Titanate and aminosilane composite coupling agent and preparation method thereof

Abstract

The invention relates to the field of organic-polymer synthesis, and discloses a titanate and aminosilane composite coupling agent and a preparation method thereof.The titanate, aliphatic dibasic acid and lactic acid are subjected to transesterification to generate carboxyl-containing titanate, then the carboxyl-containing titanate and monohydric alcohol are subjected to esterification reaction to generate new titanate, and the new titanate is subjected to esterification reaction to obtain the coupling agent. The inorganic filler and the glass fiber are subjected to a condensation polymerization reaction with bis-primary amine alkyl trialkoxysilane to obtain the composite coupling agent, and the composite coupling agent can be effectively linked with the glass fiber, the polyamide and the coupling agent, so that the coordinated enhancement effect of the inorganic filler and the glass fiber on the polyamide composite material is realized, and finally the mechanical property of the material can be remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the field of organic polymer synthesis, and in particular relates to a titanate and aminosilane composite coupling agent and a preparation method thereof. Background Art

[0002] A coupling agent is a compound that can change the interfacial energy of glass fiber reinforced resin-based composites and inorganic filler reinforced resin-based composites. A coupling agent is an important component of a reinforced sizing agent. It generally contains two groups with different properties. One group can bond well with the surface of the fiber or inorganic filler, and the other group can bond well with the resin base. This can not only improve its surface energy, but also enhance interfacial bonding, reduce or eliminate interfacial weaknesses, and ultimately facilitate stress transfer, so that the composite material has better mechanical properties, weather resistance, water resistance and chemical corrosion resistance.

[0003] For glass fiber reinforced polyamide resin or epoxy resin-based composite materials, silane coupling agents are usually used to treat the glass fiber surface. For example, patent CN116987264A discloses a polyaminoamide silane coupling agent and its preparation method, which utilizes the trimethylsilyl hydrolyzable group contained in the silane coupling agent molecule to effectively combine with the glass fiber after hydrolysis and condensation, and the amino active group is hydrogen-bonded with the polyamide matrix. This two-way binding action promotes the coupling and cross-linking of the glass fiber surface and the resin matrix. However, in addition to using glass fiber to reinforce resin-based composite materials, it is often necessary to introduce inorganic fillers such as kaolin, mica and silica lime to improve the mechanical properties of the composite material. For inorganic filler reinforced resin-based composite materials, organic titanate is usually used as a coupling agent. This is because the titanate coupling agent will form an organic monolayer on the surface of the inorganic filler, thereby improving the surface energy of the filler, making it have the property of being organic-friendly, which helps to improve the mechanical properties of the material.

[0004] In order to meet the stringent requirements on the mechanical properties of composite materials in actual use, the use of glass fiber and inorganic fillers to synergistically reinforce resin-based composite materials will be the future development trend. However, how to prepare a coupling agent that can make the three matrices combine well is an urgent problem to be solved. Summary of the invention

[0005] In order to solve the technical problem of how to prepare a coupling agent that can well combine three matrices of glass fiber, inorganic filler and resin-based composite material mentioned in the above background technology, the present invention provides a titanate and aminosilane composite coupling agent and a preparation method. The obtained coupling agent has reactive groups of both titanate and aminosilane coupling agents, thereby being able to obtain the beneficial properties of the two coupling agents.

[0006] The specific technical solution of the present invention is: a titanate and aminosilane composite coupling agent having a structural formula shown in Formula 1: , where n 1 =1~3,n 2 =1~2,n 3 =1~3, where n 1 =1~3,n 2 =1~2,n 3 =1~3, R 1 For-OC 3 H 7 、-OC 4 H 9 or -OC 5 H 11 One of them, R 2 -CH 3 or -C 2 H 5 , R 3 For-OC 3 H 7 、-OC 4 H 9 or -OC 5 H 11 One of them.

