Each has its own merits! Do you know the difference between coupling agent, cross linking agent and compatibilizer?
The difference between coupling agent and crosslinking agent:
Cross-linking agents generally refer to a class of chemicals that participate in the cross-linking reaction of resins to connect active functional groups in the resin to form a network structure. The cross-linking agent can mainly improve the viscosity and elasticity of the working fluid. At the same time, it should also have certain temperature and salt resistance properties according to the geological characteristics of the reservoir. In addition, some additives will be added to improve the overall performance of the working fluid.
Coupling agents generally refer to small molecular chemicals containing 3 or more hydrolyzable carbon functional groups. Using a small amount can improve the well-known adhesion of organic and inorganic materials, the reactivity of hydrolyzable groups and carbon. The group can be fixed on the surface of any organic material, that is to say, it can form a bridge between the resin and the interface, increase the adhesion of coatings and adhesives, and use less amount.
The difference between the two is not very big, and the coupling agent is a class of substances with two functional groups of different properties. Some functional groups in their molecules can react with adsorbed water or hydroxyl groups on the surface of inorganic substances, and some functional groups can react with organic molecules to form bonds or couplings. There is little difference between cross-linking agents and bridging agents, both of which can make linear molecules cross-link each other into a network structure.
Cross-linking agents are mainly used in polymer materials, because the molecular structure of polymer materials is like a long line. Without cross-linking, the strength is low, it is easy to break, and there is no elasticity. The function of the cross-linking agent is linear. Chemical bonds are generated between the molecules, so that the linear molecules are connected to each other to form a network structure, which improves the strength and elasticity of the rubber. The crosslinking agent used in the rubber is mainly sulfur, and an accelerator is added.
The difference between coupling agent and compatibilizer:
In a sense, both are surfactants with different uses.
1. Coupling agent is mainly used between inorganic and organic, the main function is to improve the compatibility between filler and resin molecular chain, high dispersion of filler in resin, such as silane and titanate coupling agent ;
2. The compatibilizer is used to improve the compatibility between the blended polymers, that is, the compatibility between two different resins in the polymer alloy is usually polyolefin grafted maleic anhydride produced by reactive extrusion. GMA and other reactive grafts, as well as synthetic polar polymers.
Effective time of coupling agent:
The environment in which the coupling agent is used such as humidity, storage time, ink and coating formulation and pH value, etc. Most titanates and silanes are weakly alkaline, and decompose into alcohols by hydrophilicity. Their effect is poor in wet and rainy seasons in the south, and it takes longer to dry in the north. It is also necessary to check whether the spray interface is weakly acidic or acidic. Common There are nothing more than three series of KH (silane), A (titanate) and N (azo), which are reactive to water, alcohol, ether, ammonia, amine and acid and lose coupling ability after reaction, For long-term storage, attention should be paid to avoiding oxygen and checking frequently.