TWI702235B - Toughening vitrimer and preparation method thereof - Google Patents

Abstract

The present disclosure provides a method for toughening vitrimer. The method includes following step: providing a macromolecule initiator, performing a synthesizing step and performing a cross-linking curing step. The macromolecule initiator has a structure represented by formula (I) or formula (II): Br-PnBA-Br formula (I), h-P(nBA-co-BPEA) formula (II). The synthesizing step is for synthesizing the methyl methacrylate monomer and the glycidyl methacrylate monomer with the macromolecule initiator by an atom transfer radical polymerization method to obtain a copolymer. The cross-linking curing step is for the copolymer reacting with a bifunctional crosslinking agent under the catalysis of a transesterification catalyst to obtain a toughening vitrimer. Accordingly, the toughening vitrimer of the present disclosure has greater strain than the general thermosetting resin, and can improve a brittle PMMA to a toughening PMMA.

Description

Toughened plastic thermosetting resin and preparation method thereof

The invention relates to a toughened plastic thermosetting resin and a preparation method thereof, in particular to a toughened plastic thermosetting resin introduced with polybutyl acrylate soft chains and a preparation method thereof.

Polymethyl methacrylate resin (commonly known as acrylic) is one of the thermoplastic resins that are widely used in daily life. Its advantages include plasticity and dimensional stability. However, polymethyl methacrylate resin has some disadvantages, including low chemical resistance, low heat resistance, low mechanical properties, and so on.

In order to solve the above shortcomings, a crosslinking agent is generally added to the polymethyl methacrylate resin to cure it to form a thermosetting resin to improve its chemical resistance, heat resistance and mechanical properties. However, this method will make the polymethyl methacrylate resin The ester resin loses its original plasticity.

In addition, there are also studies using dynamic covalent bonds (Dynamic covalent bonds) to be introduced into cross-linked resins to form covalent adaptable networks (CANs), which can help improve the remodeling, processing and processing of materials without losing the material structure. Recyclability. However, although dynamic covalent bonding can make the cross-linked resin exhibit excellent stress relaxation and flow, it is not The adaptability of the resin and the life of dynamic covalent bonding are limited, so that the material can no longer rely on dynamic covalent bonding for processing.

In view of this, how to improve the chemical resistance, heat resistance and mechanical properties of the polymethyl methacrylate resin while maintaining the plasticity of the polymethyl methacrylate resin itself has become the goal of the relevant industry.

One of the objectives of the present invention is to provide a method for preparing toughened plastic thermosetting resin, which uses a macromolecular initiator with polybutyl acrylate soft segment to synthesize triblock copolymers with different configurations and super branched The core-star copolymer uses crosslinking agent and transesterification catalyst to cure and crosslink the copolymer to form a toughened plastic thermosetting resin with covalent adaptation networks (CANs).

Another object of the present invention is to provide a toughened plastic thermosetting resin, which has greater strain and can increase the toughness of the material, has good chemical resistance and heat resistance, and can achieve the original plasticity at high temperatures. And repairability.

One embodiment of the present invention is to provide a method for preparing toughened plastic thermosetting resin, which includes providing a macromolecular initiator, performing a synthesis step, and performing a crosslinking curing step. Wherein, the aforementioned macromolecular initiator has a structure as shown in formula (I) or formula (II): Br-PnBA-Br formula (I), h -P(nBA- co -BPEA) formula (II), Wherein PnBA stands for polybutyl acrylate, h stands for hyperbranched, and co stands for copolymerization. The aforementioned synthesis step is to synthesize a methyl methacrylate monomer, a glycidyl methacrylate monomer and a macromolecular initiator through an atom transfer radical polymerization method to obtain a copolymer. The aforementioned cross-linking curing step is to react the copolymer with a bifunctional cross-linking agent under the catalysis of an ester exchange catalyst to obtain a toughened plastic thermosetting resin.

According to the method for preparing toughened plastic thermosetting resin according to the foregoing embodiment, the molecular weight of the copolymer may be 23,000 to 40,000.

According to the method for preparing the toughened plastic thermosetting resin according to the foregoing embodiment, the copolymer may be a triblock copolymer.

According to the preparation method of the toughened plastic thermosetting resin according to the foregoing embodiment, the triblock copolymer has a structure as shown in formula (III): ABA formula (III), wherein A is methyl methacrylate A random copolymer block polymerized by monomers and glycidyl methacrylate monomers, B is a polybutyl acrylate block.