[0007] A method for preparing a titanate and aminosilane composite coupling agent comprises the following steps: 1) titanate A, aliphatic dibasic acid and lactic acid are subjected to ester exchange reaction to obtain carboxyl titanate, wherein the molar ratio of the three monomers of titanate A, aliphatic dibasic acid and lactic acid is 1.0:(1.1-1.3):1.2; 2) subjecting carboxyl titanate to an esterification reaction with a monohydric alcohol to obtain titanate B, wherein the molar ratio of carboxyl titanate to the monohydric alcohol monomer is 1.0:1.2; 3) The titanate B and the di-primary alkyl trialkoxy silane are subjected to a condensation polymerization reaction to obtain a titanate and aminosilane composite coupling agent, wherein the molar ratio of the titanate B monomer to the di-primary alkyl trialkoxy silane monomer is 2.1:1.0.

[0008] The invention firstly carries out ester exchange reaction of three monomers, titanate, aliphatic dibasic acid and lactic acid, to generate titanate containing carboxyl group, then carries out esterification reaction with monohydric alcohol to generate the main part of titanate coupling agent, and finally carries out polycondensation reaction with diprimary amine alkyltrialkoxysilane. The obtained coupling agent has reactive groups of titanate and aminosilane coupling agent at the same time, so that the beneficial properties of the two coupling agents can be obtained. Meanwhile, the preparation process is simple and no three wastes are generated.

[0009] Furthermore, the titanate A has a structural formula shown in Formula II:

[0010] Furthermore, the aliphatic dibasic acid has a structural formula shown in Formula III:

[0011] Furthermore, the lactic acid has the structural formula shown in Formula IV:

[0012] Furthermore, the carboxylate titanate has a structural formula shown in Formula V:

[0013] Furthermore, in step 1), the reaction temperature of the transesterification reaction is 80-85° C., the heating rate is 2-2.5° C. / min, and the reaction time is 1.0-2.0 h.

[0014] Furthermore, in step 2), the reaction temperature of the esterification reaction is 65-70° C., the heating rate is 1.5-2.0° C. / min, and the reaction time is 1.0-1.5 h.

[0015] Furthermore, the monohydric alcohol has the structural formula shown in Formula VI: CH 3 -OH or CH 3 -CH 2 -OH or CH 3 -CH 2 -CH 2 -OH Formula VI.

[0016] Furthermore, the titanate B has a structural formula shown in Formula VII:

[0017] Furthermore, the diprimary amine alkyl trialkoxysilane has the structural formula shown in Formula VIII:

[0018] Furthermore, the reaction temperature in step 3) is 85-95° C., the heating rate is 2.0-2.5° C., and the reaction time is 2.0-2.5 h.

[0019] Further, in step 3), the weight average molecular weight M of the titanate and aminosilane composite coupling agent is w It is 729 to 779.

[0020] Furthermore, the intermediate that may be generated by the esterification reaction in step 2) has the structural formula shown in Formula IX:

[0021] Furthermore, the side reaction that may be generated by the polycondensation reaction in step 3) has the structural formula shown in Formula X:

[0022] Furthermore, the transesterification reaction, esterification reaction and polycondensation reaction are all carried out under nitrogen protection.

[0023] Compared with the prior art, the beneficial effects of the present invention are: 1) The present invention firstly conducts an ester exchange reaction between three monomers, namely, titanate, aliphatic dibasic acid and lactic acid, to generate a titanate containing a carboxyl group, then conducts an esterification reaction with a monohydric alcohol to generate the main part of a titanate coupling agent, and finally conducts a condensation reaction with a diprimary amine alkyltrialkoxysilane. The obtained coupling agent has reactive groups of both titanate and aminosilane coupling agents, thereby being able to obtain the beneficial properties of the two coupling agents.

[0024] 2) Compared with conventional single-type coupling agents, the composite coupling agent can form hydrogen bonds with matrices such as polyamide and epoxy resin because of the amide group contained in the main chain. The alkoxysilyl groups distributed on the chain can also enhance their effective bonding with glass fibers through hydrolysis and condensation. At the same time, the titanate group can form an organic monolayer on the surface of the inorganic filler and change the surface energy of the filler, making it have an affinity for organic matter, thereby enhancing the connection between the glass fiber, inorganic filler and resin matrix and improving the mechanical properties of the composite material.

[0025] 3) The preparation process of the present invention is simple and does not produce any three wastes. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the embodiments.

