CN108586739B - Homogeneous bismaleimide triazine resin containing cyano and phenolphthalein side group and preparation method thereof - Google Patents
Homogeneous bismaleimide triazine resin containing cyano and phenolphthalein side group and preparation method thereof Download PDFInfo
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- CN108586739B CN108586739B CN201810466375.5A CN201810466375A CN108586739B CN 108586739 B CN108586739 B CN 108586739B CN 201810466375 A CN201810466375 A CN 201810466375A CN 108586739 B CN108586739 B CN 108586739B
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- 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
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
- C08G73/0622—Polycondensates containing six-membered rings, not condensed with other rings, with nitrogen atoms as the only ring hetero atoms
- C08G73/0638—Polycondensates containing six-membered rings, not condensed with other rings, with nitrogen atoms as the only ring hetero atoms with at least three nitrogen atoms in the ring
- C08G73/0644—Poly(1,3,5)triazines
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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
- 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
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
- C08G73/0622—Polycondensates containing six-membered rings, not condensed with other rings, with nitrogen atoms as the only ring hetero atoms
- C08G73/0638—Polycondensates containing six-membered rings, not condensed with other rings, with nitrogen atoms as the only ring hetero atoms with at least three nitrogen atoms in the ring
- C08G73/065—Preparatory processes
Abstract
The invention belongs to the technical field of high-performance high polymer materials, and relates to homogeneous phase bismaleimide triazine resin (BT resin for short) containing cyano and phenolphthalein side groups and a preparation method thereof. Compared with a commercialized heterogeneous BT resin system, the BT resin of the homogeneous system containing the cyano-group and the phenolphthalein side group, which is synthesized by the invention, has the advantages of improved glass transition temperature, bending strength and impact strength, good processing manufacturability and excellent comprehensive performance. Can be used as a novel high-performance resin matrix and widely applied to the national defense and industrial fields of aerospace, electronics, electricity and the like.
Description
Technical Field
The invention belongs to the technical field of high-performance high polymer materials, and relates to a homogeneous phase bismaleimide triazine resin containing cyano and phenolphthalein side groups and a preparation method thereof.
Background
Bismaleimide triazine resin (BT resin for short) is a thermosetting resin with excellent dielectric property, heat resistance and lower moisture absorption rate. Nowadays, epoxy resin is gradually replaced, and the epoxy resin occupies a leading position in the microelectronic industry such as circuit boards. However, the conventional BT resin processing must use a high boiling point solvent harmful to human body and environment to dissolve the monomers and reduce the viscosity of the mixture. Moreover, the toughness of the cured product of the BT resin is poor, the cured system is a two-phase system, and has two glass transition temperatures, and the lower one severely limits the application thereof. Therefore, the homogeneous BT resin system with excellent processing performance, high toughness and high glass transition temperature is obtained through modification, which is very important.
Two phenol ring planes in the phenolphthalein bisphenol monomer are twisted and form a plane included angle which is approximately vertical to the side group of the Cardo ring, and the structure is introduced into the BT resin to obtain a resin system with excellent mechanical property and thermal property. B.F. Zang et al in [ Polymer (2009),50:817-824 ] reported a synthesis method of phenolphthalein-containing cyanate ester, and further obtained a BT resin excellent in mechanical properties and glass transition temperature. G.L.Wu et al [ J.Polym.Res (2014),21:615-623 ] also disclose a preparation method of cyanate ester and BT resin containing phenolphthalein side groups, and the toughness of the obtained resin system is obviously improved, but the glass transition temperature is lower.
The cyano-group active functional group has strong electron-withdrawing effect, and the existence of the cyano-group active functional group can enhance intermolecular force of the polymer and endow the material with excellent mechanical property and heat resistance. CN104629052A discloses only the preparation method of bismaleimide monomer containing cyano group and phenolphthalein structure, but it is not used to prepare high performance homogeneous BT resin.
Diallyl bisphenol A (DABPA) is an excellent modifier of the BT resin, and simultaneously is used as a catalyst of cyanate ester, so that the cyanate ester can be promoted to carry out triazinization reaction at a lower temperature, and the processability of a resin system is improved. W.X.Wang et al in (engineering plastics application (2011),39(3): 27-30) report modification research of DABPA on commercial BT resin, and obtain a modified BT resin system with excellent mechanical property and dielectric property, but the influence of the content of DABPA on the structure and the performance of the BT resin system is not deeply researched. Modification of bismaletriazine-BT resin system and composite material thereof research by w.x.wang et al [ D ]. shanghai: the influence of DABPA on the structure and performance of a BT resin system containing commercial diphenylmethane Bismaleimide (BDM) and bisphenol A cyanate ester (BADCy) is researched by the university of east China science and engineering, 2010, and the influence of DABPA on the structure and performance of the BT resin system is found out.
