Polycarbonate oligomer having an unsaturated double bond, method for preparing the same, curable composition, and method for preparing a low dielectric constant cured product.
By preparing polycarbonate oligomers with unsaturated double bonds through alcoholysis and esterification, the method addresses recycling challenges, producing high-value circuit board materials with improved electrical and thermal properties.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- SWANCOR INNOVATION & INCUBATION CO LTD
- Filing Date
- 2023-05-09
- Publication Date
- 2026-04-22
AI Technical Summary
The recycling of waste polycarbonate materials is challenging due to molecular weight reduction during physical processing, and chemical recycling methods are cumbersome and costly, limiting their application in high-value products like circuit boards, especially with the increasing demand for high-frequency and high-speed operations.
A method is developed to prepare polycarbonate oligomers with unsaturated double bonds through alcoholysis and esterification, enabling them to be copolymerized with polyphenylene ether resins, resulting in cured products with excellent electrical and thermal properties.
The method allows for the production of high-value circuit board materials from recycled polycarbonate, maintaining good electrical properties and heat resistance, aligning with environmental and regulatory requirements.
Smart Images
Figure 2026513080000001_ABST
Abstract
Description
[Technical Field]
[0001] This disclosure relates to polycarbonate oligomers having unsaturated double bonds, methods for preparing the same, curable compositions, and methods for preparing low dielectric constant cured products, and more particularly to polycarbonate oligomers having unsaturated double bonds that can be copolymerized with polyphenylene ether resins, methods for preparing the same, curable compositions, and methods for preparing low dielectric constant cured products. [Background technology]
[0002] Polycarbonate (PC) is a thermoplastic polymer material formed by the transesterification reaction of bisphenol A and diphenyl carbonate at high temperatures. Polycarbonate has excellent heat resistance and mechanical strength and is widely used in consumer goods such as eyeglass lenses, optical discs, data storage devices, and automotive light covers. [Overview of the project] [Problems that the invention aims to solve]
[0003] As the use of polycarbonate continues to increase, the challenges of polycarbonate recycling are increasingly attracting attention. Currently, in the market, the recycling of waste polycarbonate products is mainly carried out through physical processing. After separating the polycarbonate from the metal parts in the product, it is crushed, kneaded, and processed into other products through high-temperature processes. However, the crushing process reduces the molecular weight of the polycarbonate, and further deteriorates the physical properties such as the mechanical properties of the recycled product, so there are still significant limitations on its application.
[0004] Currently, many studies are attempting to process waste polycarbonate products using chemical recycling methods, most of which yield bisphenol A (BPA) monomers through decomposition, which are then used again in the synthesis of polycarbonate. However, this method requires large amounts of solvents or catalysts and complicated purification processes to obtain high-purity bisphenol A, making industrialization of this method difficult due to environmental protection and cost considerations.
[0005] In recent years, the demand for consumer electronic products has increased significantly, and the demand for circuit boards has also surged. For example, in Japan, there is a precedent for using polycarbonate as an electronic material (e.g., publication number TW 202024175A), and in the aforementioned patent, polycarbonate oligomer is used as an epoxy curing agent, and by copolymerizing the two, an epoxy resin cured product with good heat resistance and electrical properties is formed. This material has a measured dielectric constant (D). k The dielectric loss tangent (D) is 2.68. f The ratio is 0.0132, making it a promising material for printed circuit boards.
[0006] In response to the current needs for high-frequency and high-speed operation in high-end circuit boards, NORYLTM SA9000 resin, provided by SABIC, is becoming the mainstream resin. This resin is a polyphenylene ether (PPE) oligomer having difunctional unsaturated groups at its ends. It exhibits good heat resistance and rigidity after radical polymerization, and does not generate polar functional groups after curing, resulting in relatively lower dielectric loss tangent and relative permittivity compared to conventional epoxy resins.
[0007] With growing environmental awareness in various countries, the recycling and reuse of plastics is becoming increasingly important. The European Union has even issued a ban on general plastic products, imposing restrictions that mandate the use of a certain amount of recycled plastic in some plastic products. In response to this trend, the above concept is gradually spreading to various chemical products, and brand manufacturers are successively implementing proactive regulatory plans at the raw material stage. However, at present, it is difficult to prepare materials for high-end circuit board products using recycled plastics, and there are also requirements for the electrical properties of the products themselves, so radical polymerization curing systems are becoming mainstream. Based on the above, if waste polycarbonate can be modified into a short-chain unsaturated resin, it may be possible to maintain good electrical properties and heat resistance, and it can be used as one of the recycled raw materials for circuit board materials in response to future trends. [Means for solving the problem]
[0008] The object of this disclosure is to provide a method for preparing oligomers by recycling waste polycarbonate, wherein the prepared oligomers exhibit excellent copolymerization properties with polyphenylene ether materials currently widely used in the market for high-frequency circuit boards, and possess excellent heat resistance and electrical properties after curing, thereby enabling the industry to receive high-value-added, high-grade circuit board materials from recycled raw materials.
