WO2020041954A1 - Novel and environmentally-friendly process for preparing resorcinol formaldehyde resin with high adhesive strength - Google Patents

Abstract

Disclosed is a process for preparing a resorcinol formaldehyde resin with a high adhesive strength. The process comprises preparing a resin by using resorcinol and formaldehyde as raw materials and ethylvinyl benzene as a modifying agent under the action of a composite acidic catalyst, and the process steps are S1: a melting treatment; S2: an addition-condensation reaction; S3: a neutralizing treatment; S4: distillation; and S5: pelleting, wherein the weight ratio of formaldehyde : resorcinol : ethylvinyl benzene : the composite acidic catalyst is ensured to be 20-30 : 55-65 : 25-30 : 3-5 during the addition-condensation reaction, the ratio reduces the amount of free resorcinol, and the composite acidic catalyst has a high acid strength and a high catalytic activity.

Description

Novel green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength Technical field

The invention relates to the technical field of engineering materials, in particular to a novel green environmental protection process for preparing a resorcinol formaldehyde resin with high adhesive strength.

Background technique

According to the literature, in the rubber product industry, bonding refers to the contact between rubber and the surface of homogeneous or heterogeneous materials. The combination of the physical effect of van der Waals force or the chemical action of bonding force will directly affect the use of rubber products. Lifetime, usually, the material that can combine the adjacent surfaces of a material is called an adhesive, which has excellent elasticity and is suitable for bonding soft or materials with very different thermal expansion coefficients, such as rubber and rubber, rubber and metal, plastic , Leather, wood and other materials. Rubber adhesive is a mixture of highly active organic amine compounds and inorganic compounds containing a large number of reactive groups. Steel cords or limiting cords are often used to strengthen the strength of rubber products. It produces strong chemical bonding, improves the bonding strength, and improves the rubber coverage of the cord. It has a wide range of applications in aircraft manufacturing, automobile manufacturing, construction, light industry, and rubber product processing.

In the prior art, in the process of bonding different rubber products, it is easy to cause phenomena such as inadequate bonding and easy loosening, and product quality will be affected. Resorcinol monomer is usually used as the methylene acceptor binding material, but because of the lower smoke point of resorcinol, it is released during the mixing process (150 ℃ ～ 200 ℃) and harmful to health. The substance, therefore, is gradually being replaced by a pre-shrinked resorcinol-formaldehyde resin. The resorcinol formaldehyde resin prepared by the reaction of resorcinol and formaldehyde solution can form a network structure that can improve the physical properties, mechanical properties and adhesive properties of vulcanized rubber. After forming an adhesive layer, it can work with rubber compounds and steel wires. The adhesive layer plays a good role in connection and transition, and is a raw material widely used in the chemical industry such as tires and adhesives.

When modified in most scenarios, it is easy to reduce the reactive sites of resorcinol, so that the function of the resin as a methylene acceptor is affected to a certain extent, and the resorcinol is freed from the resin during the preparation process. The content is increased, the reaction is not complete, the extension performance of the resin is poor, and the adhesion performance and fatigue bending resistance are not ideal.

Summary of the Invention

In view of the above problems, the present invention provides a novel green environmental protection process for preparing a resorcinol formaldehyde resin with high adhesive strength.

The technical scheme of the present invention: a novel green environmental protection process for preparing a resorcinol formaldehyde resin with high adhesive strength, including the following steps:

S1: Melt treatment

Under the protection of an inert gas, 60-78g of resorcinol was added to deionized water at 0.4 to 1.3 times the total mass of resorcinol, and the pressure was 0.3-0.9Mpa and the temperature was 80-110 ° C. Stirring treatment, stirring time is 1-1.3h, stop stirring after stirring, heat preservation treatment for 35-70min, then adjust the pressure to normal pressure, and evaporate and condense to 35-55% of the original volume under normal temperature conditions, maintaining the flow rate of inert gas 15-25ml / min, purify and dissolve resorcinol, ensure the uniformity of dispersion during heating and melting, and facilitate heating and melting. The evaporative and concentrated liquid is heated and melted in stages. The first stage control temperature is 60-85. ℃, the pressure is 0.4-0.6MPa, the treatment time is 18-25min, then the exhaust treatment is performed to reduce the pressure to 0.3Mpa, after the treatment is completed, the temperature is maintained for 15min, the second stage control temperature is 85-125 ℃, and the temperature is 100-120 ℃ When the pressure is increased to 0.7-0.9Mpa, the processing time is 35-50min, and the temperature is maintained for 25min after the treatment is completed. The third stage control temperature is 125-135 ° C, the pressure is normal pressure, and the processing time is 43-65min. Incubate for 30min. Stirring treatment is completed under wave heating environment, and heating and melting treatment is completed. Temperature and pressure are adjusted through three stages, which can ensure that when resorcinol melts into a liquid, it improves processing performance and toughness, while reducing water absorption and performing condensation. Enhance the adhesion and stability of the polymer during the reaction;

S2: Addition condensation reaction

After completing the heating and melting in S1, keep the temperature constant, control the pressure to 0.2-0.4Mpa, first add the composite acid catalyst, the stirring speed is 600-750r / min, the processing time is 35-40min, cool to room temperature, and then Ethylvinylbenzene is added dropwise at a drop rate of -2ml / min. After each dropwise addition for 60s, the dropwise addition is repeated every 50s until the addition is completed. The temperature is controlled at 125-135 ° C. When the temperature is 130-135 At ℃, the pressure is adjusted to 0.6MPa, and the control time is 20-30 minutes. The dropping process continuously uses ultrasonic waves at 20-33Hz for dispersion treatment. When the dropping is completed, the pressure is adjusted to normal pressure and the temperature is 130-140 ° C. Incubate the reaction for 50-60min, and then perform the condensation reaction. During this time, formaldehyde is added dropwise, using microwave heating, the stirring speed is 550-700r / min, and the temperature is raised at 15-20 ° C per minute to control the temperature at 85-93 ° C. , The holding time is 35-50min;

S3: neutralization processing

Add a neutralizing agent to S2 to perform a neutralization treatment with a magnetic bar stirring, and adjust the pH to 7;

S4: Distillation

Atmospheric distillation treatment by hot air bath, heating to boiling state within 20-25min, maintaining the state for 25min, stirring by centrifugation speed 900-1000r / min, standing still, decompression during reflux Distillation, sampling to measure the softening point, control the temperature between 85-107 ℃, if it can not reach 85 ℃ should still extend the vacuum time, and obtain the resin by vacuum distillation;

S5: Granulation

Turn on the granulator, turn on the pump, and adjust the rotation speed until the granules formed are semi-circular without tailing, which means that the granulation is successfully bagged.

Further, in step S1, the inert gas is composed of helium and argon. Before the resorcinol is added, in a dry inert gas atmosphere, the temperature is 60-110 ° C, and the gas is passed in at a gas flow rate of 0.1-2L / min. Deionized water is heated for 10-15 minutes. When resorcinol is added, the heated solution is refluxed under an inert gas dried at room temperature. The reflux time is 25-40 minutes to obtain The resorcinol solution is protected by an inert gas to prevent oxidative discoloration in the air and affect the melting treatment of resorcinol.

Further, the weight ratio of formaldehyde: resorcinol: ethylvinylbenzene: complex acid catalyst in step S2 is 20-30: 55-65: 25-30: 3-5, and the ratio can be better performed. Addition condensation reaction reduces free resorcinol.

Further, according to the mass percentage of the composite acid catalyst in step S3: 35-60% toluenesulfonic acid, 20-35% maleic acid, and the balance is methylmalonic acid. , Toluenesulfonic acid, maleic acid are sequentially mixed with water to obtain their respective saturated solutions. The three saturated solutions are mixed and heated to 60-80 ° C by microwave for magnetic bar stirring treatment. The stirred mixed solution is then mixed. Under the vacuum of 0.4-0.6KPa, according to the mass ratio of the mixed solution and the porous support aluminum silicate of 3: 2, add the porous support aluminum silicate, leave it for 12-16 hours, and perform it at a low temperature of 5-6 ° C. Dry and roast to obtain the early composite acid catalyst, and then cool the composite acid catalyst through quick freezing, the quick freezing temperature is -12 to -15 ° C, the quick freezing time is 10 to 16 minutes, the standing treatment at room temperature is performed, and the compound is broken after 20-30 meshes. An acidic catalyst. The composite acidic catalyst prepared by this ratio can reduce free resorcinol, has high acid strength, high catalytic activity, improves condensation efficiency, and can improve properties such as toughness and viscosity of the product.