[0027] Example 1 1) Preparation of titanate and aminosilane composite coupling agent Isopropyl titanate, malonic acid and lactic acid monomers with a molar ratio of 1.0:1.1:1.2 and concentrated sulfuric acid with a total weight of 0.5% of the three monomers were added to a three-necked flask, and the temperature was raised to 80°C at a rate of 2.0°C / min under a nitrogen atmosphere. After reacting at this temperature for 1.0h, propanol was distilled out. After cooling, carboxyl titanate was obtained.

[0028] Carboxyl titanate and methanol monomers in a molar ratio of 1.0:1.2 and concentrated sulfuric acid accounting for 0.5% of the total weight of the monomers were added into a three-necked flask, and the temperature was raised to 65°C at a rate of 1.5°C / min under a nitrogen atmosphere. After reacting at this temperature for 1.2 hours, the remaining methanol was distilled out. Titanate B was obtained after cooling to 25°C.

[0029] Titanate B monomer and diprimary alkyltrialkoxysilane monomer in a molar ratio of 2.1:1.0 and 0.5% of the total weight of the monomers as EDC (1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride) catalyst are added into a three-necked flask, and the temperature is raised to 85°C at a rate of 2.0°C / min under a nitrogen atmosphere. After reacting at this temperature for 2.0h, the upper viscous liquid is taken and cooled to obtain a titanate and aminosilane composite coupling agent.

[0030] The weight average molecular weight M of the synthesized titanate and aminosilane composite coupling agent is w The viscosity is 779, and after being diluted to 50% with ethanol, it is 7.3 Pa·s.

[0031] 2) Preparation of injection molded parts Prepare the sizing solution by mass fraction, and take 12 parts of the titanate and aminosilane composite coupling agent prepared in step 1), 32 parts of unsaturated polyester resin emulsion stearic acid PEG150 ester, 15 parts of water-based epoxy resin emulsion, 3 parts of surfactant sodium dodecylbenzene sulfonate, 5 parts of pH regulator citric acid, 3 parts of antistatic agent dodecyl dimethyl quaternary ethyl salt, and 30 parts of deionized water. Immerse the glass fiber and kaolin in the prepared sizing solution for 20 minutes, take out and dry at 105°C for 12 hours.

[0032] According to the mass fraction, 30 parts of modified glass fiber, 10 parts of modified kaolin, and 70 parts of PA6 chips with a viscosity of 2.82 dL / g were taken respectively. A twin-screw extruder with a side feeding device was used for blending and granulation at a temperature of 240°C, and an injection molding machine was used for injection molding at a pressure of 50MPa and a temperature of 235°C to obtain an injection molded part.

[0033] 3) Testing The injection molded parts prepared in step 2) were subjected to mechanical property tests of tensile strength and notched impact strength.

[0034] Comparative Example 1 The difference between this comparative example and Example 1 is that KH570 silane coupling agent is used in this comparative example, and the rest of the process is the same as that of Example 1, and the specific steps are as follows: 1) Preparation of silane coupling agent The silane coupling agent used in this comparative example is KH570.

[0035] 2) Preparation of injection molded parts Prepare the sizing solution by mass fraction, and take 12 parts of KH570 silane coupling agent, 32 parts of unsaturated polyester resin emulsion stearic acid PEG150 ester, 15 parts of water-based epoxy resin emulsion, 3 parts of surfactant sodium dodecylbenzene sulfonate, 5 parts of pH regulator citric acid, 3 parts of antistatic agent dodecyl dimethyl quaternary ethyl salt, and 30 parts of deionized water. Immerse the glass fiber and kaolin in the prepared sizing solution for 20 minutes, take it out and dry it at 105°C for 12 hours.

[0036] According to the mass fraction, 30 parts of modified glass fiber, 10 parts of modified kaolin, and 70 parts of PA6 chips with a viscosity of 2.82 dL / g were taken respectively. A twin-screw extruder with a side feeding device was used for blending and granulation at a temperature of 240°C, and an injection molding machine was used for injection molding at a pressure of 50MPa and a temperature of 235°C to obtain an injection molded part.

[0037] 3) Testing The injection molded parts prepared in step 2) were subjected to mechanical property tests of tensile strength and notched impact strength.

