阅读说明：本技术 一种复合防火门芯板的制备方法 (Preparation method of composite fireproof door core plate ) 是由 刘鹏 于 2019-10-16 设计创作，主要内容包括：本发明属于建筑材料技术领域,具体涉及一种复合防火门芯板的制备方法。本发明将液体石蜡乳化后与乳化丙烯酸混合,将热塑性树脂、改性乳化液体石蜡、含镁纤维浆、硅藻土基防火填料、脱硫石膏粉混合预热,最后得到复合防火门芯板；将硅藻土基防火填料填入木浆纤维中,使镁盐水泥与木浆纤维粘合作用增强,提升防火门芯板的强度,硅藻土基防火填料中硅藻土孔隙中填充大量的聚磷酸铵,提高防火门芯板的防火性能；用表面活性剂乳化液体石蜡,使防火门芯板的防潮性能增强,防火门芯板以树脂胶作为浸胶,不易受湿气侵蚀,并且三聚氰胺不含碳,防火性高,液体石蜡在硅藻土的微孔吸附作用下,有持久的防潮性能,保持体积稳定性,具有广阔的应用前景。(The invention belongs to the technical field of building materials, and particularly relates to a preparation method of a composite fireproof door core plate. Emulsifying liquid paraffin, mixing the emulsified liquid paraffin with emulsified acrylic acid, mixing and preheating thermoplastic resin, modified emulsified liquid paraffin, magnesium-containing fiber pulp, diatomite-based fireproof filler and desulfurized gypsum powder to obtain a composite fireproof door core plate; the diatomite-based fireproof filler is filled into the wood pulp fibers, so that the bonding effect of magnesium salt cement and the wood pulp fibers is enhanced, the strength of the fireproof door core plate is improved, and a large amount of ammonium polyphosphate is filled in diatomite pores in the diatomite-based fireproof filler, so that the fireproof performance of the fireproof door core plate is improved; the liquid paraffin is emulsified by the surfactant, so that the moisture resistance of the fireproof door core plate is enhanced, the fireproof door core plate is not easily corroded by moisture because resin glue is used as glue dipping, the melamine does not contain carbon, the fireproof performance is high, the liquid paraffin has lasting moisture resistance under the micropore adsorption action of the diatomite, the volume stability is kept, and the application prospect is wide.)

1. A preparation method of a composite fireproof door core plate is characterized by comprising the following specific preparation steps:

mixing and preheating thermoplastic resin, modified emulsified liquid paraffin, magnesium-containing fiber pulp, diatomite-based fireproof filler and desulfurized gypsum powder to 200-220 ℃ to obtain preheated slurry, pouring the preheated slurry into a fireproof door core plate mold, paving grid cloth when the slurry reaches the middle height of the mold, standing for 12-15 hours, demolding, then placing the mold in a solidification bath for soaking for 30-35 minutes, taking out the mold, washing the mold with absolute ethyl alcohol, placing the mold in resin glue for glue dipping treatment for 20-30 minutes, taking out the mold, and scraping the surface of the mold after the surface glue solution is completely cured to obtain a composite fireproof door core plate;

the magnesium-containing fiber pulp is prepared by the following specific steps:

(1) pouring 60-65 mL of 0.4mol/L phosphoric acid solution into a three-neck flask with an air duct, heating the mixture in an oil bath to 70-80 ℃, adding urea into the three-neck flask, continuously heating the mixture to 130-135 ℃ at a heating rate of 2-3 ℃/min, adding 10-12 g of diatomite into the three-neck flask, and carrying out heat preservation treatment for 20-30 min to obtain a mixed product;

(2) pouring the mixed product into a tray, transferring the tray into an oven with a set temperature of 150-200 ℃, curing and drying for 2-3 h, then placing the tray into a mortar for grinding for 30-35 min to obtain a diatomite-based fireproof filler, and mixing sulfate softwood pulp with a solid content of 35%, magnesium oxide powder, aluminum oxide powder and ammonia water with a mass fraction of 15% according to a mass ratio of 10: 3: 1: 5 to obtain magnesium-containing fiber pulp;

the preparation method of the modified emulsified liquid paraffin comprises the following specific steps:

(1) mixing 70-80 parts of liquid paraffin and 300-350 parts of distilled water, adding the mixture into a double-neck flask, heating to 70-80 ℃, adding 4-5 parts of surfactant to preheat the water emulsion to 60-65 ℃, adding the mixture into the double-neck flask, starting a stirrer, stirring at a rotating speed of 200-230 r/min, and stirring and emulsifying for 40-45 min to obtain emulsified liquid paraffin;

(2) mixing acrylic acid and emulsified liquid paraffin according to a volume ratio of 1: 5, placing the mixture into a three-neck flask, heating to 70-75 ℃, starting a stirrer to stir and emulsify at a rotating speed of 300-350 r/min for 20-30 min, dropwise adding 40-45 mL of 10% potassium thiosulfate solution into the three-neck flask at a dropwise adding rate of 4-5 mL/min by using a dropping funnel, and stirring and reacting for 40-50 min after dropwise adding is finished to obtain the modified emulsified liquid paraffin.

