Halogen-free flame-retardant epoxy resin system composition and application

Abstract

The invention discloses a halogen-free flame-retardant epoxy resin system composition and application, the epoxy resin system composition is composed of an epoxy resin part and a curing agent part, the epoxy resin part is composed of dihydroxydiphenylmethane glycidyl ether, 2, 2 '-[(1-methylethylene) bis (4, 1-phenylene formaldehyde)] dioxirane, 2, 2'-dihydroxydiphenylmethane glycidyl ether, 2, 2 '-[(1-methylethylene) bis (4, 1-phenylene formaldehyde)] dioxirane, 2, 2'-dihydroxydiphenylmethane, 2, 2 '-dihydroxydiphenylmethane, the halogen-free flame retardant is composed of hydroxyl-terminated polysiloxane modified bisphenol A glycidyl ether, an organophosphorus flame retardant, an active diluent and an auxiliary agent. And the curing agent part consists of an alicyclic amine curing agent, amine-terminated polyether and an accelerant. The epoxy resin system composition provided by the invention is low in mixing viscosity and strong in operability, a cured product has excellent toughness and heat resistance while ensuring that the flame retardant grade meets UL94V0, and the problems that a halogen-free flame-retardant system is poor in process operability, the performance of the cured product is reduced, halogen elements can release harmful gas at high temperature, and the service life of the cured product is prolonged can be effectively solved. And harm to human health and environment is caused.

Description

Technical Field

[0001] This invention relates to a halogen-free flame-retardant epoxy resin system composition for fiber composite materials, belonging to the field of organic polymer materials. Background Technology

[0002] Epoxy resin is a type of thermosetting polymer synthetic material with excellent adhesion, corrosion resistance, insulation, and high strength. It has been widely used in the bonding of various metals and non-metals, corrosion-resistant coatings, electrical insulation materials, and the manufacture of fiberglass / composite materials. It plays a vital role in electronics, electrical engineering, machinery manufacturing, chemical corrosion protection, aerospace, shipbuilding, chemical building materials, hydropower generation, and many other industrial fields, and has become an indispensable basic material in various industrial sectors.

[0003] Epoxy resin is one of the more flammable thermosetting resins. The oxygen index of ordinary epoxy resin is only around 19.8, so flame retardant treatment is necessary. Currently, the main technical approach to preparing flame-retardant epoxy resins is modification by adding flame retardants to the epoxy resin system. Two common types are halogenated flame retardants and halogen-free flame retardants. Halogenated flame retardants have high flame retardant efficiency, but they are very unfriendly to the products and the environment, and their application has been restricted in many fields. Therefore, halogen-free flame retardants are currently more commonly used. Compared with halogenated flame retardants, halogen-free flame retardants have relatively lower flame retardant efficiency. To achieve a certain flame retardant performance, the amount of flame retardant needs to be increased. This affects the processing performance of the epoxy resin system, and excessive use of flame retardant can also adversely affect the gel curing of the material, impacting its curing properties. Summary of the Invention

[0004] To address the shortcomings in existing product applications, the first objective of this invention is to provide a halogen-free flame-retardant epoxy resin composition. This epoxy resin composition, when prepared into an adhesive solution, has suitable viscosity, good processability, and exhibits good mechanical properties and heat resistance after curing. It also meets the high flame-retardant rating of the UL94 standard. Furthermore, its preparation process is simple and suitable for large-scale production.

[0005] A second objective of this invention is to provide an application of a halogen-free flame-retardant epoxy resin system composition.

[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0007] This invention provides a halogen-free flame-retardant epoxy resin system composition, which comprises an epoxy resin portion and a curing agent portion. The epoxy resin portion consists of dihydroxydiphenylmethane glycidyl ether, 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bisepoxyethylene, hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether, organophosphorus flame retardant, epoxy-based reactive diluent, and additives. The curing agent portion consists of alicyclic amine curing agent, polyetheramine curing agent, and accelerator.