[0038] Table 1 Effects of different silane coupling agents on the mechanical properties of the final material From the data in Table 1, we can conclude that the mechanical properties (tensile strength, notched impact strength) of the injection molding spline synthesized by the composite coupling agent of titanate and aminosilane prepared by the present invention are better than those of the single silane coupling agent. The reason is presumed to be: since the composite coupling agent contains amide groups on the main chain, it can be hydrogen-bonded with matrices such as polyamide and epoxy resin, and the alkoxysilyl groups distributed on the chain can also enhance its effective bonding with glass fiber through hydrolysis and condensation. At the same time, the titanate group can form an organic monolayer on the surface of the inorganic filler and change the surface energy of the filler, making it have an affinity for organic matter, thereby enhancing the connection between the glass fiber, the inorganic filler and the resin matrix, and improving the mechanical properties of the composite material.

[0039] Comparative Example 2 The difference between this comparative example and Example 1 is that in step 1), the molar ratio of the addition amount of isopropyl titanate, malonic acid and lactic acid is 2.0:1.1:1.2, and the rest of the process is the same as that of Example 1. The specific steps are as follows: 1) Preparation of titanate and aminosilane composite coupling agent Isopropyl titanate, malonic acid and lactic acid monomers with a molar ratio of 2.0:1.1:1.2 and concentrated sulfuric acid with a total weight of 0.5% of the three monomers were added into a three-necked flask, and the temperature was raised to 80°C at a rate of 2.0°C / min under a nitrogen atmosphere. After reacting at this temperature for 1.0h, propanol was distilled out. After cooling, carboxyl titanate was obtained.

[0040] Carboxyl titanate and methanol monomer in a molar ratio of 1.0:1.2 and concentrated sulfuric acid accounting for 0.5% of the total weight of the monomers were added into a three-necked flask, and the temperature was raised to 65°C at a rate of 1.5°C / min under a nitrogen atmosphere. After reacting at this temperature for 1.2 hours, the remaining methanol was distilled out, and titanate B was obtained after cooling to 25°C.

[0041] Titanate B monomer and diprimary alkyltrialkoxysilane monomer in a molar ratio of 2.1:1.0 and 0.5% of the total weight of the monomers as EDC (1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride) catalyst are added into a three-necked flask, and the temperature is raised to 85°C at a rate of 2.0°C / min under a nitrogen atmosphere. After reacting at this temperature for 2.0h, the upper viscous liquid is taken and cooled to obtain a titanate and aminosilane composite coupling agent.

[0042] The weight average molecular weight M of the synthesized titanate and aminosilane composite coupling agent is w The viscosity is 716, and after being diluted to 50% with ethanol, it is 6.9 Pa·s.

[0043] 2) Preparation of injection molded parts Prepare the sizing solution by mass fraction, and take 12 parts of the titanate and aminosilane composite coupling agent prepared in step 1), 32 parts of unsaturated polyester resin emulsion stearic acid PEG150 ester, 15 parts of water-based epoxy resin emulsion, 3 parts of surfactant sodium dodecylbenzene sulfonate, 5 parts of pH regulator citric acid, 3 parts of antistatic agent dodecyl dimethyl quaternary ethyl salt, and 30 parts of deionized water. Immerse the glass fiber and kaolin in the prepared sizing solution for 20 minutes, take out and dry at 105°C for 12 hours.

[0044] According to the mass fraction, 30 parts of modified glass fiber, 10 parts of modified kaolin, and 70 parts of PA6 chips with a viscosity of 2.82 dL / g were taken respectively. A twin-screw extruder with a side feeding device was used for blending and granulation at a temperature of 240°C, and an injection molding machine was used for injection molding at a pressure of 50MPa and a temperature of 235°C to obtain an injection molded part.

[0045] 3) Testing The injection molded parts prepared in step 2) were subjected to mechanical property tests of tensile strength and notched impact strength.

