1How to explain the blistering phenomenon of fireproof board after gluing?
The fireproof board has good compactness. After pasting, the organic solvent that has not evaporated in the glue will continue to volatilize and accumulate in the local area of the board. When the accumulated pressure reaches a certain level after 2 to 3 days, the fireproof board will be lifted up and formed Bubble (also known as bubbling). The larger the area of the fireproof board, the easier it is for blistering; if it is pasted in a small area, blistering is less likely to occur.
Reason analysis: ①The adhesive film is not dried before the panel and the bottom plate are bonded, resulting in the low adhesion of the universal adhesive film, and the volatilization of the solvent of the adhesive layer in the middle of the board causes the panel to bubble; ②The air is not discharged during pasting, and the air is wrapped. ③Uneven thickness when scraping the glue, causing the solvent in the thick area to not evaporate completely; ④Lack of glue in the board, resulting in no glue or little glue in the middle when bonding on both sides, small adhesion, and a small amount of solvent that has not evaporated The air pressure formed in the volatilization destroys the bonding; ⑤ In humid weather, the adhesive film reduces the viscosity due to moisture absorption, and the adhesive layer is considered to be dry but not actually dry.
Solution: ①Extend the drying time so that the solvent and water vapor in the film are completely volatilized; ②When sticking, try to roll to one side or from the middle to the surrounding to exhaust the air; ③When scraping the glue, try to have a uniform thickness and no lack of glue; ⑥Yes Drill a number of air holes on the bottom plate to increase air permeability; ⑦The film is heated by heating to increase the activation temperature.
2 After a period of time, the universal glue will appear warped and cracked in the glue layer. How to solve it?
Reason analysis: ①The corners are coated with too thick glue, which causes the glue film to not dry; ②The corners lack glue when glue is applied, and there is no glue film contact when sticking; ③The initial adhesion force is not enough to overcome the elasticity of the plate when sticking in the arc position; Insufficient effort.
Solution: ①Spread the glue evenly, and appropriately extend the drying time for curved surfaces, corners, etc.; ②Spread the glue evenly, and pay attention to the lack of glue at the corners; ③Appropriately increase the pressure to make the fit tightly.
3 It does not stick when using universal glue, and the board is easy to tear off, why?
Reason analysis: ①After applying glue, it is pasted before the solvent in the glue film evaporates, causing the solvent to be sealed, the glue film is not dry, and the adhesion is extremely poor; ②The glue is dead, and the glue drying time is too long, which causes the glue film to lose its viscosity; ③Board Loose glue, or there is a large gap when glue is applied and lack of glue, or pressure is not applied, causing the bonding surface to be too small, resulting in low adhesion; ④Single-sided glue, the adhesive force after the film is dry is not enough to adhere Glue-free surface; ⑤ The board is not cleaned up before gluing.
Solution: ①After applying glue, wait until the film is dry (that is, when the film is sticky without sticking to the finger touch); ②Spread the glue evenly without lack of glue; ③Spread the glue on both sides; ④Stick After closing, roll or hammer to make the two sides contact closely; ⑤Clean the bonding surface before applying glue.
4 When used in winter, neoprene universal glue is easy to freeze and not stick. Why?
Reason analysis: chloroprene rubber belongs to crystalline rubber. As the temperature decreases, the crystallinity of the rubber increases, and the crystallization speed becomes faster, resulting in poor viscosity and shortened viscosity retention time, which is prone to poor adhesion and inability to stick; At the same time, the solubility of chloroprene rubber decreases, which is manifested as an increase in the viscosity of the glue until it gels.
Solution: ① Put the glue into hot water at 30-50 degrees Celsius for a long enough time, or use heating tools such as a hair dryer to heat the glue film; ② Try to avoid the shaded surface and choose to construct when the temperature is high at noon.
5 In humid weather, the surface of the film is easy to turn white after the sheet is glued. Why?
Reason analysis: Universal glue generally uses fast-drying solvents. The rapid volatilization of the solvent will take away heat and make the surface temperature of the film drop rapidly. In humid weather (humidity>80%), the temperature of the film surface is very high. It is easy to reach below the “dew point” of water, causing moisture to condense on the glue layer, forming a thin water film, that is, “whitening”, which hinders the progress of bonding.