[0008] The halogen-free flame-retardant epoxy resin system composition provided by this invention possesses the dual properties of inorganic compounds and organic polymers through its polysiloxane structure. The hydroxyl-terminated polysiloxane-modified epoxy resin (hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether) contains silicon. Under high-temperature and combustion environments, the modified epoxy can form a silicon / oxygen / carbon structure, reducing the formation of volatile carbonaceous substances and improving the resin's ablation resistance, flame retardancy, and high-temperature residual strength. The organophosphorus flame retardant not only increases the carbon residue but also prevents carbon from being oxidized to carbon dioxide, thereby reducing the heat released by oxidation. The reactive diluent is a bifunctional glycidyl ether, which effectively reduces the system viscosity and improves the product's processability. Simultaneously, the reactive diluent contains epoxy groups that can participate in the curing reaction, ensuring the performance of the cured product. The mixed additives are a mixture of defoamers, fiber wetting agents, and other additives. The defoamer promotes bubble elimination during product application, reducing the porosity of the cured product; the fiber wetting agent increases the system's wetting speed on fibers, avoiding problems such as white spots and incomplete wetting during composite material preparation.

[0009] In the curing agent portion of this invention, both alicyclic amine curing agent and polyether amine curing agent are used. The alicyclic amine curing agent has good heat resistance, while the polyether amine has good toughness. After the epoxy resin portion and the curing agent portion are cured, the resulting epoxy resin system composition will form a silicon-phosphorus synergistic effect during the combustion process, further achieving a flame retardant effect.

[0010] As a preferred embodiment, the epoxy resin portion, by mass ratio, comprises: dihydroxydiphenylmethane glycidyl ether: 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide): hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether: organophosphorus flame retardant: epoxy-based reactive diluent: additives = 0-30: 20-60: 12-25: 5-15: 5-15: 0.2-1.

[0011] In the epoxy resin portion of this invention, the amount of additive flame retardant is reduced, and a siloxane-modified epoxy with flame-retardant properties is introduced. This modified epoxy can participate in the reaction, thereby ensuring the curing performance.

[0012] As a further preferred embodiment, the epoxy resin portion, by mass ratio, comprises: dihydroxydiphenylmethane glycidyl ether: 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide): hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether: organophosphorus flame retardant: epoxy-based reactive diluent: additives = 15-30: 35-50: 12-20: 8-10: 10-13: 0.2-1.

[0013] As a preferred embodiment, the dihydroxydiphenylmethane glycidyl ether has an epoxy equivalent of 160-180 g / eq and a viscosity of 2000-5000 mPa·s.

[0014] As a preferred embodiment, the epoxy equivalent of the 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bisepoxyethylene is 170-180 g / eq. In this invention, the 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bisepoxyethylene is a homopolymer. Controlling the epoxy equivalent within the above range ensures suitable processability of the system.

[0015] As a preferred embodiment, the hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether is prepared by reacting hydroxyl-terminated polyphenylpropylsiloxane with bisphenol A type epoxy resin.

[0016] As a preferred embodiment, the organophosphorus flame retardant resin is selected from at least one of aliphatic phosphate esters, phosphate ester compounds, condensed phosphate esters, and phosphonates.

[0017] As a preferred embodiment, the epoxy-based reactive diluent is selected from at least one of 1,4-bis(2,3-epoxypropoxy)butane and 1,6-bis(2,3-epoxypropoxy)hexane.

[0018] As a preferred embodiment, the additive is selected from defoamers and / or release agents, wherein the defoamer is selected from at least one of emulsified silicone oil, higher carbon alcohol fatty acid ester complex, polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropylene alcohol amine ether, polyoxypropylene glycerol ether, polyoxypropylene polyoxyethylene glycerol ether, and polydimethylsiloxane, and the release agent is selected from at least one of epoxy-modified silicone oil, polyvinyl alcohol, and polyisobutylene.

[0019] As a preferred embodiment, the curing agent portion, by mass ratio, is alicyclic amine curing agent: polyether amine curing agent: accelerator = 75-90: 10-25: 1-2. The amount of accelerator affects the reaction rate during the use of the composition; therefore, it is necessary to maintain an appropriate ratio to obtain optimal processing performance.

[0020] As a preferred embodiment, the cycloaliphatic amine curing agent is selected from at least one of 5-amino-1,3,3-trimethylcyclohexylmethylamine and 4,4'-diaminodicyclohexylmethane.

[0021] As a preferred embodiment, the polyetheramine curing agent is polyether diamine or polyether triamine with a molecular weight between 200 and 5000.

[0022] As a preferred embodiment, the accelerator is selected from at least one of N,N-dimethylbenzylamine and DMP-30.

[0023] As a preferred embodiment, the preparation process of the epoxy resin component is as follows: hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether, dihydroxydiphenylmethane glycidyl ether, 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide), hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether, organophosphorus flame retardant, epoxy-based reactive diluent, and additives are heated to 50-70℃ and stirred for 60-90 minutes, then cooled to 40-50℃ and discharged to obtain the final product.

