CN113943415B - Tough flame-retardant epoxy resin and preparation method and use method thereof - Google Patents
Tough flame-retardant epoxy resin and preparation method and use method thereof Download PDFInfo
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- CN113943415B CN113943415B CN202111439430.XA CN202111439430A CN113943415B CN 113943415 B CN113943415 B CN 113943415B CN 202111439430 A CN202111439430 A CN 202111439430A CN 113943415 B CN113943415 B CN 113943415B
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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
- C08G59/14—Polycondensates modified by chemical after-treatment
- C08G59/1433—Polycondensates modified by chemical after-treatment with organic low-molecular-weight compounds
- C08G59/1488—Polycondensates modified by chemical after-treatment with organic low-molecular-weight compounds containing phosphorus
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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
- C08G59/50—Amines
- C08G59/5026—Amines cycloaliphatic
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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
- C08G59/50—Amines
- C08G59/5033—Amines aromatic
Abstract
The invention discloses a tough flame-retardant epoxy resin, a preparation method and a use method thereof, and relates to the technical field of epoxy resin modification. The tough flame-retardant epoxy resin is obtained by reacting bisphenol F epoxy resin with ODOPB and PTMS, and comprises the following steps: 1) adding ODOPB into bisphenol F epoxy resin, and continuously stirring and reacting for 1-2 h at 160-180 ℃ in a nitrogen atmosphere to obtain uniform light yellow liquid; 2) and (3) after the reaction system in the step 1) is cooled to room temperature, adding PTMS and a proper amount of dibutyltin dilaurate serving as a catalyst, heating to 80-90 ℃, and reacting for 1.5-2 h to obtain the tough flame-retardant epoxy resin. The flame retardant epoxy resin with toughness has the advantages of obviously improved flame retardance, toughness and strength, capability of inhibiting smoke and reducing harmful gas, simple raw materials, simple preparation process and wide application prospect.
Description
Technical Field
The invention relates to the technical field of epoxy resin modification, in particular to tough flame-retardant epoxy resin and a preparation method and a use method thereof.
Background
Epoxy resins are one of the most widely used thermosetting resins, and because of their excellent mechanical properties, chemical resistance and low shrinkage, cured products thereof are widely used as base materials for aircraft structural parts, bases for electronic parts, and the like. However, the cured epoxy resin has high crosslinking density, high brittleness and poor impact resistance, and like other high polymer materials, the epoxy resin is easy to burn, which limits the application of the epoxy resin in the high-tech field to a certain extent. However, in order to enhance the flame retardancy, the mechanical properties of the epoxy resin are often damaged, and the use value of the epoxy resin is greatly reduced, so that it is necessary to find a method for simultaneously improving the flame retardancy and the mechanical properties of the epoxy resin.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a tough flame-retardant epoxy resin, and a preparation method and a use method thereof. The flame retardant epoxy resin with toughness has the advantages of obviously improved flame retardance, toughness and strength, capability of inhibiting smoke and reducing harmful gas, simple raw materials, simple preparation process and wide application prospect.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the tough flame-retardant epoxy resin is provided, and the structural formula is as follows:
according to the scheme, the tough flame-retardant epoxy resin is obtained by reacting bisphenol F epoxy resin with 10- (2, 5-dihydroxyphenyl) -10-hydrogen-9-oxa-10-phosphaphenanthrene-10-oxide and phenyltrimethoxysilane.
Preferably, the epoxy value of the bisphenol F epoxy resin is 0.58 to 0.6.
Preferably, the mass ratio of the bisphenol F epoxy resin to the 10- (2, 5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide to the phenyltrimethoxysilane is 100: 7-8: 7-8.
The preparation method of the tough flame-retardant epoxy resin comprises the following steps:
1) adding 10- (2, 5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide (ODOPB) into bisphenol F epoxy resin, and continuously stirring and reacting for 1-2 hours at 160-180 ℃ in a nitrogen atmosphere to obtain uniform light yellow liquid;
2) and (2) when the reaction system in the step 1) is cooled to room temperature, adding phenyl trimethoxy silane (PTMS) and a proper amount of dibutyltin dilaurate as catalysts, heating to 80-90 ℃, and reacting for 1.5-2 h to obtain the tough flame-retardant epoxy resin.