[0009] One embodiment of the present disclosure provides a polycarbonate oligomer having an unsaturated double bond and having the structure shown in formula (I), [ka] However, R1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms, or a halogen atom; R2 is an alkyl group having 1 to 12 carbon atoms; and X is a single bond, a cycloalkyl group having 3 to 12 carbon atoms, or a structure shown in formula (1), formula (2), formula (3), formula (4), formula (5), formula (6), formula (7), formula (8), or formula (9). [ka] However, X1 and X2 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aromatic group having 6 to 12 carbon atoms, Y is a hydrogen atom or a methyl group, a is an integer from 0 to 4, and n is an arbitrary number from 0 to 30.
[0010] Another embodiment of the present disclosure provides a method for preparing a polycarbonate oligomer having an unsaturated double bond, the method including the following steps. An alcoholysis step is performed to dissolve a polycarbonate in a reaction solvent, and after adding a first compound and a first catalyst, an alcoholysis reaction is carried out to obtain a reaction solution of a polycarbonate oligomer having a single-sided unsaturated double bond, provided that the first compound has a structure represented by formula (II), and the polycarbonate oligomer having a single-sided unsaturated double bond has a structure represented by formula (III).
Chemical formula
[0011] An esterification step is performed to add a second compound and a second catalyst to the reaction solution, and an esterification reaction is carried out to obtain a purification target, provided that the second compound has a structure represented by formula (IV).
Chemical formula
[0012] A washing step is performed to precipitate and wash the purification target with an alcohol-based solvent to form a drying target. A drying step is performed to filter and dry the drying target to obtain a polycarbonate oligomer having an unsaturated double bond, provided that R1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms, or a halogen atom, R2 is an alkyl group having 1 to 12 carbon atoms, and X is a single bond, a cycloalkyl group having 3 to 12 carbon atoms, a structure represented by formula (1), formula (2), formula (3), formula (4), formula (5), formula (6), formula (7), formula (8), or formula (9).
Chemical formula
[0013] According to the preparation method, the molar ratio of the polycarbonate to the first compound may be 1:10 to 1:50.
[0014] According to the preparation method, the reaction solvent may be selected from the group consisting of N,N-dimethylacetamide, N-methylpyrrolidone, dimethylformamide, anisole, dimethyl sulfoxide, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, and cyclohexanone.
[0015] According to the preparation method, the first catalyst and the second catalyst may each be selected from the group consisting of 4-dimethylaminopyridine, imidazole, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 1,8-diazabicyclo[5.4.0]undeca-7-ene, and 1,5,7-triazabicyclo[4.4.0]deca-5-ene.
[0016] According to the preparation method, the molar ratio of the first compound to the first catalyst may be 1:0.002 to 1:0.004.
[0017] According to the preparation method, in the alcohol decomposition step, the polycarbonate and the first compound may be subjected to an alcohol decomposition reaction at 70°C to 180°C.
[0018] According to the preparation method, the addition amounts of the first catalyst and the second catalyst may be 10 wt% to 30 wt% of the content of the first compound.
[0019] According to the preparation method, the molar ratio of the first compound to the second compound may be 1:1 to 1:5.
[0020] According to the above preparation method, in the esterification step, the polycarbonate oligomer with a unilateral unsaturated double bond and the second compound may be esterified at 70°C to 100°C.
[0021] A further embodiment of the present disclosure provides a curable composition comprising a polycarbonate oligomer having an unsaturated double bond, a polyphenylene ether resin having an unsaturated double bond, a solvent, and a radical initiator.
[0022] According to the curable composition, the mass ratio of the polycarbonate oligomer having an unsaturated double bond to the polyphenylene ether resin having an unsaturated double bond may be 0.1 to 1.
[0023] According to the curable composition described above, the radical initiator may be selected from the group consisting of peroxides and azo initiators.
[0024] According to the curable composition, the amount of radical initiator added may be 0.5% to 3.0% by weight of the total content of the polycarbonate oligomer having an unsaturated double bond and the polyphenylene ether resin having an unsaturated double bond.
