Modified unsaturated polyester resin as well as preparation method and application thereof

Abstract

The invention provides modified unsaturated polyester resin as well as a preparation method and application thereof, the modified unsaturated polyester resin is a blend of unsaturated polyester resin and hydroxyl-containing cyano resin, and the modified unsaturated polyester resin is prepared by blending and modifying the unsaturated polyester resin and the hydroxyl-containing cyano resin. According to the invention, the hydroxyl-containing cyano resin modified unsaturated polyester resin is introduced, and the structure of the hydroxyl-containing cyano resin modified unsaturated polyester resin contains the hydroxyl with catalytic activity, so that the hydroxyl-containing cyano resin modified unsaturated polyester resin can be cured at a lower temperature, can be dissolved in styrene and has good compatibility with an unsaturated polyester resin system. The thermal property, the mechanical property and the flame retardant property of the unsaturated polyester resin are greatly improved by introducing the hydroxyl-containing cyano resin, an initiator does not need to be additionally added, and a modified resin system is suitable for various forming processes.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials and relates to a modified unsaturated polyester resin and a preparation method and application thereof. Background Art

[0002] Unsaturated polyester resin is a commonly used thermosetting resin, usually made by polycondensation of unsaturated dibasic acid, saturated dibasic acid and diol. In its molecular structure, it contains unsaturated double bonds, which can cross-link and copolymerize to form a three-dimensional network structure, thereby solidifying into an insoluble and infusible solid. Styrene is the most commonly used cross-linking agent, which can also reduce the viscosity of unsaturated polyester resin, adjust the curing properties of the resin, and improve wettability.

[0003] Unsaturated polyester resin has good process performance and can be made into products of various shapes and sizes through a variety of molding processes. Its cured products have good corrosion resistance and electrical insulation, and its cost is relatively low, the raw materials are widely available, and the price is relatively affordable, which makes it economically advantageous in large-scale production. However, the curing shrinkage of unsaturated polyester resin is large, and its heat resistance, weather resistance, and ablation resistance need to be further improved. Initiators need to be added to the resin system, which is not conducive to improving its various properties.

[0004] Cyanoresin is a type of thermosetting resin containing -CN groups. Its cured product has a high crosslink density and good chemical corrosion resistance, heat resistance, mechanical properties, and ablation resistance. However, cyanoresin has poor processing performance, is mostly solid at room temperature, has a high melting point, and requires very high temperatures to fully cure.

[0005] Therefore, it is desirable in the art to develop an unsaturated polyester resin having good heat resistance, mechanical properties and flame retardant properties. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a modified unsaturated polyester resin and a preparation method and application thereof. The present invention prepares a modified unsaturated polyester resin by blending and modifying an unsaturated polyester resin and a hydroxyl-containing cyano resin, which can be widely used in the fields of petroleum, chemical industry, etc.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In one aspect, the present invention provides a modified unsaturated polyester resin, wherein the modified unsaturated polyester resin is a blend of an unsaturated polyester resin and a hydroxyl-containing cyano resin; the structure of the hydroxyl-containing cyano resin is as follows:

[0009]

[0010] Wherein n is an integer of 20-40, for example, 20, 22, 24, 26, 28, 30, 32, 34, 35, 38 or 40, etc.

[0011] In the present invention, a modified unsaturated polyester resin is prepared by blending and modifying an unsaturated polyester resin and a hydroxyl-containing cyano resin. The present invention introduces a hydroxyl-containing cyano resin modified unsaturated polyester resin. Since its structure contains hydroxyl groups with catalytic activity, it can be cured at a lower temperature and can be dissolved in styrene, so it has good compatibility with the unsaturated polyester resin system. The introduction of the hydroxyl-containing cyano resin greatly improves the thermal properties, mechanical properties and flame retardant properties of the unsaturated polyester resin, and there is no need to add an initiator. The modified resin system is suitable for a variety of molding processes.