According to the scheme, the mass ratio of the bisphenol F epoxy resin to the ODOPB is 100: 7 to 8.
According to the scheme, the mass ratio of the bisphenol F epoxy resin to the PTMS is 100: 7-8.
According to the scheme, the using amount of the dibutyltin dilaurate catalyst is 0.5-1% of the mass of the PTMS.
According to the scheme, the epoxy value of the bisphenol F epoxy resin is 0.58-0.6.
The application method of the tough flame-retardant epoxy resin comprises the following steps:
mixing diethyl toluenediamine (DETDA) and isophorone diamine (IPDA) to serve as a curing agent, adding the curing agent into the tough flame-retardant epoxy resin, mechanically stirring uniformly, and defoaming for 10-15min in vacuum; pouring the mixture into a mold, and curing at 80-90 ℃/2-3h, 110-120 ℃/2-3h and 140-150 ℃/5-6 h; after that, it was naturally cooled to room temperature to prevent cracking.
According to the scheme, the mass ratio of the bisphenol F epoxy resin to the curing agent in the tough flame-retardant epoxy resin is 100: 24 to 25.
The invention has the following beneficial effects:
1. the invention provides a tough flame-retardant epoxy resin, which is prepared by carrying out synergistic modification on bisphenol F epoxy resin through a phosphorus source ODOPB and a silicon source PTMS: on the one hand, the phosphorus source contains benzene ring and phosphaphenanthrene group, can be decomposed at high temperature to generate polymetaphosphate to promote the formation of a compact carbon layer, and can generate PO2When the chain reaction is interrupted by free radicals, the flame retardant has excellent flame retardant property; the silicon source contains benzene rings, and is decomposed at high temperature to form a smooth and compact shell layer to cover the surface of the resin, so that the effect of isolating oxygen and heat is achieved, and the flame retardance is further enhanced; on the other hand, the phosphorus source is grafted on the main chain of the epoxy resin, so that the thermal stability of the epoxy resin is improved, the silicon source is grafted on the side chain of the epoxy resin, 3 reaction groups can form a hyperbranched structure, so that the toughness of the epoxy resin is improved, and the phosphorus source and silane are grafted at different positions of the epoxy resin, are not interfered and are matched with each other; through the synergistic modification of phosphorus and silicon, the flame retardance and the toughness of the epoxy resin are obviously improved, the generation of smoke is inhibited while the flame retardance is realized, and the generation of harmful gases is reduced.
2. The invention provides a preparation method of tough flame-retardant epoxy resin, which has the advantages of simple preparation method, mild conditions, low cost, little environmental pollution in the synthesis process and wide industrial application prospect.
Drawings
FIG. 1 is an infrared spectrum of a phosphorus/silicon synergistically modified tough flame-retardant epoxy resin prepared in example 1 of the present invention.
FIG. 2 is a digital photograph of a pure epoxy resin synthesized in comparative example 1 of the present invention after EP cone calorimetry.
FIG. 3 is a digital photograph of the modified epoxy resin synthesized in example 1 of the present invention after EP-P/Si cone calorimetry test.
FIG. 4 is a scanning electron microscope image of a cross section of a pure epoxy resin synthesized in comparative example 1 according to the present invention after EP tensile test.
FIG. 5 is a scanning electron microscope image of a cross section of the modified epoxy resin synthesized in example 1 of the present invention after EP-P/Si tensile test.
Detailed Description
The present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
Comparative example 1
To 100g of bisphenol F epoxy resin (epoxy value about 0.59) was added 24g of a curing agent which was a mixture of DETDA and IPDA in a mass ratio of 5: 1. And defoaming for 10min under vacuum after mechanically stirring uniformly, finally pouring the mixture into a mold, solidifying at 90 ℃/2h, 120 ℃/2h and 150 ℃/5h, and naturally cooling to room temperature to prevent cracking, wherein the sample is recorded as EP.