[0025] According to the curable composition, the solvent may be selected from the group consisting of N,N-dimethylacetamide, N-methylpyrrolidone, dimethylformamide, anisole, dimethyl sulfoxide, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, γ-butyrolactone, methyl ethyl ketone, cyclohexanone, toluene, and xylene.
[0026] Further embodiments of the present disclosure provide a method for preparing a low dielectric constant cured product by curing the curable composition at a curing temperature, wherein the curing temperature is 140°C to 250°C. [Effects of the Invention]
[0027] Accordingly, this disclosure proposes a method for recycling waste polycarbonate, which involves preparing a bifunctional polycarbonate oligomer having an unsaturated group at its terminus by utilizing principles such as alcohol decomposition and esterification. The oligomer can be cured together with materials commonly used in high-frequency circuit boards, and the resulting cured product has good electrical properties and physical properties, thereby achieving the goal of recycling waste and adding high value, while also meeting environmental protection requirements. [Brief explanation of the drawing]
[0028] To make the above and other purposes, features, advantages, and examples of this disclosure clearer and easier to understand, the accompanying drawings are described below. [Figure 1] This is a process flow diagram showing a method for preparing polycarbonate oligomers having unsaturated double bonds according to the present disclosure. [Modes for carrying out the invention]
[0029] The embodiments of this disclosure will be described in more detail below. However, these embodiments are applications of various inventive concepts and can be specifically implemented in various different specific scopes. Specific embodiments are for illustrative purposes only and are not limited to the scope of the disclosure.
[0030] In this disclosure, the structure of a compound may be represented by a skeleton formula, in which carbon atoms, hydrogen atoms, and carbon-hydrogen bonds may be omitted. However, if functional groups are explicitly depicted in the structural formula, those depicted shall be used as the basis.
[0031] In this disclosure, for the sake of brevity and fluency, "the first compound has the structure shown in formula (II)" may be expressed as "the first compound shown in formula (II)" or "the first compound (II)," and the same applies to the expression of other compounds or compounds.
[0032] <Polycarbonate oligomers containing unsaturated double bonds> One embodiment of the present disclosure provides a polycarbonate oligomer having an unsaturated double bond and having the structure shown in formula (I), [ka] However, R1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms, or a halogen atom; R2 is an alkyl group having 1 to 12 carbon atoms; and X is a single bond, a cycloalkyl group having 3 to 12 carbon atoms, or a structure shown in formula (1), formula (2), formula (3), formula (4), formula (5), formula (6), formula (7), formula (8), or formula (9). [ka] However, X1 and X2 are independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aromatic group having 6 to 12 carbon atoms, Y is a hydrogen atom or a methyl group, a is an integer from 0 to 4, and n is any number from 0 to 30, where n represents the degree of polymerization.
[0033] As a result, the polycarbonate oligomer having an unsaturated double bond does not contain highly polar alcohol groups in its structure, can be cured by radical polymerization, and has potential for application in products such as high-frequency circuit boards. The polycarbonate oligomer having an unsaturated double bond can be copolymerized with polyphenylene ether resins, which are currently widely used, and the cured product can have good electrical properties and heat resistance.
[0034] <Method for preparing polycarbonate oligomers containing unsaturated double bonds> Please refer to Figure 1. Figure 1 is a step flowchart showing a method 100 for preparing a polycarbonate oligomer having an unsaturated double bond according to the present disclosure. Other embodiments of the present disclosure provide the method 100 for preparing the polycarbonate oligomer having an unsaturated double bond, the method comprising steps 110, 120, 130 and 140.
[0035] Step 110 is an alcohol decomposition step, in which polycarbonate is dissolved in a reaction solvent, the first compound and the first catalyst are added, and then the alcohol decomposition reaction is carried out to obtain a reaction solution of a polycarbonate oligomer having a unilateral unsaturated double bond, wherein the first compound has the structure shown in formula (II), and the polycarbonate oligomer having a unilateral unsaturated double bond has the structure shown in formula (III). [ka]
[0036] Step 120 is an esterification step, in which the second compound and the second catalyst are added to the reaction solution, and the esterification reaction is carried out to obtain the product to be purified, wherein the second compound has the structure shown in formula (IV). [ka]
[0037] Step 130 is a washing step, in which the material to be purified is washed by precipitation with an alcohol-based solvent to form the material to be dried.
