阅读说明：本技术 一种含磷的反应型阻燃剂环氧树脂组合物、覆铜板及阻燃剂的制备方法 (Phosphorus-containing reactive flame retardant epoxy resin composition, copper-clad plate and preparation method of flame retardant ) 是由 潘庆崇 于 2019-08-28 设计创作，主要内容包括：本发明提供了一种含磷的反应型阻燃剂环氧树脂组合物、覆铜板及阻燃剂的制备方法,所述含磷的反应型阻燃剂由带有-P-H反应基团的化合物与含有碳氮不饱和键的化合物通过加成反应得到；本发明提供的含磷的反应型阻燃剂结构新颖,应用范围广,结构中含有活性氨基,能够参与到复合材料的反应中,使得复合材料的稳定性增强,阻燃性提高,并且不会受到水等因素的影响,同时具有良好的物理性能和强度,应用前景良好。(The invention provides a preparation method of a phosphorus-containing reactive flame retardant epoxy resin composition, a copper-clad plate and a flame retardant, wherein the phosphorus-containing reactive flame retardant is obtained by an addition reaction of a compound with a-P-H reactive group and a compound containing a carbon-nitrogen unsaturated bond; the phosphorus-containing reactive flame retardant provided by the invention has the advantages of novel structure and wide application range, contains active amino groups in the structure, can participate in the reaction of the composite material, enhances the stability of the composite material, improves the flame retardance, is not influenced by factors such as water and the like, and has good physical properties and strength and good application prospect.)

1. The phosphorus-containing reactive flame retardant is characterized in that the phosphorus-containing reactive flame retardant is obtained by an addition reaction of a compound with a-P-H reactive group and a compound containing a carbon-nitrogen unsaturated bond.

2. The reactive phosphorus-containing flame retardant of claim 1, wherein the compound having a reactive group-P-H has a structure according to formula I:

wherein X is a VI main group element or is absent, L₁、L₂Each independently is preferably alkyl, cycloalkyl, aryl, heteroaryl, alkoxy, alkanoyl or aryloxy, or L₁And L₂Are connected into a ring.

3. The reactive phosphorus-containing flame retardant according to claim 2, wherein X is preferably an oxygen atom or a sulfur atom, and more preferably an oxygen atom.

4. The reactive phosphorus-containing flame retardant of claim 2 or 3, wherein L is₁、L₂Are each independently preferably C₁-C₅Alkoxy group of (C)₆-C₉Aryl or C of₆-C₉Aryloxy group of, or L₁And L₂Are connected into a ring.

5. According to the claimsThe reactive flame retardant containing phosphorus according to any one of claims 1 to 4, wherein the reactive flame retardant containing phosphorus is preferably one containing phosphorus Any one of them.

6. The reactive flame retardant containing phosphorus according to any one of claims 1 to 5, wherein the reactive flame retardant containing phosphorus is preferably one containing phosphorus

7. The method according to any one of claims 1 to 6, wherein the compound having a-P-H reactive group is subjected to an addition reaction with a compound having a carbon-nitrogen unsaturated bond to obtain the phosphorus-containing reactive flame retardant.

8. The epoxy resin composition is characterized by comprising the following components in parts by weight: the phosphorus-containing reactive flame retardant according to any one of claims 1 to 6, which comprises 20 to 40 parts of a bisphenol A epoxy resin and 0.2 to 1 part of 2-methylimidazole, and which is further characterized by comprising 80 to 120 parts of a bisphenol A epoxy resin.

9. A copper-clad plate, characterized in that it comprises the epoxy resin composition according to claim 8.

Technical Field

The invention belongs to the field of flame retardants, and relates to a phosphorus-containing reactive flame retardant epoxy resin composition, a copper-clad plate and a preparation method of a flame retardant.