Disclosure of Invention
The invention aims to overcome the defects of the traditional BT resin and provides a preparation method of a homogeneous BT resin system containing cyano and phenolphthalein side groups, wherein the resin system has higher glass transition temperature, and meanwhile, the molecular chain of the system is prolonged, and the crosslinking density is reduced, so that the resin system has better toughness and processing manufacturability. In addition, the presence of cyano groups and rigid phenolphthalein side groups may also impart good heat resistance properties to the resin system. In conclusion, the novel BT resin system with excellent comprehensive performances such as mechanical property, thermal property and the like is obtained.
In order to achieve the purpose, the technical scheme of the invention is as follows:
the homogeneous bismaleimide triazine resin containing cyano and phenolphthalein side groups is prepared by mixing bismaleimide monomers (MCBMI) containing cyano and phenolphthalein side groups with bisphenol A cyanate (BADCy), and has the following system structure:
the preparation method of the homogeneous bismaleimide triazine resin containing the cyano group and the phenolphthalein side group comprises the following steps:
heating and melting bisphenol A cyanate ester (BADCy), adding bismaleimide resin (MCBMI) containing cyano and phenolphthalein side groups, stirring and reacting at 120-140 ℃ to obtain uniform transparent liquid, placing the obtained mixed system in a vacuum oven at the same temperature for defoaming for 40-60 min, curing according to the curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the MCBMI/BADCy homogeneous resin system. The weight ratio of the bismaleimide resin MCBMI to the bisphenol A cyanate BADCy is 1: 2-1: 5.
The homogeneous phase bismaleimide triazine resin containing cyano and phenolphthalein side groups is prepared by mixing bismaleimide monomers (MCBMI) containing cyano and phenolphthalein side groups, bisphenol A type cyanate ester (BADCy) and diallyl bisphenol A, and the structure of the homogeneous phase bismaleimide triazine resin system is shown as follows;
the preparation method of the homogeneous bismaleimide triazine resin containing the cyano group and the phenolphthalein side group comprises the following steps:
mixing bisphenol A cyanate ester (BADCy) and diallyl bisphenol A (DABPA), heating and melting at 120-140 ℃, uniformly stirring, adding bismaleimide resin (MCBMI) containing cyano and phenolphthalein side groups, taking diallyl bisphenol A as a modifier and a catalyst, stirring at the same temperature to obtain a uniform and transparent system, defoaming the obtained mixed system in a vacuum oven at the same temperature for 40-60 min, curing according to a curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the MCBMI/BADCy/DABPA homogeneous resin system. The mass ratio of the total mass of MCBMI and DABPA to BADCy is 1: 2-1: 5, and the mass ratio of DABPA to MCBMI is 1: 0.8-1.2.
The invention has the beneficial effects that: compared with a commercial heterogeneous BT resin system, the synthesized BT resin containing a homogeneous system of cyano-group and phenolphthalein side groups has the advantages that the glass transition temperature can be increased by 21-36 ℃, the bending strength can be increased by 14.2-26.9%, the bending modulus can be increased by 4.1-9.4%, and the impact strength can be increased by 49.5-133.9%. In conclusion, the resin system has excellent comprehensive properties such as thermal property, mechanical property and the like.
Drawings
FIG. 1 is an IR trace of a control commercial BDM/BADCy resin system;
FIG. 2 is an IR trace of the MCBMI/BADCy resin system of example 1;
FIG. 3 is an IR trace of the BDM/BADCy/DABPA resin system of example 3;
FIG. 4 is a DMA plot of the homogeneous BT resin system prepared, with the peak temperature of tan delta being the glass transition temperature of the system;
FIG. 5 is a graph of the flexural properties of the homogeneous BT resin systems prepared;
fig. 6 is a graph of impact properties of the homogeneous BT resin systems prepared.
Detailed Description
The invention will now be further elucidated with reference to an example.
