阅读说明：本技术 人造板用磷铝无醛胶粘剂的制备方法 (Preparation method of phosphorus-aluminum formaldehyde-free adhesive for artificial board ) 是由 谢拥群 吴振增 陈汀杰 李德宏 魏微 侯鑫均 魏起华 牛敏 林铭 刘景宏 于 2019-10-11 设计创作，主要内容包括：本发明涉及一种人造板用磷铝无醛胶粘剂的制备方法,由磷酸、铝化合物、多价金属盐或者氧化物、硼化物经水热反应制备得到粘度为30-600 mPa.S,固含量为40-85%的一种无醛环保人造板用胶粘剂。该产品具有强度好、耐高温、阻燃防霉等特点。本发明的优点在于原料来源广泛、价格低廉、操作简便易行、生产过程不产生有毒有害物质,且产品具有良好的力学、阻燃防霉能性能等,有望成为新型的环保型人造板胶粘剂。(The invention relates to a preparation method of a phosphorus-aluminum aldehyde-free adhesive for artificial boards, which is an aldehyde-free environment-friendly adhesive for artificial boards, and the adhesive has the viscosity of 30-600 mPa.S and the solid content of 40-85 percent, and is prepared by carrying out hydrothermal reaction on phosphoric acid, an aluminum compound, a multivalent metal salt or oxide and a boride. The product has the characteristics of good strength, high temperature resistance, flame retardance, mildew resistance and the like. The invention has the advantages of wide raw material source, low price, simple and easy operation, no toxic and harmful substances generated in the production process, good mechanical, flame-retardant and mildew-proof performances of the product and the like, and is expected to become a novel environment-friendly artificial board adhesive.)

1. A preparation method of a phosphorus-aluminum formaldehyde-free adhesive for artificial boards is characterized by comprising the following steps: the method comprises the following steps:

(1) taking phosphoric acid solution or hydrogen phosphate solution with certain concentration and an aluminum compound as raw materials, wherein phosphorus and aluminum elements form a certain phosphorus-aluminum ratio, and the solid content of the adhesive is designed;

(2) heating a phosphoric acid solution or a hydrogen phosphate solution in water bath, and then adding an aluminum compound to react for a period of time;

(3) and adding a polyvalent metal salt or a polyvalent metal oxide and a boride into the solution, continuously reacting for a period of time, and cooling to obtain the phosphorus-aluminum formaldehyde-free adhesive for the artificial board.

2. The preparation method of the phosphorus-aluminum aldehyde-free adhesive for the artificial board according to claim 1, wherein the preparation method comprises the following steps: the hydrogen phosphate in the step (1) comprises one of soluble dihydrogen phosphate and soluble monohydrogen phosphate; the aluminum compound comprises one of aluminum hydroxide, aluminum oxide and aluminum nitride; the phosphorus-aluminum ratio is the molar ratio of phosphorus element to aluminum element, and ranges from 2.0:1 to 4.0: 1; the solid content of the adhesive is 40-85%.

3. The preparation method of the phosphorus-aluminum aldehyde-free adhesive for the artificial board according to claim 1, wherein the preparation method comprises the following steps: the water bath temperature in the step (2) is 50-150 ℃, and the reaction time is 20-300 min.

4. The preparation method of the phosphorus aluminum adhesive for artificial boards according to claim 1, which is characterized in that: the polyvalent metal salt and the polyvalent metal oxide in the step (3) are salts and oxides consisting of Zn, Mg, Fe, Cu and Cr; the boride is borax or boric acid; the reaction time is 20-120 min.

5. The phosphorus-aluminum aldehyde-free adhesive for artificial boards prepared by the preparation method according to claim 1, which is characterized in that: the viscosity of the phosphorus-aluminum formaldehyde-free adhesive for the artificial board is 30-600 mPa.S.