Background

Flame retardants used in polyurethane materials are classified into additive flame retardants and reactive flame retardants. The additive flame retardant has been widely applied to the actual production of polyurethane flame retardance due to good flame retardant effect and relatively simple production process, but the problems of large addition amount, easy precipitation, product performance reduction and the like restrict the further application of the additive flame retardant. The reactive flame retardant introduces flame retardant elements such as phosphorus and the like into the polyurethane raw material isocyanate and polyether polyol, so that the polyurethane composite material has better flame retardant property and mechanical property.

CN103694434A discloses a halogen-free reaction type flame retardant for polyurethane foam and a preparation method and application thereof, the halogen-free reaction type flame retardant is prepared by 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), alcohol amine and formaldehyde react through Mannich reaction, the structural formula is that the halogen-free reaction type flame retardant adopts Mannich reaction to introduce the alcohol amine and the formaldehyde into a DOPO flame retardant structure, the cost of the flame retardant is reduced, the synthesized halogen-free reaction type flame retardant contains active hydroxyl, flame-retardant nitrogen and phosphorus elements, primary amine or tertiary amine, the reaction activity is higher, a rigid benzene ring is used for flame-retardant polyurethane foam, the flame retardance is higher, the strength and the flame-retardant durability of the foam are increased, and the oxygen index can reach 23-28%. Has wide application prospect in construction, heat preservation and some special occasions. However, the method has low synthesis yield and poor economic benefit.

CN105646813A discloses a reactive flame retardant applied to polyurethane materials and a preparation method thereof. The flame retardant is tetrabromophthalic acid (2-hydroxyethyl diethyl phosphonate methylene) amino mono-2-ethyl ester containing three flame retardant elements of bromine, phosphorus and nitrogen, and the specific preparation steps are that firstly, reactants of tetrabromophthalic anhydride, N-bis (2-hydroxyethyl) amino diethyl methylenephosphonate and solvent are added into a reaction vessel; stirring until tetrabromobenzene anhydride is completely dissolved, heating to 60-120 ℃ under the stirring condition, reacting for 2-12 hours, and synthesizing TBPAHM; after the reaction is finished, cooling to below 50 ℃, filtering, distilling and recovering the solvent to obtain the viscous TBPAHM. This method provides flame retardants containing halogens, which affect their properties.

CN105061511A discloses a bridged cyclophosphazene reactive flame retardant and a preparation method thereof, wherein hexachlorocyclotriphosphazene is used as a raw material, two phosphazene rings are bridged through a rigid structure, and then substitution reaction is carried out on aniline to obtain the bridged cyclophosphazene reactive flame retardant. The two novel flame retardants have the characteristics of high rigidity, large steric hindrance, multiple active points, high content of phosphorus and nitrogen elements and the like, have excellent thermal stability, can be applied to epoxy resin as a reactive flame retardant, do not release toxic gases such as hydrogen halide and the like during combustion due to the fact that the two novel flame retardants do not contain halogen, and accord with the development trend of green environmental protection of the current flame retardant. However, the method has the disadvantages of complex preparation process, low yield and no contribution to large-scale production and application.

At present, the existing phosphorus-containing reactive flame retardant has the problems of complex preparation process and low physical property, stability and flame retardance, and how to develop a novel reactive flame retardant has important significance for application.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a phosphorus-containing reactive flame retardant epoxy resin composition, a copper-clad plate and a preparation method of a flame retardant, so as to solve the problems of complex preparation process, low yield, poor flame retardance and poor stability of the existing phosphorus-containing flame retardant.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the invention provides a phosphorus-containing reactive flame retardant obtained by an addition reaction of a compound having a-P-H reactive group and a compound having a carbon-nitrogen unsaturated bond.

The phosphorus-containing reactive flame retardant provided by the invention is novel in structure and wide in application range. The structure contains active amino groups, and the active amino groups can participate in the reaction of the composite material, so that the stability of the composite material is enhanced, the flame retardance is improved, the composite material cannot be influenced by factors such as water and the like, and the composite material has good physical properties and strength and a good application prospect.

