阅读说明：本技术 一种发泡用柔性木质素酚醛树脂制备方法 (Preparation method of flexible lignin phenolic resin for foaming ) 是由 时君友 王祺铭 徐文彪 海潇涵 于 2019-10-25 设计创作，主要内容包括：本发明涉及一种发泡用柔性酶解木质素酚醛树脂制备方法。步骤1：苯酚100份、酶解木质素20～40份、工业用甲醛120～130份、氢氧化钠10～20份、月桂胺5～20份、尿素5～15份。步骤2：取苯酚与酶解木质素混合,逐渐升温至95-100℃,体系形成均匀膏状；氢氧化钠调成30％水溶液,将其加入步骤2中,温度保持在90-98℃范围内,至木质素完全溶解,体系呈黑色液态溶液,继续反应1～1.5h；加入月桂胺,继续反应1.5～2.5h；降温至60℃,45分钟内分三次缓慢加入步骤1中所备工业用甲醛；升温至80～90℃,继续反应1～2h,降至60℃；加入所备的尿素,搅拌0.5h后,降至室温,调节pH至中性,脱水20～40份,得本申请柔性木质素酚醛树脂。本申请方法降低生产成本。(The invention relates to a preparation method of flexible enzymatic hydrolysis lignin phenolic resin for foaming. Step 1: 100 parts of phenol, 20-40 parts of enzymolysis lignin, 120-130 parts of industrial formaldehyde, 10-20 parts of sodium hydroxide, 5-20 parts of laurylamine and 5-15 parts of urea. Step 2: mixing phenol and enzymatic hydrolysis lignin, gradually heating to 95-100 ℃, and forming a uniform paste system; preparing 30% aqueous solution from sodium hydroxide, adding the aqueous solution into the step 2, keeping the temperature within the range of 90-98 ℃ until the lignin is completely dissolved and the system is black liquid solution, and continuing to react for 1-1.5 hours; adding laurylamine, and continuing to react for 1.5-2.5 h; cooling to 60 ℃, and slowly adding the industrial formaldehyde prepared in the step 1 into the mixture for three times in 45 minutes; heating to 80-90 ℃, continuously reacting for 1-2 h, and cooling to 60 ℃; adding the prepared urea, stirring for 0.5h, cooling to room temperature, adjusting the pH value to be neutral, and dehydrating by 20-40 parts to obtain the flexible lignin phenolic resin. The method reduces the production cost.)

1. A preparation method of flexible lignin phenolic resin for foaming is characterized by comprising the following steps: the preparation steps are as follows:

1) backup raw materials according to the following mass portions:

2) mixing the phenol prepared in the step 1) with the enzymatic hydrolysis lignin, gradually heating to 95-100 ℃, and forming a uniform paste;

3) preparing the sodium hydroxide prepared in the step 1) into a 30% aqueous solution, adding the aqueous solution into the step 2), keeping the temperature within the range of 90-98 ℃ until the lignin is completely dissolved and the system is a black liquid solution, and continuing to react for 1-1.5 hours;

4) adding the laurylamine prepared in the step 1), and continuously reacting for 1.5-2.5 h;

5) cooling to 60 ℃, slowly adding the industrial formaldehyde prepared in the step 1) into the mixture for three times in 45 minutes;

6) heating to 80-90 ℃, continuously reacting for 1-2 h, and cooling to 60 ℃;

7) adding the urea prepared in the step 1), stirring for 0.5h, cooling to room temperature, adjusting the pH value to be neutral, and dehydrating by 20-40 parts to obtain the flexible lignin phenolic resin.

2. The method for preparing the flexible lignin phenolic resin for foaming according to claim 1, wherein the method comprises the following steps: the optimal mass parts of the raw materials are as follows:

100 parts by mass of phenol, 20 parts by mass of enzymatic hydrolysis lignin, 125 parts by mass of industrial formaldehyde, 15 parts by mass of sodium hydroxide, 10 parts by mass of laurylamine and 5 parts by mass of urea.

Technical Field

The invention relates to the field of phenolic resin preparation, and particularly relates to a preparation method of flexible enzymatic hydrolysis lignin phenolic resin for foaming.