Further, the neutralizing agent in step S3 is based on a weight percentage of 30-60% sodium hydroxide, 15-20% monoethanol diisopropanolamine, and the balance is lauryl diethanolamine. The blending agent can adjust the pH value to 7 and has good volatility, which can improve the viscosity and curing degree of the resin and ensure the stability of the resin granulation.

Further, when the vacuum distillation is performed in step S4, the vacuum degree is controlled to be ≧ 0.08Mpa, and the temperature is 170 ± 10 ° C.

Further, in step S5, the resin is firstly subjected to ultrasonic dispersion treatment, and then the processed resin is atomized and sprayed in a pulse manner, the rotation speed is adjusted to 1200-1600rpm, and the granulation treatment is performed, and then the ultrasonic dispersion treatment is performed first, and the processing time is It is 10-15min to ensure the uniform dispersion inside the resin. At the same time, the resin is atomized and sprayed by means of pulse to ensure the dispersion after entering the granulator. The granules formed are semi-circular without tailing.

Further, before performing the neutralization treatment in step S3, the neutralizing agent is first heated in a water bath to 65-75 ° C, and the neutralizing agent is added at intervals of 5 minutes. During the period, the material is passed through the condensation reaction resin at a temperature of 5-9 ° C. Blow evaporation, adjust the pH value, improve the efficiency of the neutralizer, at the same time ensure the volatility of the material moisture, and enhance the stability of the resin.

Compared with the prior art, the present invention has the beneficial effects that the preparation process of the present invention is perfect, the preparation time is short, and the resorcinol is melt-treated to change the crystalline phase into a liquid phase and subjected to purification treatment. Prevent oxidative discoloration under gas protection, and then process at three different temperatures and pressures in three stages to improve stability in the liquid phase, improve processability and toughness, reduce water absorption, less smoke, and enhance during condensation reactions The adhesion and stability of the polymer, the addition of a composite acid catalyst can make the resin have larger molecules, have a certain spatial structure and mechanical properties, and can be easily washed out of the resin. The modifier can be guaranteed by ultrasonic and dropwise addition. With the composite acid catalyst, the aralkylation reaction occurs during the condensation reaction, which improves the stability, improves the tensile strength, abrasion resistance, tearing performance and dynamic performance, has strong temperature adaptability, maintains high adhesive strength, and reacts. Short cycle, high production efficiency, should not be agglomerated.

detailed description

In order to facilitate the understanding of the technical solution of the present invention, the present invention is further explained according to specific embodiments, and the embodiments do not constitute a limitation on the protection scope of the present invention.

Example 1

A new green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength, including the following steps:

S1: Melt treatment

The inert gas is composed of helium and argon at a volume ratio of 2: 3. Before the resorcinol is added, it is passed in a dry inert gas atmosphere at a temperature of 60 ° C and a gas flow rate of 0.1 L / min. Deionized water is heated in ionized water for 10-15 minutes. When resorcinol is added, 60 g of resorcinol is added to deionized water which is 0.4 times the total mass of resorcinol, and dried at room temperature. The heated solution is refluxed under an inert gas. The reflux time is 25-40min to obtain a resorcinol solution. The solution is stirred at a pressure of 0.3Mpa and a temperature of 80 ° C. The stirring time is 1h. After completion of the stirring, stop the heat preservation treatment for 35min, and then adjust the pressure to normal pressure. Under normal temperature conditions, evaporate and condense to 35% of the original volume, maintain the inert gas flow rate of 15ml / min, and heat and melt the liquid after evaporation and concentration. The first stage control temperature is 60 ℃, the pressure is 0.4MPa, and the treatment time is 18-25min. After exhaust treatment, the pressure is reduced to 0.3Mpa, after the treatment is completed, the temperature is maintained for 15min. The second stage control temperature is 85 ℃, and the pressure is adjusted. 0.7Mpa, treatment time is 35min, heat preservation is 25min after the completion of the treatment, the third stage control temperature is 125 ℃, the pressure is normal pressure, the treatment time is 43min, the heat preservation is 30min after the treatment is completed, and the microwave heating is performed in all three stages. Stirring treatment, complete heating and melting treatment;