Preferably, the compound having a-P-H reactive group has the structure shown in formula I:

wherein X is a VI main group element or is absent, L₁、L₂Each independently is preferably alkyl, cycloalkyl, aryl, heteroaryl, alkoxy, alkanoyl or aryloxy, or L₁And L₂Are connected into a ring.

Preferably, X is an oxygen atom or a sulfur atom, and further preferably an oxygen atom.

Preferably, said L₁、L₂Are each independently preferably C₁-C₅Alkoxy group of (C)₆-C₉Aryl or C of₆-C₉Aryloxy group of, or L₁And L₂Are connected into a ring.

Wherein, C₁-C₅May be C₁、C₂、C₃、C₄Or C₅Etc. C₆-C₉May be C₆、C₇、C₈Or C₉And the like.

Illustratively, the compound having a-P-H reactive group may be 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), dimethyl phosphite, diethyl phosphite or diphenyl phosphite, and the like.

Preferably, the compound having a carbon-nitrogen unsaturated bond is an isocyanate group-containing compound and/or a cyano group-containing compound.

Preferably, the isocyanate group-containing compound has the structure Wherein R is₁、R₂Selected from any one of alkyl, aryl, substituted alkyl or substituted aryl or the combination of at least two of the same.

In the present invention, the alkyl group may be a straight-chain alkyl group, or an alkyl group having a branched chain, and may have a cyclic structure, a spiro structure, or the like. The aryl of the invention can be aromatic compounds with benzene, naphthalene, anthracene, phenanthrene and other structures, and the heteroaryl refers to compounds with aromaticity containing atoms of sulfur, nitrogen and oxygen.

Preferably, the cyano group-containing compound has the structureWherein R is₃Selected from any one of alkyl, aryl, substituted alkyl or substituted aryl or the combination of at least two of the same.

The substitution in the present invention refers to the substitution of alkyl or aryl groups by any substituent, such as hydroxyl, amino, carboxyl, cyano, etc., which are well known to those skilled in the art.

Preferably, the phosphorus-containing reactive flame retardant is preferably

Any one of them.

Preferably, the phosphorus-containing reactive flame retardant is preferably

In a second aspect, the invention provides a method for preparing the phosphorus-containing reactive flame retardant according to the first aspect, wherein the method comprises the step of carrying out addition reaction on a compound with a-P-H reactive group and a compound containing a carbon-nitrogen unsaturated bond to obtain the phosphorus-containing reactive flame retardant.

In a third aspect, the present invention provides an epoxy resin composition, comprising the following components in parts by weight: the first aspect of the present invention provides 20 to 40 parts of a phosphorus-containing reactive flame retardant, 80 to 120 parts of a bisphenol A epoxy resin, and 0.2 to 1 part of 2-methylimidazole.

In a fourth aspect, the invention provides a copper-clad plate, which comprises the epoxy resin composition as described in the third aspect.

Compared with the prior art, the invention has the following beneficial effects:

the phosphorus-containing reactive flame retardant provided by the invention is novel in structure and wide in application range. The structure contains active amino groups, can participate in the reaction of the composite material, enhances the stability of the composite material, improves the flame retardance, is not influenced by factors such as water and the like, has good physical properties and strength, avoids the precipitation phenomenon of the existing flame retardant, has good application prospect, and is suitable for industrial production.

Detailed Description

The technical solution of the present invention is further explained by the following embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.

Example 1

The embodiment provides a phosphorus-containing reactive flame retardant, which has the following structure:

the preparation method comprises the following steps:

adding 4mol of dimethyl phosphite, 1mol of glutaronitrile and 50mL of ethanol into a three-neck flask with a magnetic stirring thermometer, controlling the temperature below 5 ℃ in an ice-water bath under stirring, dropwise adding 2mol of trifluoromethanesulfonic anhydride, gradually heating and refluxing, continuing to react for 1h, and carrying out reduced pressure distillation to obtain the reactive flame retardant with the structure.