[0046] Table 2 Effect of titanate A addition on the properties of the final synthesized titanate and aminosilane composite coupling agent From the data in Table 2, when the addition amount of titanate A (isopropyl titanate) is excessive, the weight average molecular weight M of the synthesized titanate and aminosilane composite coupling agent is w The viscosity of the strip decreased slightly, and the mechanical properties of the strip were poor. This is because the molecular weight of isopropyl titanate is larger than that of malonic acid and lactic acid, and the reaction activity is low. The low ratio of malonic acid to lactic acid is not conducive to the growth of molecular weight and is easy to generate by-products, thus resulting in M w A decrease will not only affect the viscosity of the coupling agent, but also its bonding ability with the glass fiber and the matrix, which will in turn affect the mechanical properties of the material.

[0047] Comparative Example 3 The difference between this comparative example and Example 1 is that the molar ratio of carboxyl titanate to methanol monomer is 1.5:1.0, and the remaining steps are the same as those in Example 1. The specific steps are as follows: 1) Preparation of titanate and aminosilane composite coupling agent Isopropyl titanate, malonic acid and lactic acid monomers with a molar ratio of 1.0:1.1:1.2 and concentrated sulfuric acid with a total weight of 0.5% of the three monomers were added to a three-necked flask, and the temperature was raised to 80°C at a rate of 2.0°C / min under a nitrogen atmosphere. After reacting at this temperature for 1.0h, propanol was distilled out. After cooling, carboxyl titanate was obtained.

[0048] Carboxyl titanate and methanol monomer in a molar ratio of 1.5:1.0 and concentrated sulfuric acid accounting for 0.5% of the total weight of the monomers were added into a three-necked flask, and the temperature was raised to 65°C at a rate of 1.5°C / min under a nitrogen atmosphere. After reacting at this temperature for 1.2 hours, the remaining methanol was distilled out, and titanate B was obtained after cooling to 25°C.

[0049] Titanate B monomer and diprimary alkyltrialkoxysilane monomer in a molar ratio of 2.1:1.0 and 0.5% of the total weight of the monomers as EDC (1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride) catalyst are added into a three-necked flask, and the temperature is raised to 85°C at a rate of 2.0°C / min under a nitrogen atmosphere. After reacting at this temperature for 2.0h, the upper viscous liquid is taken and cooled to obtain a titanate and aminosilane composite coupling agent.

[0050] The weight average molecular weight M of the synthesized titanate and aminosilane composite coupling agent is w The viscosity is 732, and after being diluted to 50% with ethanol, it is 7.0 Pa·s.

[0051] 2) Preparation of injection molded parts Prepare the sizing solution by mass fraction, and take 12 parts of the titanate and aminosilane composite coupling agent prepared in step 1), 32 parts of unsaturated polyester resin emulsion stearic acid PEG150 ester, 15 parts of water-based epoxy resin emulsion, 3 parts of surfactant sodium dodecylbenzene sulfonate, 5 parts of pH regulator citric acid, 3 parts of antistatic agent dodecyl dimethyl quaternary ethyl salt, and 30 parts of deionized water. Immerse the glass fiber and kaolin in the prepared sizing solution for 20 minutes, take out and dry at 105°C for 12 hours.

[0052] According to the mass fraction, 30 parts of modified glass fiber, 10 parts of modified kaolin, and 70 parts of PA6 chips with a viscosity of 2.82 dL / g were taken respectively. A twin-screw extruder with a side feeding device was used for blending and granulation at a temperature of 240°C, and an injection molding machine was used for injection molding at a pressure of 50MPa and a temperature of 235°C to obtain an injection molded part.

[0053] 3) Testing The injection molded parts prepared in step 2) were subjected to mechanical property tests of tensile strength and notched impact strength.

[0054] Table 3 Effect of propanol addition on the performance of the final synthesized titanate and aminosilane composite coupling agent From the data in Table 2, when the amount of monohydric alcohol (propanol) added is too small, the weight average molecular weight M of the synthesized titanate and aminosilane composite coupling agent is w The viscosity of the strip is not good. This is because when the amount of monohydric alcohol (propanol) is too small, the end group of the carboxyl titanate cannot be completely esterified, and some unesterified titanates are difficult to react with the diprimary amine alkyl trialkoxy silane monomer to undergo the required polycondensation reaction. Excessive intermediate products affect the M of the product. w This will not only affect the viscosity of the coupling agent, but also its bonding ability with the glass fiber and the matrix, which will in turn affect the mechanical properties of the material.

