A phosphorus-containing flame-retardant epoxy resin and a preparation method thereof

Abstract

The application provides a phosphorus-containing flame-retardant epoxy resin and a preparation method thereof, and belongs to the technical field of flame-retardant resins.The phosphorus-containing flame-retardant epoxy resin is prepared from raw materials with the following mass percentage: epoxy resin 35-65%; FR007 flame retardant 10-20%; triphenylphosphine 0.02-0.05%; equivalent modified resin 0-25%; polar organic solvent 20-40%; the effective component of the FR007 flame retardant includes diphenyl phosphine oxide; and the equivalent modified resin is o-methyl phenol formaldehyde resin and / or bisphenol A type epoxy resin.The phosphorus-containing flame-retardant epoxy resin has low cost, the cost of the flame retardant FR007 is 70-90 thousand yuan / ton, which is much lower than that of the flame-retardant epoxy resin doped with DOPO flame retardant, but the heat resistance and flame-retardant performance can be comparable to those of the flame-retardant epoxy resin doped with DOPO flame retardant.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flame-retardant resin, in particular to a phosphorus-containing flame-retardant epoxy resin and a preparation method thereof. BACKGROUND

[0002] Epoxy resin is widely used in daily life, but its oxygen index is low, and it is a flammable material, so it needs to be modified with a flame retardant for further use. The commonly used flame retardants on the market include halogen-based flame retardants, phosphorus-containing flame retardants, inorganic flame retardants, etc.

[0003] Among them, phosphorus-containing flame retardants have been most widely used due to their advantages of small dosage, no effect on material processing, high efficiency, small environmental hazard, low smoke, low toxicity, etc. The flame-retardant principle of the current phosphorus-containing flame retardant mainly includes: the condensed phase flame retardation of the flame retardant itself decomposing to generate non-combustible material covering the material surface, the synergistic flame retardation of adding multiple other flame retardants in a single flame retardant to achieve flame retardation effect, and the gas phase flame retardation of the flame retardant itself decomposing to generate gaseous substances that are not easy to burn to reduce the concentration of combustion-supporting agent (oxygen) in the air.

[0004] The current existing phosphorus-containing flame retardants include TBBA, DOPO and DOPO derivatives, HPTCP, etc. Among them, DOPO series flame retardants are widely used in the epoxy resin industry due to their good performance. However, the price of DOPO series phosphorus-containing flame retardants has been rising in recent years, which limits their industrial use. SUMMARY

[0005] Therefore, the present application aims to provide a phosphorus-containing flame-retardant epoxy resin and a preparation method thereof. The phosphorus-containing flame-retardant epoxy resin provided by the present application has low cost and performance comparable to that of a flame-retardant epoxy resin doped with DOPO.

[0006] In order to achieve the above-mentioned application purposes, the present application provides the following technical solutions:

[0007] The present application provides a phosphorus-containing flame-retardant epoxy resin, which is prepared from raw materials including the following mass percentages:

[0008]

[0009]

[0010] The effective component of the FR007 flame retardant includes diphenyl phosphine oxide;

[0011] The equivalent modified resin is o-methyl phenolic resin and / or bisphenol A type epoxy resin. The epoxy equivalent weight of the o-methyl phenolic resin is 200-230 g / eq, and the epoxy equivalent weight of the bisphenol A type epoxy resin is 6000-7000 g / eq.

[0012] Preferably, the epoxy resin is a bisphenol A type epoxy resin and / or a phenol type epoxy resin.

[0013] Preferably, the epoxy equivalent weight of the epoxy resin is 200-800 g / eq.

[0014] Preferably, the phosphorus content of the phosphorus-containing flame-retardant epoxy resin is 1.5-4.5 wt%.

[0015] Preferably, the polar organic solvent is butanone.

[0016] The present application provides a preparation method of the above-mentioned phosphorus-containing flame-retardant epoxy resin, comprising the following steps:

[0017] The epoxy resin and the first portion of FR007 flame retardant are mixed by first heating to obtain a first mixture;

[0018] The first mixture and triphenylphosphine are mixed by second heating to obtain a second mixture;

[0019] The remaining FR007 flame retardant is added to the second mixture in multiple times and mixed by third heating to obtain a third mixture;

[0020] The third mixture, the equivalent modified resin, and the polar organic solvent are mixed by fourth heating to obtain the phosphorus-containing flame-retardant epoxy resin.

[0021] Preferably, the mass of the first portion of FR007 flame retardant is 25-50% of the total mass of FR007 flame retardant.