Example 1
Heating and melting 20g of bisphenol A cyanate ester (BADCy) at 130 ℃, adding 5g of bismaleimide monomer (MCBMI) containing cyano and phenolphthalein groups, keeping the temperature unchanged, stirring to obtain a reddish-brown uniform and transparent liquid, then placing the liquid in a vacuum oven at 130 ℃ for defoaming for 50min, curing according to the curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the BT resin (MCBMI/BADCy resin system) with a homogeneous system.
Control group
Heating and melting 20g of bisphenol A type cyanate ester (BADCy) at 130 ℃, adding 5g of diphenylmethane bismaleimide monomer (BDM), keeping the temperature unchanged, stirring to obtain a reddish brown uniform transparent liquid, then defoaming for 50min in a vacuum oven at 130 ℃, curing according to a curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the BT resin (BDM/BADCy resin system) with a phase separation system.
The bismaleimide monomer (MCBMI) in example 1 and the bisphenol a cyanate (BADCy) undergo copolymerization reaction first, and the excessive bisphenol a cyanate (BADCy) undergoes self polymerization reaction to form triazine ring, so as to form a uniform interpenetrating network (IPN) structure, and the introduction of cyano group can enhance intermolecular force, and the introduction of phenolphthalein can enhance the rigidity of the molecular structure. And bisphenol A cyanate ester (BADCy) and diphenylmethane bismaleimide monomer (BDM) in the comparison group are respectively homopolymerized to form a two-phase structure, and the acting force between the two phases is weaker. Thus, the MCBMI/BADCy resin system has only one glass transition temperature (289 ℃ C.) and the BDM/BADCy resin system has two glass transition temperatures (253 ℃ C., 289 ℃ C.). Compared with a control group BDM/BADCy resin system, the MCBMI/BADCy resin system has the advantages that the bending strength is improved by 14.2 percent and reaches 89.3 MPa, the bending modulus is improved by 9.4 percent and reaches 3.5GPa, and the impact strength is improved by 49.6 percent and reaches 5.34kJ/m2。
Example 2
20g of bisphenol A cyanate (BADCy) and 0.97g of diallyl bisphenol A (DABPA) were melted together by heating at 130 ℃. 4.03g of MCBMI was added thereto, and the mixture was stirred at the same temperature until the system became reddish brown, uniform and transparent. And (3) placing the obtained mixture in a vacuum oven at 130 ℃ for defoaming for 50min, curing according to a curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the DABPA modified homogeneous MDB0.8 resin system.
Example 3
20g of bisphenol A cyanate ester (BADCy) and 1.15g of diallylbisphenol A were melted together by heating at 130 ℃. 3.85g of MCBMI was added and stirred at the same temperature until the system was reddish brown, uniform and transparent. And (3) placing the obtained mixture in a vacuum oven at 130 ℃ for defoaming for 50min, curing according to a curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the DABPA modified homogeneous MDB1.0 resin system.
Example 4
20g of bisphenol A cyanate ester (BADCy) and 1.32g of diallylbisphenol A were melted together by heating at 130 ℃. 3.68g of MCBMI was added and stirred at the same temperature until the system was reddish brown, uniform and transparent. And (3) placing the obtained mixture in a vacuum oven at 130 ℃ for defoaming for 50min, curing according to a curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the DABPA modified homogeneous MDB1.2 resin system.
In example 4, diallyl bisphenol a (DABPA) was further introduced, after the addition, DABPA was copolymerized with bismaleimide monomer (MCBMI), bisphenol a type cyanate ester (BADCy) was homopolymerized, and the two network structures formed were entangled with each other to form a homogeneous system. Compared with a BDM/BADCy resin system of a comparison group, the MDB1.2 resin system only has one glass transition temperature, and has the use temperature 24 ℃ higher than that of the BDM/BADCy resin system, the bending strength is improved by 21.0 percent to 99.2MPa, the bending modulus is improved by 4.1 percent to 3.3GPa, and the impact strength is improved by 133.9 percent to 8.35kJ/m2.
Example 5
Heating and melting 20g of bisphenol A cyanate ester (BADCy) at 120 ℃, adding 4g of bismaleimide monomer (MCBMI) containing cyano and phenolphthalein groups, keeping the temperature unchanged, stirring to obtain a reddish-brown uniform and transparent liquid, then placing the liquid in a vacuum oven at 120 ℃ for defoaming for 50min, curing according to the curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the BT resin with a homogeneous system.