[0012] Preferably, the unsaturated polyester resin includes any one of orthophthalic unsaturated polyester resin, isophthalic unsaturated polyester resin, para-terephthalic unsaturated polyester resin, bisphenol A unsaturated polyester resin or vinyl ester unsaturated polyester resin, or a combination of at least two thereof.

[0013] Preferably, the mass ratio of the unsaturated polyester resin to the hydroxyl-containing cyano resin is 100:(5-20), for example, 100:5, 100:6, 100:7, 100:8, 100:9, 100:10, 100:11, 100:12, 100:13, 100:14, 100:15, 100:16, 100:17, 100:18, 100:19 or 100:20.

[0014] In the present invention, the hydroxyl-containing cyano resin is used as the main modification component. A small amount of addition cannot effectively improve the performance of the unsaturated polyester resin, while a large amount of addition will lead to greater cost pressure and is not conducive to industrial expansion of production.

[0015] After the unsaturated polyester resin is diluted by adding styrene, the viscosity and processing process of the resin can be regulated, and it has good process performance, but the heat resistance and ablation resistance still need to be improved. Based on this, the present invention provides a hydroxyl-containing cyano resin modified unsaturated polyester resin. The hydroxyl-containing cyano resin has good solubility in styrene. Therefore, in the unsaturated polyester resin obtained after blending and modification, the cyano resin and the unsaturated polyester resin have good compatibility and are suitable for a variety of processing techniques. The cured product has good heat resistance, which provides a new idea for preparing high-performance composite materials.

[0016] On the other hand, the present invention provides a method for preparing the modified unsaturated polyester resin as described above, the preparation method comprising the following steps:

[0017] The unsaturated polyester resin and the hydroxyl-containing cyano resin are stirred and mixed under the protection of an inert gas, and the hydroxyl-containing cyano resin is uniformly dissolved in the unsaturated polyester resin to obtain the modified unsaturated polyester resin.

[0018] Preferably, the inert gas is nitrogen.

[0019] Preferably, the stirring is carried out at room temperature (20-35°C, for example 20°C, 22°C, 25°C, 28°C, 30°C, 33°C or 35°C), and the stirring time is 1 to 5 h, for example 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, 4 h, 4.5 h or 5 h, preferably 1 to 3 h.

[0020] In another aspect, the present invention provides a modified unsaturated polyester resin cured product, wherein the cured product is obtained by curing the modified unsaturated polyester resin as described above.

[0021] In another aspect, the present invention provides a laminated board, comprising a reinforcing material and a resin matrix, wherein the resin matrix is ​​the modified unsaturated polyester resin as described above.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention provides an unsaturated polyester resin modified by a hydroxyl-containing cyano resin. Compared with a traditional unsaturated polyester resin system, the present invention does not require the addition of an initiator, can greatly improve the heat resistance and mechanical properties of the unsaturated polyester resin, and the two resin components have good compatibility, are suitable for various molding processes, have excellent processing performance, and are conducive to the preparation of various high-performance composite materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 2123 phenolic resin before and after reaction 1 H-NMR spectrum;

[0025] Figure 2 For hydroxyl-containing cyano resin 13 C-NMR spectrum. DETAILED DESCRIPTION

[0026] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0027] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0028] In the following examples, the hydroxyl-containing cyano resin used has the following structure:

[0029]

[0030] Using 2123 phenolic resin from Henan Jieyang New Materials Co., Ltd. as the main body, add 2123 phenolic resin (21.6g), 4-nitrophthalonitrile (20.8g), and DMF (80ml) into a four-necked flask with nitrogen, a stirrer, a thermometer, and a condenser, and stir until dissolved. Add K2CO3 (16.6g), heat to 80°C, and keep warm for 8h. Slowly pour the reaction solution into 2000ml of water, the product precipitates, use dilute hydrochloric acid to adjust the system pH to neutral, wash twice with water, and vacuum dry the solid obtained by suction at 80°C for 24h to obtain a light yellow powder solid.