[0022] Preferably, the first heating is performed at a temperature of 80-120°C for 30-90 min.

[0023] The second heating is performed at a temperature of 80-120°C for 30-150 min.

[0024] Preferably, when the remaining FR007 flame retardant is added to the second mixture in multiple times, the interval between two adjacent additions is ≥30 min.

[0025] Preferably, the third heating is performed at a temperature of 140-154°C for 60-180 min.

[0026] The fourth heating is performed at a temperature of 50-160°C for 30-90 min.

[0027] The present invention provides a phosphorus-containing flame-retardant epoxy resin, prepared from the following raw materials in percentage by weight: 35-65% epoxy resin; 10-20% FR007 flame retardant; 0.02-0.05% triphenylphosphine; 0-25% equivalent-modified resin; and 20-40% polar organic solvent. The FR007 flame retardant comprises diphenylphosphine as an active ingredient; the equivalent-modified resin is o-methylphenol-formaldehyde resin and / or bisphenol A epoxy resin, the o-methylphenol-formaldehyde resin having an epoxy equivalent weight of 200-230 g / eq; and the bisphenol A epoxy resin having an epoxy equivalent weight of 6000-7000 g / eq. The present invention uses the FR007 flame retardant to flame-retard the epoxy resin. The FR007 flame retardant reacts with epoxy groups in the epoxy resin under the action of the catalyst triphenylphosphine, with each molecule of the FR007 flame retardant consuming one molecule of epoxy, ultimately producing the phosphorus-containing epoxy resin. The phosphorus-containing flame-retardant epoxy resin provided by the present invention has low cost. The cost of flame retardant FR007 is 70,000 to 90,000 yuan per ton, which is much lower than the cost of DOPO of 100,000 to 120,000 yuan per ton. However, its heat resistance and flame retardant properties are comparable to those of flame-retardant epoxy resin doped with DOPO flame retardant. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is the Tg diagram of the phosphorus-containing flame-retardant epoxy resin obtained in Example 1;

[0029] Figure 2 This is the Tg diagram of the phosphorus-containing flame-retardant epoxy resin obtained in Example 2;

[0030] Figure 3 This is the Tg diagram of the phosphorus-containing flame-retardant epoxy resin obtained in Example 3;

[0031] Figure 4 This is the Tg diagram of the phosphorus-containing flame-retardant epoxy resin obtained in Example 4;

[0032] Figure 5 This is the Tg diagram of the phosphorus-containing flame-retardant epoxy resin obtained in Example 5. DETAILED DESCRIPTION

[0033] The present invention provides a phosphorus-containing flame-retardant epoxy resin, which is prepared from raw materials comprising the following mass percentages:

[0034]

[0035] The active ingredients of the FR007 flame retardant include diphenylphosphine;

[0036] The equivalent modified resin is o-methylphenol-formaldehyde resin and / or bisphenol A epoxy resin, the epoxy equivalent of the o-methylphenol-formaldehyde resin is 200-230 g / eq; the epoxy equivalent of the bisphenol A epoxy resin is 6000-7000 g / eq.

[0037] The raw materials used in the present application are commercially available unless otherwise specified.

[0038] The phosphorus-containing flame-retardant epoxy resin provided by the present application comprises 35-65% of epoxy resin, preferably 40-60%, and further preferably 45-55% by mass percentage. In the present application, the epoxy resin is preferably bisphenol A type epoxy resin and / or phenolic type epoxy resin. In the present application, the epoxy equivalent of the epoxy resin is preferably 200-800 g / eq, and more preferably 400-600 g / eq. As a specific embodiment of the present application, the epoxy resin is preferably 638 resin.

[0039] The phosphorus-containing flame-retardant epoxy resin provided by the present application comprises 10-20% of FR007 flame retardant, preferably 12-18%, and more preferably 15% by mass percentage. In the present application, the effective ingredient of the FR007 flame retardant comprises diphenyl phosphine oxide. In the present application, the CAS number of the FR007 flame retardant is preferably 4559-70-0. FR007 flame retardant is a phosphorus-containing halogen-free reactive flame retardant, which has good stability, thermal decomposition temperature is about 150℃, and the phosphorus content is 14.5-15.7 wt%, which is higher than DOPO. In the present application, the FR007 flame retardant is preferably purchased from Shanghai Sainuo Chemical Technology Co., Ltd.