[0055] Comparative Example 4 The difference between this comparative example and Example 1 is that in step 1), the molar ratio of the titanate B monomer to the diprimary amine alkyltrialkoxysilane monomer is 1.0:1.0, and the rest of the process is the same as that of Example 1: 1) Preparation of titanate and aminosilane composite coupling agent Isopropyl titanate, malonic acid and lactic acid monomers with a molar ratio of 1.0:1.1:1.2 and concentrated sulfuric acid with a total weight of 0.5% of the three monomers were added to a three-necked flask, and the temperature was raised to 80°C at a rate of 2.0°C / min under a nitrogen atmosphere. After reacting at this temperature for 1.0h, propanol was distilled out. After cooling, carboxyl titanate was obtained.

[0056] Carboxyl titanate and methanol monomer in a molar ratio of 1.0:1.2 and concentrated sulfuric acid accounting for 0.5% of the total weight of the monomers were added into a three-necked flask, and the temperature was raised to 65°C at a rate of 1.5°C / min under a nitrogen atmosphere. After reacting at this temperature for 1.2 hours, the remaining methanol was distilled out, and titanate B was obtained after cooling to 25°C.

[0057] Titanate B monomer and diprimary alkyltrialkoxysilane monomer in a molar ratio of 1.0:1.0, and 0.5% of the total weight of the monomers EDC (1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride) catalyst were added into a three-necked flask, and the temperature was raised to 85°C at a rate of 2.0°C / min under a nitrogen atmosphere. After reacting at this temperature for 2.0h, the upper viscous liquid was taken and cooled to obtain a titanate and aminosilane composite coupling agent.

[0058] The weight average molecular weight M of the synthesized titanate and aminosilane composite coupling agent is w The viscosity is 729, and after being diluted to 50% with ethanol, it is 6.6 Pa·s.

[0059] 2) Preparation of injection molded parts Prepare the sizing solution by mass fraction, and take 12 parts of the titanate and aminosilane composite coupling agent prepared in step 1), 32 parts of unsaturated polyester resin emulsion stearic acid PEG150 ester, 15 parts of water-based epoxy resin emulsion, 3 parts of surfactant sodium dodecylbenzene sulfonate, 5 parts of pH regulator citric acid, 3 parts of antistatic agent dodecyl dimethyl quaternary ethyl salt, and 30 parts of deionized water. Immerse the glass fiber and kaolin in the prepared sizing solution for 20 minutes, take out and dry at 105°C for 12 hours.

[0060] According to the mass fraction, 30 parts of modified glass fiber, 10 parts of modified kaolin, and 70 parts of PA6 chips with a viscosity of 2.82 dL / g were taken respectively. A twin-screw extruder with a side feeding device was used for blending and granulation at a temperature of 240°C, and an injection molding machine was used for injection molding at a pressure of 50MPa and a temperature of 235°C to obtain an injection molded part.

[0061] 3) Testing The injection molded parts prepared in step 2) were subjected to mechanical property tests of tensile strength and notched impact strength.

[0062] Table 4 Effect of the amount of diprimary amine alkyl trialkoxysilane monomer added on the properties of the final synthesized titanate and aminosilane composite coupling agent From the data in Table 2, when the ratio of titanate B to diprimary amine alkyl trialkoxysilane monomer is too low, the weight average molecular weight M of the synthesized titanate and aminosilane composite coupling agent is w The viscosity is lower, and the mechanical properties of the spline are worse. This is because the amount of di-primary alkyl trialkoxy silane monomer is large, and it is difficult for titanate B and di-primary alkyl trialkoxy silane monomer to react in a 2:1 ratio, resulting in more by-products, which not only affects the M w , it will also affect its bonding ability with the glass fiber and the matrix, which will in turn affect the mechanical properties of the material.

[0063] Example 2 1) Preparation of titanate and aminosilane composite coupling agent Isopropyl titanate, malonic acid and lactic acid monomers with a molar ratio of 1.0:1.1:1.2 and concentrated sulfuric acid with a total weight of 0.5% of the three monomers were added to a three-necked flask, and the temperature was raised to 83°C at a rate of 2.3°C / min under a nitrogen atmosphere. After reacting at this temperature for 2.3 hours, propanol was distilled out. After cooling, carboxyl titanate was obtained.

