Organic phosphines , metal phosphine complexs
OLED intermediates "/>
Application of curing agent in epoxy resin industryApplicationof curing agent in epoxy resin industry Many users will ask merchants to distribute morecuring agent when buying epoxy floor paint, because they feel that as long asmore curing agent is put in, the curing speed of epoxy floor can beaccelerated, thereby shortening the construction time. In fact, this is anunrealistic approach. On the contrary, when more curing agent is added, thecuring speed is actually slower, and there may even be cases of non-curing. Whyis this? Due to the deviation of the literal understanding ofthe "curing agent" of epoxy paint, many people will understand thecuring agent as an auxiliary agent to help the epoxy resin cure. As long as thecuring agent is added, the epoxy resin will be cured into a floor, as long asIf enough curing agent is added, the curing speed will be faster. Thisunderstanding is wrong! If we name the curing agent "epoxy floor paintcuring reaction agent", we can clearly understand the relationship betweencuring agent and epoxy resin. As the name implies, the curing agent is apreparation that participates in the curing reaction. The difference is thatthe curing agent is a constituent substance that participates in the curingreaction. It is an indispensable part of the film formation of the epoxy floorpaint and cannot be simply understood as promoting auxiliary agent for curing. The reactionprocess of epoxy resin and curing agent is a process of chemical reaction.After the epoxy resin is evenly mixed, the hydroxyl group in the resin willfirst be opened from the closed state, and then recombined with thehydrogen-oxygen bond in the curing agent to form a new closed loop. This newclosed-loop cross-interconnection forms a solid three-dimensional structure.The new structure is in a very stable state. This state gives the epoxy floorpaint strong mechanical properties and chemical resistance, which is good fordaily damage or chemical resistance. The curing agentplays the role of promoting curing in the whole process, and at the same timeit is an important part of the final paint film after curing. If it is simplyunderstood as an accelerator, then there is no way to explain how the epoxyresin reaches the liquid state. The process of conversion to curing cannotexplain why the epoxy paint film after curing can have such a high strength. What happens ifthe curing agent is added too much or too little? Since the curingprocess is a chemical reaction process, there must be a problem of the ratio ofthe quality of the reaction components. Only when the epoxy make resin and thecuring agent reach the equilibrium state can the curing reaction be sufficientand appropriate. We can imagine that the number of ring-openings formed duringthe reaction is fixed, then the corresponding curing agent oxyhydrogen bond isneeded to link, this relationship locks the ratio of the two sides of thereaction. When there is toomuch curing agent, the ring-opening epoxy resin has been linked with enoughcuring components. The extra curing agent cannot find more ring-opening resin,so it can only be free in the epoxy resin in its original state in the paintfilm, when the curing agent is too little, the epoxy resin also cannot find thecuring component that can be linked, so it can only be free in the paint film.This is usually the case that cannot be cured. Too much or too little curingagent will affect the film formation quality. In addition,uneven stirring is also a serious problem affecting the curing reaction. Many users stillfail to cure after construction according to the manufacturer's matchingmaterials. This is a typical case of uneven mixing. The good reaction betweenthe resin and the curing agent requires the two materials to be properly mixedtogether. When the mixing is uneven, the two paint liquids cannot be wellfused, and the materials that are not in contact will not react, so they canonly maintain their original liquids. In the state, it means that the paintcan't be dried, or it can handle the sticky state for a long time. Speaking of which,it is estimated that everyone can understand the effect of the curing agent onthe epoxy floor paint! The curing agent is definitely not used to cure faster,but on the contrary, it will not only cure not fast, but also make the dryingvery slow or unable to dry. When using, the user must strictly follow theproportion of the manufacturer's formula, and must be thoroughly mixed andmixed before use, so as to ensure that no curing problems will occur during use. Puyang Huichengspecializes in the production of epoxy resin curing agents. Its main productsare tetrahydrophthalic anhydride, hexahydrophthalic anhydride,methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, nadicanhydride, methyl nadic anhydride, etc. Always adhering to the principle ofcustomer needs first, ensuring quality and ensuring long-term stable supply, ithas become the largest domestic production base of high temperature resistantcuring agent.
|