Thermoplastic acrylic resin slurry with stable reaction and rapid prototyping for in-situ pultrusion as well as preparation method and application of thermoplastic acrylic resin slurry

Abstract

The invention provides thermoplastic acrylic resin slurry for in-situ pultrusion, which is stable in reaction and rapid in molding, and the resin slurry is prepared from the following raw materials in percentage by mass: 60-80% of methyl methacrylate, 3-38% of an acrylic monomer, 0.6-8% of an auxiliary agent, 1-4% of a release agent, 0.05-5% of an initiator and 0.01-5% of a polymerization inhibitor. On the other hand, according to the embodiment of the invention, the invention further provides a preparation method of the thermoplastic acrylic resin slurry for in-situ pultrusion, which is stable in reaction and rapid in molding. According to the invention, the problem of unstable product quality of the prepared fiber-reinforced thermoplastic acrylic resin composite material caused by unstable reaction of the thermoplastic acrylic resin prepolymer slurry in a polymerization stage of an in-situ pultrusion rapid prototyping process due to unstable quality of the thermoplastic acrylic resin prepolymer slurry in the prior art is solved; according to the present invention, the raw material selection and the raw material ratio are reasonable, the compounding of the components is stable, the pre-polymerization process is simple and efficient, and the prepared composite material has characteristics of stable quality and easy promotion.

Description

Technical Field

[0001] The invention relates to the technical field of resin-based composite polymer materials, and in particular to a thermoplastic acrylic resin slurry for in-situ pultrusion molding with stable reaction and rapid molding, and a preparation method and application thereof. Background Art

[0002] Acrylic resin usually refers to a general term for a class of homopolymers and copolymers, which are polymerized from acrylic acid, methacrylic acid and their derivatives. Acrylic resin has excellent chemical properties. Its main absorption peak for light is outside the solar spectrum, and it has excellent anti-aging and optical rotation resistance. The cured polymer has excellent light transmittance, surface gloss, excellent weather resistance and good post-processing performance. Acrylic resin can be divided into thermoplastic acrylic resin and thermosetting acrylic resin according to the differences in structure and film-forming mechanism. Thermoplastic acrylic resin can be repeatedly softened by heat and solidified by cooling, that is, it can be repeatedly processed and reused. At present, thermoplastic acrylic resin is used as the basic material, and other ingredients are added to make thermoplastic acrylic resin prepolymer slurry (hereinafter referred to as thermoplastic acrylic resin slurry), and then fiber-reinforced thermoplastic acrylic resin composite materials made of glass fiber are compounded. They can be applied to photovoltaic power generation, wind power generation and other directions (such as photovoltaic frames, photovoltaic brackets, etc.), and photovoltaic power generation and wind power generation are vigorously promoted by the country as clean energy.

[0003] Most of the fiber-reinforced composite materials mentioned above are made by pultrusion rapid prototyping process, such as the reactive thermoplastic resin in-situ pultrusion process, which uses polymerized monomers or their low-viscosity prepolymers as impregnation liquid to impregnate fibers, and then initiates polymerization in the mold in the presence of an initiator to solidify the resin. For the reactive thermoplastic resin pultrusion process, the thermoplastic resin monomer or its prepolymer should meet the following requirements: stable viscosity at room temperature, fast polymerization speed at polymerization curing temperature, and good wettability with the fiber. Among them, thermoplastic acrylic resin, as a continuous fiber-reinforced reactive thermoplastic resin, can be composited with some continuous, high-strength fibers to improve the strength and stiffness of the material, and has good reaction performance; especially methyl methacrylate, which can be used to prepare prepolymers of different viscosities, and then polymerized to prepare polymers, and is a very good monomer for polymerization. However, at present, the thermoplastic acrylic resin prepolymer slurry is prone to violent reaction in a short period of time during the polymerization stage of the pultrusion rapid prototyping process, resulting in local overheating of the slurry, and then the polymerization rate is too fast and a large amount of heat is generated, that is, the polymerization reaction is not stable. If it is not controlled, this polymerization reaction is not stable. The problem will continue, expanding from the local to the whole, and the temperature will continue to rise until it is all boiling, which will eventually lead to the inability to form or poor forming, unstable product quality, such as the appearance of more bubbles, poor product morphology, low tensile strength, and easy to break. The main reason for the above problems is that the quality of the prepolymer is not easy to control. It is unstable when stored at room temperature. It will slowly polymerize over time or have a strong instantaneous polymerization phenomenon. Therefore, it is also very easy to have an unstable reaction problem during the polymerization stage of the pultrusion rapid prototyping process. In summary, how to obtain a thermoplastic acrylic resin prepolymer slurry with stable quality is the key to determining the performance of fiber-reinforced thermoplastic acrylic resin composites. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a thermoplastic acrylic resin slurry for in-situ pultrusion molding with stable reaction and rapid molding, which solves the problem in the prior art that the unstable quality of the thermoplastic acrylic resin prepolymer slurry leads to an unstable reaction in the polymerization stage of the in-situ pultrusion rapid molding process, thereby causing the unstable product quality of the prepared fiber-reinforced thermoplastic acrylic resin composite material.