[0024] As a preferred embodiment, the preparation process of the curing agent is as follows: the alicyclic amine curing agent, the polyether amine curing agent, and the accelerator are added into the reaction vessel in proportion, heated to 40-60℃ and stirred for 50-70 minutes, and then cooled to 35-45℃ to obtain the curing agent.

[0025] In a preferred embodiment, the mass ratio of the epoxy resin component to the curing agent component in the epoxy resin system composition is 100:15-25.

[0026] In a preferred embodiment, the epoxy resin system composition is obtained by mixing the epoxy resin portion and the curing agent portion, and then curing it. The curing conditions are as follows: first, heat treatment at 60-70℃ for 1 hour, and then heat treatment at 90-100℃ for 5-6 hours.

[0027] The present invention also provides an application of a halogen-free flame-retardant epoxy resin system composition, wherein the halogen-free flame-retardant epoxy resin system composition is used to prepare fiber epoxy resin composite materials.

[0028] Beneficial effects

[0029] The epoxy resin composition prepared by this invention has good operability, and its cured product has the characteristics of high strength, high toughness, and good weather resistance. It can be used to prepare epoxy resin composite parts with halogen-free flame retardant requirements.

[0030] The epoxy resin composition prepared by this invention has the following characteristics: 1) good processability, with an initial viscosity of 200-400 mPa·s and a room temperature operating time of >50 min; 3) the cured product has high strength and high toughness, with a tensile strength >75 MPa, elongation at break >4%, and glass transition temperature >90℃; 4) the cured product of the composition achieves a UL94V0 flame retardant rating.

[0031] The method for preparing epoxy resin composite materials according to the present invention uses readily available raw materials, has low cost, and simple process steps, which is conducive to large-scale production and application. Detailed Implementation

[0032] To further understand the present invention, preferred embodiments are described below with reference to examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, and not for limiting the scope of the claims. The main raw materials involved in the examples and comparative examples are as follows:

[0033] Dihydroxydiphenylmethane glycidyl ether: Nan Ya Electronic Materials (Kunshan) Co., Ltd.; 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide): Sinopec Hunan Petrochemical Co., Ltd.; 1,4-bis(2,3-epoxypropoxy)butane, 1,6-bis(2,3-epoxypropoxy)hexane: Anhui Xinyuan Co., Ltd.; Organophosphorus flame retardant: Shandong Xinghai Chemical Co., Ltd.; Alicyclic amine curing agent: Wanhua Chemical; Amino-terminated polyether: Changde Chemical; 2,4,6-tris(dimethylaminomethyl)phenol (DMP-30): Sinopharm Group.

[0034] To better understand the present invention, the present invention will be further described in detail with reference to the embodiments, but the scope of protection of the present invention is not limited to the scope shown in the embodiments.

[0035] Example 1

[0036] Component A (i.e., the epoxy resin portion) is in the following mass ratio:

[0037] Dihydroxydiphenylmethane glycidyl ether: 30

[0038] 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide): 35

[0039] Hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether: 20

[0040] Organophosphorus flame retardant (dibutyl phosphate): 8

[0041] 1,4-Bis(2,3-epoxypropoxy)butane:8

[0042] Additive (polydimethylsiloxane): 0.2

[0043] Component B (i.e., the curing agent portion) is in the following mass ratio:

[0044] IPDA (5-amino-1,3,3-trimethylcyclohexylamine): 88.8

[0045] T-403 (Polyetheramine): 10

[0046] N,N-dimethylbenzylamine: 1.2

[0047] Preparation method of epoxy resin composition:

[0048] The preparation method of component A is as follows: add the prescribed amounts of dihydroxydiphenylmethane glycidyl ether, 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide) homopolymer, hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether, organophosphorus flame retardant, reactive diluent, and additives to a container, heat to 40-60℃ and stir at high speed for 60 minutes, then cool to room temperature to obtain epoxy resin component A.

[0049] The preparation method of component B is as follows: First, the alicyclic amine curing agent, terminal amino polyether, and accelerator are added into the reaction vessel in proportion, heated to 40℃-60℃ and stirred for 60 minutes, and then cooled to room temperature to obtain curing agent component B.

[0050] When using, take component A and component B and mix them evenly in a mass ratio of 100:23.

