阅读说明：本技术 一种以环保型酚醛树脂制作玻璃纤维网盖的制作方法 (Method for manufacturing glass fiber mesh cover by using environment-friendly phenolic resin ) 是由 谢果 刘琪 叶应松 于 2019-02-22 设计创作，主要内容包括：本发明提供了一种以环保型酚醛树脂制作玻璃纤维网盖的制作方法,环保型酚醛树脂制作方法,原料按质量百分数计：苯酚：38-48%；甲醛水溶液：43-57%；水：1-10%；碱性催化剂：1-7%；步骤：将上述质量百分比的苯酚和甲醛水溶液混合,20-40℃搅拌5-20分钟；加入上述质量百分比的水、碱性催化剂,升至70-90℃反应60-140分钟；保持温度为70-90℃调节黏度60-140cp.s,冷却,出料,获环保型酚醛树脂。将环保型酚醛树脂复配成浸渍胶水用于网盖的制作。环保型酚醛树脂的制作方法条件温和,无污染。不用稀释就可用于网盖的生产,且降低了固化温度和时间,减少有机物挥发,降低成产成本。(The invention provides a method for manufacturing a glass fiber net cover by using environment-friendly phenolic resin, which comprises the following raw materials in percentage by mass: phenol: 38 to 48 percent; aqueous formaldehyde solution: 43 to 57 percent; water: 1 to 10 percent; basic catalyst: 1 to 7 percent; the method comprises the following steps: mixing the phenol and the formaldehyde water solution according to the mass percentage, and stirring for 5-20 minutes at 20-40 ℃; adding the water and the alkaline catalyst in percentage by mass, and heating to 70-90 ℃ to react for 60-140 minutes; keeping the temperature at 70-90 ℃, adjusting the viscosity to 60-140cp.s, cooling, discharging and obtaining the environment-friendly phenolic resin. Compounding environment-friendly phenolic resin into impregnating glue for manufacturing the mesh cover. The preparation method of the environment-friendly phenolic resin has mild conditions and no pollution. The method can be used for producing the mesh cover without dilution, and can reduce the curing temperature and time, reduce the volatilization of organic matters and reduce the production cost.)

1. A method for preparing environment-friendly phenolic resin, which is characterized in that,

the environment-friendly phenolic resin comprises the following raw materials in percentage by mass: phenol: 38 to 48 percent; aqueous formaldehyde solution: 43 to 57 percent; water: 1 to 10 percent; basic catalyst: 1 to 7 percent;

the method comprises the following steps:

(1) mixing the phenol and the formaldehyde water solution according to the mass percentage, and stirring for 5-20 minutes at 20-40 ℃;

(2) adding the water and the alkaline catalyst in percentage by mass, and heating to 70-90 ℃ to react for 60-140 minutes;

(3) keeping the reaction temperature at 70-90 ℃, adjusting the viscosity to 60-140cp.s, cooling, and discharging to obtain the environment-friendly phenolic resin.

2. The method for preparing the environment-friendly phenolic resin as claimed in claim 1, wherein the mass concentration of the formaldehyde aqueous solution is 36-44%.

3. The method for preparing the environment-friendly phenolic resin as claimed in claim 1, wherein the mass concentration of the phenol is greater than or equal to 98%.

4. The method for preparing the environment-friendly phenolic resin as claimed in claim 1, wherein the alkaline catalyst is one or a mixture of sodium hydroxide, potassium hydroxide or barium hydroxide.

5. The method for preparing the environment-friendly phenolic resin as claimed in claim 1, wherein the viscosity is adjusted in the step (3) to be measured once every 5-10 minutes.

6. The environment-friendly phenolic resin prepared by the preparation method of any one of claims 1 to 5.

7. The method for manufacturing the glass fiber net cover by using the environment-friendly phenolic resin as claimed in claim 6, wherein the environment-friendly phenolic resin and the coupling agent are compounded to form the impregnating glue.

8. The method for manufacturing the glass fiber net cover by using the environment-friendly phenolic resin as claimed in claim 7, wherein the raw materials of the impregnating glue comprise, by weight, 100 parts of the environment-friendly phenolic resin and 0.6-1.5 parts of a coupling agent.