[0005] According to an embodiment of the present invention, a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding is provided. The raw materials used for the resin slurry, by mass percentage, include 60-80% methyl methacrylate, 3-38% acrylic monomer, 0.6-8% additive, 1-4% release agent, 0.05-5% initiator, and 0.01-5% inhibitor.

[0006] On the other hand, according to an embodiment of the present invention, there is also provided a method for preparing a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding, which comprises the following steps:

[0007] S1, introducing an inert gas into the reaction kettle to evacuate it, then adding methyl methacrylate and acrylic monomer into the reaction kettle and stirring at a temperature of 25-70° C. and a rotation speed of 100-500 Rpm for 30-60 minutes to obtain a uniform mixture;

[0008] S2, then adding an auxiliary agent and an initiator to the uniform mixture at a temperature of 35-60° C. and under continuous stirring to carry out a prepolymerization reaction for 0.5-4 hours to obtain a prepolymer;

[0009] S3, adding a release agent and a polymerization inhibitor to the prepolymer and stirring at a rotation speed of 100-500 Rpm for 30-60 minutes, cooling to room temperature in a water bath to obtain a thermoplastic acrylic resin prepolymer slurry for in-situ injection pultrusion molding.

[0010] On the other hand, according to an embodiment of the present invention, there is also provided a continuous glass fiber reinforced thermoplastic acrylic resin composite material, which includes the above-mentioned thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding.

[0011] Finally, according to an embodiment of the present invention, there is provided an application of the continuous glass fiber reinforced thermoplastic acrylic resin composite material in the fields of photovoltaic power generation and wind power generation.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] (1) The selection of raw materials and the raw material ratio are both reasonable, and the compounding of each component is stable. The thermoplastic acrylic resin prepolymer slurry prepared by the application is relatively stable at room temperature by reasonably selecting raw materials and raw material ratios. At the same time, it reacts smoothly in the polymerization reaction of the in-situ pultrusion rapid prototyping process, and it can be quickly formed and has good wettability to glass fiber. The quality of the glass fiber reinforced thermoplastic acrylic resin composite material is relatively stable, basically free of bubbles, has good morphology, high tensile strength, and is not easy to break.

[0014] (2) The prepolymerization process is simple and efficient. It does not require high temperature or high pressure, can be quickly formed, is low cost, and is equipment-friendly. It is also beneficial for protecting the product morphology and is conducive to promotion.

[0015] (3) The glass fiber reinforced thermoplastic acrylic resin composite material prepared by the thermoplastic acrylic resin prepolymer slurry prepared in the present application and matched with the pultrusion molding process has the above advantages and can be well applied to the fields of photovoltaic power generation, wind power generation, etc.

[0016] Preferably, the acrylic monomer includes at least one of methyl acrylate, ethyl acrylate, butyl acrylate, isobutyl acrylate, lauryl acrylate, acrylic acid, methacrylic acid, vinyl methacrylate, isobutyl methacrylate, glycidyl methacrylate, allyl glycidyl ether, ethylene-acrylic acid, and maleic acid-acrylic acid.

[0017] Beneficial effects: Among them, methyl acrylate, ethyl acrylate, butyl acrylate, isobutyl acrylate, and lauryl acrylate belong to acrylic soft monomers, which can increase the toughness of the resin, give the resin better bonding properties, and have a regulating effect on the viscosity and glass transition temperature of the system; acrylic acid, methacrylic acid, vinyl methacrylate, and isobutyl methacrylate belong to acrylic hard monomers, which can improve the hardness, wear resistance, and morphological stability of the resin, and are key components for preparing high-hardness and durable polymer materials; glycidyl methacrylate, allyl glycidyl ether, ethylene-acrylic acid, and maleic acid-acrylic acid belong to acrylic functional monomers, which can provide cross-linking functional groups for the resin due to the introduction of hydroxyl and carboxyl groups, and can also serve as a bridge connecting the resin and the fiber.