[0051] Example 2

[0052] Component A (i.e., the epoxy resin portion) is in the following mass ratio:

[0053] Dihydroxydiphenylmethane glycidyl ether: 15

[0054] 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide): 50

[0055] Hydroxyl-terminated polysiloxane modified bisphenol A glycidyl ether: 12

[0056] Organophosphorus flame retardant (dibutyl phosphate): 10

[0057] 1,6-bis(2,3-epoxypropoxy)hexane: 13

[0058] Additive (polydimethylsiloxane): 0.2

[0059] Component B (i.e., the curing agent portion) is in the following mass ratio:

[0060] IPDA (5-amino-1,3,3-trimethylcyclohexylamine): 83.8

[0061] D-230 (polyetheramine): 15

[0062] DMP-30: 1.2

[0063] The preparation methods for components A and B are the same as in Example 1.

[0064] When using, take component A and component B and mix them evenly in a mass ratio of 100:23.

[0065] Example 3

[0066] 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide): 65

[0067] Hydroxyl-terminated polysiloxane modified bisphenol A glycidyl ether: 19

[0068] Organophosphorus flame retardant (dimethyl phosphate): 6

[0069] 1,4-bis(2,3-epoxypropoxy)butane: 10

[0070] Additive (epoxy-modified silicone oil): 0.2

[0071] Component B (i.e., the curing agent portion) is in the following mass ratio:

[0072] PACM (4,4-diaminodicyclohexylmethane): 87.8

[0073] D-400 (Polyetheramine): 11

[0074] N,N-dimethylbenzylamine: 1.2

[0075] The preparation methods for components A and B are the same as in Example 1.

[0076] When using, take component A and component B and mix them evenly in a mass ratio of 100:23.

[0077] Example 4

[0078] 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide): 64

[0079] Hydroxyl-terminated polysiloxane modified bisphenol A glycidyl ether: 16

[0080] Organophosphorus flame retardant (dimethyl phosphate): 10

[0081] 1,4-bis(2,3-epoxypropoxy)butane: 10

[0082] Additive (epoxy-modified silicone oil): 0.5

[0083] Component B (i.e., the curing agent portion) is in the following mass ratio:

[0084] IPDA (5-amino-1,3,3-trimethylcyclohexylamine): 88.8

[0085] D-2000 (Polyetheramine): 10

[0086] N,N-dimethylbenzylamine: 1.2

[0087] The preparation methods for components A and B are the same as in Example 1.

[0088] When using, take component A and component B and mix them evenly in a mass ratio of 100:22.

[0089] Comparative Example 1

[0090] Component A (i.e., the epoxy resin portion) is in the following mass ratio:

[0091] Dihydroxydiphenylmethane glycidyl ether 15

[0092] 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide): 50

[0093] Hydroxyl-terminated polysiloxane modified bisphenol A glycidyl ether: 12

[0094] Organophosphorus flame retardant: 18

[0095] 1,4-Bis(2,3-epoxypropoxy)butane:5

[0096] Additive (epoxy-modified silicone oil): 0.2

[0097] Component B (i.e., the curing agent portion) is in the following mass ratio:

[0098] IPDA (5-amino-1,3,3-trimethylcyclohexylamine): 95

[0099] D-2000 (Polyetheramine): 3.5

[0100] N,N-dimethylbenzylamine: 1.5

[0101] The preparation methods for components A and B are the same as in Example 1.

[0102] When using, take component A and component B and mix them evenly in a mass ratio of 100:20.

[0103] Performance tests were conducted on the above embodiments in accordance with relevant national and industry standards, and the test results are shown in Table 1 below. In the table,

[0104] 1. Mixed viscosity: Refer to GB / T 22314-2008

[0105] 2. Operable time test: Refer to standard GB / T7123.1~7123.2-2002

[0106] 3. Glass transition temperature test: Refer to standard GB / T 19466.2-2004

[0107] 4. Tensile properties test of casting: Refer to standard GB / T 2567-2008.

[0108] Table 1 Performance test results of the examples and comparative examples

[0109]

[0110]

[0111] (Note: The curing conditions for the composition are 60℃ / 1h + 95℃ / 5h)

[0112] In addition to the basic raw materials, the resin and curing agent components in the above embodiments can also be supplemented with other additives that do not affect their overall performance, such as pigments and fillers.

Claims

1. A halogen-free flame-retardant epoxy resin system composition, characterized in that: The epoxy resin system composition comprises an epoxy resin portion and a curing agent portion. The epoxy resin portion consists of dihydroxydiphenylmethane glycidyl ether, 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bisepoxyethylene, hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether, organophosphorus flame retardant, epoxy-based reactive diluent, and additives. The curing agent portion consists of alicyclic amine curing agent, polyether amine curing agent, and accelerator.