Background

The phenolic resin has a high autoignition temperature of 480 ℃ and thermal stability from-196 ℃ to 200 ℃. It exhibits excellent flame retardancy during combustion and generates only a small amount of toxic gases. In recent years, researches on the preparation of phenolic resin by using lignin to replace phenol are endless, and the substitution rate and the effect of the phenolic resin are greatly increased; with the intensive research on the synthesis of phenolic resin by using lignin, a great deal of research on the use of lignin is carried out on some phenolic material products, such as lignin-based phenolic foam plastics.

Phenolic foam is a new generation of flame retardant, thermal and sound insulation material. Due to its low density, low flammability and low toxicity, it is rapidly developing and widely used in construction, national defense, aviation, energy and other fields. The special properties of phenolic foam make it useful for some highly specialized applications, such as decontamination (nuclear pollution, contaminated water) or the manufacture of space shuttles. The economic potential is huge, and the global insulation market value is billions of Euro. However, phenolic foam has some weakness in mechanical properties, and is also brittle due to the rigidity of the phenolic resin. Much of the research on phenolic foam has focused on modifying its toughness.

Disclosure of Invention

The invention aims to provide a preparation method of flexible enzymatic hydrolysis lignin phenolic resin for foaming, which has the advantages of reducing the production cost of the phenolic resin, reducing the brittleness of foam and increasing the toughness of the foam.

The technical scheme of the invention is as follows:

a preparation method of flexible lignin phenolic resin for foaming comprises the following preparation steps:

1) backup raw materials according to the following mass portions:

2) mixing the phenol prepared in the step 1) with the enzymatic hydrolysis lignin, gradually heating to 95-100 ℃, and forming a uniform paste;

3) preparing the sodium hydroxide prepared in the step 1) into a 30% aqueous solution, adding the aqueous solution into the step 2), keeping the temperature within the range of 90-98 ℃ until the lignin is completely dissolved and the system is a black liquid solution, and continuing to react for 1-1.5 hours;

4) adding the laurylamine prepared in the step 1), and continuously reacting for 1.5-2.5 h;

5) cooling to 60 ℃, slowly adding the industrial formaldehyde prepared in the step 1) into the mixture for three times in 45 minutes;

6) heating to 80-90 ℃, continuously reacting for 1-2 h, and cooling to 60 ℃;

7) adding the urea prepared in the step 1), stirring for 0.5h, cooling to room temperature, adjusting the pH value to be neutral, and dehydrating by 20-40 parts to obtain the flexible lignin phenolic resin.

The invention has the beneficial effects that:

according to the application, the enzymatic hydrolysis lignin with a certain proportion is added to replace phenol when the phenolic resin is prepared, so that the production cost is reduced.

The long-chain fatty monoamine modified lignin phenolic resin is used for the first time, and through the Mannich reaction of laurylamine, lignin, phenol and formaldehyde, a long-chain fatty monoamine is embedded into a molecular chain: laurylamine (laurylamine has 10 rotatable chemical bonds in the molecule and is a flexible molecular chain segment) increases the flexibility of the foam and reduces the brittleness of the foam. The laurylamine is embedded into a system, and a flexible group is introduced, so that the brittleness of the foam is reduced, the toughness of the foam is increased, and the mechanical strength of the foam is improved. The embedded laurylamine molecular chain has both hydrophilic and lipophilic groups, so that the surface activity of the laurylamine molecular chain is increased, the use content of a surfactant is reduced, the cost is reduced, the uniformity of foam is improved, the foaming process is facilitated, and the foam quality is improved.

The flexible enzymatic hydrolysis lignin phenolic foam thermal insulation material product has the advantages of low cost, energy conservation and fire prevention, has low brittleness and high toughness compared with similar products, and can be widely applied to the field of thermal insulation building walls.

Detailed Description

The preparation method of the flexible enzymatic hydrolysis lignin phenolic resin for foaming comprises the following steps:

1) backup raw materials according to the following mass ratio:

2) mixing the phenol prepared in the step 1) with the enzymatic hydrolysis lignin, gradually heating to 95 ℃, and forming a uniform paste system.