[0018] Preferably, the auxiliary agent includes at least one of 1H,1H-perfluoro-n-octyl acrylate, P(MMA-co-HEMA)-g-PFPO hyperbranched polymer, butyl acetate, n-dodecyl mercaptan, and tert-dodecyl mercaptan.

[0019] Beneficial effects: These additives can enhance the hydrophobicity, anti-fouling, mechanical and heat resistance of materials, optimize the processing process, improve fluidity and stability, and their synergistic effects can broaden the application areas and meet the needs of high-performance materials in various industries.

[0020] Preferably, the release agent includes at least one of methyl silicone oil, industrial vaseline, paraffin, glycerin, fatty acid aluminum solution, zinc stearate, and stearic acid.

[0021] Beneficial effects: These release agents achieve efficient and seamless separation between the mold and the finished product, significantly reduce adhesion, and enable the finished product to be easily demolded without damaging its surface quality. At the same time, they have good lubricity and film-forming properties, reduce mold wear and extend service life. Their application can also improve production efficiency, reduce energy consumption and scrap rate, and reduce overall production costs, providing support for improving product quality, optimizing processes, and enhancing economic benefits.

[0022] Preferably, the initiator comprises at least one of dilauroyl peroxide, benzoyl peroxide, tert-butyl benzoyl peroxide, methyl ethyl ketone peroxide, tert-butyl hydroperoxide, tert-butyl peroxide isopropyl benzene, diisopropyl benzene peroxide, 2,5-dimethyl-2,5-bis(tert-butyl peroxy)hexyne-3, di-tert-amyl hydroperoxide, tert-butyl perbenzoate, tri-amyl perbenzoate, tert-butyl peroxycarbonate-2-ethylhexyl, hexadecyl peroxydicarbonate, dihexadecyl peroxydicarbonate, bis(4-tert-butylcyclohexyl) peroxydicarbonate, di-(2-ethylhexyl) peroxydicarbonate, potassium persulfate, ammonium persulfate, azobisisobutyronitrile, and azobisisoheptonitrile.

[0023] Beneficial effects: These initiators have high reactivity and selectivity, can quickly start the polymerization reaction under mild conditions, and the decomposition products have little effect on the polymerization system, which is conducive to obtaining high molecular weight, low impurity polymers. At the same time, they have good thermal and chemical stability, can maintain stable performance in complex processing environments, and ensure continuous and stable polymerization. Overall, these initiators provide a solid foundation for improving polymer quality, optimizing processes and enhancing economic benefits, and meet the needs of different fields for high-performance polymer materials.

[0024] Preferably, the polymerization inhibitor includes at least one of m-trinitrobenzene, m-dinitrobenzene, tert-butylcatechol, o-benzoquinone, p-benzoquinone, 2-tert-butylhydroquinone, 2,5-di-tert-butylhydroquinone, hydroquinone, o-methylhydroquinone, and 2,6-di-tert-butyl-4-methoxyphenol.

[0025] Beneficial effects: Adding polymerization inhibitors can effectively control and regulate the polymerization process. Inhibitors can significantly reduce the activity of the polymerization system, effectively prevent and inhibit premature and excessive polymerization, thereby ensuring the stability and quality of polymer products. At the same time, they can also improve the processing properties of polymers and the physical properties of the final products to a certain extent, such as improving heat resistance, oxidation resistance and weather resistance. In general, the introduction of polymerization inhibitors can optimize the polymerization process, improve the quality of polymers, broaden the application field, and meet the diverse needs of high-performance polymer materials in different industries. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 These are SEM comparison images of the composite materials prepared in the present invention (wherein a, b, and c correspond to Example 1, Comparative Example 1, and Comparative Example 4, respectively).

[0027] Figure 2 These are SEM comparison images of the composite materials prepared in the present invention (wherein a, d, and e correspond to Example 1, Comparative Example 9, and Comparative Example 10, respectively).

[0028] Figure 3These are SEM comparison images of the composite materials prepared in the present invention (wherein a and f correspond to Example 1 and Comparative Example 8, respectively).

[0029] Figure 4 These are SEM comparison images of the composite materials prepared in the present invention (wherein g and h correspond to Example 2 and Comparative Example 5, respectively).