S2: Addition condensation reaction

After heating and melting in S1, keep the temperature constant and control the pressure to 0.2Mpa. Among them, the weight ratio of formaldehyde: resorcinol: ethylvinylbenzene: composite acid catalyst is 20: 55: 25: 3. First add a composite acid catalyst. The composite acid catalyst is based on mass percentage: 35% toluenesulfonic acid, 20% maleic acid, and the balance is methylmalonic acid. According to the preparation process, methylmalonic acid and toluenesulfonic acid are used. 1. Maleic acid is sequentially mixed with water to obtain respective saturated solutions. Three saturated solutions are mixed and heated by microwave to 60 ° C. for magnetic bar stirring treatment. The stirred mixed solution is vacuumed at 0.4 KPa. According to the mass ratio of the mixed solution and the porous carrier aluminum silicate of 3: 2, the porous carrier aluminum silicate was added, left to stand for 12 hours, and dried at a low temperature of 5 ° C., and then calcined to obtain a composite acid catalyst at an early stage. The catalyst is cooled by quick freezing, with a quick freezing temperature of -12 ° C, a quick freezing time of 10 minutes, and standing treatment at room temperature to perform a composite acid catalyst that has been broken through 20 meshes. The stirring speed is 600 r / min and the processing time is 35 minutes. After cooling to room temperature, ethyl vinylbenzene was added dropwise at a dropping rate of 1 ml / min. After each dropwise addition for 60 s, the dropwise addition was repeated every 50 s until the addition was completed. The temperature was controlled at 125 ° C. When the temperature was At 130 ° C, adjust the pressure to 0.6MPa and control time for 20 minutes. During the dropwise addition, the dispersion is continuously treated with ultrasonic waves at 20Hz. After the dropwise addition is completed, adjust the pressure to normal pressure, adjust the temperature to 130 ° C, and perform a heat preservation reaction for 50min. Then, a condensation reaction is performed, during which formaldehyde is continuously added dropwise, using microwave heating, the stirring speed is 550r / min, and the heating treatment is performed at 15 ° C per minute to control the temperature at 85 ° C and the holding time to 35min;

S3: neutralization processing

Add a neutralizer in S2. The weight of the neutralizer is 30% sodium hydroxide, 15% monoethanol diisopropanolamine, and the balance is lauroyl diethanolamine. Before neutralization, neutralize The agent is heated in a water bath to 65 ° C, and the neutralizing agent is added at intervals of 5 minutes. During the period, the material is subjected to air blowing and evaporation at a temperature of 5 ° C, the pH value is adjusted, and the neutralization treatment is performed by stirring with a magnetic bar. pH value is 7;

S4: Distillation

Atmospheric distillation treatment by hot air bath, heating up to boiling state within 20min, keeping the state for 25min, stirring by centrifugation speed of 900r / min, standing still, start decompression distillation during decompression, decompression The vacuum degree during distillation is controlled to ≥0.08Mpa, the temperature is 160 ° C, the softening point is sampled, and the control temperature is between 85 ° C. If it cannot reach 85 ° C, the vacuum time should be extended, and the resin can be obtained by vacuum distillation;

S5: Granulation

First, the resin is subjected to ultrasonic dispersion treatment for a processing time of 10 minutes, and then the processed resin is atomized and sprayed into the granulator by means of pulse. Turn on the granulator, turn on the material pump, and adjust the rotation speed to 1200 rpm. , Until the granules formed are semi-circular without tailing, the bagging is successfully performed for granulation.