[0064] Carboxyl titanate and methanol monomers in a molar ratio of 1.0:1.2 and concentrated sulfuric acid accounting for 0.5% of the total weight of the monomers were added into a three-necked flask, and the temperature was raised to 66°C at a rate of 1.6°C / min under a nitrogen atmosphere. After reacting at this temperature for 1.2 hours, the remaining methanol was distilled out, and titanate B was obtained after cooling to 25°C.

[0065] Titanate B monomer and diprimary alkyltrialkoxysilane monomer in a molar ratio of 2.1:1.0 and 0.5% of the total weight of the monomers as EDC (1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride) catalyst are added into a three-necked flask, and the temperature is raised to 86°C at a rate of 2.2°C / min under a nitrogen atmosphere. After reacting at this temperature for 2.0h, the upper viscous liquid is taken and cooled to obtain a titanate and aminosilane composite coupling agent.

[0066] The weight average molecular weight M of the synthesized titanate and aminosilane composite coupling agent is w The viscosity is 772, and after being diluted to 50% with ethanol, it is 7.2 Pa·s.

[0067] 2) Preparation of injection molded parts Prepare the sizing solution by mass fraction, and take 12 parts of the titanate and aminosilane composite coupling agent prepared in step 1), 32 parts of unsaturated polyester resin emulsion stearic acid PEG150 ester, 15 parts of water-based epoxy resin emulsion, 3 parts of surfactant sodium dodecylbenzene sulfonate, 5 parts of pH regulator citric acid, 3 parts of antistatic agent dodecyl dimethyl quaternary ethyl salt, and 30 parts of deionized water. Immerse the glass fiber and kaolin in the prepared sizing solution for 20 minutes, take out and dry at 105°C for 12 hours.

[0068] According to the mass fraction, 30 parts of modified glass fiber, 10 parts of modified kaolin, and 70 parts of PA6 chips with a viscosity of 2.82 dL / g were taken respectively. A twin-screw extruder with a side feeding device was used for blending and granulation at a temperature of 240°C, and an injection molding machine was used for injection molding at a pressure of 50MPa and a temperature of 235°C to obtain an injection molded part.

[0069] 3) Testing The injection molded parts prepared in step 2) were subjected to mechanical property tests of tensile strength and notched impact strength.

[0070] Example 3 1) Preparation of titanate and aminosilane composite coupling agent Isopropyl titanate, succinic acid and lactic acid monomers with a molar ratio of 1.0:1.2:1.2 and concentrated sulfuric acid with a total weight of 0.5% of the three monomers were added to a three-necked flask, and the temperature was raised to 82°C at a rate of 2.2°C / min under a nitrogen atmosphere. After reacting at this temperature for 2.2 hours, propanol was distilled out. After cooling, carboxyl titanate was obtained.

[0071] Carboxyl titanate and methanol monomer in a molar ratio of 1.0:1.2 and concentrated sulfuric acid accounting for 0.5% of the total weight of the monomers were added into a three-necked flask, and the temperature was raised to 68°C at a rate of 1.8°C / min under a nitrogen atmosphere. After reacting at this temperature for 1.3 hours, the remaining methanol was distilled out, and titanate B was obtained after cooling to 25°C.

[0072] Titanate B monomer and diprimary alkyltrialkoxysilane monomer in a molar ratio of 2.1:1.0 and 0.5% of the total weight of the monomers as EDC (1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride) catalyst are added into a three-necked flask, and the temperature is raised to 90°C at a rate of 2.3°C / min under a nitrogen atmosphere. After reacting at this temperature for 2.3 hours, the upper viscous liquid is taken and cooled to obtain a titanate and aminosilane composite coupling agent.

[0073] The weight average molecular weight M of the synthesized titanate and aminosilane composite coupling agent is w The viscosity is 770, and after being diluted to 50% with ethanol, it is 7.1 Pa·s.