According to the preparation method of the toughened plastic thermosetting resin according to the foregoing embodiment, the copolymer may be a star-shaped copolymer with a hyperbranched core.

According to the preparation method of the toughened plastic thermosetting resin of the foregoing embodiment, the star-shaped copolymer with a hyperbranched core may include a central unit and a plurality of arm units, and the arm units are grafted to the central unit.

According to the method for preparing toughened plastic thermosetting resin according to the foregoing embodiment, the central unit is obtained by reacting the macroinitiator represented by formula (II) with dodecyl mercaptan, and the arm unit is a Random copolymer of methyl acrylate monomer and glycidyl methacrylate monomer.

According to the preparation method of the toughened plastic thermosetting resin according to the foregoing embodiment, the bifunctional crosslinking agent may be adipic acid or diamine.

Another embodiment of the present invention is to provide a toughened plastic thermosetting resin, which is prepared by the aforementioned preparation method.

According to the toughened plastic thermosetting resin of the foregoing embodiment, the strain of the toughened plastic thermosetting resin may be 1.50% to 3.30%.

Thus, the present invention uses the atom transfer radical polymerization method to synthesize the macromolecular initiator with polybutyl acrylate, and then shrinks it with methyl methacrylate monomer and methacrylic acid through the halogen exchange and atom transfer radical polymerization method. The glyceride monomer chain is extended to synthesize triblock copolymers with different configurations and star-shaped copolymers with hyperbranched cores, and then the copolymers, crosslinkers and transesterification catalysts are prepared into covalently adapted networks The toughened plastic thermosetting resin of the present invention can improve the brittleness of the toughened plastic thermosetting resin of the present invention and achieve a toughening effect.

100‧‧‧The preparation method of toughened plastic thermosetting resin

110, 120, 130‧‧‧step

In order to make the above and other objectives, features, advantages and embodiments of the present invention more comprehensible, the description of the accompanying drawings is as follows:

Figure 1 is a flow chart showing the steps of a method for preparing a toughened plastic thermosetting resin according to an embodiment of the present invention;

Figure 2A is a diagram showing the relationship between ln(M ₀ /M) and time of Synthesis Example 1;

Figure 2B is a graph showing the relationship between molecular weight distribution and conversion rate of Synthesis Example 1;

Figure 2C is a graph showing the relationship between molecular weight and conversion rate of Synthesis Example 1;

Figure 2D shows the molecular weight distribution of Synthesis Example 1 over time;

Figure 3A is a diagram showing the relationship between ln(M ₀ /M) and time of Synthesis Example 2;

Figure 3B is a graph showing the relationship between molecular weight distribution and conversion rate of Synthesis Example 2;

Figure 3C is a graph showing the relationship between molecular weight and conversion rate of Synthesis Example 2;

The 3D diagram shows the molecular weight distribution diagram of Synthesis Example 2 over time;

Figure 4 shows the ¹ H-NMR spectrum of Comparative Example 1 and Synthesis Example 2;

Figure 5A shows the relationship between ln(M ₀ /M) and time of tBCP;

Figure 5B shows the relationship between the molecular weight distribution of tBCP and the conversion rate;

Figure 5C shows the relationship between the molecular weight of tBCP and the conversion rate;

Figure 5D shows the molecular weight distribution of tBCP over time;

Figure 6 shows the ¹ H-NMR spectrum of Synthesis Example 3 to Synthesis Example 5;

Figure 7A shows the relationship between ln(M ₀ /M) and time of hsCP;

Figure 7B shows the relationship between the molecular weight distribution of hsCP and the conversion rate;

Figure 7C shows the relationship between the molecular weight of hsCP and the conversion rate;

Figure 7D shows the distribution of hsCP molecular weight over time;

Figure 8 shows the ¹ H-NMR spectrum of Synthesis Example 6 to Synthesis Example 8;

Figure 9 shows the toughened plastic thermosetting resin before and after curing FTIR diagram;

Figure 10 shows the TGA analysis diagram of Example 1 to Example 6;

Figure 11 shows the DSC analysis chart of Example 1 to Example 3;

Figure 12 shows the DSC analysis chart of Example 4 to Example 6;