[0040] The phosphorus-containing flame-retardant epoxy resin provided by the present application comprises 0.02-0.05% of triphenylphosphine, preferably 0.03-0.04% by mass percentage. In the present application, the triphenylphosphine acts as a catalyst.

[0041] The phosphorus-containing flame-retardant epoxy resin provided by the present application comprises 0-25% of equivalent modified resin, preferably 5-20%, and more preferably 10-15% by mass percentage. In the present application, the equivalent modified resin is o-methyl phenolic resin and / or bisphenol A type epoxy resin, the epoxy equivalent of the o-methyl phenolic resin is 200-230 g / eq, preferably 210-220 g / eq; and the epoxy equivalent of the bisphenol A type epoxy resin is preferably 6000-7000 g / eq, and more preferably 6200-6800 g / eq. In the present application, the equivalent modified resin plays a role in increasing the epoxy equivalent value of the phosphorus-containing flame-retardant epoxy resin.

[0042] The phosphorus-containing flame-retardant epoxy resin provided by the present application comprises 20-40% of polar organic solvent, preferably 25-35%, and further preferably 30% by mass percentage. In the present application, the polar organic solvent is preferably butanone.

[0043] In the present application, the phosphorus content of the phosphorus-containing flame-retardant epoxy resin is preferably 1.5-4.5 wt%, more preferably 2-4 wt%, and further preferably 2.5-3.5 wt%.

[0044] The present application provides a preparation method of the above-mentioned phosphorus-containing flame-retardant epoxy resin, comprising the following steps:

[0045] The epoxy resin and the first portion of FR007 flame retardant are subjected to first heating mixing to obtain a first mixture.

[0046] The first mixture and triphenylphosphine are subjected to second heating mixing to obtain a second mixture.

[0047] The remaining FR007 flame retardant is added to the second mixture in multiple times, and subjected to third heating mixing to obtain a third mixture.

[0048] The third mixture, modified resin, and polar organic solvent are subjected to fourth mixing to obtain the phosphorus-containing flame-retardant epoxy resin.

[0049] In the present application, the first portion of FR007 flame retardant has a mass of preferably 25-50% of the total mass of FR007 flame retardant, and more preferably 30-40%.

[0050] In the present application, the second heating mixing is preferably performed under stirring; the temperature of the second heating mixing is preferably 80-120°C, and more preferably 100-110°C; and the time is preferably 30-150 min, and more preferably 60-120 min.

[0051] In the present application, the remaining FR007 flame retardant is preferably added to the second mixture in three times. In the present application, when the remaining FR007 flame retardant is added to the second mixture in multiple times, the interval between two adjacent additions is ≥30 min. In the present application, the temperature of the third heating mixing is preferably 140-154°C, and more preferably 145-150°C; and the time is preferably 60-180 min, and more preferably 90-120 min. The time of the third heating mixing is calculated from the time when the remaining FR007 flame retardant is completely added.

[0052] The third mixture is mixed with an equivalent modified resin and a polar organic solvent to obtain a phosphorus-containing flame-retardant epoxy resin. In the present application, the temperature of the fourth heating and mixing is preferably 50-160°C, more preferably 90-120°C, and the time is preferably 30-90 min, more preferably 50-80 min.

[0053] In the present application, the first, second, third and fourth heating and mixing are preferably carried out under nitrogen protection.

[0054] In the present application, the phosphorus-containing flame-retardant epoxy resin is preferably used as a phosphorus-containing flame-retardant epoxy resin for copper-clad plates.

[0055] The phosphorus-containing flame-retardant epoxy resin and the preparation method thereof provided by the present application are described in detail below in conjunction with examples, but they should not be understood as limiting the scope of protection of the present application.

[0056] Example 1

[0057] Under nitrogen protection, 424.08 g of 638 epoxy resin was added to a 1 L reaction bottle, doped with 30.80 g of FR007 flame retardant, and the temperature was adjusted to 100°C, mixed for 70 min; then 0.20 g of catalyst triphenylphosphine was added, and mixed for 90 min; the temperature was raised to 148°C, and the flame retardant FR007 was added in three portions, each portion being 29.0 g, and after each portion was added, the temperature was maintained for more than 30 minutes before the next portion was added. After the last portion of FR007 was added, the temperature was maintained for two hours, and then 125.00 g of epoxy equivalent of 210 g / eq o-methyl phenolic resin and 41.00 g of epoxy equivalent of 6300 g / eq bisphenol A epoxy resin were added, and mixed at 120°C for 60 min, and then 250 g of solvent butanone was added and mixed for 20 min to obtain a phosphorus-containing flame-retardant epoxy resin, with a phosphorus content of 2.4%.

