阅读说明：本技术 一种发泡树脂的发泡方法 (Foaming method of foaming resin ) 是由 焦正 刘立起 于 2021-01-30 设计创作，主要内容包括：本发明涉及一种发泡树脂的发泡方法,其具体步骤为：将固体甲醛,三聚氰胺,甲醛吸收剂,脱盐水加入到反应釜中进行搅拌反应进行树脂合成；然后加入固化剂,乳化剂以及发泡剂,进行树脂均化；再进行发泡处理,其中发泡产生尾气进行干燥处理,然后再进行等离子处理,发泡后的树脂进行干燥处理,得到发泡树脂。本发明的工艺简单,易于推广。(The invention relates to a foaming method of foaming resin, which comprises the following specific steps: adding solid formaldehyde, melamine, a formaldehyde absorbent and desalted water into a reaction kettle for stirring reaction to synthesize resin; then adding a curing agent, an emulsifier and a foaming agent for resin homogenization; and then carrying out foaming treatment, wherein tail gas generated by foaming is dried, then carrying out plasma treatment, and drying the foamed resin to obtain the foamed resin. The invention has simple process and easy popularization.)

1. The foaming resin is characterized by comprising the following raw materials in parts by weight:

2. the method for foaming a resin foam according to claim 1, comprising the steps of:

adding solid formaldehyde, melamine, a formaldehyde absorbent and desalted water into a reaction kettle for stirring reaction to synthesize resin; then adding a curing agent, an emulsifier and a foaming agent for resin homogenization; and then carrying out foaming treatment, wherein tail gas generated by foaming is dried, then carrying out plasma treatment, and drying the foamed resin to obtain the foamed resin.

3. The method of claim 1, wherein the formaldehyde absorbent is prepared by the following steps: 4, 4, 4-triamino triphenylamine and adipic acid are used as raw materials, N-dimethylacetamide is used as a solvent, phosphoric acid is used as a catalyst, and then the reaction is carried out at 160-190 ℃ in a nitrogen atmosphere; and after the reaction is carried out for 12-20 h, cooling to normal temperature, then adding methanol, filtering the filter residue, and carrying out vacuum drying on the filter residue at 140 ℃ to obtain the required formaldehyde absorbent.

4. The method of claim 1, wherein the emulsifier is 30% dodecyl sulfonate.

5. The method of claim 1, wherein the curing agent is formic acid.

6. The process of claim 1, wherein the blowing agent is n-pentane.

Technical Field

The invention relates to the technical field of resin, in particular to a foaming method of foaming resin.

Background

The foaming resin material has various advantages of excellent impact toughness, high specific rigidity, long fatigue life, low heat conductivity, higher thermal stability, extremely low volume density, excellent flame retardant property and the like, so the foaming resin material has very wide application and can be used for aeronautical industry, railway shipping, automobile manufacturing, information engineering products, medical and health products, interior decoration parts and the like. In the production process of the foaming resin, the foaming process is very important, the quality of the product and the manufacturing cost are directly influenced, and the key point and the difficulty point in the production of the foaming resin are provided.

The invention relates to a method for synthesizing and foaming normal-temperature expandable phenolic resin (application number: 201710447568.1), which comprises the steps of replacing part of phenol raw materials with urea, sequentially adding a catalyst and paraformaldehyde, and carrying out medium-temperature hydroxymethylation reaction and high-temperature polycondensation reaction to obtain the normal-temperature expandable phenolic resin; the resin can complete the foaming and curing process in a normal temperature environment for 3-6 minutes, and the obtained foam is compact and uniform, and has high strength and good toughness. The method of the invention uses urea to replace part of phenol, thus reducing the cost of raw materials, avoiding the need of vacuum dehydration in the reaction, reducing the investment of assets and simplifying the production process.

The Chinese invention patent (application number: 201410614767.3) discloses a gradient foaming method for preparing phenolic foam, which uses a gradient foaming agent to prepare phenolic foam with excellent performance. The gradient foaming agent is a composite organic solvent with multiple boiling points between 25 ℃ and 90 ℃, the boiling points of the organic solvent are distributed in a gradient manner from low to high, the organic solvent has multifunctional components such as foaming, transition, heat absorption and the like, the multifunctional components have different functions in three stages of phenolic resin curing and foaming respectively, the multifunctional components are normally foamed in the early stage of resin curing and foaming, stably foamed in the middle stage and reasonably absorb redundant heat in the later stage, and thus the phenolic foam with excellent performance is prepared. The material of the invention comprises the following components: 4-10 parts of gradient foaming agent, 80-100 parts of resol, 3-7 parts of surfactant and 5-20 parts of curing agent. The phenolic foam prepared by the method has the advantages of uniform density, high section tensile strength, high closed cell rate, complete foam wall, low water absorption and excellent performance. Can be widely used in the high and new technical fields of energy-saving and heat-preserving, fireproof and flame-retardant materials and the like.

