Preparation method of modified phenolic resin

Abstract

The invention relates to the technical field of phenolic resin, and in particular relates to a preparation method of modified phenolic resin. The preparation method comprises the following steps of: mixing a phenol organic compound with an aldehyde organic compound at pH of 7-11, and reacting until a matter which is insoluble in alkaline aqueous solution occurs, namely a phenol-aldehyde prepolymer is generated; and adding a phosphorus-containing organic compound in the phenol-aldehyde prepolymer, adjusting pH to be lower than 3, introducing inert gas, and reacting until phenol content is lower than 1% to obtain the modified phenolic resin. The preparation method for preparing modified phenolic resin is wide in production raw material sources and simple in synthesis process; and the phenolic resin prepared by using the preparation method is high in phosphorus content, so that the flame retardance of the phenolic resin is greatly improved and the synthesis ratio of the resin is improved.

Description

technical field

[0001] The invention relates to the technical field of phenolic resins, in particular to a preparation method of modified phenolic resins. Background technique

[0002] There are two types of phenolic resins, thermoplastic and thermosetting. Thermoplastic phenolic resin (or called two-step phenolic resin), is a light-colored to dark brown brittle solid, soluble in ethanol, acetone and other solvents, and has long-term solubility. It can be cured only in the presence of cross-linking agent (it can be cured quickly when heated), mainly used in the manufacture of compression molding powder, and also used in the manufacture of laminated plastics, varnishes and adhesives. Thermosetting phenolic resin (or one-step phenolic resin) can be made into solid, liquid and emulsion according to needs, and can be cross-linked and cured without cross-linking agent under the action of heat or (and) acid. In order to guide resin synthesis and molding processing, the curing ...

Examples

Embodiment 1

[0030] The obtained modified phenolic resin is subjected to post-treatment so that the phenol content is 0.8%, and the phosphorus-containing modified phenolic resin is obtained.

[0031] Example 2

[0032] The preparation method of modified phenolic resin comprises the steps:

[0033] (1) Mix 0.4 mol of phenol, 0.3 mol of m-phenol, and 0.3 mol of p-phenol into the reaction vessel, dissolve it in water at a temperature of 55-60 ° C, add barium hydroxide to adjust the pH to 7.5, and then add 1 mol of formaldehyde, Acetaldehyde 0.3mol, and heat up to 75-80°C, react, take a sample to detect if there is a substance insoluble in alkaline aqueous solution, stop the reaction, that is, generate a phenolic prepolymer;

Embodiment 2

[0035] The obtained modified phenolic resin is decompressed to -0.70~-0.60MPa, distilled, dehydrated and dephenolized, the phenol content is less than 0.9%, discharged, and cooled to obtain the desired phosphorus-containing modified phenolic resin.

[0036] Example 3

[0037] The preparation method of phosphorus-containing phenolic resin described in the present embodiment may further comprise the steps:

[0038] (1) Mix m-phenol 0.5mol and p-phenol 0.5mol, heat at 55-60°C to dissolve in water, add ammonium hydroxide to adjust pH to 11, then add formaldehyde 1.2mol, acetaldehyde 0.5mol, and heat up React at 75-80°C, take a sample to detect if there are substances insoluble in alkaline aqueous solution, stop the reaction, and generate a phenolic prepolymer;

Embodiment 3

[0040] The obtained modified phenolic resin is decompressed to -0.70~-0.60MPa, distilled, dehydrated and dephenolized, the phenol content is 0.5%, discharged, and cooled to obtain the desired phosphorus-containing modified phenolic resin.

[0041] Example 4

[0042] The preparation method of phosphorus-containing phenolic resin described in the present embodiment may further comprise the steps:

[0043] (1) Mix 0.4mol o-phenol, 0.4mol m-phenol, and 0.2mol p-phenol and heat at 45-50°C to dissolve in water, add sodium hydroxide and barium hydroxide to adjust the pH to 9.5, then add acetaldehyde 1.9mol, and heat up to 65-70°C to react, take a sample to detect if there are substances insoluble in alkaline aqueous solution, stop the reaction, and generate phenolic prepolymer;

technical field

[0001] The invention relates to the technical field of phenolic resins, in particular to a preparation method of modified phenolic resins. Background technique

[0002] There are two types of phenolic resins, thermoplastic and thermosetting. Thermoplastic phenolic resin (or called two-step phenolic resin), is a light-colored to dark brown brittle solid, soluble in ethanol, acetone and other solvents, and has long-term solubility. It can be cured only in the presence of cross-linking agent (it can be cured quickly when heated), mainly used in the manufacture of compression molding powder, and also used in the manufacture of laminated plastics, varnishes and adhesives. Thermosetting phenolic resin (or one-step phenolic resin) can be made into solid, liquid and emulsion according to needs, and can be cross-linked and cured without cross-linking agent under the action of heat or (and) acid. In order to guide resin synthesis and molding processing, the curing ...

Examples

Embodiment 1

[0030] The obtained modified phenolic resin is subjected to post-treatment so that the phenol content is 0.8%, and the phosphorus-containing modified phenolic resin is obtained.

[0031] Example 2

[0032] The preparation method of modified phenolic resin comprises the steps:

[0033] (1) Mix 0.4 mol of phenol, 0.3 mol of m-phenol, and 0.3 mol of p-phenol into the reaction vessel, dissolve it in water at a temperature of 55-60 ° C, add barium hydroxide to adjust the pH to 7.5, and then add 1 mol of formaldehyde, Acetaldehyde 0.3mol, and heat up to 75-80°C, react, take a sample to detect if there is a substance insoluble in alkaline aqueous solution, stop the reaction, that is, generate a phenolic prepolymer;

Embodiment 2

[0035] The obtained modified phenolic resin is decompressed to -0.70~-0.60MPa, distilled, dehydrated and dephenolized, the phenol content is less than 0.9%, discharged, and cooled to obtain the desired phosphorus-containing modified phenolic resin.

[0036] Example 3

[0037] The preparation method of phosphorus-containing phenolic resin described in the present embodiment may further comprise the steps:

[0038] (1) Mix m-phenol 0.5mol and p-phenol 0.5mol, heat at 55-60°C to dissolve in water, add ammonium hydroxide to adjust pH to 11, then add formaldehyde 1.2mol, acetaldehyde 0.5mol, and heat up React at 75-80°C, take a sample to detect if there are substances insoluble in alkaline aqueous solution, stop the reaction, and generate a phenolic prepolymer;

Embodiment 3

[0040] The obtained modified phenolic resin is decompressed to -0.70~-0.60MPa, distilled, dehydrated and dephenolized, the phenol content is 0.5%, discharged, and cooled to obtain the desired phosphorus-containing modified phenolic resin.

[0041] Example 4

[0042] The preparation method of phosphorus-containing phenolic resin described in the present embodiment may further comprise the steps:

[0043] (1) Mix 0.4mol o-phenol, 0.4mol m-phenol, and 0.2mol p-phenol and heat at 45-50°C to dissolve in water, add sodium hydroxide and barium hydroxide to adjust the pH to 9.5, then add acetaldehyde 1.9mol, and heat up to 65-70°C to react, take a sample to detect if there are substances insoluble in alkaline aqueous solution, stop the reaction, and generate phenolic prepolymer;

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