Example 2

A new green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength, including the following steps:

S1: Melt treatment

The inert gas is composed of helium and argon in a volume ratio of 2: 3. Before the resorcinol is added, it is passed in a dry inert gas atmosphere at a temperature of 80 ° C and a gas flow rate of 1.5 L / min. Deionized water was heated in ionized water for 13 minutes. When resorcinol was added, 72 g of resorcinol was added to deionized water which was 0.8 times the total mass of resorcinol. The inert gas was dried at room temperature. The heated solution is then subjected to reflux treatment, the reflux time is 25-40min to obtain a resorcinol solution, and the stirring treatment is performed at a pressure of 0.7Mpa and a temperature of 100 ° C, the stirring time is 1.2h, and the stirring is completed After that, the stirring was stopped, the heat preservation treatment was performed for 65 minutes, and the pressure was adjusted to normal pressure. Evaporation and concentration were performed to 45% of the original volume under normal temperature conditions. The flow rate of the inert gas was maintained at 20 ml / min. The first stage control temperature is 70 ° C, the pressure is 0.5MPa, the treatment time is 20min, and the exhaust pressure is reduced to 0.3Mpa. After the treatment is completed, the temperature is maintained for 15min. The second stage control temperature is 100 ° C, and the pressure is adjusted to 0. .8Mpa, treatment time is 45min, heat preservation is 25min after the completion of the treatment, the third stage control temperature is 130 ° C, the pressure is normal pressure, the treatment time is 50min, the heat preservation is 30min after the treatment is completed, and the microwave heating is performed in all three stages. Stirring treatment, complete heating and melting treatment;

S2: Addition condensation reaction

After heating and melting in S1, keep the temperature unchanged and control the pressure to 0.3Mpa. Among them, the weight ratio of formaldehyde: resorcinol: ethylvinylbenzene: composite acid catalyst is 25: 60: 27: 4. First add a composite acid catalyst. The composite acid catalyst is based on mass percentage of 45% toluenesulfonic acid, 30% maleic acid, and the balance is methylmalonic acid. During the preparation process, according to methylmalonic acid and toluenesulfonic acid, 1. Maleic acid is sequentially mixed with water to obtain respective saturated solutions. Three saturated solutions are mixed and heated to 70 ° C by microwave to perform magnetic bar stirring. The stirred mixed solution is vacuumed at 0.5KPa. According to the mass ratio of the mixed solution and the porous carrier aluminum silicate of 3: 2, the porous carrier aluminum silicate was added, left to stand for 13 hours, dried at a low temperature of 5 ° C, and calcined to obtain a preliminary composite acid catalyst. The acid line catalyst is cooled by quick freezing, with a quick freezing temperature of -13 ° C, a quick freezing time of 13 minutes, and standing treatment at room temperature to perform a composite acid catalyst that has been broken through 25 meshes. The stirring speed is 650 r / min and the processing time is 38 mi. n, cool to room temperature, and then add ethyl vinylbenzene at a drop rate of 1.5ml / min. After each drop is added for 60s, the dropwise addition is repeated every 50s until the addition is complete. The temperature is controlled at 130 ° C. When the temperature is 133 ° C, adjust the pressure to 0.6 MPa, and the control time is 25 minutes. During the dropwise addition, the ultrasonic wave is continuously used for dispersion treatment at 25Hz. After the dropwise addition is completed, adjust the pressure to normal pressure and adjust the temperature to 135 ° C. Incubation reaction for 55min, and then condensation reaction, during which formaldehyde is continuously added dropwise, using microwave heating, stirring speed is 650r / min, heating treatment is performed at 18 ° C per minute, the temperature is controlled at 89 ° C, and the incubation time is 40min;

S3: neutralization processing

Add a neutralizer in S2. The weight of the neutralizer is 50% sodium hydroxide, 18% monoethanol diisopropanolamine, and the balance is lauroyl diethanolamine. Before neutralization, neutralize The agent is heated in a water bath to 70 ° C, and the neutralizing agent is added at intervals of 5 minutes. During the period, the resin is subjected to wind blowing and evaporation at a temperature of 7 ° C, and the pH is adjusted. The magnetic rod is used for neutralization to adjust the pH. Value is 7;