[0030] Figure 5 This is a SEM comparison diagram of the composite material prepared in the present invention (wherein g, m, and n correspond to Example 2, Comparative Example 6, and Comparative Example 7, respectively). DETAILED DESCRIPTION

[0031] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0032] 1. The relevant descriptions of the raw materials involved in Examples 1 to 8 and Comparative Examples 1 to 10 are as follows:

[0033] Methyl methacrylate: National Pharmaceutical, AR (Shanghai test), containing about 0.001% 2,6-di-tert-butyl-p-cresol as a polymerization inhibitor, content (GC) ≥ 99.0%;

[0034] Methacrylic acid: National Pharmaceutical Group, AR (Shanghai test), containing about 0.01% hydroquinone as an inhibitor, content (GC) ≥ 99.0%;

[0035] Isobutyl methacrylate: Maclean, AR, containing 15-20 ppm MEHQ stabilizer, 99%;

[0036] Ethyl acrylate: Aladdin, CP, with 20ppm MEHQ stabilizer, 98.0%;

[0037] Glycidyl methacrylate: Aladdin, containing 100ppm MEHQ stabilizer, ≥97%;

[0038] Butyl acetate: Aladdin, AR, 99%;

[0039] n-Dodecanethiol: Aladdin, ≥98%;

[0040] Tert-dodecyl mercaptan: Aladdin, ≥98%;

[0041] Zinc stearate: Aladdin, industrial grade, molecular weight 632.33;

[0042] Stearic acid: National Pharmaceutical Group, AR (Shanghai trial), molecular weight 284.48;

[0043] Benzoyl peroxide: Aladdin, AR, molecular weight 242.23;

[0044] Dilauroyl peroxide: Aladdin, ≥98%, molecular weight 398.62;

[0045] Hydroquinone: National Pharmaceutical Group, AR (Shanghai test), ≥99.0;

[0046] o-Methylhydroquinone: McLean, AR, 98%.

[0047] 2. The relevant descriptions of other raw materials are as follows:

[0048] 1H,1H-Perfluorooctyl acrylate: Sinopharm, 95.0% (GC), containing stabilizer MEHQ.

[0049] Example 1

[0050] A method for preparing a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding comprises the following steps:

[0051] Step 1: nitrogen was introduced into the reactor to evacuate the reactor, and then 80 g of methyl methacrylate, 5 g of methacrylic acid, and 15 g of isobutyl methacrylate were added into the reactor and stirred at 35° C. and 400 Rpm for 30 min to obtain a uniform mixture;

[0052] Step 2: Then, at a temperature of 35° C. and under continuous stirring, 0.4 g of butyl acetate, 0.4 g of n-dodecyl mercaptan, and 0.5 g of benzoyl peroxide were added to the uniform mixture for prepolymerization for 2 h to obtain a prepolymer;

[0053] Step 3: Add 4 g of zinc stearate and 0.1 g of hydroquinone to the prepolymer and stir at a rotation speed of 400 Rpm for 30 min, then cool to room temperature in a water bath to obtain a thermoplastic acrylic resin prepolymer slurry for in-situ injection pultrusion molding.

[0054] Example 2

[0055] A method for preparing a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding comprises the following steps:

[0056] Step 1: nitrogen was introduced into the reaction kettle to evacuate the reactor, and then 75 g of methyl methacrylate, 10 g of ethyl acrylate, and 15 g of glycidyl methacrylate were added into the reaction kettle and stirred at 35° C. and 400 Rpm for 30 min to obtain a uniform mixture;

[0057] Step 2: Then, at a temperature of 35° C. and under continuous stirring, 0.3 g of butyl acetate, 0.3 g of tert-dodecyl mercaptan, and 0.5 g of dilauroyl peroxide were added to the uniform mixture for prepolymerization for 1.5 h to obtain a prepolymer;

[0058] Step 3: Add 4 g of stearic acid and 0.1 g of o-methylhydroquinone to the prepolymer and stir at a rotation speed of 400 Rpm for 30 min, then cool to room temperature in a water bath to obtain a thermoplastic acrylic resin prepolymer slurry for in-situ injection pultrusion molding.

[0059] Example 3

[0060] A method for preparing a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding comprises the following steps:

[0061] Step 1: nitrogen was introduced into the reactor to evacuate the reactor, and then 63 g of methyl methacrylate, 10 g of methacrylic acid, and 27 g of isobutyl methacrylate were added into the reactor and stirred at 35° C. and 400 Rpm for 30 min to obtain a uniform mixture;

[0062] Step 2: Then, at a temperature of 35° C. and under continuous stirring, 0.4 g of butyl acetate, 0.4 g of n-dodecyl mercaptan, and 0.5 g of benzoyl peroxide were added to the uniform mixture for prepolymerization for 2 h to obtain a prepolymer;

[0063] Step 3: Add 4 g of zinc stearate and 0.1 g of hydroquinone to the prepolymer and stir at a rotation speed of 400 Rpm for 30 min, then cool to room temperature in a water bath to obtain a thermoplastic acrylic resin prepolymer slurry for in-situ injection pultrusion molding.