2. The halogen-free flame-retardant epoxy resin system composition according to claim 1, characterized in that: The epoxy resin portion, by mass ratio, is: dihydroxydiphenylmethane glycidyl ether: 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide): hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether: organophosphorus flame retardant: epoxy-based reactive diluent: additives = 0-30: 20-60: 12-25: 5-15: 5-15: 0.2-1.

3. The halogen-free flame-retardant epoxy resin system composition according to claim 2, characterized in that: The epoxy resin portion, by mass ratio, is: dihydroxydiphenylmethane glycidyl ether: 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide): hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether: organophosphorus flame retardant: epoxy-based reactive diluent: additives = 15-30: 35-50: 12-20: 8-10: 10-13: 0.2-1.

4. The halogen-free flame-retardant epoxy resin system composition according to claim 1 or 2, characterized in that: The dihydroxydiphenylmethane glycidyl ether has an epoxy equivalent of 160-180 g / eq and a viscosity of 2000-5000 mPa·s. The epoxy equivalent of the 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide) is 170-180 g / eq.

5. A halogen-free flame-retardant epoxy resin system composition according to claim 1 or 2, characterized in that: The hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether is prepared by reacting hydroxyl-terminated polyphenylpropylsiloxane with bisphenol A type epoxy resin. The organophosphorus flame retardant resin is selected from at least one of aliphatic phosphate esters, phosphate ester compounds, condensed phosphate esters, and phosphonates. The epoxy-based reactive diluent is selected from at least one of 1,4-bis(2,3-epoxypropoxy)butane and 1,6-bis(2,3-epoxypropoxy)hexane; The additives are selected from defoamers and / or release agents. The defoamers are selected from at least one of emulsified silicone oil, high carbon alcohol fatty acid ester complex, polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropylene alcohol amine ether, polyoxypropylene glycerol ether, polyoxypropylene polyoxyethylene glycerol ether, and polydimethylsiloxane. The release agents are selected from at least one of epoxy-modified silicone oil, polyvinyl alcohol, and polyisobutylene.

6. The halogen-free flame-retardant epoxy resin system composition according to claim 1, characterized in that: The curing agent portion, by mass ratio, is cycloaliphatic amine curing agent: polyether amine curing agent: accelerator = 75-90: 10-25: 1-2.

7. A halogen-free flame-retardant epoxy resin system composition according to claim 1 or 6, characterized in that: The alicyclic amine curing agent is selected from at least one of 5-amino-1,3,3-trimethylcyclohexylmethylamine and 4,4'-diaminodicyclohexylmethane; The polyetheramine curing agent is selected from polyether diamine or polyether triamine, with a molecular weight between 200 and 5000. The accelerator is selected from at least one of N,N-dimethylbenzylamine and DMP-30.

8. The halogen-free flame-retardant epoxy resin system composition according to claim 1, characterized in that: The preparation process of the epoxy resin part is as follows: hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether, dihydroxydiphenylmethane glycidyl ether, 2,2'-[(1-methylethylidene)bis(4,1-phenyleneformaldehyde)]bis(ethylene oxide), hydroxyl-terminated polysiloxane-modified bisphenol A glycidyl ether, organophosphorus flame retardant, epoxy-based reactive diluent, and additives are heated to 50-70℃ and stirred for 60-90 minutes, then cooled to 40-50℃ and discharged to obtain the final product; The preparation process of the curing agent is as follows: alicyclic amine curing agent, polyether amine curing agent and accelerator are added into the reaction vessel in proportion, heated to 40-60℃ and stirred for 50-70 minutes, and then cooled to 35-45℃ to obtain the curing agent.

9. The halogen-free flame-retardant epoxy resin system composition according to claim 1, characterized in that: In the epoxy resin system composition, the mass ratio of the epoxy resin portion to the curing agent portion is 100:15-25; The epoxy resin system composition is obtained by mixing the epoxy resin portion and the curing agent portion, and then curing it. The curing conditions are: first, heat preservation at 60-70℃ for 1 hour, and then heat preservation at 90-100℃ for 5-6 hours.

10. The application of the halogen-free flame-retardant epoxy resin system composition according to any one of claims 1-9, characterized in that: The halogen-free flame-retardant epoxy resin system composition is used to prepare fiber epoxy resin composite materials.

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