¹H NMR(400MHz,DMSO-d₆)δ3.42(d,J＝10.8Hz,24H),2.61(s,4H),1.82(t,J＝7.8Hz,4H),1.28(p,J＝7.8Hz,2H).

Example 2

The embodiment provides a phosphorus-containing reactive flame retardant, which has the following structure:

the preparation method comprises the following steps:

adding 2mol of DOPO, 1mol of 2, 4-toluene diisocyanate and 100mL of toluene into a three-neck flask with a magnetic stirring thermometer, dropwise adding 2mol of titanium tetrachloride while stirring, carrying out reflux reaction for 6h, carrying out hydrochloric acid quenching reaction, washing the organic phase after water washing, and evaporating the solvent to dryness to obtain the phosphorus-containing reactive flame retardant.

¹H NMR(400MHz,DMSO-d₆)δ13.87(s,1H),9.46(s,1H),8.04–7.14(m,20H),2.20(d,J＝1.0Hz,3H).

Example 3

The embodiment provides a phosphorus-containing reactive flame retardant, which has the following structure:

the preparation method comprises the following steps:

1mol of dimethyl phosphite, 1mol of 2, 6-diisopropylbenzene isocyanate and 200mL of toluene are added into a three-neck flask with a magnetic stirring thermometer, 1mol of titanium tetrachloride is dripped under stirring, reflux reaction is carried out for 4 hours, hydrochloric acid quenching reaction is carried out, and after an organic phase is washed by water, the solvent is evaporated to dryness to obtain the phosphorus-containing reactive flame retardant.

¹H NMR(400MHz,DMSO-d₆)δ7.28–7.07(m,3H),3.78(d,J＝10.9Hz,6H),2.80(m,2H),1.10(d,J＝6.8Hz,12H).

Example 4

The embodiment provides a phosphorus-containing reactive flame retardant, which has the following structure:

the preparation method comprises the following steps:

adding 2mol of DOPO, 1mol of 1, 6-hexamethylene diisocyanate and 200mL of toluene into a three-neck flask with a magnetic stirring thermometer, dropwise adding 1mol of titanium tetrachloride while stirring, carrying out reflux reaction for 3h, carrying out hydrochloric acid quenching reaction, washing the organic phase after water washing, and evaporating the solvent to dryness to obtain the phosphorus-containing reactive flame retardant.

¹H NMR(400MHz,DMSO-d₆)δ9.77(s,1H),8.04–7.16(m,17H),3.06(t,J＝7.4Hz,4H),1.63–1.52(m,4H),1.44–1.34(m,4H).

Example 5

The embodiment provides a phosphorus-containing reactive flame retardant, which has the following structure:

the preparation method comprises the following steps:

adding 1mol of dimethyl phosphite, 1mol of n-butyl isocyanate and 100mL of toluene into a three-neck flask with a magnetic stirring thermometer, dropwise adding 1mol of titanium tetrachloride while stirring, carrying out reflux reaction for 2 hours, carrying out hydrochloric acid quenching reaction, washing the organic phase with water, and evaporating the solvent to dryness to obtain the phosphorus-containing reactive flame retardant.

¹H NMR(400MHz,DMSO-d₆)δ8.54(s,1H),3.78(d,J＝10.9Hz,6H),3.06(t,J＝7.6Hz,2H),1.48(p,J＝7.7Hz,2H),1.35–1.22(m,2H),0.88(t,J＝6.5Hz,3H).

Example 6

The embodiment provides a phosphorus-containing reactive flame retardant, which has the following structure:

the preparation method comprises the following steps:

2mol of diphenyl phosphite, 1mol of 2, 6-toluene diisocyanate and 250mL of toluene are added into a three-neck flask with a magnetic stirring thermometer, 2mol of titanium tetrachloride is dripped into the flask under stirring, reflux reaction is carried out for 2 hours, hydrochloric acid is used for quenching reaction, and after an organic phase is washed by water, the solvent is evaporated to dryness to obtain the phosphorus-containing reactive flame retardant.