S4: Distillation

Atmospheric distillation treatment with hot air bath, heating to boiling state within 23min, maintaining the state for 25min, stirring by centrifugation speed of 950r / min, standing still, starting decompression distillation during decompression, decompression The vacuum degree during distillation is controlled to ≥0.08Mpa, the temperature is 170 ° C, the softening point is sampled, and the control temperature is between 95 ° C. If it cannot reach 85 ° C, the vacuum time should be extended, and the resin can be obtained by vacuum distillation;

S5: Granulation

First, the resin is subjected to ultrasonic dispersion treatment for a processing time of 13 minutes, and then the processed resin is atomized and sprayed into the granulator by means of pulse. Turn on the granulator, turn on the material pump, adjust the rotation speed, and adjust the rotation speed to 1400 rpm. , Until the granules formed are semi-circular without tailing, the bagging is successfully performed for granulation.

Example 3

A new green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength, including the following steps:

S1: Melt treatment

The inert gas is composed of helium and argon in a volume ratio of 2: 3. Before the resorcinol is added, under a dry inert gas atmosphere, the temperature is 110 ° C, and deionized gas is introduced at a gas flow rate of 2L / min. In water, heat deionized water for 15 minutes. When resorcinol is added, add 78 g of resorcinol to deionized water that is 1.3 times the total mass of resorcinol. Dry under inert gas at room temperature. The heated solution was further subjected to reflux treatment. The reflux time was 40 minutes to obtain a resorcinol solution. The solution was stirred at a pressure of 0.9 MPa and a temperature of 110 ° C. The stirring time was 1.3 hours. After the stirring was completed, the stirring was stopped. , Heat preservation treatment for 70min, and then adjust the pressure to normal pressure, evaporate and condense to 55% of the original volume under normal temperature conditions, maintain the inert gas flow rate of 25ml / min, and heat and melt the liquid after the evaporation and concentration in stages, the first stage of control The temperature is 85 ° C, the pressure is 0.6MPa, the treatment time is 25min, and the pressure is reduced to 0.3Mpa. After the treatment is completed, the temperature is maintained for 15min. The second stage control temperature is 125 ° C, and the pressure is adjusted to 0.9Mp. a, the processing time is 50min, the temperature is maintained for 25min after the completion of the treatment, the third stage control temperature is 135 ° C, the pressure is normal pressure, the processing time is 65min, the temperature is maintained for 30min after the treatment is completed, and the stirring is performed in a microwave heating environment in all three stages Processing, complete heating and melting treatment;

S2: Addition condensation reaction

After heating and melting in S1, keep the temperature unchanged and control the pressure to 0.4Mpa. Among them, the weight ratio of formaldehyde: resorcinol: ethylvinylbenzene: complex acid catalyst is 30: 65: 30: 5. First add the composite acid catalyst. The composite acid catalyst is based on mass percentage of 60% toluenesulfonic acid, 35% maleic acid, and the balance is methylmalonic acid. During the preparation process, methylmalonic acid and toluenesulfonic acid are used. 1. Maleic acid is sequentially mixed with water to obtain respective saturated solutions. Three saturated solutions are mixed and heated to 80 ° C by microwave to perform magnetic bar stirring treatment. The stirred mixed solution is vacuumed at 0.6KPa. According to the mass ratio of the mixed solution and the porous carrier aluminum silicate of 3: 2, the porous carrier aluminum silicate was added, left for 16 hours, dried at a low temperature of 6 ° C, and calcined to obtain a pre-phase composite acid catalyst. The acid line catalyst is cooled by quick freezing, the quick freezing temperature is -15 ° C, the quick freezing time is 16 minutes, and it is left to stand at room temperature to perform a composite acid catalyst that has been broken through 30 meshes. The stirring speed is 750 r / min and the processing time is 40 mi. n, cool to room temperature, and then add ethyl vinylbenzene at a drop rate of 2ml / min. After each drop is added for 60s, the dropwise addition is repeated every 50s until the addition is complete. The temperature is controlled at 135 ° C. When the temperature is 135 ° C, adjust the pressure to 0.6MPa, and the control time is 30 minutes. During the dropwise addition process, ultrasonic waves are continuously used for dispersion treatment at 33Hz. After the dropwise addition is completed, the pressure is adjusted to normal pressure, the temperature is adjusted to 140 ° C, and the temperature is maintained. The reaction is carried out for 60 minutes, and then a condensation reaction is performed, during which formaldehyde is continuously added dropwise, using microwave heating, the stirring speed is 700 r / min, and the heating treatment is performed at 20 ° C per minute to control the temperature to 93 ° C and the holding time to 50min;