Figure 13 shows the DMA analysis diagrams of Example 1, Example 3, Example 4, and Example 6;

Figure 14 shows the SAXS diagram of Example 1 to Example 3;

Figure 15 shows the SAXS diagram of Example 4 to Example 6;

Figure 16 shows the stress and strain diagrams of Example 1 to Example 6;

Figure 17 shows the stress and strain diagrams of Comparative Example 2, Comparative Example 3, Example 3, and Example 6;

Fig. 18 shows the POM diagram of the cracks in Example 3, Example 5 and Example 6 over time;

Figure 19 is a graph showing the degree of repair of Example 3, Example 5 and Example 6 over time; and

Figures 20A and 20B are schematic diagrams showing the plasticity of the toughened plastic thermosetting resin.

The various embodiments of the present invention will be discussed in more detail below. However, this embodiment can be an application of various inventive concepts and can be implemented in various specific ranges. The specific implementation is for illustrative purposes only, and is not limited to the scope of disclosure.

<Preparation method of toughened plastic thermosetting resin>

Please refer to FIG. 1, which is a flowchart of a method 100 for preparing a toughened plastic thermosetting resin according to an embodiment of the present invention. In FIG. 1, the method 100 for preparing a toughened plastic thermosetting resin includes step 110, step 120, and step 130.

Step 110 is to provide a macromolecular initiator, which has a structure as shown in formula (I) or formula (II): Br-PnBA-Br formula (I), h- P(nBA- co- BPEA) formula (II), where PnBA represents polybutyl acrylate, h represents hyperbranched, and co represents copolymerization. In detail, the macromolecular initiators of formula (I) and formula (II) are respectively composed of ethylene dibromoisobutyrate (2f-BiB) and 2-((2-bromopropionyl) oxygen Inimer BPEA (Inimer BPEA) bifunctional initiator and a butyl acrylate monomer are synthesized by Atom transfer radical polymerization (ATRP).

Step 120 is a synthesis step in which a methyl methacrylate (MMA) and a glycidyl methacrylate (GMA) monomer and the aforementioned macromolecular initiator are passed through ATRP synthesis to obtain a copolymer, wherein the polymerization method of ATRP can realize the controllability in the polymerization reaction, can accurately control the molecular weight of the polymer and the narrow PDI, so the molecular weight of the copolymer of the present invention can be controlled from 23,000 to 23,000. Between 40,000, and the PDI value can be less than 1.3.

The copolymer of the present invention can be a triblock copolymer (triblock copolymer, hereinafter referred to as tBCP), which is obtained by copolymerizing MMA monomer and GMA monomer with the macromolecular initiator of formula (I) through ATRP, and It has a structure as shown in formula (III): ABA formula (III), where A is a random copolymer block polymerized by MMA monomer and GMA monomer, and B is a polybutyl acrylate block. Specifically, the complete expression of the triblock copolymer of the present invention is P(MMA- r- GMA) -b- PnBA- b- P(MMA- r- GMA), where r represents random distribution (random), b Represents a block.

In addition, the copolymer of the present invention may also be a hyperbranched core star copolymer (hsCP), which is composed of MMA monomers and GMA monomers and macromolecules of formula (II). The starting agent is obtained by ATRP copolymerization. In detail, the star-shaped copolymer with a hyperbranched core of the present invention includes a central unit and a plurality of arm units, and the arm units are grafted to the central unit, wherein the central unit is composed of a macromolecular initiator of formula (II) and ten It is obtained by the reaction of two-carbon alkanethiol, and the arm unit is a random copolymer of MMA monomer and GMA monomer. Specifically, the complete expression of the star-shaped copolymer with a hyperbranched core of the present invention is s[P(MMA- r- GMA) -h- P(nBA- co- BPEA)], where s represents star ), the meanings represented by r , h, and co are as described above, and will not be repeated here.

Step 130 is a crosslinking curing step, which is to react the copolymer and a bifunctional crosslinking agent under the catalysis of an ester exchange catalyst to obtain a toughened plastic thermosetting resin, wherein the bifunctional crosslinking agent of the present invention The crosslinking agent can be adipic acid or diamine. In detail, step 130 uses copolymers Glycidyl methacrylate is used as the cross-linking point, and then bifunctional cross-linking agent and transesterification catalyst are used to cure and cross-link the copolymer to form a network structure with reversible exchange linkages. The material itself has good heat resistance and mechanical properties.

