CN111574689A - Modified novel epoxy insulating resin matrix and preparation method thereof - Google Patents

Modified novel epoxy insulating resin matrix and preparation method thereof Download PDF

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Publication number
CN111574689A
CN111574689A CN202010285627.1A CN202010285627A CN111574689A CN 111574689 A CN111574689 A CN 111574689A CN 202010285627 A CN202010285627 A CN 202010285627A CN 111574689 A CN111574689 A CN 111574689A
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China
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curing agent
insulating resin
resin matrix
parts
ethanol
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Chinese (zh)
Inventor
马超强
马宏
马奎
张桂苹
马俊
赵梦洋
孙振
李雨含
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Anhui Jinquan Fishing Tool Co ltd
Jieshou Chaoqiang Fishing Tackle Co ltd
Jieshou Ousirun Sports Goods Co ltd
Anhui Wilma Fishing Tools Co ltd
Original Assignee
Anhui Jinquan Fishing Tool Co ltd
Jieshou Chaoqiang Fishing Tackle Co ltd
Jieshou Ousirun Sports Goods Co ltd
Anhui Wilma Fishing Tools Co ltd
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Priority to CN202010285627.1A priority Critical patent/CN111574689A/en
Publication of CN111574689A publication Critical patent/CN111574689A/en
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G59/00—Polycondensates containing more than one epoxy group per molecule; Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups
    • C08G59/18—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing
    • C08G59/40—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing characterised by the curing agents used
    • C08G59/4007—Curing agents not provided for by the groups C08G59/42 - C08G59/66
    • C08G59/4014—Nitrogen containing compounds
    • C08G59/4021—Ureas; Thioureas; Guanidines; Dicyandiamides
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C277/00—Preparation of guanidine or its derivatives, i.e. compounds containing the group, the singly-bound nitrogen atoms not being part of nitro or nitroso groups
    • C07C277/08—Preparation of guanidine or its derivatives, i.e. compounds containing the group, the singly-bound nitrogen atoms not being part of nitro or nitroso groups of substituted guanidines
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G59/00—Polycondensates containing more than one epoxy group per molecule; Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups
    • C08G59/18—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing
    • C08G59/40—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing characterised by the curing agents used
    • C08G59/50—Amines
    • C08G59/504—Amines containing an atom other than nitrogen belonging to the amine group, carbon and hydrogen
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Epoxy Resins (AREA)

Abstract

The invention discloses a modified novel epoxy insulating resin matrix and a preparation method thereof, and the preparation method comprises the following steps of firstly, adding 8.4kg of dicyandiamide and 6.0kg of modifier ethylenediamine into 300kg of 0.8mol/L hydrochloric acid solution, heating to 180 ℃, reacting, decompressing every 1 hour to remove ammonia gas generated by the reaction, reacting for 4 hours, cooling and filtering after the reaction is finished, and drying at 25 ℃ room temperature to obtain a curing agent; then 5kg of curing agent is ultrasonically dissolved in 30kg of ethanol; then, uniformly mixing the ethanol solution containing the curing agent with 80kg of epoxy resin to obtain a mixed system; and finally, drying the mixed system at 25 ℃ and under-0.1 MPa under reduced pressure until no ethanol is evaporated to obtain the epoxy insulating resin matrix.