S3: neutralization processing

Add a neutralizer in S2. The weight of the neutralizer is 60% sodium hydroxide, 20% monoethanol diisopropanolamine, and the balance is lauroyl diethanolamine. Before neutralization, neutralize The agent is heated in a water bath to 75 ° C, and the neutralizer is added at intervals of 5 minutes. During the period, the resin is subjected to air blowing and evaporation at a temperature of 9 ° C, the pH value is adjusted, and the neutralization treatment is performed by stirring with a magnetic bar. pH value is 7;

S4: Distillation

Atmospheric distillation treatment by hot air bath, heating to boiling state within 25min, keeping the state for 25min, stirring by centrifugation speed of 1000r / min, standing still, starting decompression distillation during decompression, decompression The vacuum degree during distillation is controlled to ≥0.08Mpa, the temperature is 180 ° C, and the softening point is sampled to control the temperature between 107 ° C. If the temperature cannot reach 85 ° C, the vacuum time should be extended, and the resin can be obtained by vacuum distillation;

S5: Granulation

First, the resin is subjected to ultrasonic dispersion treatment for a processing time of 15 minutes, and then the processed resin is atomized and sprayed into the granulator by means of pulse. Turn on the granulator, turn on the material pump, adjust the rotation speed, and adjust the rotation speed to 1600 rpm. , Until the granules formed are semi-circular without tailing, the bagging is successfully performed for granulation.

After inspection, the content of free resorcinol in the resorcinol formaldehyde resin rubber adhesive is less than 3.5%, and the density of the resorcinol formaldehyde resin rubber adhesive is 1.300 g / cm ^{3 The} product is qualified.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than limiting it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that it can still Modifications to the technical solutions described in the foregoing embodiments, or equivalent replacements of some of the technical features thereof; and these modifications or replacements do not depart the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (8)

1. The new green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength is characterized in that it includes the following steps:

   S1: Melt treatment

   Add resorcinol to deionized water at 0.4 to 1.3 times the total mass of resorcinol under the protection of an inert gas, and perform stirring treatment at a pressure of 0.3-0.9Mpa and a temperature of 80-110 ° C. Stirring time is 1-1.3h. After stirring is complete, stop stirring, heat preservation for 35-70min, then adjust the pressure to normal pressure, evaporate and condense to 35-55% of the original volume under normal temperature conditions, and maintain an inert gas flow rate of 15-25ml / min, the liquid after evaporation and concentration is heated and melted in stages. The first stage is controlled at a temperature of 60-85 ° C, a pressure of 0.4-0.6MPa, and a treatment time of 18-25min. After exhaust treatment, the pressure is reduced to 0.3Mpa. After the treatment is completed, the temperature is maintained for 15 minutes, the second stage is controlled at a temperature of 85-125 ° C, the pressure is adjusted to 0.7-0.9Mpa, the processing time is 35-50min, the temperature is maintained for 25 minutes after the treatment is completed, and the third stage is controlled at 125-135 ° C The pressure is normal pressure, the processing time is 43-65min, and the temperature is maintained for 30min after the treatment is completed. The stirring treatment is performed in a microwave heating environment in three stages to complete the heating and melting treatment;