[0058] The thermogravimetric curve (Tg) of the phosphorus-containing flame-retardant epoxy resin obtained in Example 1 is shown in Figure 1 .

[0059] Example 2

[0060] Under the condition of nitrogen protection, 474.50 g of 638 epoxy resin was added into a 1 L reaction bottle, doped with 30.80 g of FR007, the temperature was adjusted to 100°C, and mixed for 70 min; then 0.20 g of catalyst triphenylphosphine was added, mixed for 90 min; the temperature was raised to 148°C, and the subsequent flame retardant FR007 was added in three stages, with each addition amount being 22.4 g, and after each addition, the next material was added after ensuring that the holding time was more than 30 minutes, after the last stage of FR007 was added, 184.40 g of bisphenol A type epoxy resin with an epoxy equivalent weight of 6300 g / eq and 100.0 g of o-methyl phenolic resin with an epoxy equivalent weight of 210 g / eq were added, mixed for 60 min at 120°C, 250 g of solvent butanone was added and mixed for 20 min, to obtain a phosphorus-containing flame-retardant epoxy resin with a phosphorus content of 2.0%.

[0061] The thermogravimetric curve (Tg) diagram of the phosphorus-containing flame-retardant epoxy resin obtained in Example 2 is shown in Figure 2 .

[0062] Example 3

[0063] Under the condition of nitrogen protection, 474.50 g of 638 epoxy resin was added into a 1 L reaction bottle, doped with 30.80 g of FR007, the temperature was adjusted to 100°C, and mixed for 70 min; then 0.20 g of catalyst triphenylphosphine was added, mixed for 90 min; the temperature was raised to 148°C, and the subsequent flame retardant FR007 was added in three stages, with each addition amount being 22.4 g, and after each addition, the next material was added after ensuring that the holding time was more than 30 minutes, after the last stage of FR007 was added, 184.40 g of bisphenol A type epoxy resin with an epoxy equivalent weight of 6300 g / eq and 100.0 g of o-methyl phenolic resin with an epoxy equivalent weight of 210 g / eq were added, mixed for 60 min at 120°C, 250 g of solvent butanone was added and mixed for 20 min, to obtain a phosphorus-containing flame-retardant epoxy resin with a phosphorus content of 2.0%.

[0064] The thermogravimetric curve (Tg) diagram of the phosphorus-containing flame-retardant epoxy resin obtained in Example 3 is shown in Figure 3 .

[0065] Example 4

[0066] Under the condition of nitrogen protection, 539.87 g of 638 epoxy resin was added into a 1 L reaction bottle, doped with 30.80 g of FR007, the temperature was adjusted to 100°C, and mixed for 70 min; then 0.20 g of catalyst triphenylphosphine was added, mixed for 90 min; the temperature was raised to 148°C, and the subsequent flame retardant FR007 was added in three stages, each time the amount was 46.9 g, and after each time, the next material was added after ensuring that the holding time was more than 30 minutes, and after the last stage of FR007 was added, it was held for two hours, 250 g of solvent butanone was added and mixed for 20 min, to obtain a phosphorus-containing flame-retardant epoxy resin, with a phosphorus content of 3.5%.

[0067] The thermogravimetric curve (Tg) of the phosphorus-containing flame-retardant epoxy resin obtained in Example 4 is shown in Figure 4

[0068] Example 5

[0069] Under the condition of nitrogen protection, 539.87 g of 638 epoxy resin was added into a 1 L reaction bottle, doped with 30.80 g of FR007, the temperature was adjusted to 100°C, and mixed for 70 min; then 0.20 g of catalyst triphenylphosphine was added, mixed for 90 min; the temperature was raised to 148°C, and the subsequent flame retardant FR007 was added in three stages, each time the amount was 46.9 g, and after each time, the next material was added after ensuring that the holding time was more than 30 minutes, and after the last stage of FR007 was added, it was held for two hours, 250 g of solvent butanone was added and mixed for 20 min, to obtain a phosphorus-containing flame-retardant epoxy resin, with a phosphorus content of 3.5%.