9. The method for manufacturing the glass fiber mesh cover by using the environment-friendly phenolic resin as claimed in claim 7 or 8, wherein a pigment is further added to the impregnating glue, and the pigment accounts for 0.2-0.5 part by weight.

10. The method for manufacturing the glass fiber mesh cover by using the environment-friendly phenolic resin according to any one of claims 7 to 9, which is characterized by comprising the following steps of:

step one, soaking glass fiber cloth in soaking glue compounded by environment-friendly phenolic resin;

step two, carrying out pre-baking treatment on the glass fiber mesh cloth subjected to the dipping treatment in the step one;

thirdly, overlapping the glass fiber cloth subjected to the pre-baking treatment in the second step according to the specification of the glass fiber net cover and the requirements of the strength of the sand leaf disc and the sand disc, and standing and pressing;

step four, cutting the glass fiber mesh cloth laminated in the step three according to the specification of the glass fiber mesh cover to obtain a glass fiber mesh cover blank;

step five, binding the glass fiber net cover blank cut in the step four with a grinding wheel hole insert by using a ring binding machine, and shaping the glass fiber net cover blank by using a shaping mold;

step six, curing the glass fiber net cover blank shaped in the step five by using curing equipment, wherein the curing temperature is 110-130 ℃, and the curing time is 4-5 hours;

and step seven, rounding the glass fiber net cover blank shaped in the step six by using polishing rounding equipment, and finally packaging into a glass fiber net cover finished product.

Technical Field

The invention relates to the technical field of glass fiber net cover processes, in particular to a method for manufacturing a glass fiber net cover by using environment-friendly phenolic resin.

Background

At present, synthetic resin used for the glass fiber net cover is basically alcohol-soluble (thermoplastic) phenolic resin, the manufactured glass fiber net cover is called as the alcohol-soluble net cover for short, curing agents such as hexamethylene tetramine, paraformaldehyde and the like are required to be added in the curing process, and the hexamethylene tetramine is a commonly used curing agent at present. The impregnating glue used for preparing the glass fiber net cover mainly comprises solid phenolic resin, liquid phenolic resin, an alcohol solvent, hexamethylenetetramine, pigment and the like, wherein the curing amount of the impregnating solution is 59 +/-8%, and the alcohol solvent is used for dissolving the solid phenolic resin, adjusting the viscosity of the impregnating solution and increasing the permeability of the impregnating solution and the glass fiber cloth. The resin used for producing the glass fiber mesh cover is thermoplastic phenolic resin, the curing temperature of the resin is generally 170-190 ℃, the heat preservation is required to be carried out at the temperature, the heat preservation time is 4-6h, and the whole curing process is generally more than 10 h. Among them, methanol is the most commonly used alcohol solvent because of its good solubility and low price. However, methanol is a flammable, volatile and low-toxicity substance, and the flash point of the methanol is 12 ℃, so that a impregnator using alcohol-soluble phenolic resin is generally electrically heated, and safety accidents such as explosion and the like caused by volatilization of the methanol can be prevented. Methanol is also a VOC (volatile organic compound) and the related policy has regulated the methanol gas content of the production plant. When the glass fiber cloth is soaked in the alcohol-soluble phenolic resin in the pre-baking process, methanol volatilizes from the soaking liquid, the volatilization amount accounts for about 30% of the weight of the soaking liquid, the specific volatilization amount is determined by the solid content of the soaking liquid, and common glass fiber net cover manufacturers cannot recover the methanol, and the methanol-soluble phenolic resin is directly discharged as tail gas, so that the problem of air pollution is easily caused. In addition, the sizing die of the glass fiber net cover is an aluminum product, when the glass fiber net cover is at 190 ℃ with 170 ℃ and under a certain sizing pressure, the aluminum sizing die is easy to deform, the size change of the sizing die exceeds the specified deviation, key indexes such as the thickness of the produced glass fiber net cover exceed the allowable range of quality control, the internal compression ratio of the net cover is unstable, the quality fluctuation of the net cover is large, and the quality risk is increased. Therefore, the setting die needs to be regularly organized and manually detected and selected, and unqualified setting dies are selected and replaced. According to the above description, the main disadvantages of the production of the mesh cover by using the alcohol-soluble phenolic resin are as follows: the safety risk is high, the energy consumption is high, the environmental pollution is large, the cost is high, and the staff is harmed to the health.

