, 44.7, 26.9, 17.9 and 7.2 ppm are attributed to Si-O- C H2-CH3(3, 6, 9), Si-CH2-CH2- C H3-NH2(13), Si-CH2- C H2-CH3-NH2(12), Si-O-CH2- C H3(4, 7, 10) and Si- C H2-CH2-CH3-NH2(11). In epichlorohydrin (ECH), the carbon signal peaks at 51.3, 46.9 and 45.0 ppm are attributed to -O- C H-CH2-Cl(2), C H2-Cl(3) and -O- C H2-CH-CH2-Cl(1). In hyperbranched polymer (ECH-KH550), the carbon signal peaks at 58.6, 50.9, 46.4, 45.8, 42.3, 20.1, 18.4 and 7.6 ppm are attributed to Si-O- C H2-CH3(7), Si-O- C H2-CH2-(2), Si-O-CH2- C H2-Cl(1), Si-O-CH2- C H2-NH-(3), Si-CH2-CH2- C H3-NH-(6), Si-CH2- C H2-CH3-NH-(5), Si-O-CH2- C H3(8) and Si- C H2-CH2-CH3-NH-(11). The above NMR carbon spectrum analysis shows that the hyperbranched polymer (ECH-KH550) has been successfully synthesized.

[0146] III. Impact toughness test was conducted on the epoxy resin compositions prepared in Example 3, Examples 7-9 and Comparative Examples 1-2, the test method was GB / T 2567-2021, and the test results are shown in Table 1.

[0147] Table 1

[0148]

[0149] From Table 1, it can be seen that:

[0150] (1) The hyperbranched polymer was added to the epoxy resin matrix at 1-12% of the mass of the epoxy resin, which improved the impact toughness of the epoxy resin. This is because the flexible chain segment Si-O-C chain segment in the structure of the hyperbranched polymer can reduce the rigidity of the crosslinked network of the epoxy resin, which not only avoids the defect that solid nanoparticles are prone to agglomeration, but also effectively improves the toughness of the epoxy resin.

[0151] (2) When the hyperbranched polymer is added to the epoxy resin matrix at 6% of the mass of the epoxy resin, the impact toughness of the epoxy resin composition is the best. This is because the flexible chain segment Si-O-C in the structure of the hyperbranched polymer makes the hyperbranched polymer soft, and when the amount of the hyperbranched polymer is too large, the strength of the epoxy resin composition will decrease. Furthermore, when the amount of the hyperbranched polymer is too large, the hyperbranched polymer will locally agglomerate in the epoxy resin matrix, causing cracks, thereby reducing the impact toughness of the epoxy resin composition; when the amount of the hyperbranched polymer is too small, the toughening effect of the hyperbranched polymer is small.

[0152] IV. DSC test was conducted on the hyperbranched polymer toughened epoxy resin composition (E-51 / MTHPA / ECH-KH550) prepared in Example 2, the epoxy resin composition (E-51 / MTHPA) prepared in Comparative Example 3, the epoxy resin composition (E-51 / MTHPA / DMP-30) prepared in Comparative Example 4, and the hyperbranched polymer toughened epoxy resin composition (E-51 / MTHPA / ECH-KH550 / DMP-30) prepared in Example 10, the test was conducted at a heating rate of 10°C / min, and the test results are shown in Table 2 and Figure 5 .

[0153] Table 2

[0154]

[0155]

[0156] From Table 2 and Figure 5As can be seen, in the epoxy resin matrix of Example 2 and Comparative Example 3, there is no accelerator DMP-30 in the system, and the addition of the hyperbranched polymer (ECH-KH550) in Example 2 can reduce the curing temperature of the epoxy resin; in the epoxy resin matrix of Example 10 and Comparative Example 4, there is an accelerator DMP-30 in the system, and the addition of the hyperbranched polymer (ECH-KH550) in Example 10 can still reduce the curing temperature of the epoxy resin.

[0157] In summary, in the epoxy resin matrix, whether there is an accelerator DMP-30 in the system, the addition of the hyperbranched polymer can reduce the curing temperature of the epoxy resin. This is because the secondary amine groups of the hyperbranched polymer can promote the curing of the epoxy system and optimize the curing process performance of the epoxy resin system.

[0158] Although the present application has been disclosed as above, the present application is not limited to this. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and the protection scope of the present application should be subject to the scope defined by the claims.

Claims

1. A hyperbranched polymer toughened epoxy resin composition, characterized in that, The hyperbranched polymer toughened epoxy resin composition is obtained by modifying an epoxy resin matrix with a hyperbranched polymer, which is prepared by ring-opening reaction and polycondensation reaction of a silane coupling agent containing amino groups and a small molecule monomer containing epoxy groups; The hyperbranched polymer is added to the epoxy resin matrix at 1-12% of the mass of the epoxy resin; The preparation method of the hyperbranched polymer comprises the following steps: S11, weigh the silane coupling agent containing amino groups and the small molecule monomer containing epoxy groups, so that the molar ratio is in the range of 1:1-3, and perform ring-opening reaction and polycondensation reaction under nitrogen atmosphere by increasing the temperature; S12, after collecting the distillate when the viscosity of the product increases and the color deepens, stop heating and end the reaction to obtain the hyperbranched polymer, In step S11, the method of increasing the temperature is: first increase the oil bath from room temperature to 30-70℃, and keep the temperature at this temperature for 3-5 hours; then increase the temperature to 71-90℃ in steps, and react at this temperature for 3-5 hours; then slowly increase the temperature to 91-100℃ and react for 5-30 minutes.

2. The hyperbranched polymer toughened epoxy resin composition according to claim 1, characterized in that, The structural formula of the hyperbranched polymer is: 。 3. The hyperbranched polymer toughened epoxy resin composition according to claim 1, wherein The silane coupling agent containing amino groups is any one of γ-aminopropyl triethoxysilane, γ-aminopropyl trimethoxysilane, γ-aminoethyl aminopropyl triethoxysilane and γ-aminoethyl aminopropyl trimethoxysilane.

4. The hyperbranched polymer toughened epoxy resin composition according to claim 1, wherein The small molecule monomer containing epoxy groups is any one of epoxy chloropropane, epoxy propane, 1,2-epoxy butane and epoxy phenyl ethane.

5. The hyperbranched polymer toughened epoxy resin composition according to claim 1, wherein The molar ratio of the silane coupling agent containing amino groups to the small molecule containing epoxy groups is 1:1-3.

6. The hyperbranched polymer toughened epoxy resin composition according to claim 1, wherein The epoxy resin matrix is any one of E-51 epoxy resin, E-44 epoxy resin, E-31 epoxy resin and E-42 epoxy resin.

7. A method for preparing a hyperbranched polymer toughened epoxy resin composition, characterized by, The preparation method of the hyperbranched polymer toughened epoxy resin composition is used to prepare the hyperbranched polymer toughened epoxy resin composition of any one of claims 1-6, and comprises the following steps: S1, weigh the silane coupling agent containing amino groups and the small molecule monomer containing epoxy groups, so that the molar ratio is in the range of 1:1-3, and perform ring-opening reaction and polycondensation reaction under nitrogen atmosphere by increasing the temperature to prepare the hyperbranched polymer; S2, add the hyperbranched polymer to the epoxy resin matrix at 1-12% of the mass of the epoxy resin to obtain the hyperbranched polymer toughened epoxy resin composition.

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