<Toughened plastic thermosetting resin>

The present invention further provides a toughened plastic thermosetting resin prepared by the aforementioned preparation method, which is a toughened plastic thermosetting resin made of a copolymer with a soft segment of PnBA, which is mainly composed of PMMA and PnBA The incompatibility between the chain segments can form a nanostructure and improve the toughness of the resin. Compared with pure PMMA, the toughened plastic thermosetting resin of the present invention has a higher strain, which can be 1.50% to 3.30%. In addition, the toughened plastic thermosetting resin of the present invention also has good chemical resistance and heat resistance, and at high temperatures, the covalent bonds in the cross-linking network can undergo transesterification by dynamic covalent exchange reaction. To achieve the plasticity and repairability of the resin.

<Synthesis example> 1. Synthesis of macromolecular initiator

Synthesis Example 1 of the present invention is a macromolecular initiator of formula (I), and its synthesis method is to combine 0.5mmol of 2f-BiB, 200mmol of nBA monomer, 1.5mmol of ligand PMDETA, 0.8mmol of Cu ⁰ , 0.2 Add mmol of CuBr ₂ and anisole as the internal standard into Schlenk bottles in order, freeze and thaw the pump cycle several times, until there are no bubbles coming out of the nitrogen back pressure, put them into the 85 ℃ oil pan to react, and respectively Take samples at appropriate times. After the reaction is completed, dilute with tetrahydrofuran, remove the copper catalyst with neutral alumina, re-precipitate with ice methanol at -50°C, then collect the precipitate, and remove the remaining solvent in a vacuum oven at 40°C. The resulting product is transparent Synthesis Example 1 of Viscous Liquid. The reaction equation of Synthesis Example 1 is shown in Table 1 below.

Please refer to Figure 2A, Figure 2B, Figure 2C, and Figure 2D. Figure 2A shows the relationship between ln (M ₀ /M) and time of Synthesis Example 1, and M ₀ is the start of the monomer The amount, M is the amount of the monomer at a certain moment. Figure 2B shows the relationship between molecular weight distribution and conversion rate of Synthesis Example 1, Figure 2C shows the relationship between molecular weight and conversion rate of Synthesis Example 1, and Figure 2D shows the relationship between molecular weight of Synthesis Example 1 and time. Distribution. From the results in Figures 2A to 2D, it can be seen that the polymerization reaction of nBA polymerized at 85°C with 2f-BiB initiator can maintain stable growth, and during the synthesis process, PDI is controlled below 1.2, which can explain Synthesis Synthesis Example 1 is the macromolecular initiator represented by formula (I).

Synthesis Example 2 of the present invention is a macromolecular initiator of formula (II), which is to first use 10mmol of Inimer BPEA, 100mmol of nBA monomer, 3.3mmol of ligand bpy, 0.11mmol of CuBr ₂ and the internal standard Add the anisole to the Schlenk bottle in sequence, freeze and thaw the pump circulation method several times, add 1.1mmol CuBr until no bubbles emerge, and then freeze and thaw the pump circulation method several times, until no bubbles emerge after the nitrogen Back pressure, put it in an oil pan at 85°C for reaction, and take samples at appropriate times. After the reaction is completed, dilute with tetrahydrofuran, remove the copper catalyst with neutral alumina, re-precipitate with ice methanol at -50°C, then collect the precipitate, and remove the remaining solvent in a vacuum oven at 40°C. The resulting product is light Comparative example 1 of yellow viscous liquid is hbP (BPEA- r- nBA). Then add 0.5mmol of Comparative Example 1, 0.75mmol of benzoin dimethyl ether, 0.5mmol of dodecane mercaptan and 30mL of tetrahydrofuran into the Schlenk bottle, freeze-thaw pump circulation method several times, until no bubbles emerge After the nitrogen back pressure, and irradiate with UV lamp at room temperature for 2 hours. After the reaction is completed, use -50℃ ice methanol to reprecipitate, then collect the precipitate, and then remove the residual solvent in a 40℃ vacuum oven. The resulting product is Synthesis example 2 of light yellow viscous liquid. The reaction equation of Synthesis Example 2 is shown in Table 2 below.