[0038] Step 140 is a drying step, in which the material to be dried is filtered and dried to obtain a polycarbonate oligomer having an unsaturated double bond. However, R1, R2, X, X1, X2, Y, a, and n in formulas (II), (III), and (IV) are as defined in the previous paragraph and will not be explained again here.
[0039] The reaction solvent may be selected from the group consisting of N,N-dimethylacetamide (DMAc), N-methylpyrrolidone (NMP), dimethylformamide (DMF), anisole, dimethyl sulfoxide (DMSO), propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, and cyclohexanone.
[0040] The first and second catalysts may be selected from the group consisting of 4-dimethylaminopyridine, imidazole, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU), and 1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD).
[0041] The molar ratio of polycarbonate to the first compound may be 1:10 to 1:50, preferably 1:20 to 1:40. The molar ratio of the first compound to the first catalyst may be 1:0.002 to 1:0.004, preferably 1:0.002 to 1:0.003. The amount of the first catalyst and the second catalyst added may be 10 to 30 weight percent of the content of the first compound, preferably 20 to 25 weight percent. The molar ratio of the first compound to the second compound may be 1:1 to 1:5, preferably 1:2.2 to 1:4.4.
[0042] Both the alcohol decomposition reaction and the esterification reaction may be carried out by heating. In the alcohol decomposition step, the polycarbonate and the first compound may undergo the alcohol decomposition reaction at 70°C to 180°C, preferably at 130°C to 150°C. In the esterification step, the polycarbonate oligomer with one-sided unsaturated double bonds and the second compound may undergo the esterification reaction at 70°C to 100°C, preferably at 70°C to 90°C.
[0043] For example, in a polycarbonate oligomer having a one-sided unsaturated double bond as shown in formula (III), if X has the structure shown in formula (1), X1, X2, and Y are methyl groups, R1 is a hydrogen atom, and R2 is an ethylene group, the prepared polycarbonate oligomer having an unsaturated double bond has the structure shown in formula (Ia), and the polycarbonate oligomer having a one-sided unsaturated double bond has the structure shown in formula (III-a). [ka]
[0044] <Curable composition> A further embodiment of the present disclosure provides a curable composition comprising a polycarbonate oligomer having an unsaturated double bond, a polyphenylene ether resin having an unsaturated double bond, a solvent, and a radical initiator, wherein the curable composition undergoes a curing reaction at high temperatures to obtain a low dielectric constant cured product. The mixing sample preparation temperature of the curable composition may be 50°C to 100°C, preferably 70°C to 90°C.
[0045] The radical initiator may be selected from the group consisting of peroxides and azo initiators, and the solvent may be selected from the group consisting of N,N-dimethylacetamide, N-methylpyrrolidone, dimethylformamide, anisole, dimethyl sulfoxide, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, γ-butyrolactone, methyl ethyl ketone, cyclohexanone, toluene, and xylene.
[0046] The mass ratio of the polycarbonate oligomer having an unsaturated double bond to the polyphenylene ether resin having an unsaturated double bond may be 0.1 to 1. The amount of radical initiator added may be 0.5 to 3.0 weight percent of the total content of the polycarbonate oligomer having an unsaturated double bond and the polyphenylene ether resin having an unsaturated double bond, preferably 1 to 2.5 weight percent. If the amount of radical initiator added is too small, it will cause incomplete curing and lead to a decrease in the physical properties of the curable composition, and if the amount added is too large, it will cause a decrease in the electrical properties of the curable composition.
[0047] <Method for preparing low dielectric constant cured materials> Further embodiments of the present disclosure provide a method for preparing a low dielectric constant cured product by curing the curable composition at a curing temperature, wherein the curing temperature is 140°C to 250°C, preferably 180°C to 220°C, but is not limited thereto, and those skilled in the art can select appropriate curing temperatures such as 140°C to 180°C, 140°C to 220°C, or 150°C to 250°C.
[0048] The following specific embodiments further illustrate the present disclosure, enabling those skilled in the art to fully utilize and practice it without undue interpretation. These embodiments should not be considered limiting to the scope of the present disclosure, but are used solely to illustrate how the materials and methods of the present disclosure are carried out.