[0074] 2) Preparation of injection molded parts Prepare the sizing solution by mass fraction, and take 12 parts of the titanate and aminosilane composite coupling agent prepared in step 1), 32 parts of unsaturated polyester resin emulsion stearic acid PEG150 ester, 15 parts of water-based epoxy resin emulsion, 3 parts of surfactant sodium dodecylbenzene sulfonate, 5 parts of pH regulator citric acid, 3 parts of antistatic agent dodecyl dimethyl quaternary ethyl salt, and 30 parts of deionized water. Immerse the glass fiber and kaolin in the prepared sizing solution for 20 minutes, take out and dry at 105°C for 12 hours.

[0075] According to the mass fraction, 30 parts of modified glass fiber, 10 parts of modified kaolin, and 70 parts of PA6 chips with a viscosity of 2.82 dL / g were taken respectively. A twin-screw extruder with a side feeding device was used for blending and granulation at a temperature of 240°C, and an injection molding machine was used for injection molding at a pressure of 50MPa and a temperature of 235°C to obtain an injection molded part.

[0076] 3) Testing The injection molded parts prepared in step 2) were subjected to mechanical property tests of tensile strength and notched impact strength.

[0077] The raw materials and equipment used in the present invention, unless otherwise specified, are all commonly used raw materials and equipment in the art; the methods used in the present invention, unless otherwise specified, are all conventional methods in the art.

[0078] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A titanate and aminosilane composite coupling agent, characterized in that: It has the structural formula shown in Formula 1: , Wherein, n1=1-3, n2=1-2, n3=1-3, R1 is -OC3H7, -OC4H9 or -OC5H 11 R2 is -CH3 or -C2H5, R3 is -OC3H7, R3 is -OC3H7, -OC4H9 or -OC5H 11 One of them.

2. A method for preparing the titanate and aminosilane composite coupling agent according to claim 1, characterized in that: The following steps are involved: 1) subjecting titanate A, aliphatic dibasic acid and lactic acid to transesterification to obtain carboxyl titanate; the molar ratio of titanate A, aliphatic dibasic acid and lactic acid is 1.0-1.05:(1.1-1.3):1.2-1.25; 2) subjecting carboxyl titanate to an esterification reaction with a monohydric alcohol to obtain titanate B, wherein the molar ratio of carboxyl titanate to the monohydric alcohol monomer is 1.0:1.1-1.2; 3) The titanate B and the di-primary alkyl trialkoxy silane are subjected to a condensation polymerization reaction to obtain a titanate and aminosilane composite coupling agent, wherein the molar ratio of the titanate B monomer to the di-primary alkyl trialkoxy silane monomer is 2.1-2.2:1.

0.

3. The method for preparing a titanate and aminosilane composite coupling agent according to claim 2, characterized in that: In step 1), the aliphatic dibasic acid has a structural formula shown in formula III:

4. The method for preparing a titanate and aminosilane composite coupling agent according to claim 2 or 3, characterized in that: In step 1), the reaction temperature of the transesterification reaction is 80-85° C., the heating rate is 2-2.5° C. / min, and the reaction time is 1.0-2.0 h.

5. The method for preparing a titanate and aminosilane composite coupling agent according to claim 2, characterized in that: In step 2), the monohydric alcohol has the structural formula shown in formula VI: CH3-OH or CH3-CH2-OH or CH3-CH2-CH2-OH Formula VI.

6. The method for preparing a titanate and aminosilane composite coupling agent according to claim 2 or 5, characterized in that: In step 2), the reaction temperature of the esterification reaction is 65-70° C., the heating rate is 1.5-2.0° C. / min, and the reaction time is 1.0-1.5 h.

7. The method for preparing a titanate and aminosilane composite coupling agent according to claim 2, characterized in that: In step 2), n1=1~3, n4=1~3.

8. The method for preparing a titanate and aminosilane composite coupling agent according to claim 5, characterized in that: The reaction temperature in step 3) is 85-95°C, the heating rate is 2.0-2.5°C, and the reaction time is 2.0-2.5h.

9. The method for preparing a titanate and aminosilane composite coupling agent according to claim 5, characterized in that: In step 3), the weight average molecular weight M of the titanate and aminosilane composite coupling agent is w It is 729 to 779.

10. The method for preparing a titanate and aminosilane composite coupling agent according to claim 5, characterized in that: The transesterification reaction, esterification reaction and polycondensation reaction were all carried out under nitrogen protection.

Images