Please refer to Figure 3A, Figure 3B, Figure 3C, and Figure 3D. Figure 3A shows the relationship between ln(M ₀ /M) and time of Synthesis Example 2, and Figure 3B shows the synthesis example. Figure 2 shows the relationship between the molecular weight distribution and the conversion rate. Figure 3C shows the relationship between the molecular weight of Synthesis Example 2 and the conversion rate. Figure 3D shows the molecular weight distribution of Synthesis Example 2 over time. From the results in Figure 3A to Figure 3D, it can be seen that the polymerization reaction using Inimer BPEA to polymerize nBA at 85°C can maintain stable growth, and during the synthesis process, the polymers are all distributed uniformly, which can illustrate the synthesis example synthesized 2 is the macromolecular initiator represented by formula (II).

Please refer to Figure 4, which shows the ¹ H-NMR spectra of Comparative Example 1 and Synthesis Example 2, and from the results in Figure 4, it can be seen that the terminal vinyl group (a ₁ +a ₂ ) of Comparative Example 1 and ten After the addition reaction of dicarbanethiol under UV light irradiation, the terminal vinyl signal in the obtained synthesis example 2 disappears, which can prove that the synthesis example 2 has successfully connected the long carbon chain.

2. Synthesis of copolymer

Synthesis Example 3 to Synthesis Example 5 of the present invention are triblock copolymers (tBCP), Synthesis Example 6 to Synthesis Example 8 are star copolymers with hyperbranched cores (hsCP). The synthesis method of the above copolymers is 0.02 mmol of macromolecular initiator, 7.92 mmol of MMA monomer, 1.08 mmol of GMA monomer, 0.06 mmol of ligand dNbpy, 0.02 mmol of Cu ⁰ , 0.02 mmol of CuCl ₂ and anisole as the internal standard Put it into a Schlenk bottle in sequence, freeze and thaw the pump for several cycles, until there are no bubbles coming out of the nitrogen back pressure, put it in a 80°C oil pot for reaction, and take samples at appropriate times. After the completion of the reaction, the polymer was diluted with tetrahydrofuran, and the copper catalyst was removed with neutral alumina, and then reprecipitated with ice methanol at -50°C. Then the precipitate was collected, and the remaining solvent was removed in a vacuum oven at 40°C. The product is a white solid, wherein the macromolecular initiator used in Synthesis Example 3 to Synthesis Example 5 is Synthesis Example 1, and the macromolecular initiator used in Synthesis Example 6 to Synthesis Example 8 is Synthesis Example 2.

<Identification of Triblock Copolymer>

Please refer to Figure 5A, Figure 5B, Figure 5C and Figure 5D. Figure 5A shows the relationship between ln(M ₀ /M) of tBCP and time, and Figure 5B shows the molecular weight distribution of tBCP. Figure 5C shows the relationship between the molecular weight of tBCP and the conversion rate. Figure 5D shows the molecular weight distribution of tBCP over time. From the results in Figures 5A to 5D, it can be seen that the polymerization reaction of using the macromolecular initiator of Synthesis Example 1 to polymerize MMA and GMA at 80°C can maintain stable growth, and during the synthesis process, the PDI is controlled at 1.3 From left to right, it can be explained that the synthesized synthesis example 3 to synthesis example 5 are tBCP.

Please refer to Figure 6, which shows the ¹ H-NMR spectra of Synthesis Example 3 to Synthesis Example 5. The above ¹ H-NMR spectra are all analyzed in CDCl ₃ solution, and a, b and c respectively represent The characteristic peaks of GMA monomer, MMA monomer and nBA monomer. From the results in Figure 6, the output ratio of Synthesis Example 3 to Synthesis Example 5 can be determined, and the molecular weight and PDI value can be confirmed by GPC analysis, and the monomer conversion rate can be measured by GC. The feed rate of Synthesis Example 3 to Synthesis Example 5 The ratio, output ratio, conversion rate, molecular weight and PDI value are shown in Table 3 below.