Example 1
The preparation method of the tough flame-retardant epoxy resin comprises the following steps:
step 1, adding 7.9g of ODOPB into 100g of bisphenol F epoxy resin (the epoxy value is about 0.59), and continuously stirring and reacting for 1.5h at 180 ℃ in a nitrogen atmosphere to obtain uniform light yellow liquid;
and 2, after the epoxy resin is cooled to room temperature, adding 7.6g of PTMS and 0.0076g of dibutyltin dilaurate serving as catalysts, heating to 90 ℃, and reacting for 2 hours at the temperature to obtain the tough flame-retardant epoxy resin.
The specific equation is as follows:
diethyl toluenediamine (DETDA) and isophorone diamine (IPDA) are mixed according to the mass ratio of 5:1 to be used as a curing agent, 24g of curing agent is added into the prepared tough flame-retardant epoxy resin, the mechanical stirring is carried out uniformly, and the defoaming is carried out for 10min under vacuum. Pouring the mixture into a mould, solidifying at 90 ℃/2h, 120 ℃/2h and 150 ℃/5h, and naturally cooling to room temperature, wherein the sample is marked as EP-P/Si.
FIG. 1 is an infrared spectrum of 1299cm of a tough flame-retardant epoxy resin synergistically modified with phosphorus and silicon obtained in example 1 of the present invention-1Is P ═ O stretching vibration peak, 1585cm-1Is a characteristic peak of P-Ph, 1129cm-1And 1085cm-1The absorption peak is Si-O-C. This fully demonstrates the successful reaction of bisphenol F epoxy with ODOPB and PTMS to give a new phosphorus containing silicon containing resin EP-P/Si.
FIGS. 2 and 3 are digital photographs of the pure epoxy resin EP obtained in comparative example 1 and the EP-P/Si cone calorimetry obtained in example 1, respectively, according to the present invention. It can be seen that the pure epoxy resin EP has been almost completely burned off with only a very small carbon residue remaining. While the EP-P/Si carbon residue is fluffy and is beneficial to hindering combustion.
FIGS. 4 and 5 are scanning electron micrographs of sections after tensile testing of the pure epoxy resin EP obtained in comparative example 1 and the EP-P/Si obtained in example 1, respectively, according to the invention. It can be seen that the cross section of the pure epoxy EP is smooth and shows a pronounced brittle fracture. The EP-P/Si section is rough, and a plurality of ridge-shaped structures are distributed on the section, so that the fracture is ductile and the toughness is improved.
Table 1 shows the Limiting Oxygen Index (LOI) of EP and EP-P/Si, and it can be seen that the LOI is greatly improved after phosphorus/silicon modification, indicating that the flame retardancy of the epoxy resin is improved.
TABLE 1 Limiting Oxygen Index (LOI) of EP and EP-P/Si
Table 2 summarizes the data for EP and EP-P/Si cone calorimetry, that the ignition time (TTI) for EP is 11s, while the TTI for EP-P/Si increases to 43s, indicating that a longer time is required to ignite the epoxy after the phosphorus/silicon co-modification. Furthermore, the Peak Heat Release Rate (PHRR) was from 1683.9kW/m of EP through a synergistic phosphorus/silicon interaction2Reduced to 1077.5kW/m of EP-P/Si2And the reduction is 36 percent. Likewise, the total exotherm (THR) is 84.0MJ/m from EP2Reduced to 67.6MJ/m of EP-P/Si2Is flat and flatThe average effective combustion heat (av-EHC) is also 23.4MJ/m2The temperature is reduced to 20.76MJ/m2. These parameters all indicate a significant improvement in the flame retardancy of the epoxy resin. Furthermore, the total smoke release (TSP) was also reduced by 7.2% compared to EP, indicating that the phosphorus/silicon synergy may also inhibit smoke release.
TABLE 2 EP and EP-P/Si Cone calorimetry data
Table 3 shows the mechanical property data of EP and EP-P/Si, and it can be found that the tensile strength and modulus of EP-P/Si are respectively 30.0% and 10.7% higher than that of EP, the elongation at break is increased by 72.7%, the bending strength and modulus are respectively 6.9% and 3.4% higher than that of EP, and the impact strength is 371.8% higher than that of EP. This indicates that the phosphorus/silicon synergistic effect can also improve the toughness of the epoxy resin.
TABLE 3 mechanical Properties of EP and EP-P/Si
It is apparent that the above embodiments are only examples for clearly illustrating and do not limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications are therefore intended to be included within the scope of the invention as claimed.