Description

Modified novel epoxy insulating resin matrix and preparation method thereof
Technical Field
The invention relates to the technical field of epoxy insulating resin matrixes, and particularly belongs to a modified novel epoxy insulating resin matrix and a preparation method thereof.
Background
Currently, in the production of fishing rods, the most used resin matrix is high-temperature cured phenolic resin and medium-temperature cured epoxy resin. The phenolic resin has the advantages of low price and the like, but can only be used for producing lower-grade fishing rods because water and other low molecular products are discharged in the curing process, so that a plurality of micropores and bubbles are generated in the blank and on the surface, and the mechanical property and the appearance of the product are influenced. Epoxy resin does not discharge low molecular products in the curing process, the surface of the product is smooth and compact, and the product has excellent mechanical properties, so that the epoxy resin is generally adopted as matrix resin of a fishing rod in the production of high-grade fishing rods such as carbon fiber fishing rods and mixed fiber fishing rods. However, the existing epoxy resin has the following disadvantages: firstly, epoxy resin is easy to cure at low temperature, so that production raw materials cannot be stored for a long time; second, the initial curing temperature of the epoxy resin is high, which increases the production cost.
Disclosure of Invention
The invention aims to provide a novel modified epoxy insulating resin matrix for fishing gear products and a preparation method thereof, and solves the problems that epoxy resin in the prior art is easy to cure at low temperature and has high initial curing temperature.
In order to solve the problems, the technical scheme adopted by the invention is as follows:
the novel modified epoxy insulating resin matrix comprises a curing agent and epoxy resin.
Preferably, the raw materials comprise 3-8 parts of curing agent and 70-80 parts of epoxy resin.
Preferably, the curing agent is dicyandiamide.
Preferably, the curing agent is modified dicyandiamide, and the modification method of the modified dicyandiamide is as follows: adding 84 parts by weight of dicyandiamide and 60 parts by weight of modifier ethylenediamine into 300 parts by weight of 0.8mol/L hydrochloric acid solution, heating to 180 ℃, and reacting, wherein the reaction equation is as follows:
Figure BDA0002448397390000021
and (3) reducing the pressure every 1 hour to remove ammonia gas generated by the reaction, reacting for 4-12 hours, cooling, filtering and drying at room temperature after the reaction is finished to obtain the curing agent.
The preparation method of the modified novel epoxy insulating resin matrix for the fishing gear product comprises the following steps: firstly, dissolving 3-8 parts of curing agent in 20-30 parts of ethanol by ultrasonic waves; then, uniformly mixing the ethanol solution containing the curing agent with 70-80 parts of epoxy resin to obtain a mixed system; and finally, drying the mixed system at 20-35 ℃ and under the pressure of-0.1 MPa under reduced pressure until no ethanol is evaporated out to obtain the epoxy insulating resin matrix.
Compared with the prior art, the invention has the following implementation effects: the invention adopts hexanediamine to modify dicyandiamide to prepare the curing agent, the terminal amino group is also subjected to deamination polycondensation while the cyano group is subjected to addition reaction, and the molecular weight is gradually increased along with the extension of the reaction time; but the molecular weight is increased, the average polymerization degree is increased, the lattice spacing is increased, and doping and lattice distortion occur; when the polymerization degree is larger, a large number of incomplete crystals exist in the structure, the molecules of the curing agent break the diffusion of crystal lattices into an epoxy resin system, the curing reaction is accelerated, and the curing peak temperature is reduced by 30 ℃; but the curing agent with smaller polymerization degree has more complete crystal lattices, only amino, biguanidino, hexyl and epoxy resin in the curing agent have poorer compatibility, and only when the curing reaction is started and the molecular chain of the curing agent is connected with the epoxy resin chain segment, the amino, biguanidino, hexyl and epoxy resin can start to be compatible and mutually diffuse to further perform the curing reaction, and simultaneously, the initial curing temperature is reduced by 80 ℃ due to the introduction of a strong electron-donating group, but the storage performance at low temperature is improved; the epoxy insulating resin matrix prepared by the invention has good room temperature storage stability and low initial curing temperature.
Drawings
FIG. 1 is an infrared spectrum of hexamethylenediamine, dicyandiamide and the curing agent of examples 2-4.
FIG. 2 is a 1H-NMR spectrum of the curing agent in examples 2 to 4.
FIG. 3 is an XRD diffraction pattern of the curing agents of examples 2-4.
FIG. 4 is a DSC chart of the epoxy insulating resin matrix in examples 1 to 4.
FIG. 5 is a graph showing the relationship between the storage time and the transition rate at room temperature of the epoxy insulating resin matrix in examples 2 to 4.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The epoxy resin used in the invention adopts a product produced by the North Hebei jumping anticorrosive material company Limited, and other raw materials are all industrial pure raw materials.
Example 1
The modified novel epoxy insulating resin matrix for the fishing gear products is prepared by adopting the following method: firstly, dissolving 5kg of dicyandiamide in 30kg of ethanol by ultrasonic waves; then, uniformly mixing the ethanol solution containing the curing agent with 80kg of epoxy resin to obtain a mixed system; and finally, drying the mixed system at 25 ℃ and under the pressure of-0.1 MPa under reduced pressure until no ethanol is evaporated out to obtain the epoxy insulating resin matrix.
Example 2
The modified novel epoxy insulating resin matrix for the fishing gear products is prepared by adopting the following method: firstly, adding 8.4kg of dicyandiamide and 6.0kg of modifier ethylenediamine into 300kg of 0.8mol/L hydrochloric acid solution, heating to 180 ℃, reacting, decompressing every 1 hour to remove ammonia gas generated by the reaction, reacting for 4 hours, cooling to room temperature after the reaction is finished, filtering, and drying at the room temperature of 25 ℃ to obtain a curing agent; then 5kg of curing agent is ultrasonically dissolved in 30kg of ethanol; then, uniformly mixing the ethanol solution containing the curing agent with 80kg of epoxy resin to obtain a mixed system; and finally, drying the mixed system at 25 ℃ and under the pressure of-0.1 MPa under reduced pressure until no ethanol is evaporated out to obtain the epoxy insulating resin matrix.
Example 3