[0031] 2123 phenolic resin before and after reaction 1 H-NMR spectrum Figure 1 The prepared hydroxyl-containing cyano resin 13 C-NMR spectrum Figure 2 shown.

[0032] Example 1

[0033] Hydroxyl cyanide resin modified unsaturated polyester resin, and preparation of cured products and composite materials thereof:

[0034] (1) 100 g of isophthalic unsaturated polyester resin (TM-52001, Changzhou Tianma Group Co., Ltd.) and 10 g of hydroxyl-containing cyano resin were added to a dry four-necked flask and stirred at room temperature for 2 h under nitrogen protection. The hydroxyl-containing cyano resin was uniformly dissolved in the unsaturated polyester resin to obtain a hydroxyl-containing cyano resin modified unsaturated polyester resin.

[0035] (2) placing the product obtained in step (1) in a mold, curing it in a vacuum oven under the conditions of 160° C. / 2 h+180° C. / 2 h+200° C. / 2 h, and cooling the oven to room temperature to obtain a hydroxyl-containing cyano resin-modified unsaturated polyester resin cured product.

[0036] (3) The product obtained in step (1) is used as a resin matrix and a glass fiber plain woven cloth is used as a reinforcing material. The resin matrix is ​​dissolved in tetrahydrofuran and evenly coated on the glass fiber reinforcing material to prepare a glass fiber reinforced modified unsaturated polyester resin prepreg. A glass fiber reinforced modified unsaturated polyester resin laminate (i.e., a composite material) is prepared by compression molding, wherein the resin content is 40%. During the compression molding process, the temperature is raised in a stepwise manner of 160° C. / 2 h+180° C. / 2 h+200° C. / 2 h.

[0037] According to GB / T 27761-2011, the above-mentioned solidified material was tested in a nitrogen atmosphere at a heating rate of 10°C / min, and the thermal decomposition temperature T d5 It is 362℃.

[0038] According to GB / T 1449-2005 and GB / T 1447-2005, the flexural strength of the composite material is 400.5MPa and the tensile strength is 331.8MPa. The flexural strength of the general unsaturated polyester resin GFRP is 284MPa and the tensile strength is 233MPa.

[0039] Example 2

[0040] Hydroxyl cyanide resin modified unsaturated polyester resin, and preparation of cured products and composite materials thereof:

[0041] (1) 100 g of o-phthalic unsaturated polyester resin (TM-196, produced by Changzhou Tianma Group Co., Ltd.) and 5 g of hydroxyl-containing cyano resin were added to a dry four-necked flask and stirred at room temperature for 1 h under nitrogen protection. The hydroxyl-containing cyano resin was uniformly dissolved in the unsaturated polyester resin to obtain a hydroxyl-containing cyano resin modified unsaturated polyester resin.

[0042] (2) placing the product obtained in step (1) in a mold, curing it in a vacuum oven under the conditions of 160° C. / 2 h+180° C. / 2 h+200° C. / 2 h, and cooling the oven to room temperature to obtain a hydroxyl-containing cyano resin-modified unsaturated polyester resin cured product.

[0043] (3) The product obtained in step (1) is used as a resin matrix and a glass fiber plain woven cloth is used as a reinforcing material. The resin matrix is ​​dissolved in tetrahydrofuran and evenly coated on the glass fiber reinforcing material to prepare a glass fiber reinforced modified unsaturated polyester resin prepreg. A glass fiber reinforced modified unsaturated polyester resin laminate (i.e., a composite material) is prepared by compression molding, wherein the resin content is 40%. During the compression molding process, the temperature is raised in a stepwise manner of 160° C. / 2 h+180° C. / 2 h+200° C. / 2 h.

[0044] According to GB / T 27761-2011, the above-mentioned solidified material was tested in a nitrogen atmosphere at a heating rate of 10°C / min, and the thermal decomposition temperature T d5 It is 324℃.

[0045] According to GB / T 1449-2005 and GB / T 1447-2005, the flexural strength of the composite material is 375.5MPa and the tensile strength is 302.4MPa. The flexural strength of the general unsaturated polyester resin GFRP is 284MPa and the tensile strength is 233MPa.