Claims (10)
1. The tough flame-retardant epoxy resin is characterized by having a structural formula as follows:
2. the tough flame-retardant epoxy resin according to claim 1, wherein the tough flame-retardant epoxy resin is obtained by reacting bisphenol F epoxy resin with 10- (2, 5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide and phenyltrimethoxysilane.
3. The tough flame retardant epoxy resin of claim 2, wherein the epoxy value of the bisphenol F epoxy resin is 0.58 to 0.6.
4. A method for preparing the tough flame-retardant epoxy resin according to any one of claims 1 to 3, which comprises the following steps:
1) adding 10- (2, 5-dihydroxyphenyl) -10-hydrogen-9-oxa-10-phosphaphenanthrene-10-oxide into bisphenol F epoxy resin, and continuously stirring and reacting for 1-2 hours at 160-180 ℃ in a nitrogen atmosphere to obtain uniform light yellow liquid;
2) and (2) after the reaction system in the step 1) is cooled to room temperature, adding phenyl trimethoxy silane and a proper amount of dibutyltin dilaurate serving as a catalyst, heating to 80-90 ℃, and reacting for 1.5-2 h to obtain the tough flame-retardant epoxy resin.
5. The method according to claim 4, wherein the mass ratio of the bisphenol F epoxy resin to the 10- (2, 5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide is 100: 7 to 8.
6. The method according to claim 4, wherein the mass ratio of bisphenol F epoxy resin to phenyltrimethoxysilane is 100: 7 to 8.
7. The preparation method of the epoxy resin composition as claimed in claim 4, wherein the amount of the dibutyltin dilaurate serving as the catalyst is 0.5-1% of the mass of the phenyltrimethoxysilane.
8. The method according to claim 4, wherein the epoxy value of the bisphenol F epoxy resin is 0.58 to 0.6.
9. A method of using the tough flame retardant epoxy resin of any one of claims 1-3, comprising the steps of:
mixing diethyl toluenediamine and isophorone diamine to be used as a curing agent, adding the curing agent into the tough flame-retardant epoxy resin according to any one of claims 1-3, mechanically stirring uniformly, and defoaming for 10-15min in vacuum; pouring the mixture into a mold, and curing at 80-90 ℃/2-3h, 110-120 ℃/2-3h and 140-150 ℃/5-6 h; after that, it is naturally cooled to room temperature to prevent cracking.
10. The use method of claim 9, wherein the mass ratio of the bisphenol F epoxy resin to the curing agent in the tough flame-retardant epoxy resin is 100: 24-25.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010184960A (en) * | 2009-02-10 | 2010-08-26 | Asahi Kasei Chemicals Corp | Modified resin composition, cured product thereof, and sealant containing the same, and method for producing modified resin composition |
| CN109897503A (en) * | 2019-03-08 | 2019-06-18 | 胡志忠 | A kind of normal temperature cure modifying epoxy resin by organosilicon coating and the preparation method and application thereof |
| CN110591288A (en) * | 2019-09-11 | 2019-12-20 | 西北工业大学 | Hyperbranched silicon-phosphorus synergistic flame retardant modified epoxy resin and preparation method thereof |
| CN113025253A (en) * | 2021-03-17 | 2021-06-25 | 广州市白云化工实业有限公司 | Single-component silane modified polyether sealant and preparation method and application thereof |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010184960A (en) * | 2009-02-10 | 2010-08-26 | Asahi Kasei Chemicals Corp | Modified resin composition, cured product thereof, and sealant containing the same, and method for producing modified resin composition |
| CN109897503A (en) * | 2019-03-08 | 2019-06-18 | 胡志忠 | A kind of normal temperature cure modifying epoxy resin by organosilicon coating and the preparation method and application thereof |
| CN110591288A (en) * | 2019-09-11 | 2019-12-20 | 西北工业大学 | Hyperbranched silicon-phosphorus synergistic flame retardant modified epoxy resin and preparation method thereof |
| CN113025253A (en) * | 2021-03-17 | 2021-06-25 | 广州市白云化工实业有限公司 | Single-component silane modified polyether sealant and preparation method and application thereof |
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