Solution: ①Adjust the solvent ratio to make the solvent volatilization gradient uniform. For example, appropriately increase the content of ethyl acetate in the glue to take away the moisture above the glue layer during volatilization to prevent the formation of a water film on the glued surface and protect it. Function; ②Use a heating lamp to heat and drive away moisture; ③Extend the drying time to make the water vapor fully volatilize.
6 The soft PVC material cannot be stuck with universal glue, why?
Reason analysis: Because the soft PVC material contains a large amount of ester plasticizer, and the plasticizer is a non-drying grease, it is easy to migrate to the surface of the substrate and mix into the glue, causing the glue layer to become sticky and unable to solidify .
7 Universal glue is thick when used, does not open when brushing, and tends to form a lump, how to solve it?
Reason analysis: ①The sealing of the package is not ideal, and the solvent has evaporated; ②When the glue is used, it will be left open for too long, which will cause the solvent to evaporate and thicken; ③The solvent will evaporate too fast and cause the surface conjunctiva.
Solution: You can add the same effective diluent such as solvent gasoline, ethyl acetate and other solvents to dilute, or consult the relevant professional and technical personnel of the company.
After 8 universal glue is applied, there are bubbles on the surface of the film, what’s the matter?
Reason analysis: ①The board is not dry, which is more common in the splint; ②There are impurities such as dust on the board, which cause mixing in the glue; ③The scraping of the glue is too fast and the air is wrapped.
Solution: ①For wood products such as plywood, floor, plywood, etc., the adherend contains water, and it should be properly dried or dried before use; ②The substrate should be cleaned before use; ③The speed of squeegee is appropriate.
How to solve the problem if the film does not dry for a long time when using the universal glue?
Reason analysis: ①The glue is not suitable for the substrate, such as bonding PVC materials; ②The non-drying oil such as plasticizer is mixed into the universal glue; ③The low temperature of the construction environment causes the solvent to evaporate slowly.
Solution: ①For unknown materials, they must be tested before they are used; ②Reduce or eliminate plasticizers; ③Appropriately extend the drying time, or use heating tools to improve, so that the solvent and water vapor in the film will completely evaporate.
How to estimate the amount of 10 universal glue?
Estimation method: The larger the painting area of the universal glue, the better. If the glue is too thin, it is easy to cause the bonding strength to decrease. In severe cases, it will lead to lack of glue, failure to stick or glue falling. When pasting, 200g～300g of glue should be applied to the sticking surface and the sticking surface, one square meter should be coated with 200g～300g glue, a bucket of glue (10kg) can be coated with 40～50m², and a sheet area of 1.2*2.4 meters can be pasted about 8 Sheets.
11How to master the drying time of universal glue?
Gluing skills: Universal glue is a solvent-based rubber adhesive. After coating, it needs to be left in the air until the solvent has evaporated before it can be pasted. It is very important to grasp the drying time during construction. Pay attention to the following points: ① “The film is dry” and “Not sticky to the hand” means that the film is sticky when the film is touched by the hand, but it is not sticky when the finger is left. If the adhesive film is not sticky at all, the adhesive film has dried out in many cases, loses its viscosity, and cannot be bonded; ②In winter or humid weather conditions, the moisture in the air tends to condense on the surface of the adhesive to form white Fog reduces the adhesion, so you must wait until the glue layer solvent is completely volatilized before sticking. If necessary, heating equipment can be used to improve this phenomenon and prevent blistering or falling off.
12How to choose universal glue when decorating?
Adhesive selection method: ①Understand the properties of the adhesive: Universal glue can be divided into two types: neoprene and SBS based on its composition; neoprene universal glue is characterized by strong initial adhesion, good firmness, good durability, but smell Larger and higher cost; SBS type universal glue is characterized by high solid content, low odor, environmental protection, and low cost, but the bonding strength and durability are not as good as neoprene type. It is generally used indoors and some less demanding Occasion; ②Recognize the nature of the adherend: common decoration materials, such as fireproof board, aluminum-plastic board, paint-free board, wood plywood, plexiglass board (acrylic board), glass magnesium board (gypsum board); some difficult-to-stick materials It is not suitable to use all-purpose adhesives, such as polyethylene, polypropylene, polytetrafluoroethylene and other polyolefins, organic silicon, and snow iron. Plasticized PVC, plastics containing a large amount of plasticizers, and leather materials; ③Considering the conditions of use, such as temperature, humidity, chemical media, outdoor environment, etc.
Post time: May-17-2021