Example 6
20g of bisphenol A cyanate (BADCy) and 1.93g of diallylbisphenol A were melted together by heating at 140 ℃. 8.07g of MCBMI was added and stirred at the same temperature until the system was reddish brown, uniform and transparent. And (3) placing the obtained mixture in a vacuum oven at 140 ℃ for defoaming for 60min, curing according to a curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the DABPA modified homogeneous MDB resin system.
Example 7
20g of bisphenol A cyanate (BADCy) and 1.29g of diallylbisphenol A were melted together by heating at 140 ℃. 5.38g of MCBMI was added thereto, and the mixture was stirred at the same temperature until the system became reddish brown, uniform and transparent. And (3) placing the obtained mixture in a vacuum oven at 140 ℃ for defoaming for 50min, curing according to a curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the DABPA modified homogeneous MDB resin system.
The above-mentioned embodiments only express the embodiments of the present invention, but not should be understood as the limitation of the scope of the invention patent, it should be noted that, for those skilled in the art, many variations and modifications can be made without departing from the concept of the present invention, and these all fall into the protection scope of the present invention.
Claims (2)
1. The homogeneous bismaleimide triazine resin containing cyano and phenolphthalein side groups is characterized in that the homogeneous bismaleimide triazine resin is prepared by mixing bismaleimide monomers MCBMI containing cyano and phenolphthalein side groups with bisphenol A type cyanate BADCy, and the homogeneous bismaleimide triazine resin has the following system structure:
the homogeneous bismaleimide triazine resin containing the cyano and the phenolphthalein side group is prepared by the following steps:
heating and melting bisphenol A type cyanate ester BADCy, adding bismaleimide resin MCBMI containing cyano and phenolphthalein side groups, stirring and reacting at 120-140 ℃ to obtain uniform transparent liquid, placing the obtained mixed system in a vacuum oven at the same temperature for defoaming for 40-60 min, curing according to a curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the MCBMI/BADCy homogeneous phase resin system; the weight ratio of the bismaleimide resin MCBMI to the bisphenol A cyanate BADCy is 1: 2-1: 5.
2. The homogeneous bismaleimide triazine resin containing cyano and phenolphthalein side groups is prepared by mixing bismaleimide monomers MCBMI containing cyano and phenolphthalein side groups, bisphenol A cyanate ester BADCy and diallyl bisphenol A, wherein the homogeneous bismaleimide triazine resin system is formed by mutually intertwining the following two structures (a) and (b) to form a uniform IPN structure:
the homogeneous bismaleimide triazine resin containing the cyano and the phenolphthalein side group is prepared by the following steps:
mixing bisphenol A cyanate ester BADCy and diallyl bisphenol A DABPA, heating and melting at 120-140 ℃, uniformly stirring, adding bismaleimide resin MCBMI containing cyano and phenolphthalein side groups, taking diallyl bisphenol A as a modifier and a catalyst, stirring at the same temperature to obtain a uniform transparent system, placing the obtained mixed system in a vacuum oven at the same temperature for defoaming for 40-60 min, curing according to a curing process of 150 ℃ multiplied by 4h +200 ℃ multiplied by 4h +240 ℃ multiplied by 2h, and naturally cooling to room temperature to obtain the MCBMI/BADCy/DABPA homogeneous resin system; the mass ratio of the total mass of MCBMI and DABPA to BADCy is 1: 2-1: 5, and the mass ratio of DABPA to MCBMI is 1: 0.8-1.2.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104629052A (en) * | 2015-01-16 | 2015-05-20 | 沈阳航空航天大学 | Bismaleimide resin containing cyano group and phthalidyl side group and preparation method thereof |
| CN105153009A (en) * | 2015-06-23 | 2015-12-16 | 复旦大学 | Bimaleimide with asymmetric molecular structure and preparation methods thereof, and application of bimaleimide in preparation of composite resin |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104629052A (en) * | 2015-01-16 | 2015-05-20 | 沈阳航空航天大学 | Bismaleimide resin containing cyano group and phthalidyl side group and preparation method thereof |
| CN105153009A (en) * | 2015-06-23 | 2015-12-16 | 复旦大学 | Bimaleimide with asymmetric molecular structure and preparation methods thereof, and application of bimaleimide in preparation of composite resin |
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