The modified novel epoxy insulating resin matrix for the fishing gear products is prepared by adopting the following method: firstly, adding 8.4kg of dicyandiamide and 6.0kg of modifier ethylenediamine into 300kg of 0.8mol/L hydrochloric acid solution, heating to 180 ℃, reacting, decompressing every 1 hour to remove ammonia gas generated by the reaction, reacting for 8 hours, cooling, filtering and drying at room temperature after the reaction is finished to obtain a curing agent; then 5kg of curing agent is ultrasonically dissolved in 30kg of ethanol; then, uniformly mixing the ethanol solution containing the curing agent with 80kg of epoxy resin to obtain a mixed system; and finally, drying the mixed system at 25 ℃ and under the pressure of-0.1 MPa under reduced pressure until no ethanol is evaporated out to obtain the epoxy insulating resin matrix.
Example 4
The modified novel epoxy insulating resin matrix for the fishing gear products is prepared by adopting the following method: firstly, adding 8.4kg of dicyandiamide and 6.0kg of modifier ethylenediamine into 300kg of 0.8mol/L hydrochloric acid solution, heating to 180 ℃, reacting, decompressing every 1 hour to remove ammonia gas generated by the reaction, reacting for 12 hours, cooling, filtering and drying at room temperature after the reaction is finished to obtain a curing agent; then 5kg of curing agent is ultrasonically dissolved in 30kg of ethanol; then, uniformly mixing the ethanol solution containing the curing agent with 80kg of epoxy resin to obtain a mixed system; and finally, drying the mixed system at 25 ℃ and under the pressure of-0.1 MPa under reduced pressure until no ethanol is evaporated out to obtain the epoxy insulating resin matrix.
The infrared spectra of hexamethylenediamine, dicyandiamide and the curing agent in examples 2-4 were measured by a Fourier infrared spectrometer, as shown in figure 1, and the absorption peaks of nitrile groups in the infrared spectrum of dicyandiamide at 2208 and 2164cm were measured by reaction-1Disappearance, almost identical spectra of curing agents in examples 2 to 4, all appearing at 3350cm-1To the-NH23146cm of-1Absorption at C ═ N-H, 2929 and 2854cm-1Is located at CH2Absorption of (2), 1650cm-1The absorption of C ≡ N indicates that C ≡ N is added during the reaction, and the structures of the curing agents in examples 2-4 are similar. Preparation of the curing agent in examples 2 to 41The H-NMR spectrum is shown in figure 2, the curing agents in the examples 2-4 have only four main hydrogen atoms, and the chemical shifts of the peaks of the curing agents in the examples 2-4 are basically the same, which indicates that the curing agents in the examples 2-4 have the same structural units; integration of proton peaks revealed that the curing agents of examples 2-4 had similar relative area ratios of the three proton peaks a, b, d, but the proton peak area at c was smaller and smaller, where c (2.75-2.95 ppm) is the chemical shift of the amino group at the end of the aliphatic chain, and the proton peak area at c was smaller and smaller, indicating that the number of terminal groups was smaller and the molecular weight was larger and larger, and the polymerization degrees of the curing agents of examples 2-4 were 2, 4, 10, respectively, as calculated from the relative areas, i.e., the curing agents of examples 2-4 were low in molecular weightThe polymer has the amino end group condensation polymerization in deaminization while the cyano group is subjected to addition reaction, and the molecular weight is gradually increased along with the extension of the reaction time.
The curing agents of examples 2 to 4 were tested by using an X-ray diffractometer, and the diffraction patterns are shown in FIG. 3, the positions of the maximum diffraction peaks of the curing agents of examples 2 to 4 were 23.3, 23.1 and 22.6 degrees, respectively, and the intensity of the diffraction peaks was reduced and the peak width was increased, indicating that as the average polymerization degree of the curing agent was increased, the lattice spacing was increased and doping and lattice distortion occurred.
Thermal analysis tests were performed on the epoxy insulating resin matrices in examples 1 to 4 by using a thermal analyzer, wherein the heating rate was 10 ℃/min, as shown in fig. 4, under the same curing conditions, the maximum curing rate temperatures of the modified curing agent and the epoxy resin were 169, 172 and 188 ℃ respectively, the maximum curing rate temperatures of the dicyandiamide and the epoxy resin in example 1 were 203 ℃, and the curing peak temperature of the modified system was reduced by 30 ℃. Meanwhile, the curing initiation temperatures of the curing agents in examples 2 to 4 were estimated to be 106 ℃, 117 ℃ and 128 ℃ respectively by DSC test results and by extrapolation processing, and were reduced by nearly 80 ℃ as compared with a dicyandiamide/epoxy resin curing system (initiation curing temperature of 189 ℃), indicating that the initiation curing temperature was significantly reduced by modification of dicyandiamide by hexamethylenediamine. The epoxy insulating resin matrices of examples 2-4 were stored at 25 ℃ and sampled every 10 days, and subjected to DSC measurement at a temperature rise rate of 10 ℃/min to obtain experimental values of curing heat as a function of time, and the observation time was 100 days, as shown in fig. 5, the results of which are shown in fig. 5, wherein within 100 days of the observation and measurement, both examples 3 and 4 had thickened and almost lost of tack, while example 2 still had good fluidity and adhesion, indicating that the epoxy insulating resin matrices of example 2 had a shelf life of over 100 days when stored at 25 ℃.
In view of the above, the epoxy insulating resin matrix of example 2 is optimized, the curing initiation temperature is reduced by 80 ℃ compared to the epoxy/dicyandiamide system, and the room temperature storage stability of the cured system is good.
Example 5
3kg of the curing agent from example 2 was dissolved in 20kg of ethanol by sonication; then, uniformly mixing the ethanol solution containing the curing agent with 80kg of epoxy resin to obtain a mixed system; and finally, drying the mixed system at 25 ℃ and under the pressure of-0.1 MPa under reduced pressure until no ethanol is evaporated out to obtain the epoxy insulating resin matrix.
Example 6
5kg of the curing agent from example 2 were dissolved in 25kg of ethanol by sonication; then, uniformly mixing the ethanol solution containing the curing agent with 70kg of epoxy resin to obtain a mixed system; and finally, drying the mixed system at 25 ℃ and under the pressure of-0.1 MPa under reduced pressure until no ethanol is evaporated out to obtain the epoxy insulating resin matrix.
Example 7
6kg of the curing agent from example 2 were dissolved in 20kg of ethanol by sonication; then, uniformly mixing the ethanol solution containing the curing agent with 75kg of epoxy resin to obtain a mixed system; and finally, drying the mixed system at 25 ℃ and under the pressure of-0.1 MPa under reduced pressure until no ethanol is evaporated out to obtain the epoxy insulating resin matrix.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (5)

