阅读说明：本技术 一种反应型磷杂菲/次磷酸盐双基阻燃环氧树脂材料及其制备方法 (Reactive phosphaphenanthrene/hypophosphite double-base flame-retardant epoxy resin material and preparation method thereof ) 是由 许博 马雯 许准 钱立军 赵建明 刘艳婷 王晶玉 于 2020-05-09 设计创作，主要内容包括：本发明公开一种反应型磷杂菲/次磷酸盐双基阻燃环氧树脂材料及其制备方法,该材料通过将含有反应基团的磷杂菲/次磷酸盐双基阻燃剂与环氧树脂分子通过化学反应键接,然后高温固化制备而成。该阻燃剂改善了物理添加所产生的相容性差和小分子迁移的问题,其引入的硅氧烷柔性链提高了材料的冲击强度,在较少的添加量下能够使环氧树脂材料通过UL94V-0级。该反应型磷杂菲/次磷酸盐双基阻燃环氧树脂材料具有优异的综合性能,在电子电器领域有较好的应用前景。(The invention discloses a reactive phosphaphenanthrene/hypophosphite biradical flame retardant epoxy resin material and a preparation method thereof. The flame retardant improves the problems of poor compatibility and small molecule migration caused by physical addition, the introduced siloxane flexible chain improves the impact strength of the material, and the epoxy resin material can pass through UL94V-0 grade under the condition of less addition amount. The reactive phosphaphenanthrene/hypophosphite biradical flame-retardant epoxy resin material has excellent comprehensive performance and has better application prospect in the field of electronic and electric appliances.)

1. A preparation method of a reactive phosphaphenanthrene/hypophosphite biradical flame-retardant epoxy resin material is characterized by comprising the following steps:

(1) adding phosphaphenanthrene/hypophosphite biradical flame retardant DH containing a reaction group into epoxy resin, heating and stirring until the DH is completely dissolved, and carrying out ring-opening addition reaction between hydroxyl on the DH and epoxy group in the epoxy resin at a certain temperature;

(2) after the reaction of DH and epoxy resin is finished, cooling to a certain temperature, adding a curing agent with equivalent weight to the residual epoxy group in the epoxy resin, stirring until the curing agent is fully dissolved or dispersed, removing air in a mixed system under a vacuum condition, heating and curing to prepare the target product reactive phosphaphenanthrene/hypophosphite double-base flame-retardant epoxy resin material.

2. The method for preparing a reactive phosphaphenanthrene/hypophosphite bis-based flame retardant epoxy resin material as claimed in claim 1, wherein the phosphaphenanthrene/hypophosphite bis-based flame retardant DH containing reactive groups in step (1) has the following general structural formula:

Mⁿ⁺＝Al³⁺、Zn²⁺、La³⁺、Ca²⁺、Co²⁺、Ni²⁺、Mn²⁺、Cu²⁺、Pb²⁺、Pd²⁺Or Ba²⁺

3. The method for preparing a reactive phosphaphenanthrene/hypophosphite bis-based flame retardant epoxy resin material as claimed in claim 1, wherein the epoxy resin in step (1) is a mixture of one or more of bisphenol A diglycidyl ether type epoxy resin with epoxy value of 0.41-0.54 and novolac epoxy resin.

4. The preparation method of the reactive phosphaphenanthrene/hypophosphite biradical flame retardant epoxy resin material as claimed in claim 1, wherein the mass ratio of the phosphaphenanthrene/hypophosphite biradical flame retardant containing the reactive group to the epoxy resin in the step (1) is 1:100-12: 100.

5. The method as claimed in claim 1, wherein the temperature of step (1) is increased to 180 ℃ for complete dissolution of DH, and the reaction temperature with epoxy resin is 120-170 ℃ for 1-8 hours.

6. The method for preparing a reactive phosphaphenanthrene/hypophosphite bis-based flame retardant epoxy resin material as claimed in claim 1, wherein the epoxy resin curing agent in step (2) is one or more of Dicyandiamide (DICY), 4 '-diaminodiphenyl sulfone (DDS), phenol novolac resin (PN) and 4, 4' -diaminodiphenylmethane (DDM) in combination.

7. The method for preparing a reactive phosphaphenanthrene/hypophosphite bis-based flame retardant epoxy resin material as claimed in claim 1, wherein the temperature decrease in step (2) is to 90-180 ℃, the curing temperature of the epoxy resin is 100-210 ℃, and the curing time is 3-18 hours.

8. A reactive phosphaphenanthrene/hypophosphite biradical flame-retardant epoxy resin material, which is characterized by being prepared by the method as claimed in any one of claims 1-7.

Technical Field

The invention relates to a reactive phosphaphenanthrene/hypophosphite double-base flame-retardant epoxy resin material and a preparation method thereof, belonging to the technical field of flame-retardant epoxy resin materials obtained by adding a specific flame-retardant auxiliary agent into common epoxy resin.

Background

High molecular materials are increasingly used in industrial and agricultural production and in clothing and eating. Among them, as a class of thermosetting polymer materials having good adhesion, electrical insulation, chemical resistance and low shrinkage, epoxy resins are widely used in the electronic and electrical industry, aerospace, transportation and military fields. However, the epoxy resin is flammable and difficult to self-extinguish, and the mechanical properties of most epoxy resins added with flame retardants are reduced, and even toxic substances are released in the combustion process, so that the application of the epoxy resin is limited. Therefore, it is necessary to develop a flame retardant epoxy resin material having excellent comprehensive properties.

According to the invention, a series of phosphaphenanthrene/hypophosphite double-base flame retardants (DH) containing reactive groups are used as reactive additives of the epoxy resin material, and siloxane flexible groups are introduced, so that two functions of high-efficiency flame retardance and toughening are realized, and the high-performance flame-retardant epoxy resin material with excellent comprehensive performance is obtained.

