An important auxiliary material is indispensable in the production and processing of stone products. Adhesive is required for the repair of slab fracture; the repair of holes and cracks on the surface of the slab requires adhesive; the processing of stone composite panels requires adhesive; the bonding of stone products requires adhesive ; The installation and construction of stone products are also inseparable from adhesives. It is undeniable that the lack of adhesives makes the production, processing and construction of stone products difficult to achieve. Stone products cannot become important building materials. The production and processing of adhesive stone products and the decoration of buildings play an important role.
Adhesives are used every day in the production and processing of stone products, especially the production and processing of marble. The employees of stone production enterprises have to face all kinds of adhesives every day. When faced with so many adhesives, many employees are at a loss. Employees with long experience in the industry may not be able to make the right decision on the choice of adhesives, and know the classification and use of adhesives. It is very necessary to popularize this knowledge of adhesives, so that more employees of stone production enterprises can master this important substance in stone production and processing.
1. What is an adhesive?
 
Adhesives are divided into glue and adhesive.
 
The definition of glue is defined in "Baidu" as follows: glue is a substance that can bond two objects together and firmly connect the two objects together to form a whole. Glue does not exist independently, it must be applied between two objects to play a bonding role. The bonding of objects is achieved by the tension between the polymers in the glue. In the glue, water is the carrier of the medium polymer, and the water carries the polymer and slowly immerses into the tissue of the object. When the water in the glue disappears, the polymer in the glue will rely on mutual tension to bind the two objects together tightly.
 
In the use of glue, if the amount of glue is too much, the polymers in the glue will be crowded together, and there will be no good tension between the polymers. At the same time, the moisture between the polymers is not easy to evaporate. This is why in the bonding process "the thicker the film, the worse the bonding effectiveness of the glue". If the amount of glue is too much, the glue plays a "filling effect" rather than a bonding effect. The adhesion between objects does not rely on the adhesive force of the glue, but the "cohesion" of the glue.
 
The definition of adhesive is defined in "Baidu": Any medium that can connect the surfaces of the same or different solid materials together is collectively called an adhesive. The method of connecting the solid surfaces together through the adhesive force of the adhesive It is called bonding or gluing. Adhesives are used in a wide range of applications. The manufacturing and installation of stone products, aircraft manufacturing, automobile manufacturing, aerospace aircraft, shipbuilding, furniture manufacturing and other industries require a large number of adhesives. Adhesives are inseparable from our lives and production. Figure 2 shows dry hanging glue for stone.
2. Classification of stone glue
 
The classification of stone glue includes glue and adhesive. 502 glue is used to repair some powdery and granular materials in the stone production and processing, and temporarily fix the stone when bonding; marble glue, dry hanging glue, and waterproof adhesive are adhesives, which are widely used in stone repair and bonding Processing is a very widely used processing auxiliary material for stone.
 
 
(1) 502 glue
 
502 glue is mainly α-cyanoethyl acrylate, adding tackifiers, stabilizers, toughening agents, polymerization inhibitors, etc., through the advanced production process synthesis of one-component instant curing and adhesion, can stick to the largest Most substances of various materials. If the 502 glue is exposed and placed in contact with a small amount of water vapor in the air, it will be catalyzed and rapidly polymerized and solidified and adhered, so it is called an instant adhesive.
(2) Unsaturated resin glue
 
Unsaturated resin glue refers to a polyester polymer with unsaturated bonds in the molecular chain, which is the main material for stone slab glue reinforcement and artificial stone processing. Unsaturated dibasic acid, saturated dibasic acid and diol undergo polycondensation reaction under certain conditions to form unsaturated polyester. The unsaturated polyester is dissolved in a certain amount of crosslinking monomer to form a liquid resin, which is an unsaturated resin.
 
Unsaturated resin glue includes artificial marble unsaturated resin glue, quartz stone unsaturated resin glue, marble unsaturated resin glue, handicraft unsaturated resin glue, coating resin glue and so on.
 
The use of unsaturated resin glue in stone processing: mainly used for repairing glue on the surface of large slabs, reinforcing the fiber net behind the stone, and manufacturing artificial stone and quartz stone. Figure 4 Unsaturated resin glue
(3) Epoxy resin glue
 
Epoxy resin generally refers to a polymer ring containing two or more epoxy groups, taking aliphatic, alicyclic or aromatic organic compounds as the skeleton, and forming useful thermosetting products through the reaction of epoxy groups Oxygen oligomers. It has three material forms: liquid, sticky state, and solid state. The physical and chemical properties of epoxy resin glue are better than unsaturated resin glue, with good permeability, high bonding strength and good weather resistance. The quality of repaired board is better than unsaturated resin glue. Epoxy resin glue stone production enterprises are mostly used for high-end stone repair and countertop processing.
 
Epoxy resin is widely used in the repair of stone slabs, especially high-grade jade stone, beige stone and crystal stone. Epoxy resin glue has high permeability, high adhesion and high strength. Although the price is higher than 1/3 of resin glue, it is welcomed by most stone production enterprises.
 
 
(4) Marble glue
 
Marble gum is a polymer composed of unsaturated linear polyester resin produced by unsaturated dibasic acid and diol and polymerizable monomer, which is an unsaturated polyester resin (UP). Its solidification speed is fast, but the weather resistance, anti-aging performance, waterproof and moisture resistance ability after curing and mechanical strength are far lower than dry-hanging stone epoxy adhesive (AB glue, dry-hanging glue), so it cannot be used for stone construction and installation middle.
 
The use of marble glue: mainly used for stone fracture repair, surface repair, temporary fixation of stone product bonding, filling of stone surface holes, stone reinforcement, and glass rod reinforcement. Figure 5 Marble glue.