6. A method for preparing artificial boards by using the phosphorus-aluminum aldehyde-free adhesive for artificial boards according to claim 5, which is characterized by comprising the following steps: uniformly mixing a phosphorus-aluminum formaldehyde-free adhesive for the artificial board and a curing agent, and spraying the mixture on the surfaces of wood shavings or fibers or coating the mixture on the surfaces of veneers according to a certain proportion; and then hot-pressing the glued fibers, shavings or veneers according to certain hot-pressing conditions to form the artificial board.

7. The method for preparing artificial board by using the phosphorus-aluminum aldehyde-free adhesive for artificial board according to claim 6, wherein the method comprises the following steps: the curing agent is magnesium oxide, aluminum oxide, copper oxide, zinc oxide, iron oxide or aluminum nitride.

8. The method for preparing artificial board by using the phosphorus-aluminum aldehyde-free adhesive for artificial board according to claim 6, wherein the method comprises the following steps: the glue application amount of the fiber and the wood shavings is 8-30% of the absolute dry mass of the prepared artificial board, and the veneer is 300g/m of 100-²And (4) performing double-sided sizing.

9. The method for preparing artificial board by using the phosphorus-aluminum aldehyde-free adhesive for artificial board according to claim 6, wherein the method comprises the following steps: the hot pressing temperature of the fiber and the wood shavings is 150-200 ℃, the hot pressing time is 0.5-2min/mm, and the hot pressing pressure is 0.5-2.0 MPa; the hot pressing temperature of the single board is 150-200 ℃, the hot pressing time is 0.5-2min/mm, and the hot pressing pressure is 0.5-2.0 MPa.

Technical Field

The invention relates to the technical field of artificial board adhesives, in particular to a preparation method of a phosphorus-aluminum inorganic adhesive for artificial boards.

Background

With the increasing concern of people on environment and ecology, many researchers find inspiration from nature and apply the green concept to life. Wood and wood composites are renewable, degradable, environmentally friendly materials that have been widely used in homes and public places. The wood products such as shaving board, plywood and medium density fiberboard are most widely used. The wood material needs a large amount of adhesive in the production and use processes, and the formaldehyde-based adhesive has the largest using amount, low cost, high activity and good binding power to the wood material. However, these formaldehyde-based adhesives release formaldehyde under certain conditions. Formaldehyde is a dangerous genotoxic substance that is classified as a human carcinogen by the U.S. environmental protection agency. To solve this problem, non-formaldehyde-based adhesives, such as wheat flour, lignin, starch, soy protein, polyvinyl acetate, and the like, have been extensively studied for the preparation of formaldehyde-free adhesives. However, in practical application, these adhesives also have the defects of poor wet strength, poor corrosion and mildew resistance, insufficient bonding strength and the like.

Phosphoric acid based adhesives are the products of the reaction of phosphoric acid solutions with metal oxides such as magnesium oxide, aluminum oxide, iron oxide. The phosphorus-aluminum adhesive as a phosphate-based adhesive has the advantages of no aldehyde, low raw material cost, wide source and the like. After being cured, the phosphorus-aluminum adhesive can form a continuous chain structure or a three-dimensional net structure, and the structure can ensure that the bonded objects have high strength. Meanwhile, the phosphorus-aluminum adhesive has good thermal stability, is antibacterial and anticorrosive, and has a long service life. The phosphoaluminate adhesives have also been used as heterogeneous catalysts to convert biomass materials into hydrocarbons, as ceramic coatings for metal or concrete outer layers, as structural adhesives for rockets or other high temperature oxidizing and corrosive environments. However, the phosphor-aluminum inorganic composite has not been used as an adhesive for wood-based composite materials.

The invention aims to prepare a phosphorus-aluminum adhesive for an artificial board without formaldehyde release by using phosphoric acid and aluminum hydroxide.

Disclosure of Invention

The invention aims to provide a method for preparing a phosphorus-aluminum adhesive for an artificial board aiming at the defects of the prior art. The artificial board prepared by the invention has better mechanical, flame retardant and mildew proof properties.