[0064] Example 4

[0065] A method for preparing a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding comprises the following steps:

[0066] Step 1: nitrogen was introduced into the reactor to evacuate the reactor, and then 85 g of methyl methacrylate, 4 g of methacrylic acid, and 11 g of isobutyl methacrylate were added into the reactor and stirred at 35° C. and 400 Rpm for 30 min to obtain a uniform mixture;

[0067] Step 2: Then, at a temperature of 35° C. and under continuous stirring, 0.4 g of butyl acetate, 0.4 g of n-dodecyl mercaptan, and 0.5 g of benzoyl peroxide were added to the uniform mixture for prepolymerization for 2 h to obtain a prepolymer;

[0068] Step 3: Add 4 g of zinc stearate and 0.1 g of hydroquinone to the prepolymer and stir at a rotation speed of 400 Rpm for 30 min, then cool to room temperature in a water bath to obtain a thermoplastic acrylic resin prepolymer slurry for in-situ injection pultrusion molding.

[0069] Example 5

[0070] A method for preparing a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding comprises the following steps:

[0071] Step 1: nitrogen was introduced into the reactor to evacuate the reactor, and then 81 g of methyl methacrylate, 1 g of methacrylic acid, and 2 g of isobutyl methacrylate were added into the reactor and stirred at 25° C. and 100 Rpm for 60 min to obtain a uniform mixture;

[0072] Step 2: Then, at a temperature of 45° C. and under continuous stirring, 4.2 g of butyl acetate, 4.2 g of n-dodecyl mercaptan, and 5.3 g of benzoyl peroxide were added to the uniform mixture for prepolymerization for 2 h to obtain a prepolymer;

[0073] Step 3: Add 2.6 g of zinc stearate and 5.1 g of hydroquinone to the prepolymer and stir at a rotation speed of 400 Rpm for 30 minutes, then cool to room temperature in a water bath to obtain a thermoplastic acrylic resin prepolymer slurry for in-situ injection pultrusion molding.

[0074] Example 6

[0075] A method for preparing a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding comprises the following steps:

[0076] Step 1: nitrogen was introduced into the reactor to evacuate the reactor, and then 63 g of methyl methacrylate, 20 g of methacrylic acid, and 20 g of isobutyl methacrylate were added into the reactor and stirred at 50° C. and 300 Rpm for 45 min to obtain a uniform mixture;

[0077] Step 2: Then, at a temperature of 55° C. and under continuous stirring, 0.3 g of butyl acetate, 0.3 g of n-dodecyl mercaptan, and 0.4 g of benzoyl peroxide were added to the uniform mixture for prepolymerization for 2 h to obtain a prepolymer;

[0078] Step 3: Add 1 g of zinc stearate and 0.4 g of hydroquinone to the prepolymer and stir at a rotation speed of 100 Rpm for 60 min, then cool to room temperature in a water bath to obtain a thermoplastic acrylic resin prepolymer slurry for in-situ injection pultrusion molding.

[0079] Example 7

[0080] A method for preparing a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding comprises the following steps:

[0081] Step 1: nitrogen was introduced into the reactor to evacuate the reactor, and then 69 g of methyl methacrylate, 12 g of methacrylic acid, and 12 g of isobutyl methacrylate were added into the reactor and stirred at 70° C. and 400 Rpm for 30 min to obtain a uniform mixture;

[0082] Step 2: Then, at 60° C. and under continuous stirring, 2.1 g of butyl acetate, 2.1 g of n-dodecyl mercaptan, and 2.6 g of benzoyl peroxide were added to the uniform mixture to carry out a prepolymerization reaction for 0.5 h to obtain a prepolymer;

[0083] Step 3: Add 3 g of zinc stearate and 2.6 g of hydroquinone to the prepolymer and stir at a rotation speed of 300 Rpm for 50 min, then cool to room temperature in a water bath to obtain a thermoplastic acrylic resin prepolymer slurry for in-situ injection pultrusion molding.

[0084] Example 8

[0085] A method for preparing a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding comprises the following steps:

[0086] Step 1: nitrogen was introduced into the reactor to evacuate the reactor, and then 80 g of methyl methacrylate, 10 g of methacrylic acid, and 10 g of isobutyl methacrylate were added into the reactor and stirred at 35° C. and 500 Rpm for 30 min to obtain a uniform mixture;

[0087] Step 2: Then, at a temperature of 35° C. and under continuous stirring, 0.5 g of butyl acetate, 0.5 g of n-dodecyl mercaptan, and 0.05 g of benzoyl peroxide were added to the uniform mixture for prepolymerization for 4 hours to obtain a prepolymer;

[0088] Step 3: Add 4.34 g of zinc stearate and 0.01 g of hydroquinone to the prepolymer and stir at a rotation speed of 500 Rpm for 40 minutes, then cool to room temperature in a water bath to obtain a thermoplastic acrylic resin prepolymer slurry for in-situ injection pultrusion molding.