3) Adding sodium hydroxide (prepared into a 30% aqueous solution) prepared in the step 1), keeping the temperature within the range of 90-98 ℃ until the lignin is completely dissolved and the system is a black liquid solution, and continuing to react for 1-1.5 h.

4) Adding the laurylamine (dodecylamine, fatty monoamines) prepared in the step 1) and continuously reacting for 1.5-2.5 h. Laurylamine (dodecylamine) is a modifier, is a flexible segment of long-chain fatty monoamine, and can represent a long-chain fatty monoamine compound.

5) Cooling to 60 ℃, and slowly adding the formaldehyde prepared in the step 1) into the mixture in three times in 45 minutes.

6) Heating to 80-90 ℃, and continuing to react for 1-2 h. The temperature is reduced to 60 ℃.

7) Adding a certain amount of urea, stirring for 0.5h, cooling to room temperature, adjusting the pH value to be neutral, and dehydrating by 20-40 parts to obtain the flexible lignin phenolic resin.

Mixing 100 parts of the flexible lignin phenolic resin obtained in the step 7) with 3-6 parts of an organic silicon foam stabilizer, 6-10 parts of a foaming agent n-amyl hospital and one or more of a curing agent p-toluenesulfonic acid, benzenesulfonic acid, phosphoric acid and sulfuric acid, dissolving in 0.4-0.5 part of water, uniformly stirring, injecting into a preset mold, foaming by using a conventional method, wherein the foaming density range is 30-70 kg/m³And obtaining the phenolic acyl foam wall thermal insulation material product of the invention. The curing agent is a composite curing agent which is one or more of p-toluenesulfonic acid, benzenesulfonic acid, phosphoric acid and sulfuric acid dissolved in 0.4-0.5 parts of water.

Example 1

A preparation method of flexible enzymatic hydrolysis lignin phenolic resin for foaming comprises the following steps:

(1) backup of raw materials: 100 parts by mass of phenol, 20 parts by mass of enzymatic hydrolysis lignin, 125 parts by mass of industrial formaldehyde, 15 parts by mass of sodium hydroxide (prepared into a 30% mass fraction aqueous solution), 10 parts by mass of laurylamine and 5 parts by mass of urea.

(2) And (2) adding the phenol and the enzymatic hydrolysis lignin obtained in the step (1) into a reaction kettle, slowly heating to 95 ℃, starting a stirrer, and slowly stirring to form uniform turbid liquid.

(3) Adding 30 mass percent of prepared sodium hydroxide solution into the reaction kettle, quickly stirring, and reacting for 1 hour at 95 ℃.

(4) Adding the laurylamine obtained in the step (1) into a reaction kettle, and stirring and reacting for 2 hours at 95 ℃.

(5) And (3) cooling the system to 60 ℃, and slowly adding the formaldehyde in the step (1) into the reaction kettle for three times in 45 minutes.

(6) Heating the system to 85-90 ℃, continuing to react for 1-1.5 hours, and then cooling to 60 ℃.

(7) And (2) adding the urea in the step (1), cooling to room temperature, stirring for 30 minutes, and adjusting the pH value to be neutral. And (5) dehydrating by 20-25 parts by mass to obtain the flexible enzymatic hydrolysis lignin phenolic resin.

(8) Sequentially taking 100 parts by mass of the flexible lignin phenolic resin obtained in the step 7), 3 parts by mass of an organic silicon foam stabilizer, 8 parts by mass of a foaming agent n-amyl ketone and a composite curing agent (according to the mass ratio of p-toluenesulfonic acid: phosphoric acid: water 6: 4: 2 proportion mixing) 16 mass fractions are evenly stirred and then injected into a preset mould to be foamed by a conventional method, wherein the foaming density is 40-50 kg/m³And obtaining the flexible enzymatic hydrolysis lignin phenolic foam product of the invention.