<Identification of Star Copolymer with Hyperbranched Core>

Please refer to Figure 7A, Figure 7B, Figure 7C and Figure 7D. Figure 7A shows the relationship between hsCP ln(M ₀ /M) and time, and Figure 7B shows the molecular weight distribution of hsCP. Figure 7C shows the relationship between the molecular weight of hsCP and the conversion rate, and Figure 7D shows the molecular weight distribution of hsCP over time. From the results in Figure 7A to Figure 7D, it can be seen that the polymerization reaction of using the macromolecular initiator of Synthesis Example 2 to polymerize MMA and GMA at 80°C can maintain stable growth, and during the synthesis process, the PDI is controlled at 1.5 Hereinafter, it can be explained that the synthesized synthesis example 6 to synthesis example 8 are hsCP.

Please refer to Fig. 8, which shows the ¹ H-NMR spectra of Synthesis Example 6 to Synthesis Example 8. The above ¹ H-NMR spectra are all analyzed in CDCl ₃ solution, and a, b, and c respectively represent The characteristic peaks of GMA monomer, MMA monomer and nBA monomer. From the results in Figure 8, the output ratio of Synthesis Example 6 to Synthesis Example 8 can be determined, and its molecular weight and PDI value can be confirmed by GPC analysis, and its monomer conversion rate can be measured by GC. The progress of Synthesis Example 6 to Synthesis Example 8 The feed ratio, output ratio, conversion rate, molecular weight and PDI value are shown in Table 4 below.

<Example>

Examples 1 to 6 of the present invention are based on the toughened plastic thermosetting resins prepared in Synthesis Example 3 to Synthesis Example 8, respectively. The preparation method is that 1 g of Synthesis Example 3 is identified by ¹ H-NMR. To how much PGMA molar ratio is contained in Synthesis Example 8, then weigh 1g of Synthesis Example 3 to Synthesis Example 8, half of the PGMA molar ratio of adipic acid crosslinking agent and 5% PGMA molar ratio Zn(acac) ₂ transesterification catalyst was added to the sample bottle and dissolved in tetrahydrofuran (THF) to prepare a solution with a solid content of 25%. After that, it was evenly coated on Teflon paper and placed at room temperature for 24 hours, and then heated at 80°C, 100°C, and 120°C for 30 minutes to preheat, and then heated in a vacuum oven at 150°C and 180°C for 60 minutes. The solidification will be completed within minutes, and then take it out after cooling.

<Identification of Toughened Plasticity Thermosetting Resin>

Please refer to Figure 9, which shows the FTIR diagram of the toughened plastic thermosetting resin before and after curing. It can be seen from the results in Figure 9 that the characteristic peak of the epoxy group is located at 908 cm ^-1 . After the curing reaction, the peak of the characteristic peak of the epoxy group gradually disappears, indicating that the toughened plastic thermosetting resin has been completely cured. The toughened plastic thermosetting resin of the present invention can be divided into two types, namely the toughened plastic thermosetting resin prepared by tBCP (hereinafter referred to as tBCP-V) and the toughened plastic thermosetting resin prepared by hsCP (hereinafter referred to as tBCP-V) Referred to as hsCP-V).

<Thermal Stability Analysis>

Please refer to Figure 10, which shows the TGA analysis diagrams of Examples 1 to 6. The measurement results of the thermal cracking temperature (Td) and Char yield of Examples 1 to 6 are shown in the following table Shown in five.

From the above results, it can be seen that after tBCP-V and hsCP-V are measured by a thermogravimetric analyzer (TGA), it can be observed that the temperature of 5% of the thermal cracking of the resin is around 290°C to 310°C, indicating the toughening plasticity after modification Thermosetting resins still maintain good thermal stability.

<Analysis of Thermal Properties>

Please refer to Figures 11 and 12. Figure 11 shows the DSC analysis chart of Example 1 to Example 3, and Figure 12 shows the DSC analysis chart of Example 4 to Example 6. The measurement results of the glass transition temperature (Tg) of Example 1 to Example 6 are shown in Table 6 below.

From the above results, it can be seen that after the differential scanning measurement (DSC) measurement, when the PGMA composition in the chain segment increases, the increase in crosslinking density hinders the movement of the molecular chain, and the Tg of the resin increases with the increase in the PGMA composition. In addition, comparing tBCP-V and hsCP-V in the case of similar PGMA composition ratios, due to the geometric configuration of the hsCP-V hyperbranching, the three-dimensional obstacles in the network are relatively large, and the polymer chains are not easy to entangle, and when entering the glass transition zone When the molecular chain moves more easily than linear tBCP-V, the Tg of hsCP-V will be lower than tBCP-V.