   S2: Addition condensation reaction

   After completing the heating and melting in S1, keep the temperature constant, control the pressure to 0.2-0.4Mpa, first add the composite acid catalyst, the stirring speed is 600-750r / min, the processing time is 35-40min, cool to room temperature, and then Ethyl vinylbenzene is added dropwise at a drop rate of -2ml / min. After each dropwise addition for 60s, the dropwise addition is repeated at a certain interval until the addition is completed. The temperature is controlled at 125-135 ° C. When the temperature is 130- At 135 ° C, the pressure is adjusted to 0.6 MPa, and the control time is 20-30 minutes. The dropping process is continuously dispersed with ultrasonic waves at 20-33 KHz. When the dropping is completed, the pressure is adjusted to normal pressure and the temperature is adjusted to 130-140. ℃, heat preservation reaction for 50-60min, and then condensation reaction, during which formaldehyde is continuously added dropwise, using microwave heating, stirring speed is 550-700r / min, heating treatment is performed at 15-20 ℃ per minute to control the temperature at 85- 93 ℃, holding time is 35-50min;

   S3: neutralization processing

   Add a neutralizing agent to S2 to perform a neutralization treatment by stirring with a magnetic bar, and adjust the pH to 7;

   S4: Distillation

   Atmospheric distillation treatment by hot air bath, heating to boiling state within 20-25min, maintaining the state for 25min, stirring by centrifugation speed 900-1000r / min, standing still, decompression during reflux Distillation, sampling to measure the softening point, control the temperature between 85-107 ℃, if it can not reach 85 ℃ should still extend the vacuum time, and obtain the resin by vacuum distillation;

   S5: Granulation

   Turn on the granulator, turn on the pump, and adjust the rotation speed until the granules formed are semi-circular without tailing, which means that the granulation is successfully bagged.
2. The new green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength according to claim 1, wherein in the step S1, the inert gas is composed of helium and argon, and the inert gas is composed of helium and argon. The argon is composed of a volume ratio of 2: 3. Before the resorcinol is added, the temperature is 65-110 ° C in a dry inert gas atmosphere, and it is passed into the deionized water at a gas flow rate of 0.1-2L / min. Deionized water is heated for 10-15min. When resorcinol is added, the heated solution is refluxed under a dry inert gas at room temperature. The reflux time is 25-40min to obtain a resorcinol solution. .
3. The new green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength according to claim 1, wherein in step S2, the formaldehyde: resorcinol: ethylvinylbenzene: composite acid catalyst The weight ratio is 20-30: 55-65: 25-30: 3-5.
4. The novel green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength according to claim 1, characterized in that, in step S2, the composite acid catalyst comprises methylmalonic acid, toluenesulfonic acid, maleic acid The diacids are mixed according to a certain proportion. During the preparation process, malonic acid, toluenesulfonic acid, and maleic acid are respectively mixed with water to obtain respective saturated solutions. The three saturated solutions are mixed and heated by microwave to The magnetic rod stirring treatment is performed at 60-80 ° C, and the mixed mixed solution is added with a porous carrier aluminum silicate under a vacuum of 0.4-0.6KPa, left for 12-16h, and dried at a low temperature of 5-6 ° C. The composite acid catalyst in the early stage is obtained by calcination, and then the composite acid catalyst is cooled by quick freezing, the quick freezing temperature is -12 to -15 ° C, the quick freezing time is 10-16 minutes, and the static acid treatment is carried out at room temperature, and the composite acid catalyst is broken through 20-30 meshes.
5. The new green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength according to claim 1, characterized in that the neutralizing agent in step S3 comprises sodium hydroxide, monoethanol diisopropanolamine, Lauryl diethanolamine is mixed according to a certain proportion,
6. The new green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength according to claim 1, characterized in that the vacuum degree during the reduced pressure distillation in step S4 is controlled to ≥0.08Mpa, and the temperature is 170 ± 10 ℃.
7. The new green environmental protection process for preparing a resorcinol formaldehyde resin with high adhesive strength according to claim 1, characterized in that in step S5, the resin is firstly subjected to ultrasonic dispersion treatment, and then the processed product is pulsed. The resin is atomized and sprayed, and the rotation speed is adjusted to 1200-1600 rpm for granulation treatment.
8. The new green environmental protection process for preparing resorcinol formaldehyde resin with high adhesive strength according to claim 1, characterized in that before the neutralization treatment in step S3, the neutralizing agent is heated in a water bath to 65-75 ℃, adding neutralizing agent at intervals of 5min, during which the resin is subjected to air blowing and evaporation at a temperature of 5-9 ° C to adjust the pH value.