[0046] Example 3

[0047] Hydroxyl cyanide resin modified unsaturated polyester resin, and preparation of cured products and composite materials thereof:

[0048] (1) 100 g of a terephthalate unsaturated polyester resin (SWANCOR 961, Shangwei New Materials Co., Ltd.) and 20 g of a hydroxyl-containing cyano resin were added to a dry four-necked flask, and stirred at room temperature for 3 h under nitrogen protection. The hydroxyl-containing cyano resin was uniformly dissolved in the unsaturated polyester resin, thereby obtaining a hydroxyl-containing cyano resin modified unsaturated polyester resin.

[0049] (2) placing the product obtained in step (1) in a mold, curing it in a vacuum oven by stepwise heating at 160°C / 2h+180°C / 2h+200°C / 2h, and cooling the oven to room temperature to obtain a cured unsaturated polyester resin modified with a hydroxy cyanide resin.

[0050] (3) The product obtained in step (1) is used as a resin matrix and a glass fiber plain woven cloth is used as a reinforcing material. The resin matrix is ​​dissolved in tetrahydrofuran and evenly coated on the glass fiber reinforcing material to prepare a glass fiber reinforced modified unsaturated polyester resin prepreg. A glass fiber reinforced modified unsaturated polyester resin laminate (i.e., a composite material) is prepared by compression molding, wherein the resin content is 40%. During the compression molding process, the temperature is raised in a stepwise manner of 160° C. / 2 h+180° C. / 2 h+200° C. / 2 h.

[0051] According to GB / T 27761-2011, the above-mentioned solidified material was tested in a nitrogen atmosphere at a heating rate of 10°C / min, and the thermal decomposition temperature T d5 It is 376℃.

[0052] According to GB / T 1449-2005 and GB / T 1447-2005, the flexural strength of the composite material is 417.7MPa and the tensile strength is 348.6MPa. The flexural strength of the general unsaturated polyester resin GFRP is 284MPa and the tensile strength is 233MPa.

[0053] Example 4

[0054] Hydroxyl cyanide resin modified unsaturated polyester resin, and preparation of cured products and composite materials thereof:

[0055] (1) 100 g of bisphenol A type unsaturated polyester resin (TM-197, Changzhou Tianma Group Co., Ltd.) and 15 g of hydroxyl-containing cyano resin were added to a dry four-necked flask and stirred at room temperature for 5 h under nitrogen protection. The hydroxyl-containing cyano resin was uniformly dissolved in the unsaturated polyester resin to obtain a hydroxyl-containing cyano resin modified unsaturated polyester resin.

[0056] (2) placing the product obtained in step (1) in a mold, curing it in a vacuum oven by stepwise heating at 160°C / 2h+180°C / 2h+200°C / 2h, and cooling the oven to room temperature to obtain a cured unsaturated polyester resin modified with a hydroxy cyanide resin.

[0057] (3) The product obtained in step (1) is used as a resin matrix and a glass fiber plain woven cloth is used as a reinforcing material. The resin matrix is ​​dissolved in tetrahydrofuran and evenly coated on the glass fiber reinforcing material to prepare a glass fiber reinforced modified unsaturated polyester resin prepreg. A glass fiber reinforced modified unsaturated polyester resin laminate (i.e., a composite material) is prepared by compression molding, wherein the resin content is 40%. During the compression molding process, the temperature is raised in a stepwise manner of 160° C. / 2 h+180° C. / 2 h+200° C. / 2 h.

[0058] According to GB / T 27761-2011, the above-mentioned solidified material was tested in a nitrogen atmosphere at a heating rate of 10°C / min, and the thermal decomposition temperature T d5 It is 370℃.

[0059] According to GB / T 1449-2005 and GB / T 1447-2005, the flexural strength of the composite material is 406.9MPa and the tensile strength is 335.8MPa. The flexural strength of the general unsaturated polyester resin GFRP is 284MPa and the tensile strength is 233MPa.