In addition, samples of tBCP-V and hsCP-V (L=15mm, W=5mm) composed of different PGMAs were used to measure dynamic mechanical thermal analysis (DMA). Please refer to Figure 13, which shows the DMA analysis diagrams of Example 1, Example 3, Example 4 and Example 6. From the results of Figure 13, it can be seen that tBCP-V and hsCP-V composed of different PGMA As the cross-linking density increases, the movement of molecular chains is hindered, and the storage modulus in the rubber state will increase with the increase of the composition of PGMA. Then under the same PGMA composition, due to the hyperbranched geometric configuration of hsCP-V, the three-dimensional hindrance in the network is greater, the polymer chain is not easy to entangle, and the molecular chain movement is easier than linear tBCP-V, making hsCP- The storage modulus of V in the rubber state (13.1MPa) will be lower than that of tBCP-V (40.6MPa).

<Microstructure Analysis>

In order to understand the influence of the introduction of soft segments into the toughened plastic thermosetting resin, a small angle X-ray scatterometer (SAXS) was used to explore The internal microstructure of toughened plastic thermosetting resin after quality. Please refer to FIG. 14 and FIG. 15. FIG. 14 is a SAXS diagram of Embodiment 1 to Embodiment 3, and FIG. 15 is a SAXS diagram of Embodiment 4 to Embodiment 6.

From the results in Figure 14 and Figure 15, it can be seen that tBCP-V with different PGMA ratios has a similar composition of PnBA (14-20mol%). During the cross-linking process, due to the difference between the PMMA segment and the PnBA segment Incompatibility, the PnBA segment itself is arranged by PMMA to form a microphase region, the first q signal is at 0.25nm ^-1 , and the ratio of q signal to other scattering peaks is 1:2, which is judged to be a Lamellae structure. And through the formula d = 2 π/ q , the interval between the layers is calculated to be about 25 nm. In addition, hsCP-V with a similar composition of PnBA (15-22 mol%), because its PDI is too wide, the crosslinking density between the PGMA segments is inconsistent with the crosslinking rate, resulting in the microstructure of Example 4 is not obvious, but Examples 5 and 6 can be judged to be Sphere structures, and due to the geometric configuration of the hyperbranched hsCP-V, the polymer chains are relatively dense, so that they have a smaller nanometer scale (~15nm) than tBCP-V.

<Analysis of Mechanical Properties>

Please refer to Figure 16 and Figure 17. Figure 16 shows the stress and strain diagrams of Examples 1 to 6, and Figure 17 shows Comparative Example 2, Comparative Example 3, Example 3, and Example 6. In the stress-strain diagram, Comparative Example 2 is pure PMMA, and Comparative Example 3 is a plastic thermosetting resin prepared from a random copolymer synthesized by ATRP, and its PGMA composition is 21 mol%. The measurement results of stress, strain and Young's modulus of Examples 1 to 6 are shown in Table 7 below.

It can be seen from the above results that the tBCP-V and hsCP-V samples (L=60mm, W=3mm) with different PGMA composition after tensile test, when the PGMA composition in the chain segment increases, the crosslink density of the resin can be increased , Its stress and Young's modulus increase with the increase of PGMA composition, but the increase in crosslinking density makes the toughening effect of the soft segment in the network worse and the strain decreases. However, comparing tBCP-V and hsCP-V in the case of similar PGMA composition ratio, it can be seen from the above microstructure analysis that tBCP-V deteriorates the overall resin properties due to its Lamellae microstructure morphology, so that it has Sphere microstructure. The structural morphology of hsCP-V strain is larger than that of tBCP-V, but on the whole, adding soft segments to the plastic thermosetting resin can effectively improve the brittleness of pure PMMA, and because about 20mol% is introduced into the segments For the soft segment of PnBA, it can be found that the strain will be greater than that of Comparative Example 3 before modification, showing good toughness.

<plasticity and repairability>

In order to understand the repair performance of toughened and plastic thermosetting resins of different geometric configurations, the surface of Example 3, Example 5 and Example 6 was scratched with a crack, and the crack repair was observed at 150°C under hot pressing. Time changes.