¹H NMR(400MHz,DMSO-d₆)δ10.99(s,1H),10.85(s,1H),7.76(d,J＝7.6Hz,2H),7.44–7.12(m,22H),2.33(s,3H).

Example 7

The embodiment provides a phosphorus-containing reactive flame retardant, which has the following structure:

the preparation method comprises the following steps:

adding 2mol of diethyl phosphite, 1mol of benzyl cyanide and 250mL of toluene into a three-neck flask with a magnetic stirring thermometer, dropwise adding 2mol of titanium tetrachloride while stirring, carrying out reflux reaction for 2h, carrying out hydrochloric acid quenching reaction, washing the organic phase with water, and evaporating the solvent to dryness to obtain the phosphorus-containing reactive flame retardant.

¹H NMR(400MHz,DMSO-d₆)δ7.40–7.15(m,5H),3.98(dp,J＝12.5,8.1Hz,4H),3.73–3.60(m,4H),3.21(s,2H),2.60(s,2H),1.36(t,J＝8.0Hz,12H).

The phosphorus-containing reactive flame retardants provided in examples 1 to 7 were applied to epoxy resin compositions corresponding to the epoxy resin compositions 1 to 7, respectively, and specifically included the following components: 30 parts of phosphorus-containing reactive flame retardant, 100 parts of bisphenol A epoxy resin and 1 part of 2-methylimidazole, and if the curing effect of the phosphorus-containing reactive flame retardant is insufficient, dicyandiamide is used for supplementing.

Comparative example 1

This comparative example is different from the above epoxy resin composition in that the phosphorus-containing reactive flame retardant is completely replaced with a dicyandiamide curing agent.

Comparative example 2

This comparative example differs from comparative example 1 in that 30 parts of triphenyl phosphate was added as a flame retardant.

Comparative example 3

This comparative example differs from comparative example 1 in that 45 parts of triphenyl phosphate is added as a flame retardant.

Performance testing

The epoxy resin compositions 1 to 7 and the epoxy resin compositions provided in comparative examples 1 to 3 were prepared into copper clad laminates according to a known conventional method, and the following tests were performed:

(1)T_g: differential scanning calorimetry (D)SC), measured by the DSC method defined in IPC-TM-650 as 2.4.25;

(2) interlayer peel strength PS: testing the peel strength of the plate according to the experimental conditions of 'after thermal stress' in the IPC-TM-6502.4.8 method;

(3) dielectric constant (Dk) and dielectric loss factor (Df): testing the dielectric constant Dk and the dielectric loss Df of the board by adopting an SPDR method under the frequency of 10 GHz;

(5) combustibility: testing according to UL-94 vertical burning test standard;

(6) flame retardant stability: soaking the copper-clad plate in water for 1h, drying and measuring the combustibility of the copper-clad plate again;

(7) mobility: and baking the copper-clad plate at 150 ℃ for 2h, and testing the weight difference percentage before and after baking.

The test results are shown in table 1:

TABLE 1

The results in table 1 show that the copper clad laminate prepared by using the phosphorus-containing reactive flame retardant provided by the invention has excellent performance, wherein the glass transition temperature is higher than 173 ℃, the peel strength is higher than 0.75N/mm, the dielectric constant is lower than 3.66(10GHz), and the dielectric loss is lower than 0.0078(10 GHz).

Compared with a comparative example, the additive flame retardant can affect the stability and physical properties of the copper-clad plate, and the flame retardance is reduced, so that the phosphorus-containing reactive flame retardant provided by the invention has good flame retardance and excellent flame retardance stability.

As can be seen from the comparison of the compounds between the examples provided by the present invention, the compounds of different structures exhibit different physical properties and stability, but all have good flame retardancy.

The applicant states that the present invention is illustrated by the above examples to the preparation method of the phosphorus-containing reactive flame retardant epoxy resin composition, the copper clad laminate and the flame retardant of the present invention, but the present invention is not limited to the above detailed method, that is, the present invention is not meant to be implemented by relying on the above detailed method. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.