The invention discloses a PVA foaming material and a foaming method thereof, and aims to provide the difficulty of the existing continuous extrusion foaming of PVA, the invention utilizes the characteristic of hydrolysis of PVA to foam the PVA in a hydrolysis swelling state at a temperature lower than the boiling point of the PVA. The invention has the beneficial effects that: the microporous expansion foaming agent is added in a swelling state by using water as a medium, and foaming is carried out below the boiling point of PVA, so that not only is PVA gasification avoided, but also extrusion molding is realized, and the operation process is simple; the prepared finished product has light weight (low density), high compressive strength (as high as 259KPa), high degradable components and environmental friendliness.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a foaming method of foaming resin.

The purpose of the invention is realized by the following technical scheme:

a foaming method of foaming resin comprises the following specific steps:

adding solid formaldehyde, melamine, a formaldehyde absorbent and desalted water into a reaction kettle for stirring reaction to synthesize resin; then adding a curing agent, an emulsifier and a foaming agent for resin homogenization; and then carrying out foaming treatment, wherein tail gas generated by foaming is dried, then carrying out plasma treatment, and drying the foamed resin to obtain the foamed resin.

The foaming resin comprises the following raw materials in parts by weight:

the preparation method of the formaldehyde absorbent comprises the following steps: 4, 4, 4-triamino triphenylamine and adipic acid are used as raw materials, N-dimethylacetamide is used as a solvent, phosphoric acid is used as a catalyst, and then the reaction is carried out at 160-190 ℃ in a nitrogen atmosphere; and after the reaction is carried out for 12-20 h, cooling to normal temperature, then adding methanol, filtering the filter residue, and carrying out vacuum drying on the filter residue at 140 ℃ to obtain the required formaldehyde absorbent.

The molar ratio of the 4, 4, 4-triamino triphenylamine to the adipic acid is 1: 0.50.

The mass fraction of the 4, 4, 4-triamino triphenylamine in the N, N-dimethylacetamide solvent is 25%.

The mass fraction of the 4, 4, 4-triamino triphenylamine in the phosphoric acid is 0.5 percent.

The volume ratio of the N, N-dimethylacetamide to the methanol is 1: 0.15.

The emulsifier is 30% of dodecyl sulfonate.

The curing agent is formic acid.

The foaming agent is n-pentane.

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

the method is simple in process and easy to popularize.

Drawings

FIG. 1 reaction equation for preparing formaldehyde absorbent

FIG. 2 shows the hydrogen nuclear magnetic resonance spectrum of formaldehyde absorbent.

Detailed Description

The following provides a specific embodiment of the method for foaming a foamable resin of the present invention.

Example 1

The foaming resin comprises the following raw materials in parts by weight:

the preparation method of the formaldehyde absorbent comprises the following steps: 4, 4, 4-triamino triphenylamine and adipic acid are used as raw materials, N-dimethylacetamide is used as a solvent, phosphoric acid is used as a catalyst, and then the reaction is carried out at 160-190 ℃ in a nitrogen atmosphere; and after the reaction is carried out for 12-20 h, cooling to normal temperature, then adding methanol, filtering the filter residue, and carrying out vacuum drying on the filter residue at 140 ℃ to obtain the required formaldehyde absorbent.

The molar ratio of the 4, 4, 4-triamino triphenylamine to the adipic acid is 1: 0.50.

The mass fraction of the 4, 4, 4-triamino triphenylamine in the N, N-dimethylacetamide solvent is 25%.

The mass fraction of the 4, 4, 4-triamino triphenylamine in the phosphoric acid is 0.5 percent.

The volume ratio of the N, N-dimethylacetamide to the methanol is 1: 0.15.

In the hydrogen nuclear magnetic resonance spectrum of the formaldehyde absorbent, 1 corresponds to an amido bond characteristic absorption peak formed after reaction of adipic acid and 4, 4, 4-triamino triphenylamine, the corresponding chemical shift is 8.01ppm, 2 and 3 correspond to 4, 4, 4-triamino triphenylamine and adipic acid to form a benzene ring structure, the benzene ring structure is influenced by amide functional groups, the splitting condition of the characteristic absorption peak exists, the chemical shifts of 2(7.35ppm) and 3(6.46ppm) on the benzene ring are split, 4 corresponds to a benzene ring characteristic absorption peak which is not reacted on the benzene ring, the chemical shift is 6.21ppm, and the sum of the characteristic peak area of the corresponding 4 chemical shifts and the characteristic peak areas of 2 and 3 is 2: 1, so that the reaction of one amino group on the 4, 4, 4-triamino triphenylamine is also demonstrated, the adipic acid is a bifunctional group structure, so that 4, 4, 4-triamino triphenylamine and adipic acid react according to the molar ratio of 2: 1 to form a small molecular structure; in the atlas, 5 is an unreacted amino characteristic absorption peak, and the ratio of the chemical shift of 5 to the chemical shift of 1 is 2: 1, so that the reaction of 4, 4, 4-triamino triphenylamine and adipic acid according to the molar ratio of 2: 1 is also proved; 6 and 7 correspond to characteristic absorption peaks on the adipic acid structure.