[0089] Comparative Example 1

[0090] The difference from Example 1 is that 48 g of methyl methacrylate, 26 g of methacrylic acid and 26 g of isobutyl methacrylate are added.

[0091] Comparative Example 2

[0092] The difference from Example 1 is that 58 g of methyl methacrylate, 21 g of methacrylic acid and 21 g of isobutyl methacrylate are added.

[0093] Comparative Example 3

[0094] The difference from Example 1 is that 90 g of methyl methacrylate, 5 g of methacrylic acid and 5 g of isobutyl methacrylate are added.

[0095] Comparative Example 4

[0096] The difference from Example 1 is that 95 g of methyl methacrylate, 2.5 g of methacrylic acid and 2.5 g of isobutyl methacrylate are added.

[0097] Comparative Example 5

[0098] The difference from Example 2 is that 0.3 g of butyl acetate and 0.3 g of tert-dodecyl mercaptan are not added.

[0099] Comparative Example 6

[0100] The difference from Example 2 is that 0.001 g of o-methylhydroquinone is added.

[0101] Comparative Example 7

[0102] The difference from Example 2 is that 10 g of o-methylhydroquinone is added.

[0103] Comparative Example 8

[0104] The difference from Example 1 is that no prepolymerization reaction is performed. Specifically, after adding the corresponding raw materials in step 2, stirring is performed for 5-10 minutes.

[0105] Comparative Example 9

[0106] The difference from Example 1 is that the prepolymerization temperature is 70°C.

[0107] Comparative Example 10

[0108] The difference from Example 1 is that the prepolymerization temperature is 25°C.

[0109] Performance Test:

[0110] The thermoplastic acrylic resin prepolymer slurry prepared in Examples 1 to 8 and Comparative Examples 1 to 10 was applied to an in-situ pultrusion process to obtain a glass fiber reinforced thermoplastic acrylic resin composite material (hereinafter referred to as a composite material, composite material or plate), and then the performance of the composite material was tested.

[0111] 1. Pultrusion process:

[0112] Pultrusion is a composite material forming process that involves impregnating continuous fibers or fabrics with resin under the traction of a traction device, and curing the resin by heating the forming die to produce composite material profiles. The process can be briefly divided into three main steps: impregnation, forming, and curing / cooling, which can be specifically divided into the following steps:

[0113] 1) Yarn arrangement: The reinforcing material (such as glass fiber roving) on ​​the yarn frame is drawn out from the yarn tube and arranged neatly and evenly. In this link, the yarn arrangement system mainly includes the yarn frame, felt spreading device, winding machine or braiding machine. In order to avoid the fiber twisting during the drawing process, a rotating mandrel is usually used to draw the fiber out from the outer wall of the yarn tube.

[0114] 2) Glue injection and impregnation: The thermoplastic acrylic resin prepolymer slurry is pumped into the mold from the glue injection machine to make the neatly arranged glass fibers evenly impregnated with the prepared thermoplastic acrylic resin prepolymer slurry.

[0115] 3) Preforming: The pre-impregnated glass fiber is continuously pulled into the shape of a sheet product through a traction device, and excess resin and bubbles are discharged.

[0116] 4) Heating and curing: The mold is usually divided into three heating zones: preheating zone, gel zone and curing zone. The three temperature zones are set at 100℃, 110℃ and 120℃ respectively, and the mold is heated and cured according to the set temperature.

[0117] 5) Traction: The profile is continuously pulled out of the mold through the traction device.

[0118] 6) Cutting: Use a cutting device to perform a 150 cm cutting test.

[0119] 2. Scanning electron microscope test

[0120] The cross-sectional morphology of the composite material was tested according to GB / T 36422-2018 Determination of Micromorphology and Diameter of Chemical Fibers by Scanning Electron Microscope. The instrument model used was Phenom ProX. The scanning electron microscope image is shown in Figure 1-Figure 5 .

