Production method of anti-corrosion and flame-retardant laminated veneer lumber

Abstract

The invention provides a method for producing veneer laminated timber with corrosion resistance and flame resistance. Between a preparation step of a veneer and a gluing step of the veneer in the conventional production method, a step of performing compound modification treatment on the veneer is added and comprises the following contents of: preparation of a compound modification agent: uniformly mixing alkaline copper quaternary (ACQ) preservatives and phosphorus-nitrogen flame retardant according to the weight ratio of 1:2 to 2:1, and adjusting the pH value of the compound modification agent to 10-11 by sodium hydroxide solution with concentration of 10% to 20%; and impregnated modification treatment: impregnating the veneer into the compound modification agent prepared in the first step for 1 hour to 10 hours at a room temperature and in a constant pressure environment, and drying the veneer at a temperature of 50-70 DEG C until the absolute moisture content of the veneer is 6% to 8% after the impregnation is finished. By the preparation of the creative compound modification agent and the impregnated modification treatment, the problem that the preservatives, the flame retardant and an adhesive cannot be compatible well in the prior art can be solved, and the veneer laminated timber with good mechanical, corrosion resistant and flame-retardant properties can be produced.

Description

technical field [0001] The invention relates to the technical field of wood-based panel manufacturing, in particular to a production method of laminated veneer strips. Background technique [0002] With the development of outdoor wood products and wood structure buildings, the domestic demand for engineered wood products such as laminated veneer lumber (LVL), laminated veneer lumber (PSL), and glued wood (Glulam) is increasing. big. The particularity of outdoor use requires that engineered wood products not only have high mechanical properties, but also require high anti-corrosion and flame-retardant properties. In areas where termites are severe, indoor wood products also need to have anti-corrosion and flame-retardant properties to prevent termite damage. Laminated veneer lumber is a new type of wood composite material formed by oriented veneer strips along the length direction of wood fibers. It has the advantages of high mechanical properties and stable performance. It...

AI Technical Summary

Problems solved by technology

[0003] In the prior art, there are three types of methods for anti-corrosion and flame-retardant modification of wood-based panels. The first type: adding a small amount of modifier to the adhesive. This method is simple to operate, but there are two disadvantages Defects, one is that the modification effect is not obvious due to the small amount of modifier used; the other is the incompatibility between the adhesive and the modifier—whether it is a single ACQ preservative or phenolic resin adhesive Mixed or single phosphorus-nitrogen flame retardants mixed with phenolic resin glue will produce precipitation and incompatibility problems, which will seriously affect the modification effect

The second category: After the semi-finished product is processed, the entire semi-finished product is treated with a modifier, such as impregnated with preservatives, etc. This method requires the performance of the semi-finished product to be high, and there are defects such as difficult impregnation of the modifier and uneven impregnation that affect the modification effect.

[0004] For veneer-based wood-based panels, a single anti-corrosion or flame-retardant modification treatment is performed separately, that is, the veneer is respectively dipped in a single anti-corrosion agent or flame retardant for modification, and only a single anti-corrosion or flame-retardant modification effect can be obtained. , cannot meet the multi-faceted requirements of anti-corrosion and flame-retardant of veneer wood-based panels at the same time

At the same time, the anti-corrosion and flame-retardant modification of veneer-based wood-based panels is carried out. Due to the compatibility problems between modifiers such as preservatives and flame retardants, as well as between modifiers and adhesives, As a result, chemical reactions between them will occur in advance, resulting in precipitation, which seriously affects the modification effect

At present, there is a solution that divides the flame retardant and anti-corrosion modification of the veneer into two parts, which are carried out separately, but this will also lead to the loss of the modifier, thereby affecting the modification effect; another method is to divide the veneer One-time impregnation of dual-function modifiers, such as boric acid, is easy to operate and has two functions of corrosion resistance and flame retardancy. However, the modifier used in this method is easy to precipitate and lose after modification treatment, and the modification effect is relatively low. Difference

In the prior art, there is no method capable of reliably performing anti-corrosion and flame-retardant modification treatments on veneer strips at the same time, and then producing anti-corrosion and flame-retardant laminated veneer lumber