[0049] <Preparation of polycarbonate oligomers containing unsaturated double bonds> <Example 1> 100g (4 x 10 -3 Polycarbonate pellets (purchased from Chimei Corporation, product code PC-122, Mn=24400, Mw=45488) (calculated in moles and Mn) were completely dissolved in 150g of DMAc at 150°C. Then, 10.07g (0.082 mol) of hydroxyethyl methacrylate was added dropwise to the above solution and mixed uniformly, and then 0.026g (1.69 × 10) was added. -4(1) moles of DBU were added and the mixture was reacted for 5 hours. After the reaction was complete, the temperature was lowered, the mixture was washed in methanol, filtered by suction, and dried in a vacuum oven at 78°C to obtain the compound shown in formula (III-a). The product code was HEPC, the yield was approximately 71%, and GPC analysis of the product revealed Mn=2721 and Mw=4061.
[0050] <Example 2> The first half of the process was the same as in Example 1, but after the reaction was complete, the mixture was not washed by adding it to methanol. After cooling to 70°C, 2.33 g (22% by weight of the content of compound (II)) of DBU and 27.81 g (0.180 mol) of methacrylic anhydride were added sequentially, and the mixture was reacted at 70°C for 6 hours. After the reaction was complete, the mixture was washed by adding it to methanol, filtered by suction, and dried in a vacuum oven at 78°C to obtain a white powder of formula (Ia). The product code was HAPC-1, the yield was approximately 73.6%, and GPC analysis of the product showed Mn=2366 and Mw=4137.
[0051] <Example 3> 100g (4 x 10 -3 After completely dissolving polycarbonate pellets (purchased from Chi Mei Industrial Co., Ltd., product code PC-122, Mn=24400, Mw=45488) (calculated in moles and Mn) in 150g of DMAc at 150°C, 16.51g (0.127 mol) of hydroxyethyl methacrylate was added dropwise to the above solution and mixed uniformly, then 0.038g (2.54 × 10) was added. -4 (1 / 279 mol) of DBU was added and the mixture was reacted for 5 hours. After the reaction was complete, the temperature was lowered to 70°C, and 3.63 g (22% by weight of the content of compound (II)) of DBU and 43.03 g (0.279 mol) of methacrylic anhydride were sequentially added and the mixture was reacted at 78°C for 6 hours. After the reaction was complete, the mixture was washed in methanol, filtered by suction, and dried in a vacuum oven at 78°C to obtain a white powder of formula (Ia). The product code was HAPC-1.5, the yield was approximately 59%, and GPC analysis of the product revealed Mn=2673 and Mw=4479.
[0052] <Example 4> 100 g (3.8×10 -3 mol, calculated by Mn) of recycled polycarbonate pellets (purchased from Chi Mei Industries, product code GC - 122B, Mn = 26099, Mw = 47827) were completely dissolved in 150 g of DMAc at 150 °C. Then, 14.97 g (0.115 mol) of hydroxyethyl methacrylate was dropped into the above solution. After uniformly mixing, 0.035 g (2.30×10 -4 mol) of DBU was added, and the reaction was carried out for 5 hours. After the reaction was completed, the temperature was lowered to 70 °C. Subsequently, 3.29 g (22 wt% of the content of the first compound (II)) of DBU and 39.00 g (0.253 mol) of methacrylic anhydride were added, and the reaction was carried out at 80 °C for 6 hours. After the reaction was completed, it was poured into methanol for washing, suction filtration was performed, and after drying in a vacuum oven at 78 °C, a gray powder of formula (I - a) was obtained. The product code was HAGC - 1.5, the yield was about 70.7%, and as a result of GPC analysis of the product, Mn = 2658 and Mw = 4885.
[0053] <Example 5> 100 g (3.8×10 -3 mol, calculated by Mn) of recycled polycarbonate pellets (purchased from Chi Mei Industries, product code GC - 122B, Mn = 26099, Mw = 47827) were completely dissolved in 150 g of DMAc at 150 °C. Then, 19.91 g (0.153 mol) of hydroxyethyl methacrylate was dropped into the above solution. After uniformly mixing, 0.046 g (3.02×10 -4 mol) of DBU was added, and the reaction was carried out for 5 hours. After the reaction was completed, the temperature was lowered to 80 °C. Subsequently, 4.38 g (22 wt% of the content of the first compound (II)) of DBU and 51.89 g (0.337 mol) of methacrylic anhydride were added, and the reaction was carried out at 80 °C for 6 hours. After the reaction was completed, it was poured into methanol for washing, suction filtration was performed, and after drying in a vacuum oven at 78 °C, a gray powder of formula (I - a) was obtained. The product code was HAGC - 2, the yield was about 61.9%, and as a result of GPC analysis of the product, Mn = 2257 and Mw = 4445.