[0121] Figure 1 By comparing with Example 1, SEM comparison images of the composites under different methyl methacrylate addition conditions are shown; Figure 2 By comparing with Example 1, SEM comparison images of composites at different prepolymerization temperatures are shown; Figure 3 By comparing with Example 1, the SEM comparison of the composite under the prepolymerization condition is shown; Figure 4 By comparing with Example 2, the SEM comparison of the composite material with and without the addition of the additive is shown; Figure 5 By comparing with Example 2, SEM comparison pictures of the composites under different inhibitor dosage conditions are shown.

[0122] like Figure 1 and Figure 2It can be seen that when too much or too little methyl methacrylate is added, or the prepolymerization temperature is too high or too low, there will be a few obvious holes in some areas. It is speculated that when too much or too little methyl methacrylate is added, or the prepolymerization temperature is too high or too low, the overall compounding stability of the resin formula is poor, and the local resin solidifies too early or too slowly, resulting in a few bubbles in some areas.

[0123] like Figure 3 It can be seen that there are the most bubbles in the composite board without prepolymerization. This is because the resin flows too fast in the mold without prepolymerization, thus volatilizing quickly and generating bubbles quickly. The bubble generation rate is higher than the bubble discharge rate, so that the composite material has many large holes during curing.

[0124] like Figure 4 and Figure 5 It can be seen that when no additives are added, or when there are too many or too few inhibitors, the entire composite will have a few obvious holes. It can be seen that when there are no additives to optimize the processing process to improve fluidity and stability, the composite will have poor processing performance, resulting in obvious holes after curing; when there are too many inhibitors, other components are too few, the overall compounding effect of the formula is poor, and bubbles will also appear in the whole; when there are too few inhibitors, the resin system is highly active, resulting in excessive polymerization during curing, resulting in bubbles in the whole.

[0125] However, there are basically no holes in Example 1 and Example 2, which indicates that the interface bonding between the thermoplastic acrylic resin prepolymer slurry and the glass fiber is good, that is, the morphology and quality of the glass fiber reinforced thermoplastic acrylic resin composite material prepared in the present application are good. It can be inferred that the polymerization reaction of the thermoplastic acrylic resin prepolymer slurry prepared in the present application when used in the in-situ pultrusion molding process is relatively stable. In other words, the thermoplastic acrylic resin prepolymer prepared in the present application is of high quality. It can be further inferred that the formula and process of the present application are good and matched.

[0126] 3. Tensile strength test

[0127] The tensile strength test of the composite material was carried out in accordance with Part 5: Test conditions for unidirectional fiber reinforced plastic composites in ISO 527-5 Plastics - Tests for tensile properties. The test results are shown in Table 1.

[0128] Table 1 Tensile strength of composite materials under the same test conditions

[0129]

[0130]

[0131] As shown in Table 1, the tensile strength of the composite materials corresponding to Comparative Examples 1-10 did not reach 40MPa, that is, the tensile strength of the plates of Comparative Examples 1-10 was not good, easy to break, and of poor quality; and because the bubbles in the plate are the main reason for reducing the tensile strength of the plate, it is verified again that when too much or too little methyl methacrylate is added, no additive is added, too much or too little inhibitor is added, no prepolymerization, and the prepolymerization temperature is too high or too low, the plate has bubbles or more bubbles. The above problems are presumably caused by the poor overall compounding effect of the formula or the poor prepolymerization process, which leads to too high viscosity of the prepolymer or too violent reaction.

[0132] The tensile strength of the composite materials corresponding to Examples 1 to 8 all reached 40 MPa or above, and the tensile strength was good. Combined with the above, it can be seen that the morphology of the composite materials corresponding to Examples 1 to 8 was also good, with basically no bubbles, indicating that the board prepared by the slurry of the present application has few bubbles, high tensile strength, and is not easy to break, that is, the quality is good, indicating that the polymerization reaction in the pultrusion molding process is relatively stable, so it can be inferred that the thermoplastic acrylic resin prepolymer prepared in the present application is of high quality, and it can be further inferred that the formula and process of the present application are good and matched.

[0133] In addition, the molding time of the board in each embodiment of the present application is within 2-6 minutes, and the molding time is short. It can be seen that the present invention provides a thermoplastic acrylic resin prepolymer slurry with a stable reaction and rapid molding, which has the characteristics of stable reaction, less heat release, fast molding and good molding; and the stable molding in a short time is mainly due to the compounding stability of the components of the thermoplastic acrylic resin prepolymer slurry formula, and at the same time, the formula has a good matching property with the preparation process of the thermoplastic acrylic resin prepolymer slurry, and the thermoplastic acrylic resin prepolymer slurry has a good matching property with the pultrusion equipment, thereby, the prepared board has few holes, can be quickly molded and has good quality. In addition, the thermoplastic acrylic resin prepolymer slurry prepared in the present application is applicable to a wide range of glass fibers, and both continuous short fibers and continuous long fibers are applicable.