Aiming at the current environmental protection policy and the purpose of reducing the production cost, the adoption of the environmental protection type phenolic resin to replace the alcohol-soluble phenolic resin is imperative.

Disclosure of Invention

Aiming at the problems, the invention provides a method for manufacturing a glass fiber mesh cover by using environment-friendly phenolic resin, the environment-friendly phenolic resin is mild in preparation conditions and simple in equipment, dehydration is not needed in the preparation process, the method is green and pollution-free, the prepared environment-friendly phenolic resin can be directly used for producing the glass fiber mesh cover without dilution, the strength of the glass fiber mesh cover prepared by using the environment-friendly phenolic resin is basically consistent with that of an alcohol-soluble glass fiber mesh cover, meanwhile, the curing temperature is reduced to 120 +/-10 ℃ in the curing process of the glass fiber mesh cover, and the curing time is shortened to 4-5 h. In addition, the environment-friendly phenolic resin adopts pollution-free water to replace alcohols as a solvent, the volatile matter of the phenolic resin is mainly water, the production cost is greatly reduced, the turnover time of the shaping mold is greatly shortened, the production efficiency is greatly improved, the pollution of the volatile organic matter to the environment due to volatilization is greatly reduced, the safety of a production workshop is greatly improved, and the health of staff can be ensured.

The technical problem to be solved by the invention is realized by adopting the following technical scheme:

a method for preparing environment-friendly phenolic resin,

the environment-friendly phenolic resin comprises the following raw materials in percentage by mass: phenol: 38 to 48 percent; aqueous formaldehyde solution: 43 to 57 percent; water: 1 to 10 percent; basic catalyst: 1 to 7 percent;

the method comprises the following steps:

(1) mixing the phenol and the formaldehyde water solution according to the mass percentage, and stirring for 5-20 minutes at 20-40 ℃;

(2) adding the water and the alkaline catalyst in percentage by mass, and heating to 70-90 ℃ to react for 60-140 minutes;

(3) keeping the reaction temperature at 70-90 ℃, adjusting the viscosity to 60-140cp.s, cooling, and discharging to obtain the environment-friendly phenolic resin.

Preferably, the mass concentration of the formaldehyde aqueous solution is 36-44%.

Preferably, the mass concentration of phenol is 98% or more.

Preferably, the alkaline catalyst is one or a mixture of sodium hydroxide, potassium hydroxide or barium hydroxide.

Preferably, the step (3) of adjusting the viscosity is to measure the viscosity once every 5 to 10 minutes.

The preparation method of the impregnating glue for the glass fiber net cover comprises the steps of compounding the environment-friendly phenolic resin and the coupling agent to prepare the impregnating glue.

Preferably, the raw materials of the impregnating glue comprise, by weight, 100 parts of environment-friendly phenolic resin and 0.6-1.5 parts of coupling agent.

Preferably, the impregnating glue is further added with a pigment, and the pigment accounts for 0.2-0.5 part by weight.

A manufacturing method of a glass fiber net cover comprises the following steps:

step one, soaking glass fiber cloth in soaking glue compounded by environment-friendly phenolic resin;

step two, carrying out pre-baking treatment on the glass fiber mesh cloth subjected to the dipping treatment in the step one;

thirdly, overlapping the glass fiber cloth subjected to the pre-baking treatment in the second step according to the specification of the glass fiber net cover and the requirements of the strength of the sand leaf disc and the sand disc, and standing and pressing;

step four, cutting the glass fiber mesh cloth laminated in the step three according to the specification of the glass fiber mesh cover to obtain a glass fiber mesh cover blank;

step five, binding the glass fiber net cover blank cut in the step four with a grinding wheel hole insert by using a ring binding machine, and shaping the glass fiber net cover blank by using a shaping mold;

step six, curing the glass fiber net cover blank shaped in the step five by using curing equipment, wherein the curing temperature is 110-130 ℃, and the curing time is 4-5 hours;

and step seven, rounding the glass fiber net cover blank shaped in the step six by using polishing rounding equipment, and finally packaging into a glass fiber net cover finished product.