2. The method of claim 1, wherein the method comprises the steps of: the composite fireproof door core plate comprises, by weight, 20-30 parts of thermoplastic resin, 40-50 parts of modified emulsified liquid paraffin, 70-100 parts of magnesium-containing fiber pulp, 20-25 parts of diatomite-based fireproof filler and 50-60 parts of desulfurized gypsum powder.

3. The method of claim 1, wherein the method comprises the steps of: the coagulating bath in the specific preparation steps of the composite fireproof door core plate is obtained by mixing a 45 mass percent sulfuric acid solution and a 35 mass percent sodium sulfate solution according to a volume ratio of 3: 1.

4. The method of claim 1, wherein the method comprises the steps of: the resin adhesive in the specific preparation step of the composite fireproof door core plate is formed by compounding melamine and 20 mass percent aqueous solution of formaldehyde in equal mass.

5. The method of claim 1, wherein the method comprises the steps of: the thermoplastic resin in the specific preparation step of the composite fireproof door core plate is one of PPE resin, PI resin and PEEK resin.

6. The method of claim 1, wherein the method comprises the steps of: the specific preparation step (1) of the magnesium-containing fiber pulp controls the molar ratio of the added phosphoric acid to the urea to be 1: 2.

7. The method of claim 1, wherein the method comprises the steps of: the magnesium-containing fiber pulp is prepared by mixing sulfate softwood pulp with a solid content of 35%, magnesium oxide powder, aluminum oxide powder and ammonia water with a mass fraction of 15% in the step (2) at a mass ratio of 10: 3: 1: 5.

8. The method of claim 1, wherein the method comprises the steps of: the surfactant in the specific preparation step (1) of the modified emulsified liquid paraffin is one of alkylphenol ethoxylate, nonylphenol ethoxylate, octylphenol ethoxylate, dodecyl ethoxylate and dinonylphenol ethoxylate.

9. The method of claim 1, wherein the method comprises the steps of: the modified emulsified liquid paraffin is prepared in the step (2) in a specific mixing volume ratio of acrylic acid to emulsified liquid paraffin of 1: 5.

Technical Field

The invention belongs to the technical field of building materials, and particularly relates to a preparation method of a composite fireproof door core plate.

Background

The fireproof door is composed of a framework, a door core filling material and fireproof hardware, the filling material of the door core plate is the core material of the fireproof door, and the quality and the performance of the fireproof door are particularly important. The filling material of the door core plate is traditionally rock wool, aluminum silicate wool, mineral wool, perlite plates, foamed magnesium oxychloride cement plates, foamed cement plates and other materials. Although the materials are light in weight and good in heat insulation, the energy consumption is high in the production process, the materials are formed by organic bonding agents, pollution is generated in the production process and the use process, the environment-friendly requirement is difficult to achieve, and meanwhile, the problems that the core plate of the fireproof door is poor in integrity, short in fire-resistant limit time, poor in mechanical property, easy to deform, high in comprehensive cost, inconvenient to use and the like exist; although the perlite fireproof door core board has better fireproof performance, the board is formed by adopting strong alkaline adhesives such as water glass and the like, has corrosivity and poorer strength and toughness, and the product is easy to damage in the production and use processes; the vermiculite fire door core plate is formed by adopting an organic or inorganic adhesive, and has the problems of complex production process, regional limitation on raw material sources, large dry density and high comprehensive cost; although the core plate of the magnesium oxychloride cement fireproof door has the characteristics of light weight, high strength, low cost and the like, key technical problems of unstable volume, moisture absorption, halogen return and frost return, warping deformation, short fireproof limit time and the like are not solved effectively all the time; the fireproof door core plate prepared by foaming Portland cement or sulphoaluminate cement has the advantages of easy pulverization on the surface, low later strength and poor stability, and the quality of the fireproof door is seriously influenced.