Please refer to Figure 18, Figure 19, Figure 20A, and Figure 20B. Figure 18 shows the POM diagram of the cracks in Example 3, Example 5 and Example 6 over time, and Figure 19 shows Example 3, Example 5, and Example 6 are graphs of the degree of repair over time. FIG. 20A and FIG. 20B are schematic diagrams showing the plasticity of the toughened plastic thermosetting resin. From the results in Figure 18 and Figure 19, it can be seen that under the same geometric configuration, Example 6 with high PGMA composition has a higher bond density that can be exchanged in the network, so that its repair effect is better than that of low PGMA Composition of Example 5. In addition, with a similar composition of PGMA, due to the hyperbranched geometric configuration of hsCP-V, the three-dimensional hindrance in the network is larger, the polymer chain is not easy to entangle, and the molecular chain movement is easier than linear tBCP-V, making hsCP -V has a better crack repair effect, and it can be seen from the results of Figure 20A and Figure 20B that the toughened plastic thermosetting resin of the present invention can exhibit good plasticity.

In summary, the present invention provides a toughened plastic thermosetting resin and a preparation method thereof, which use a macromolecular initiator with PnBA soft segment and PMMA and GMA monomers to synthesize triblock copolymers with different configurations And a star-shaped copolymer with a hyperbranched core, and the above-mentioned copolymers are respectively cross-linked and cured into a toughened plastic thermosetting resin. The incompatibility between the main segments of PMMA and PnBA is used to form a nanostructure and increase the toughness of the material to improve the brittleness of the plastic thermosetting resin itself, and the toughening plastic thermosetting resin after the introduction of the PnBA soft segment It still retains thermal stability, repairability and plasticity.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone familiar with the art will not depart from the essence of the present invention. Within the scope of Shenhe, various changes and modifications can be made. Therefore, the scope of protection of the present invention shall be subject to those defined by the attached patent application scope.

100‧‧‧The preparation method of toughened plastic thermosetting resin

110, 120, 130‧‧‧step

Claims (10)

A method for preparing toughened plastic thermosetting resin, comprising: A macromolecular initiator is provided, and the macromolecular initiator has a structure as shown in formula (I) or formula (II): Br-PnBA-Br formula (I), h -P(nBA- co -BPEA) formula (II), where PnBA represents polybutyl acrylate, h represents hyperbranched, and co represents copolymerization; Performing a synthesis step of synthesizing a methyl methacrylate monomer and a glycidyl methacrylate monomer and the macromolecular initiator through atom transfer radical polymerization to obtain a copolymer; and A cross-linking curing step is performed, which is to react the copolymer with a bifunctional cross-linking agent under the catalysis of an ester exchange catalyst to obtain a toughened plastic thermosetting resin. The method for preparing toughened plastic thermosetting resin as described in item 1 of the scope of patent application, wherein the molecular weight of the copolymer is 23,000 to 40,000. The method for preparing toughened plastic thermosetting resin as described in item 1 of the scope of patent application, wherein the copolymer is a triblock copolymer. The method for preparing toughened plastic thermosetting resin as described in item 3 of the scope of patent application, wherein the triblock copolymer has a structure as shown in formula (III): A-B-A formula (III), Wherein A is a random copolymer block polymerized by the methyl methacrylate monomer and the glycidyl methacrylate monomer, and B is a polybutyl acrylate block. The method for preparing toughened plastic thermosetting resin as described in item 1 of the scope of patent application, wherein the copolymer is a star-shaped copolymer with a hyperbranched core. The method for preparing a toughened plastic thermosetting resin as described in item 5 of the scope of patent application, wherein the star-shaped copolymer with a hyperbranched core comprises a central unit and a plurality of arm units, and the arm units are grafted to the center unit. The method for preparing toughened plastic thermosetting resin as described in item 6 of the scope of patent application, wherein the central unit is obtained by reacting the macroinitiator represented by the formula (II) with dodecyl mercaptan, The arm units are random copolymers of the methyl methacrylate monomer and the glycidyl methacrylate monomer. According to the method for preparing toughened plastic thermosetting resin described in item 1 of the scope of patent application, the bifunctional crosslinking agent is adipic acid or diamine. A toughened plastic thermosetting resin, which is prepared by the method for preparing toughened plastic thermosetting resin as described in any one of items 1 to 8 of the scope of patent application. The toughened plastic thermosetting resin as described in item 9 of the scope of patent application, wherein the strain of the toughened plastic thermosetting resin is 1.50% to 3.30%.

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