Disclosure of Invention

The invention aims to provide a reactive phosphaphenanthrene/hypophosphite diradical flame-retardant epoxy resin material and a preparation method thereof, aiming at overcoming the defects of the prior art, the halogen-free flame-retardant epoxy resin material with excellent comprehensive performance is prepared by utilizing the ring-opening addition reaction between the hydroxyl on a phosphaphenanthrene/hypophosphite diradical compound DH containing a reactive group and the epoxy group in epoxy resin, firstly bonding a certain amount of flame retardant on the molecular structure of the epoxy resin, then adding a proper amount of curing agent, and heating and curing.

The preparation process of the reactive phosphaphenanthrene/hypophosphite double-base flame-retardant epoxy resin material comprises the following steps:

(1) adding phosphaphenanthrene/hypophosphite biradical flame retardant DH containing a reaction group into epoxy resin, heating and stirring until the DH is completely dissolved, and carrying out ring-opening addition reaction between hydroxyl on the DH and epoxy group in the epoxy resin at a certain temperature;

(2) after the reaction of DH and epoxy resin is finished, cooling to a certain temperature, adding a curing agent with equivalent weight to the residual epoxy group in the epoxy resin, stirring until the curing agent is fully dissolved or dispersed, removing air in a mixed system under a vacuum condition, heating and curing to prepare the target product reactive phosphaphenanthrene/hypophosphite double-base flame-retardant epoxy resin material.

In the technical scheme, the phosphaphenanthrene/hypophosphite bis-based flame retardant DH containing the reactive group is a reactive additive of an epoxy resin material, and the structural general formula of a series of phosphaphenanthrene/hypophosphite bis-based flame retardants DH containing the reactive group is as follows:

the compound is prepared by respectively carrying out addition reaction on a P-H bond on 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and a P-H bond on hypophosphorous acid and two aldehyde groups on a dialdehyde compound, and then carrying out salt forming reaction on the compound and a metal compound; the preparation method comprises the following specific steps:

dissolving dialdehyde compound in first solvent, adding hypophosphorous acid (H)₂O50%), heating to 70-90 ℃, reacting for 12-48 h, adding 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), reacting for 4-24 h, dissolving a metal compound in deionized water, dropwise adding the metal compound into the reaction liquid within 0.5-2 h under mechanical stirring, reacting for 8-24 h, cooling to room temperature, performing suction filtration, washing the filtered solid with distilled water to be neutral, and drying to obtain the phosphaphenanthrene/hypophosphite biradical flame retardant containing the reaction group. The metal in the metal compound is Al³⁺、Zn²⁺、La³⁺、Ca²⁺、Co²⁺、Ni₂₊、Mn²⁺、Cu²⁺、Pb²⁺、Pd²⁺、Ba²⁺One kind of (1).

Wherein the dialdehyde compound can be silicon-containing dialdehyde compound but is not limited thereto, and can be selected from

One of (1); wherein the dialdehyde compound containing siliconIs prepared by dehydrochlorination condensation reaction between phenolic hydroxyl on p-hydroxybenzaldehyde and Si-Cl bond in dichlorosilane, and the preparation method comprises the following steps:

sufficiently dissolving p-hydroxybenzaldehyde in a second solvent at room temperature, adding an acid-binding agent, sealing, and sufficiently stirring for 15-30 min; slowly adding dichlorosilane into the solution by using an injector, heating to 40-70 ℃, reacting for 3-20 h, cooling to room temperature, carrying out suction filtration, and removing the solvent from the filtrate to obtain the dichlorosilane One kind of (1).

In the above technical solution, preferably, the epoxy resin in the step (1) is one or a mixture of two or more of bisphenol a diglycidyl ether type epoxy resin and novolac epoxy resin having an epoxy value of 0.41 to 0.54.

Preferably, the mass ratio of the phosphaphenanthrene/hypophosphite biradical flame retardant containing the reactive group to the epoxy resin in the step (1) is 1:100-12: 100.

Preferably, the dissolution temperature of the phosphaphenanthrene/hypophosphite bis-based flame retardant containing the reactive group in the step (1) is 100-180 ℃, the reaction temperature with the epoxy resin is 120-170 ℃, and the reaction time is 1-8 hours.

Preferably, the epoxy resin curing agent in step (2) is one or more of Dicyandiamide (DICY), 4 '-diaminodiphenyl sulfone (DDS), phenol novolac resin (PN), and 4, 4' -diaminodiphenylmethane (DDM).

Preferably, the dissolving or dispersing temperature of the curing agent in the step (2) is 90-180 ℃, the curing temperature of the epoxy resin is 100-210 ℃, and the curing time is 3-18 hours.

The reactive phosphaphenanthrene/hypophosphite double-base flame-retardant epoxy resin material prepared by the process realizes that the flame retardant can obtain excellent flame retardant property and impact resistance at low addition amount. Only 2 wt.% phosphaphenanthrene-p-phenyldimethylol-aluminium hypophosphite (DHA) flame retardant is added to the epoxy resin, the limiting oxygen index can reach 32.3% and pass UL94V-0 grade; the addition of 2 wt.% to 4 wt.% phosphaphenanthrene-methylvinylsiloxane-aluminum hypophosphite (DHAMVS) increases the impact strength of DDM cured bisphenol a glycidyl ether type epoxy resins by 30% to 50% and passes UL94V-0 grade; the reactive phosphaphenanthrene/hypophosphite double-base flame-retardant epoxy resin material effectively improves the flame-retardant efficiency and the impact resistance of the epoxy resin material, and has better application prospect in the fields of electronic appliances and the like.

Detailed Description