1. The modified novel epoxy insulating resin matrix and the preparation method thereof are characterized in that the raw materials comprise a curing agent and epoxy resin.
2. The modified novel epoxy insulating resin matrix and the preparation method thereof as claimed in claim 1, wherein the raw materials comprise 3-8 parts of curing agent and 70-80 parts of epoxy resin.
3. The modified novel epoxy insulating resin matrix and the preparation method thereof according to claim 1 or 2, characterized in that: the curing agent is dicyandiamide.
4. The modified novel epoxy insulating resin matrix and the preparation method thereof according to claim 1 or 2, characterized in that the curing agent is modified dicyandiamide, and the modification method of the modified dicyandiamide is as follows: adding 84 parts by weight of dicyandiamide and 60 parts by weight of modifier ethylenediamine into 300 parts of 0.8mol/L hydrochloric acid solution, heating to 180 ℃, reacting, decompressing every 1 hour to remove ammonia gas generated by the reaction, reacting for 4-12 hours, cooling, filtering and drying at room temperature after the reaction is finished to obtain the curing agent.
5. The method for preparing any of the modified novel epoxy insulating resin matrices and the methods for preparing the same according to claims 1-4, characterized by comprising the following steps: firstly, dissolving 3-8 parts of curing agent in 20-30 parts of ethanol by ultrasonic waves; then, uniformly mixing the ethanol solution containing the curing agent with 70-80 parts of epoxy resin to obtain a mixed system; and finally, drying the mixed system at 20-35 ℃ and under the pressure of-0.1 MPa under reduced pressure until no ethanol is evaporated out to obtain the epoxy insulating resin matrix.
CN202010285627.1A 2020-04-13 2020-04-13 Modified novel epoxy insulating resin matrix and preparation method thereof Pending CN111574689A (en)

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