[0054] <Comparative Example 1> 100g (4 x 10 -3 Polycarbonate pellets (calculated in moles and Mn) (purchased from Chi Mei Industrial Co., Ltd., product code PC-122, Mn=24400, Mw=45488) were dissolved in 150 g of DMAc, heated to 120°C to dissolve, then 7.28 g (0.0846 mol) of methacrylic acid and 0.129 g (2.47 mol) of DBU were added dropwise, and the mixture was reacted for 3 hours. After the reaction was complete, the mixture was cooled, washed in methanol, filtered by suction, and dried in a vacuum oven at 78°C to obtain a white powder with product code MAPC. The obtained product had poor solubility in organic solvents, suggesting that a radical crosslinking reaction had already occurred during the reaction process, making further manipulation and analysis impossible.
[0055] <Curing reaction of curable composition> The polycarbonate oligomer having an unsaturated double bond can be further prepared as a curable composition and subjected to a curing reaction. Specifically, a curable composition can be obtained by mixing the polycarbonate oligomer having an unsaturated double bond, a polyphenylene ether resin having an unsaturated double bond, a solvent, and a radical initiator. This allows the polycarbonate oligomer, polyphenylene ether resin, solvent, and radical initiator to form a prepolymer containing the curable composition, the details of which have been described in the previous paragraph and will not be repeated here.
[0056] Next, the polycarbonate oligomer having an unsaturated double bond and the polyphenylene ether resin can undergo a crosslinking reaction and a curing reaction through the catalytic action of a radical initiator, and this curing reaction can be completed by heating the curable composition. Specific examples are given below to illustrate this.
[0057] <Example 6> 0.24 g of polycarbonate oligomer HAPC-1 having unsaturated double bonds and 0.96 g of polyphenylene ether resin NORYL TMSA9000 (purchased from SABIC) was dissolved in 2.856 g of cyclohexanone, heated and mixed at 80°C, and then 0.024 g (2.0 weight percent of the total content of polycarbonate oligomer and polyphenylene ether resin) of dicumyl peroxide was added as a radical initiator. After homogeneous stirring, a mixed prepolymer was obtained. This was baked in an 80°C oven for 12 hours to remove part of the solvent, and then the curing reaction was carried out by gradually increasing the temperature from 140°C to 220°C to obtain a low dielectric constant cured product.
[0058] <Example 7> The preparation steps for Example 7 are the same as those for Example 6, but the amount of polycarbonate oligomer HAPC-1 having an unsaturated double bond used is changed to 0.36 g, and the polyphenylene ether resin NORYL TM The amount of SA9000 used has been changed to 0.84g.
[0059] <Example 8> The preparation steps for Example 8 are the same as in Example 6, but the amount of polycarbonate oligomer HAPC-1 having an unsaturated double bond used is changed to 0.48 g, and the polyphenylene ether resin NORYL TM The amount of SA9000 used has been changed to 0.72g.
[0060] <Example 9> The preparation steps for Example 9 are the same as in Example 6, but the amount of polycarbonate oligomer HAPC-1 having an unsaturated double bond used is changed to 0.60 g, and polyphenylene ether resin NORYL TM The amount of SA9000 used has been changed to 0.60g.
[0061] <Comparative Example 2> 0.24 g of unsaturated double-bonded polycarbonate oligomer HEPC and 0.96 g of polyphenylene ether resin NORYL TMSA9000 (purchased from SABIC) was dissolved in 2.856 g of cyclohexanone, heated and mixed at 80°C, and then 0.024 g (2.0 weight percent of the total content of polycarbonate oligomer and polyphenylene ether resin) of dicumyl peroxide was added as a radical initiator. After homogeneous stirring, a mixed prepolymer was obtained, which was baked in an 80°C oven for 12 hours to remove some of the solvent, and then the curing reaction was carried out by gradually increasing the temperature from 140°C to 220°C. After the curing reaction, significant shrinkage and phase separation were observed in the product of Comparative Example 2.
[0062] <Comparative Example 3> The preparation process for Comparative Example 3 is the same as for Comparative Example 2, but the amount of polycarbonate oligomer HEPC having an unsaturated double bond used is changed to 0.36 g, and the polyphenylene ether resin NORYL TM The amount of SA9000 used was changed to 0.84 g. After the curing reaction, significant shrinkage and phase separation were observed in the product of Comparative Example 3.
[0063] <Comparative Example 4> The preparation process for Comparative Example 4 is the same as for Comparative Example 2, but the amount of polycarbonate oligomer HEPC having an unsaturated double bond used is changed to 0.48 g, and the polyphenylene ether resin NORYL TM The amount of SA9000 used was changed to 0.72 g. After the curing reaction, significant shrinkage and phase separation were observed in the product of Comparative Example 4.