The melamine is easy to generate self-degradation reaction under acidic and neutral conditions, and formaldehyde is generated and released, so that the problem that the formaldehyde content in the existing melamine resin is higher is caused; the formaldehyde and the amino can be subjected to polycondensation reaction under acidic and alkaline conditions, so that the amino functional group with an alkaline structure is introduced in the design process, and the amino in the formaldehyde absorbent and the formaldehyde are subjected to polycondensation reaction by utilizing the alkaline structure of the tertiary amino in the formaldehyde absorbent in humid air, so that the formaldehyde molecules released from the material are fixed and absorbed. Meanwhile, in order to avoid the problems that a small molecular structure is easy to migrate and the reaction activity of 4, 4, 4-triamino triphenylamine is low in a molecular structure, the amide group with a high hydrophilic structure is introduced into the 4, 4, 4-triamino triphenylamine structure, so that the affinity effect of the formaldehyde absorbent and water molecules is improved, and the problems that low-molecular polyamine and moisture hygroscopicity of water are poor and tertiary amine functional groups are difficult to convert into basic structure quaternary ammonium functional groups are solved.

The emulsifier is 30% of dodecyl sulfonate.

The curing agent is formic acid.

The foaming agent is n-pentane.

A foaming method of foaming resin comprises the following specific steps:

adding solid formaldehyde, melamine, a formaldehyde absorbent and desalted water into a reaction kettle for stirring reaction to synthesize resin; then adding a curing agent, an emulsifier and a foaming agent for resin homogenization; and then carrying out foaming treatment, wherein tail gas generated by foaming is dried, then carrying out plasma treatment, and drying the foamed resin to obtain the foamed resin.

Example 2

The foaming resin comprises the following raw materials in parts by weight:

the preparation method of the formaldehyde absorbent comprises the following steps: the same as in example 1.

The emulsifier is 30% of dodecyl sulfonate.

The curing agent is formic acid.

The foaming agent is n-pentane.

A foaming method of foaming resin comprises the following specific steps:

adding solid formaldehyde, melamine, a formaldehyde absorbent and desalted water into a reaction kettle for stirring reaction to synthesize resin; then adding a curing agent, an emulsifier and a foaming agent for resin homogenization; and then carrying out foaming treatment, wherein tail gas generated by foaming is dried, then carrying out plasma treatment, and drying the foamed resin to obtain the foamed resin.

Example 3

The foaming resin comprises the following raw materials in parts by weight:

the preparation method of the formaldehyde absorbent comprises the following steps: the same as in example 1.

The emulsifier is 30% of dodecyl sulfonate.

The curing agent is formic acid.

The foaming agent is n-pentane.

A foaming method of foaming resin comprises the following specific steps:

adding solid formaldehyde, melamine, a formaldehyde absorbent and desalted water into a reaction kettle for stirring reaction to synthesize resin; then adding a curing agent, an emulsifier and a foaming agent for resin homogenization; and then carrying out foaming treatment, wherein tail gas generated by foaming is dried, then carrying out plasma treatment, and drying the foamed resin to obtain the foamed resin.

Example 4

The foaming resin comprises the following raw materials in parts by weight:

the preparation method of the formaldehyde absorbent comprises the following steps: the same as in example 1.

The emulsifier is 30% of dodecyl sulfonate.

The curing agent is formic acid.

The foaming agent is n-pentane.

A foaming method of foaming resin comprises the following specific steps:

adding solid formaldehyde, melamine, a formaldehyde absorbent and desalted water into a reaction kettle for stirring reaction to synthesize resin; then adding a curing agent, an emulsifier and a foaming agent for resin homogenization; and then carrying out foaming treatment, wherein tail gas generated by foaming is dried, then carrying out plasma treatment, and drying the foamed resin to obtain the foamed resin.

Example 5

The foaming resin comprises the following raw materials in parts by weight:

the preparation method of the formaldehyde absorbent comprises the following steps: the same as in example 1.

The emulsifier is 30% of dodecyl sulfonate.

The curing agent is formic acid.

The foaming agent is n-pentane.

A foaming method of foaming resin comprises the following specific steps:

adding solid formaldehyde, melamine, a formaldehyde absorbent and desalted water into a reaction kettle for stirring reaction to synthesize resin; then adding a curing agent, an emulsifier and a foaming agent for resin homogenization; and then carrying out foaming treatment, wherein tail gas generated by foaming is dried, then carrying out plasma treatment, and drying the foamed resin to obtain the foamed resin.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and decorations can be made without departing from the concept of the present invention, and these modifications and decorations should also be regarded as being within the protection scope of the present invention.