At present, with the development of the national real estate industry, the demand of fireproof building materials is wider and higher. The fire door has multiple functions and practicability of sealing, fire prevention, partition, safety, heat preservation, sound insulation and the like, becomes an essential component in a building, and is increasingly paid high attention by national building departments and national fire control headquarters. The main materials of the fireproof door core are rock wool, a glass magnesium board, a perlite board, a foaming cement board and the like, the inorganic materials are generally easy to have low slag falling strength and easy to peel off under impact, and in addition, as the used materials mostly contain organic matters, the fireproof performance is reduced, and the smoke toxicity does not reach the standard.

The domestic fireproof door core plate is mainly divided into two types, the first type is prepared by mixing sodium silicate as a binder and expanded perlite as a filler and then performing a high-temperature hot pressing process, the high-temperature hot pressing is performed at 200-300 ℃, the production cycle is long, the production efficiency is low, the cost is high, and the production process can pollute the environment. The second type of perlite fireproof door core board prepared by using magnesium chloride as a binder can cause halogen return, and the magnesium chloride is decomposed into chloride ions and magnesium ions to form a weakly acidic primary battery, so that a steel door plate is corroded and rusted. Therefore, many fireproof door manufacturers begin to search fireproof door core plates for replacing magnesium oxychloride cement, such as the fireproof door core plates of water glass perlite platelets, rock wool plates and the like, but the production efficiency of the fireproof door core plates is low in the production process, and high-grade pattern fireproof doors cannot be produced. In conclusion, fireproof door manufacturers cannot find an ideal door core plate product capable of meeting fireproof door manufacturers in the market.

The magnesium oxysulfate cement is an inorganic cementing material prepared by mixing magnesium sulfate solution with light-burned magnesia powder. The magnesium oxysulfate cement has the characteristics of light weight, fire resistance, coagulated block, sound insulation, heat insulation and the like. Compared with magnesium oxychloride cement, the magnesium oxysulfate cement has good temperature resistance, poor corrosion to reinforcing steel bars and no halogen return, so that the magnesium oxysulfate cement is gradually accepted by people and has very outstanding advantages when being used as a core plate of a fireproof door.

Present fire door core exists: unstable volume, short fire-resistant limit, general strength, easy peeling under impact, poor stability and the like.

Therefore, the invention provides the excellent fireproof door core plate, which has positive significance to the technical field of building materials.

Disclosure of Invention

The invention mainly solves the technical problem, and provides a preparation method of a composite fireproof door core plate, aiming at the defects that most of the existing fireproof door core plates are made of magnesium oxysulfate cement and magnesium oxychloride cement, but the magnesium cement fireproof door core plates are easy to absorb moisture to cause unstable volume, have short fireproof limit time and further improve the fireproof performance.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

a preparation method of a composite fireproof door core plate is characterized by comprising the following specific preparation steps:

mixing and preheating thermoplastic resin, modified emulsified liquid paraffin, magnesium-containing fiber pulp, diatomite-based fireproof filler and desulfurized gypsum powder to 200-220 ℃ to obtain preheated slurry, pouring the preheated slurry into a fireproof door core plate mold, paving grid cloth when the slurry reaches the middle height of the mold, standing for 12-15 hours, demolding, then placing the mold in a solidification bath for soaking for 30-35 minutes, taking out the mold, washing the mold with absolute ethyl alcohol, placing the mold in resin glue for glue dipping treatment for 20-30 minutes, taking out the mold, and scraping the surface of the mold after the surface glue solution is completely cured to obtain a composite fireproof door core plate;

the magnesium-containing fiber pulp is prepared by the following specific steps:

(1) pouring 60-65 mL of 0.4mol/L phosphoric acid solution into a three-neck flask with an air duct, heating the mixture in an oil bath to 70-80 ℃, adding urea into the three-neck flask, continuously heating the mixture to 130-135 ℃ at a heating rate of 2-3 ℃/min, adding 10-12 g of diatomite into the three-neck flask, and carrying out heat preservation treatment for 20-30 min to obtain a mixed product;

(2) pouring the mixed product into a tray, transferring the tray into an oven with a set temperature of 150-200 ℃, curing and drying for 2-3 h, then placing the tray into a mortar for grinding for 30-35 min to obtain a diatomite-based fireproof filler, and mixing sulfate softwood pulp with a solid content of 35%, magnesium oxide powder, aluminum oxide powder and ammonia water with a mass fraction of 15% according to a mass ratio of 10: 3: 1: 5 to obtain magnesium-containing fiber pulp;

the preparation method of the modified emulsified liquid paraffin comprises the following specific steps:

(1) mixing 70-80 parts of liquid paraffin and 300-350 parts of distilled water, adding the mixture into a double-neck flask, heating to 70-80 ℃, adding 4-5 parts of surfactant to preheat the water emulsion to 60-65 ℃, adding the mixture into the double-neck flask, starting a stirrer, stirring at a rotating speed of 200-230 r/min, and stirring and emulsifying for 40-45 min to obtain emulsified liquid paraffin;

(2) mixing acrylic acid and emulsified liquid paraffin according to a volume ratio of 1: 5, placing the mixture into a three-neck flask, heating to 70-75 ℃, starting a stirrer to stir and emulsify at a rotating speed of 300-350 r/min for 20-30 min, dropwise adding 40-45 mL of 10% potassium thiosulfate solution into the three-neck flask at a dropwise adding rate of 4-5 mL/min by using a dropping funnel, and stirring and reacting for 40-50 min after dropwise adding is finished to obtain the modified emulsified liquid paraffin. The composite fireproof door core plate comprises, by weight, 20-30 parts of thermoplastic resin, 40-50 parts of modified emulsified liquid paraffin, 70-100 parts of magnesium-containing fiber pulp, 20-25 parts of diatomite-based fireproof filler and 50-60 parts of desulfurized gypsum powder.

The coagulating bath in the specific preparation steps of the composite fireproof door core plate is obtained by mixing a 45 mass percent sulfuric acid solution and a 35 mass percent sodium sulfate solution according to a volume ratio of 3: 1.

The resin adhesive in the specific preparation step of the composite fireproof door core plate is formed by compounding melamine and 20 mass percent aqueous solution of formaldehyde in equal mass.

The thermoplastic resin in the specific preparation step of the composite fireproof door core plate is one of PPE resin, PI resin and PEEK resin.

The specific preparation step (1) of the magnesium-containing fiber pulp controls the molar ratio of the added phosphoric acid to the urea to be 1: 2.

The magnesium-containing fiber pulp is prepared by mixing sulfate softwood pulp with a solid content of 35%, magnesium oxide powder, aluminum oxide powder and ammonia water with a mass fraction of 15% in the step (2) at a mass ratio of 10: 3: 1: 5.

The surfactant in the specific preparation step (1) of the modified emulsified liquid paraffin is one of alkylphenol ethoxylate, nonylphenol ethoxylate, octylphenol ethoxylate, dodecyl ethoxylate and dinonylphenol ethoxylate.

The modified emulsified liquid paraffin is prepared in the step (2) in a specific mixing volume ratio of acrylic acid to emulsified liquid paraffin of 1: 5.

The invention has the beneficial effects that:

(1) the invention emulsifies the liquid paraffin and then mixes the liquid paraffin with emulsified acrylic acid, adds initiator for heating reaction to obtain modified emulsified liquid paraffin, mixes phosphoric acid and urea for reaction and then adds diatomite for heat preservation and compounding, obtains diatomite-based fireproof filler through drying and grinding, mixes the needle leaf wood pulp, alumina powder, magnesia powder and ammonia water according to a certain mass ratio to obtain magnesium-containing fiber pulp, finally mixes and preheats the thermoplastic resin, the modified emulsified liquid paraffin, the magnesium-containing fiber pulp, the diatomite-based fireproof filler and the desulfurized gypsum powder, pours the mixture into a fireproof door core plate mould, demoulds the mould, uses a coagulating bath for dipping, washes by absolute ethyl alcohol and then carries out gum dipping treatment, and finally scrapes the glue solution to obtain the composite fireproof door core plate after solidification. The wood pulp fibers with negative electricity around are aggregated and bonded, so that the bonding effect of magnesium salt cement and the wood pulp fibers is enhanced, the strength of the core plate of the fire door is enhanced, the fire resistance is enhanced, a large amount of ammonium polyphosphate is filled in diatomite pores in the diatomite-based fire-proof filler, the ammonium polyphosphate is easily decomposed by heating to generate phosphoric acid so as to dehydrate the wood fibers, solid-phase layer polyphosphoric acid or polymetaphosphoric acid which can further generate firm hard shells at high temperature can cover the fiber surface, the reactions can promote the carbonization of the fibers to cause incomplete oxidation of pyrolysis mixed products, meanwhile, ammonia, water vapor and the like generated by the decomposition of the ammonium polyphosphate can generate a fire-proof effect in a gas phase, and the gas-phase combustion is inhibited to cause the aggravat;