[0064] <Comparative Example 5> The preparation steps for Comparative Example 5 are the same as those for Comparative Example 2, but the amount of polycarbonate oligomer HEPC having an unsaturated double bond used is changed to 0.60 g, and the polyphenylene ether resin NORYL is used. TM The amount of SA9000 used was changed to 0.60 g. After the curing reaction, significant shrinkage and phase separation were observed in the product of Comparative Example 5.
[0065] <Property testing of low dielectric constant cured materials> The glass transition temperature (T) of the low dielectric constant cured materials obtained in Examples 6 to 9 above was measured using a differential scanning calorimeter (DSC). g The following measurements were taken. The measurement method involved setting the heating rate to 10°C / min, and the results are shown in Table 1 below. [Table 1]
[0066] Based on the results described above, the polycarbonate oligomer having an unsaturated double bond synthesized in this disclosure certainly exhibits good reactivity with polyphenylene ether resin, can react and cure under the oven conditions described above, and exhibits good compatibility and film-forming properties between the two, making processing operations easy. Furthermore, the polycarbonate oligomer having an unsaturated double bond in this disclosure can be used in combination with polyphenylene ether resin in the above ratio.
[0067] Furthermore, in terms of heat resistance, the glass transition temperature decreases with increasing amounts of polycarbonate oligomer containing unsaturated double bonds, but good heat resistance is still maintained, fully meeting the requirements of various applications.
[0068] Below, electrical property tests are performed on the low dielectric constant cured materials of Examples 6 to 9 to obtain their dielectric properties. The frequency used during the tests was 10 GHz, and the obtained dielectric constant (D k ) and dielectric loss tangent (D f These are shown in Table 2 below. [Table 2]
[0069] From the above experimental results, compared to the SA9000 cured product cured from pure polyphenylene ether resin, the low dielectric constant cured product cured by adding the polycarbonate oligomer having an unsaturated double bond synthesized in this disclosure is preferable. k It shows the characteristics, D fNo significant improvement in properties was observed. Furthermore, as can be seen from the above results, as the amount of polycarbonate oligomer with unsaturated double bonds used increases, the dielectric properties of the low dielectric constant cured material are further improved, and this leads to D f It recovers to desirable properties, and at the same time, it is superior to SA9000 cured products in terms of D k The properties obtained demonstrate the potential of the low dielectric constant cured material of this disclosure for high-frequency applications.
[0070] In summary, this disclosure provides a method for recycling waste polycarbonate, wherein polycarbonate is alcohol-decomposed using a monoalcohol compound having a double bond structure to prepare the polycarbonate as an oligomer, and then the remaining terminal phenol groups are modified to obtain a polycarbonate oligomer having unsaturated double bonds, with all terminals having unsaturated double bonds. The polycarbonate oligomer having unsaturated double bonds and the polyphenylene ether resin are compatible with organic solvents, and both can be cured by radical polymerization to prepare a sample. In the sample preparation process, desired physical properties and electrical properties can be achieved by adjusting the ratio of the polycarbonate oligomer having unsaturated double bonds and the polyphenylene ether resin, and the resulting low dielectric constant cured material exhibits good dielectric loss tangent and dielectric constant performance, and is expected to be applied to high-frequency circuit board materials.
[0071] The above examples are for illustrative purposes only and do not limit their scope. For example, other alcohols or polycarbonate resins can be used, and similar reactions can be carried out to prepare polycarbonate oligomers having unsaturated double bonds with different chemical structures. Therefore, anything obtained by slightly modifying or expanding upon the above examples falls within the scope of this disclosure.
Claims
1. A polycarbonate oligomer having an unsaturated double bond, having the structure shown in formula (I), 【Chemistry 1】 However, R １ R is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms, or a halogen atom. ２ is an alkyl group having 1 to 12 carbon atoms, and X is a single bond, a cycloalkyl group having 3 to 12 carbon atoms, or a structure shown in formula (1), formula (2), formula (3), formula (4), formula (5), formula (6), formula (7), formula (8), or formula (9). 【Chemistry 2】 However, X １ and X ２ Each of these is independently a hydrogen atom, a C1-C6 alkyl group, or a C6-C12 aromatic group. A polycarbonate oligomer having an unsaturated double bond, characterized in that Y is a hydrogen atom or a methyl group, a is an integer from 0 to 4, and n is any number from 0 to 30.