[0060] Example 5

[0061] Hydroxyl cyanide resin modified unsaturated polyester resin, and preparation of cured products and composite materials thereof:

[0062] (1) 100 g of vinyl ester type unsaturated polyester resin (TM-V280 produced by Changzhou Tianma Group Co., Ltd.) and 8 g of hydroxyl-containing cyano resin were added to a dry four-necked flask and stirred at room temperature for 3 h under nitrogen protection. The hydroxyl-containing cyano resin was uniformly dissolved in the unsaturated polyester resin to obtain a hydroxyl-containing cyano resin modified unsaturated polyester resin.

[0063] (2) placing the product obtained in step (1) in a mold, curing it in a vacuum oven by stepwise heating at 160°C / 2h+180°C / 2h+200°C / 2h, and cooling the oven to room temperature to obtain a cured unsaturated polyester resin modified with a hydroxy cyanide resin.

[0064] (3) The product obtained in step (1) is used as a resin matrix and a glass fiber plain woven cloth is used as a reinforcing material. The resin matrix is ​​dissolved in tetrahydrofuran and evenly coated on the glass fiber reinforcing material to prepare a glass fiber reinforced modified unsaturated polyester resin prepreg. A glass fiber reinforced modified unsaturated polyester resin laminate (i.e., a composite material) is prepared by compression molding, wherein the resin content is 40%. During the compression molding process, the temperature is raised in a stepwise manner of 160° C. / 2 h+180° C. / 2 h+200° C. / 2 h.

[0065] According to GB / T 27761-2011, the above-mentioned solidified material was tested in a nitrogen atmosphere at a heating rate of 10°C / min, and the thermal decomposition temperature T d5 It is 340℃.

[0066] According to GB / T 1449-2005 and GB / T 1447-2005, the flexural strength of the composite material is 386.6MPa and the tensile strength is 304.2MPa. The flexural strength of the general unsaturated polyester resin GFRP is 284MPa and the tensile strength is 233MPa.

[0067] The applicant declares that the present invention uses the above embodiments to illustrate the unsaturated polyester resin and its preparation method and application, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A modified unsaturated polyester resin, characterized in that: The modified unsaturated polyester resin is a blend of an unsaturated polyester resin and a hydroxyl-containing cyano resin; the structure of the hydroxyl-containing cyano resin is as follows: Wherein n is an integer from 20 to 40.

2. The modified unsaturated polyester resin according to claim 1, characterized in that The unsaturated polyester resin includes any one of orthophthalic unsaturated polyester resin, isophthalic unsaturated polyester resin, paraphthalic unsaturated polyester resin, bisphenol A unsaturated polyester resin or vinyl ester unsaturated polyester resin, or a combination of at least two thereof.

3. The modified unsaturated polyester resin according to claim 1 or 2, characterized in that: The mass ratio of the unsaturated polyester resin to the hydroxyl-containing cyano resin is 100:(5-20).

4. The method for preparing a modified unsaturated polyester resin according to any one of claims 1 to 3, characterized in that: The preparation method comprises the following steps: The unsaturated polyester resin and the hydroxyl-containing cyano resin are stirred and mixed under the protection of an inert gas, and the hydroxyl-containing cyano resin is uniformly dissolved in the unsaturated polyester resin to obtain the modified unsaturated polyester resin.

5. The preparation method according to claim 4, characterized in that: The inert gas is nitrogen.

6. The preparation method according to claim 4, characterized in that: The stirring is carried out at room temperature for 1 to 5 hours.

7. The preparation method according to claim 6, characterized in that: The stirring time is 1 to 3 hours.

8. A modified unsaturated polyester resin cured product, characterized in that: The cured product is obtained by curing the modified unsaturated polyester resin according to any one of claims 1 to 3.

9. A laminated board, characterized in that: The laminate comprises a reinforcing material and a resin matrix, and the resin matrix is ​​the modified unsaturated polyester resin according to any one of claims 1 to 3.

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