(2) the invention uses surfactant to emulsify liquid paraffin, the emulsification paraffin and acrylic monomer are emulsified under the initiation of potassium thiosulfate to obtain modified emulsification liquid paraffin, the tiny drops of paraffin are evenly distributed among wood pulp fibers, carboxyl in the modified emulsification paraffin can generate esterification reaction with hydroxyl in wood fibers and magnesium cement, the exposed hydroxyl on the surface is reduced, thereby the moisture resistance of the fireproof door core plate is enhanced, the fireproof door core plate takes resin glue as glue dipping, the glue dipping polarity is weak, the melamine is not easy to be eroded by moisture, the melamine does not contain carbon, the fire resistance is high, the melamine can be directly decomposed and sublimated under the high temperature condition, so that a large amount of smoke can not be generated when the surface of the fireproof door core plate is burnt, the main part of the liquid paraffin of the modified emulsification liquid paraffin is straight chain paraffin structure, a large amount of methyl and methylene exist, the bond energy of the methyl and the methylene are larger and are radicals, the waterproof performance is improved, and the liquid paraffin cannot be stored in the fireproof door core plate and cannot seep out under the micropore adsorption effect of the diatomite and the sealing effect of the resin adhesive, so that the fireproof door core plate has lasting moisture resistance, the volume stability of the door core plate is kept, and the fireproof door core plate has a wide application prospect.

Detailed Description

Pouring 60-65 mL of 0.4mol/L phosphoric acid solution into a three-neck flask with an air duct, heating in an oil bath to 70-80 ℃, adding urea into the three-neck flask, and controlling the molar ratio of phosphoric acid to urea to be 1

2, continuously heating to 130-135 ℃ at the heating rate of 2-3 ℃/min, adding 10-12 g of diatomite into the three-neck flask, and carrying out heat preservation treatment for 20-30 min to obtain a mixed product; pouring the mixed product into a tray, transferring the tray into an oven with a set temperature of 150-200 ℃, curing and drying for 2-3 h, then placing the tray into a mortar for grinding for 30-35 min to obtain a diatomite-based fireproof filler, and mixing sulfate softwood pulp with a solid content of 35%, magnesium oxide powder, aluminum oxide powder and ammonia water with a mass fraction of 15% according to a mass ratio of 10: 3: 1: 5 to obtain magnesium-containing fiber pulp; mixing 70-80 parts of liquid paraffin and 300-350 parts of distilled water, adding the mixture into a double-neck flask, heating the mixture to 70-80 ℃, adding 4-5 parts of surfactant to preheat the aqueous emulsion to 60-65 ℃, adding the mixture into the double-neck flask, starting a stirrer, stirring the mixture at a rotating speed of 200-230 r/min, and stirring and emulsifying the mixture for 40-45 min to obtain emulsified liquid paraffin, wherein the surfactant is one of alkylphenol polyoxyethylene ether, nonylphenol polyoxyethylene ether, octylphenol polyoxyethylene ether, dodecyl polyoxyethylene ether and dinonylphenol polyoxyethylene ether; mixing acrylic acid and emulsified liquid paraffin according to the volume ratio of 1: 5, placing the mixture into a three-neck flask, heating the mixture to 70-75 ℃, starting a stirrer to stir and emulsify the mixture for 20-30 min at the rotating speed of 300-350 r/min, dropwise adding 40-45 mL of 10 mass percent potassium thiosulfate solution into the three-neck flask at the dropping speed of 4-5 mL/min by using a dropping funnel, and stirring and reacting for 40-50 min after dropwise adding is finished to obtain modified emulsified liquid paraffin; mixing 20-30 parts by weight of thermoplastic resin, 40-50 parts by weight of modified emulsified liquid paraffin, 70-100 parts by weight of magnesium-containing fiber slurry and 20-25 parts by weight of diatomite-based fireproof filler 50-60 parts by weight of desulfurized gypsum powder, preheating to 200-220 ℃ to obtain preheated slurry, pouring the preheated slurry into a fireproof door core plate mold, laying mesh cloth when the slurry reaches the middle height of the mold, standing for 12-15 h, demolding, then placing the mold in a coagulating bath for soaking for 30-35 min, taking out, washing with absolute ethyl alcohol, then placing the mold in resin adhesive for impregnation treatment for 20-30 min, taking out, completely solidifying the surface adhesive solution, and scraping the surface to obtain the composite fireproof door core plate; the coagulating bath is obtained by mixing 45% of sulfuric acid solution and 35% of sodium sulfate solution according to the volume ratio of 3: 1, the resin glue is formed by compounding melamine and 20% of formaldehyde aqueous solution in mass percentage, and the thermoplastic resin is one of PPE resin, PI resin and PEEK resin.