[0134] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A thermoplastic acrylic resin slurry for in-situ pultrusion molding with stable reaction and rapid molding, characterized by: The raw materials used for the resin slurry include, by weight, 60-80% of methyl methacrylate, 3-38% of acrylic monomers, 0.6-8% of additives, 1-4% of release agents, 0.05-5% of initiators, and 0.01-5% of inhibitors; the acrylic monomers do not include methyl methacrylate.

2. The thermoplastic acrylic resin slurry for in-situ pultrusion molding with stable reaction and rapid molding as claimed in claim 1, characterized in that: The acrylic monomer includes at least one of methyl acrylate, ethyl acrylate, butyl acrylate, isobutyl acrylate, lauryl acrylate, acrylic acid, methacrylic acid, vinyl methacrylate, isobutyl methacrylate, glycidyl methacrylate, allyl glycidyl ether, ethylene-acrylic acid, and maleic acid-acrylic acid.

3. The thermoplastic acrylic resin slurry for in-situ pultrusion molding with stable reaction and rapid molding as claimed in claim 1, characterized in that: The auxiliary agent includes at least one of 1H,1H-perfluoro-n-octyl acrylate, P(MMA-co-HEMA)-g-PFPO hyperbranched polymer, butyl acetate, n-dodecyl mercaptan, and tert-dodecyl mercaptan.

4. The thermoplastic acrylic resin slurry for in-situ pultrusion molding with stable reaction and rapid molding as claimed in claim 1, characterized in that: The release agent includes at least one of methyl silicone oil, industrial vaseline, paraffin, glycerin, fatty acid aluminum solution, zinc stearate, and stearic acid.

5. The thermoplastic acrylic resin slurry for in-situ pultrusion molding with stable reaction and rapid molding as claimed in claim 1, characterized in that: The initiator comprises at least one of dilauroyl peroxide, benzoyl peroxide, tert-butyl benzoyl peroxide, methyl ethyl ketone peroxide, tert-butyl hydroperoxide, tert-butyl peroxide isopropyl benzene, diisopropyl benzene peroxide, 2,5-dimethyl-2,5-bis(tert-butyl peroxy)hexyne-3, di-tert-amyl hydroperoxide, tert-butyl perbenzoate, tri-amyl perbenzoate, tert-butyl peroxycarbonate-2-ethylhexyl, hexadecyl peroxydicarbonate, dihexadecyl peroxydicarbonate, bis(4-tert-butylcyclohexyl) peroxydicarbonate, di-(2-ethylhexyl) peroxydicarbonate, potassium persulfate, ammonium persulfate, azobisisobutyronitrile, and azobisisoheptonitrile.

6. The thermoplastic acrylic resin slurry for in-situ pultrusion molding with stable reaction and rapid molding as claimed in claim 1, characterized in that: The polymerization inhibitor includes at least one of m-trinitrobenzene, m-dinitrobenzene, tert-butylcatechol, o-benzoquinone, p-benzoquinone, 2-tert-butylhydroquinone, 2,5-di-tert-butylhydroquinone, hydroquinone, o-methylhydroquinone, and 2,6-di-tert-butyl-4-methoxyphenol.

7. A method for preparing a thermoplastic acrylic resin slurry for in-situ pultrusion molding with stable reaction and rapid molding, characterized in that: The following steps are involved: S1, introducing an inert gas into the reaction kettle to evacuate it, then adding methyl methacrylate and acrylic monomer into the reaction kettle and stirring at a temperature of 25-70° C. and a rotation speed of 100-500 Rpm for 30-60 minutes to obtain a uniform mixture; S2, then adding an auxiliary agent and an initiator to the uniform mixture at a temperature of 35-60° C. and under continuous stirring to carry out a prepolymerization reaction for 0.5-4 hours to obtain a prepolymer; S3, adding a release agent and a polymerization inhibitor to the prepolymer and stirring at a rotation speed of 100-500 Rpm for 30-60 minutes, cooling to room temperature in a water bath to obtain a thermoplastic acrylic resin prepolymer slurry for in-situ injection pultrusion molding.

8. A continuous glass fiber reinforced thermoplastic acrylic resin composite material, characterized in that: It comprises a thermoplastic acrylic resin slurry for in-situ pultrusion molding with smooth reaction and rapid molding as described in any one of claims 1 to 6.

9. Application of the continuous glass fiber reinforced thermoplastic acrylic resin composite material as claimed in claim 8 in the fields of photovoltaic power generation and wind power generation.

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