Example 2

A preparation method of flexible enzymatic hydrolysis lignin phenolic resin for foaming comprises the following steps:

(1) backup of raw materials: 200 parts by mass of phenol, 50 parts by mass of enzymatic hydrolysis lignin, 260 parts by mass of industrial formaldehyde, 30 parts by mass of sodium hydroxide (prepared into a 30% mass fraction aqueous solution), 30 parts by mass of laurylamine and 10 parts by mass of urea.

(2) And (2) adding the phenol and the enzymatic hydrolysis lignin obtained in the step (1) into a reaction kettle, slowly heating to 98 ℃, starting a stirrer, and slowly stirring to form uniform turbid liquid.

(3) Adding 30 mass percent of prepared sodium hydroxide solution into the reaction kettle, quickly stirring, and reacting at 95 ℃ for 1.2 hours, wherein the enzymatic hydrolysis lignin is completely dissolved.

(4) Adding the laurylamine obtained in the step (1) into a reaction kettle, and stirring and reacting at 95 ℃ for 2.5 hours.

(5) And (3) cooling the system to 60 ℃, and slowly adding the formaldehyde in the step (1) into the reaction kettle for three times in 45 minutes.

(6) Heating the system to 80-85 ℃, continuing to react for 1.5-2 hours, and then cooling to 60 ℃.

(7) And (2) adding the urea in the step (1), cooling to room temperature, stirring for 30 minutes, and adjusting the pH value to be neutral. And 25-30 parts by mass of dehydration. Obtaining the flexible enzymatic hydrolysis lignin phenolic resin.

(8) Sequentially taking 100 parts by mass of the flexible lignin phenolic resin obtained in the step 7), 4 parts by mass of an organic silicon foam stabilizer, 10 parts by mass of a foaming agent n-amyl ketone and a composite curing agent (according to the mass ratio of p-toluenesulfonic acid: phosphoric acid: water 6: 4: 2 proportion mixing) 18 mass fractions are evenly stirred and then injected into a preset mould to be foamed by a conventional method, wherein the foaming density is 40-55 kg/m³And obtaining the flexible enzymatic hydrolysis lignin phenolic foam product of the invention.

Example 3

A preparation method of flexible enzymatic hydrolysis lignin phenolic resin for foaming comprises the following steps:

(1) backup of raw materials: 100 parts by mass of phenol, 25 parts by mass of enzymatic hydrolysis lignin, 130 parts by mass of industrial formaldehyde, 15 parts by mass of sodium hydroxide (prepared into a 30% mass fraction aqueous solution), 20 parts by mass of laurylamine and 8 parts by mass of urea.

(2) And (2) adding the phenol, the enzymatic hydrolysis lignin and 30 mass percent of prepared sodium hydroxide solution in the step (1) into a reaction kettle, slowly heating to 100 ℃, starting a stirrer, and slowly stirring.

(3) Stirring for 1 hour at about 95 ℃ until the enzymatic hydrolysis lignin is completely liquefied.

(4) Adding the laurylamine obtained in the step (1) into a reaction kettle, and stirring and reacting for 2 hours at 95 ℃.

(5) And (3) cooling the system to 60 ℃, slowly adding the formaldehyde in the step (1) into the reaction kettle for three times in 45 minutes, and quickly stirring.

(6) Heating the system to 85-90 ℃, continuing to react for 1-1.5 hours, and then cooling to 60 ℃.

(7) And (2) adding the urea in the step (1), cooling to room temperature, stirring for 30 minutes, and adjusting the pH value to be neutral. And (3) dehydrating by 30-35 parts by mass to obtain the flexible enzymatic hydrolysis lignin phenolic resin.

(8) Sequentially taking 100 parts by mass of the flexible lignin phenolic resin obtained in the step 7), 3 parts by mass of an organic silicon foam stabilizer, 8 parts by mass of a foaming agent n-amyl ketone and a composite curing agent (according to the mass ratio of p-toluenesulfonic acid: phosphoric acid: water 5: 5: 2 proportion mixing) 16 mass fractions are evenly stirred and then injected into a preset die, and the mixture is foamed by a conventional method, wherein the foaming density range is 30-70 kg/m3, and the flexible enzymatic hydrolysis lignin phenolic foam product is obtained.