2. A method for preparing a polycarbonate oligomer having an unsaturated double bond as described in claim 1, The alcohol decomposition step involves dissolving polycarbonate in a reaction solvent, adding a first compound and a first catalyst, and then carrying out an alcohol decomposition reaction to obtain a reaction solution of a polycarbonate oligomer having a one-sided unsaturated double bond, wherein the first compound has the structure shown in formula (II), and the polycarbonate oligomer having a one-sided unsaturated double bond has the structure shown in formula (III). 【Transformation 3】 The esterification step involves adding the second compound and the second catalyst to the reaction solution and carrying out an esterification reaction to obtain the product to be purified, wherein the second compound has the structure shown in formula (IV). 【Chemistry 4】 The washing process involves precipitating and washing the aforementioned material to be purified with an alcohol-based solvent to form a material to be dried. A drying step is performed in which the material to be dried is filtered and dried to obtain the polycarbonate oligomer having the unsaturated double bond. Includes, However, R １ R is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an allyl group, an alkoxy group having 1 to 6 carbon atoms, an aromatic group having 6 to 12 carbon atoms, or a halogen atom. ２ is an alkyl group having 1 to 12 carbon atoms, and X is a single bond, a cycloalkyl group having 3 to 12 carbon atoms, or a structure shown in formula (1), formula (2), formula (3), formula (4), formula (5), formula (6), formula (7), formula (8), or formula (9). 【Transformation 5】 However, X １ and X ２ Each of these is independently a hydrogen atom, a C1-C6 alkyl group, or a C6-C12 aromatic group. A method for preparing a polycarbonate oligomer having an unsaturated double bond, characterized in that Y is a hydrogen atom or a methyl group, a is an integer from 0 to 4, and n is any number from 0 to 30.
3. The preparation method according to claim 2, characterized in that the molar ratio of the polycarbonate to the first compound is 1:10 to 1:
50.
4. The preparation method according to claim 2, characterized in that the reaction solvent is selected from the group consisting of N,N-dimethylacetamide, N-methylpyrrolidone, dimethylformamide, anisole, dimethyl sulfoxide, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, and cyclohexanone.
5. The preparation method according to claim 2, characterized in that the first catalyst and the second catalyst are each selected from the group consisting of 4-dimethylaminopyridine, imidazole, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 1,8-diazabicyclo[5.4.0]undeca-7-ene, and 1,5,7-triazabicyclo[4.4.0]deca-5-ene.
6. The preparation method according to claim 2, characterized in that the molar ratio of the first compound to the first catalyst is 1:0.002 to 1:0.
004.
7. The preparation method according to claim 2, characterized in that, in the alcohol decomposition step, the polycarbonate and the first compound undergo an alcohol decomposition reaction at 70°C to 180°C.
8. The preparation method according to claim 2, characterized in that the amount of the first catalyst and the second catalyst added is 10% by weight to 30% by weight of the content of the first compound.
9. The preparation method according to claim 2, characterized in that the molar ratio of the first compound to the second compound is 1:1 to 1:
5.
10. The preparation method according to claim 2, characterized in that, in the esterification step, the polycarbonate oligomer with one-sided unsaturated double bonds and the second compound are subjected to an esterification reaction at 70°C to 100°C.
11. A curable composition comprising a polycarbonate oligomer having an unsaturated double bond as described in claim 1, a polyphenylene ether resin having an unsaturated double bond, a solvent, and a radical initiator.
12. The curable composition according to claim 11, characterized in that the mass ratio of the polycarbonate oligomer having the unsaturated double bond to the polyphenylene ether resin having the unsaturated double bond is 0.1 to 1.
13. The curable composition according to claim 11, characterized in that the radical initiator is selected from the group consisting of peroxides and azo initiators.
14. The curable composition according to claim 11, characterized in that the amount of the radical initiator added is 0.5% to 3.0% by weight of the total content of the polycarbonate oligomer having an unsaturated double bond and the polyphenylene ether resin having an unsaturated double bond.
15. The curable composition according to claim 11, characterized in that the solvent is selected from the group consisting of N,N-dimethylacetamide, N-methylpyrrolidone, dimethylformamide, anisole, dimethyl sulfoxide, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, γ-butyrolactone, methyl ethyl ketone, cyclohexanone, toluene, and xylene.
16. A method for preparing a low dielectric constant cured product, characterized by curing the curable composition described in claim 11 at a curing temperature of 140°C to 250°C to obtain a low dielectric constant cured product.