In order to realize the purpose of the invention, the invention adopts the following technical scheme:

a preparation method of a phosphorus-aluminum formaldehyde-free adhesive for artificial boards comprises the following steps:

(1) taking phosphoric acid solution or hydrogen phosphate solution with certain concentration and an aluminum compound as raw materials, wherein phosphorus and aluminum elements form a certain phosphorus-aluminum ratio, and the solid content of the adhesive is designed;

(2) heating a phosphoric acid solution or a hydrogen phosphate solution in water bath, and then adding an aluminum compound to react for a period of time;

(3) and adding a polyvalent metal salt or a polyvalent metal oxide and a boride into the solution, continuously reacting for a period of time, and cooling to obtain the phosphorus-aluminum formaldehyde-free adhesive for the artificial board.

The hydrogen phosphate in the step (1) comprises one of soluble dihydrogen phosphate and soluble monohydrogen phosphate; the aluminum compound comprises one of aluminum hydroxide, aluminum oxide and aluminum nitride; the phosphorus-aluminum ratio is the molar ratio of phosphorus element to aluminum element, and ranges from 2.0:1 to 4.0: 1; the solid content of the adhesive is 40-85%.

The water bath temperature in the step (2) is 50-150 ℃, and the reaction time is 20-300 min.

The polyvalent metal salt and the polyvalent metal oxide in the step (3) are salts and oxides consisting of Zn, Mg, Fe, Cu and Cr, and have the functions of increasing nodes of an inorganic network and improving the bonding strength of the adhesive; the boride is borax or boric acid; the reaction time is 20-120 min.

The viscosity of the phosphorus-aluminum formaldehyde-free adhesive for the artificial board is 30-600 mPa.S.

The method for preparing the artificial board by using the phosphorus-aluminum formaldehyde-free adhesive for the artificial board comprises the following steps: uniformly mixing a phosphorus-aluminum formaldehyde-free adhesive for the artificial board and a curing agent, and spraying the mixture on the surfaces of wood shavings or fibers or coating the mixture on the surfaces of veneers according to a certain proportion; and then hot-pressing the glued fibers, shavings or veneers according to certain hot-pressing conditions to form the artificial board.

The curing agent is magnesium oxide, aluminum oxide, copper oxide, zinc oxide, iron oxide or aluminum nitride.

The glue application amount of the fiber and the wood shavings is 8-30% of the absolute dry mass of the prepared artificial board, and the veneer is 300g/m of 100-²And (4) performing double-sided sizing.

The hot pressing temperature of the fiber and the wood shavings is 150-200 ℃, the hot pressing time is 0.5-2min/mm, and the hot pressing pressure is 0.5-2.0 MPa; the hot pressing temperature of the single board is 150-200 ℃, the hot pressing time is 0.5-2min/mm, and the hot pressing pressure is 0.5-2.0 MPa.

Compared with the prior art, the invention has the beneficial effects that:

(1) the invention improves the relevant physical and chemical properties of the prepared product, such as good mechanical strength, mildew resistance, corrosion resistance and the like, for the formaldehyde-free phosphorus-aluminum adhesive for the artificial board; particularly, the flame retardant property is obviously enhanced, and the flame retardant grade reaches B2 grade specified in the building interior decoration design fire standard;

(2) the product has the advantages of abundant raw material sources, low cost, simple production process, no pollution, no environmental pollution caused by waste, natural degradation, and less smoke generation in the combustion process.

(3) Compared with the existing phosphorus-aluminum-based adhesive, the product has the advantages of low viscosity, low curing temperature, flame retardance, mildew resistance and the like. Meanwhile, the product is cured in a thermosetting mode in the production process of the artificial board, and compared with other phosphate adhesives (cold-pressing curing) used in the field of artificial boards, the product has the characteristics of continuous production, short production period and high production efficiency.

Detailed Description

In order to make the present invention more comprehensible, the technical solutions of the present invention are further described below with reference to specific embodiments, but the present invention is not limited thereto.