[0070] The thermogravimetric curve (Tg) of the phosphorus-containing flame-retardant epoxy resin obtained in Example 5 is shown in Figure 5

[0071] Comparative Example 1

[0072] Under the condition of nitrogen protection, 539.87 g of 638 epoxy resin was added into a 1 L reaction bottle, doped with 30.80 g of FR007, the temperature was adjusted to 100°C, and mixed for 70 min; then 0.20 g of catalyst triphenylphosphine was added, mixed for 90 min; the temperature was raised to 148°C, and the subsequent flame retardant FR007 was added in three stages, each time the amount was 46.9 g, and after each time, the next material was added after ensuring that the holding time was more than 30 minutes, and after the last stage of FR007 was added, it was held for two hours, 250 g of solvent butanone was added and mixed for 20 min, to obtain a phosphorus-containing flame-retardant epoxy resin, with a phosphorus content of 3.5%.

[0073] The epoxy equivalent, hydrolytic chlorine content, solid content, phosphorus content and Tg temperature of the phosphorus-containing flame-retardant epoxy resin obtained in Examples 1-5 and Comparative Example 1 are shown in Table 1. Among them, the determination of the epoxy equivalent was carried out according to GB / T 4612, using point titration method; the determination of the hydrolytic chlorine was carried out according to the provisions of GB / T 4618.2.

[0074] ​​Table 1: Test results of the phosphorus-containing flame-retardant epoxy resin obtained in Examples 1-5 and Comparative Example 1

[0075]

[0076] As can be seen from Table 1, the phosphorus-containing flame-retardant epoxy resin provided by the present application can be comparable to the DOPO-based epoxy resin in terms of flame-retardant and heat-resistant properties.

[0077] The above description is only preferred embodiments of the present application, and it should be pointed out that, for those skilled in the art, several improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A phosphorus-containing flame-retardant epoxy resin prepared from raw materials comprising the following mass percentages: Epoxy resin 35-65%; FR007 flame retardant 10-20%; Triphenylphosphine 0.02-0.05%; Equivalent modified resin 5-25%; Polar organic solvent 20-40%; The epoxy resin is a bisphenol A epoxy resin and / or a novolac epoxy resin; the epoxy equivalent of the epoxy resin is 200 to 800 g / eq; The active ingredients of the FR007 flame retardant include diphenylphosphine; The equivalent modified resin is o-methylphenol-formaldehyde resin and / or bisphenol A epoxy resin, the epoxy equivalent of the o-methylphenol-formaldehyde resin is 200-230 g / eq; the epoxy equivalent of the bisphenol A epoxy resin is 6000-7000 g / eq; The polar organic solvent is butanone; The preparation method of the phosphorus-containing flame-retardant epoxy resin comprises the following steps: Heat and mix the epoxy resin and the first portion of FR007 flame retardant to obtain a first mixture; subjecting the first mixture and triphenylphosphine to a second heating mixing to obtain a second mixture; adding the remaining FR007 flame retardant to the second mixture in multiple portions, performing a third heating and mixing process to obtain a third mixture; The third mixture is mixed with an equivalent modified resin and a polar organic solvent in a fourth step to obtain a phosphorus-containing flame-retardant epoxy resin.

2. The phosphorus-containing flame-retardant epoxy resin according to claim 1, characterized in that The phosphorus content of the phosphorus-containing flame-retardant epoxy resin is 1.5-4.5 wt %.

3. The method for preparing the phosphorus-containing flame-retardant epoxy resin according to claim 1 or 2, comprising the following steps: Heat and mix the epoxy resin and the first portion of FR007 flame retardant to obtain a first mixture; subjecting the first mixture and triphenylphosphine to a second heating mixing to obtain a second mixture; adding the remaining FR007 flame retardant to the second mixture in multiple portions, performing a third heating and mixing process to obtain a third mixture; The third mixture is mixed with an equivalent modified resin and a polar organic solvent in a fourth step to obtain a phosphorus-containing flame-retardant epoxy resin.

4. The preparation method according to claim 3, characterized in that The mass of the first portion of FR007 flame retardant is 25-50% of the total mass of the FR007 flame retardant.

5. The preparation method according to claim 3, characterized in that The first heating and mixing temperature is 80-120° C. and the time is 30-90 min; The temperature of the second heating and mixing is 80-120° C., and the time is 30-150 minutes.

6. The preparation method according to claim 3, characterized in that When the remaining FR007 flame retardant is added to the second mixture in multiple times, the interval between two adjacent additions is ≥30 minutes.

7. The preparation method according to claim 3 or 6, characterized in that The third heating and mixing is performed at a temperature of 140 to 154° C. for 60 to 180 minutes; The temperature of the fourth heating and mixing is 50-160° C., and the time is 30-90 minutes.

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