The environment-friendly phenolic resin is obtained by mixing phenol and formaldehyde aqueous solution, then carrying out copolymerization reaction under the action of an alkaline catalyst, and then controlling the viscosity of a final product. And is suitable for impregnation of the glass fiber net cover, thereby enabling the manufacture of the glass fiber net cover. The environment-friendly phenolic resin provided by the invention has the advantages that the preparation reaction conditions are mild, dehydration is not required in the preparation process, and the prepared environment-friendly phenolic resin has good water solubility, moderate solid content and low viscosity. When the environment-friendly phenolic resin is compounded into the mesh cloth impregnating glue, no diluent is required to be added, the compounding operation is simple, the compounding time is short, and the service life of the impregnating glue is long. And because the environment-friendly phenolic resin belongs to water-soluble phenolic resin, an alcohol solvent is not needed when the environment-friendly phenolic resin is used for compounding the impregnating glue, and because the alcohol solvent is not used, the organic volatile matter content of the glass fiber mesh cloth impregnated with the impregnating glue is extremely low in the pre-baking and curing stages, so that the safety coefficient of a production workshop is greatly improved, and the health of staff is ensured. Meanwhile, when the environment-friendly phenolic resin compounded impregnating glue is used for manufacturing the glass fiber net cover, a curing agent is not required to be added, and the curing temperature required in the curing process is low, the curing time is short, the turnover efficiency of a shaping mold is high, so that the production cost can be greatly reduced. The invention adopts alkali as catalyst, the phenolic resin can be cured automatically at 105 ℃, the curing temperature is 120 +/-10 ℃, the curing process is subdivided into room temperature rising to 110 ℃, and the time is about 90 min; the temperature of the curing section is 120 +/-10 ℃, and the time is about 120 min; the cooling section is cooled from 120 +/-10 ℃ to 60 +/-10 ℃ for about 40min, the time of the whole curing stage is about 270min, and the specific curing process can be properly adjusted according to the change of the diameter and the layer number of the net cover. Alcohol is needed to be added into the alcohol-soluble phenolic resin in the prior art as a solvent, and although the gummed glass fiber mesh cloth is subjected to pre-baking treatment, the alcohol-soluble phenolic resin also contains a part of alcohol solvent, water and other volatilizable solvents and auxiliaries, the boiling points of the solvents are different, and the time for removing volatile components at a low temperature section is longer and is generally not less than 2 hours. The alcohol-soluble phenolic resin is in a linear structure, the curing agent is required to be added to realize the curing, the curing agent is usually hexamethylenetetramine, the initial decomposition temperature of the curing agent in the alcohol-soluble phenolic resin is 110 +/-10 ℃, the alcohol-soluble phenolic resin is used as the glass fiber mesh cloth impregnation liquid, the main component of the impregnation liquid is solid phenolic (alcohol-soluble) resin, the flowing (melting) temperature of the impregnation liquid is consistent with the decomposition of the hexamethylenetetramine, and therefore the stage is generally kept for about 2 hours. The temperature is raised from 110 +/-10 ℃ to 170-190 ℃, and the time is generally not less than 1.5 h. In order to ensure the curing degree of the phenolic resin, the temperature is required to be kept for more than 4h at the temperature of 170-190 ℃. Meanwhile, the curing shrinkage rate of the phenolic resin is larger, and the phenolic resin is a glass fiber mesh cloth reinforced product, so that the mesh cover can be taken out of the shaping mold at a low temperature (60 +/-10 ℃), and the temperature period is longer than or equal to 1 h. Therefore, the curing temperature of the impregnating glue prepared by compounding the alcohol-soluble phenolic resin in the prior art for preparing the glass fiber mesh cover is 170-190 ℃, and the curing time generally exceeds 10 h. In addition, this application is because solidification temperature reduces to the problem of aluminium system stock mould mutability has been solved, therefore can prevent that the size change of stock mould from surpassing the regulation deviation, has guaranteed the production quality of glass fiber net lid.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The performance test indexes of the environment-friendly phenolic resin are as follows:

viscosity: the viscosity test was carried out according to GB/T2794-.

Water solubility: the water solubility test was performed according to GB/T24412-.

Solid content: the solid content test was carried out according to GB/T24412-.