Basic introduction to NMP
NMP, full name N-methylpyrrolidone, molecular formula C5H9NO, a colorless transparent liquid, is one of the most commonly used lithium battery accessories. When making electrode sheets, NMP is used as a solvent to fuse various materials required for electrodes, such as binder, positive active substance, conductive agent, etc., so that the binder is fully in contact with other substances and evenly distributed. As a high-boiling solvent with excellent properties, NMP is completely mixed with almost all solvents (ethanol, acetaldehyde, ketones, aromatic hydrocarbons, etc.). NMP is a polar solvent with strong selectivity and good stability. It has the characteristics of high boiling point, strong solubility, good stability, biodegradable, recyclable, etc. It is widely used in lithium batteries, polymer materials, electronics, cleaning agents, medicine, pesticides, pigments and other industries, among which NMP has the largest application scale in the lithium battery industry.
NMP products have the characteristics of high boiling point, strong polarity, low viscosity, strong dissolution ability, no corrosion, little toxicity, strong biodegradation ability, low volatility, excellent chemical stability and thermal stability.
NMP is a special chemical product, according to metal impurities, control particle size, particle number and application range is divided into four grades, respectively, micro electrical grade, electronic grade, pharmaceutical grade and industrial grade. Among them, the micro-electric level requires the highest level, which is used in the cleaning of photoresist and liquid crystal packaging in integrated circuits; The electronic grade can be used in new materials such as lithium-ion batteries and aramid.
NMP is still in the growth stage in the domestic market, especially with the rapid development of the new energy vehicle market, which will promote the steady growth of the market demand for NMP.
According to the source, NMP can be divided into synthetic NMP and recycled NMP. Synthetic NMP refers to a new product prepared by chemical synthesis. Recovered NMP refers to the recycled products of NMP used as a solvent after recovery and refining.
In the synthesis of NMP, most manufacturers use 1, 4-butanediol (BDO) dehydrogenation to GBL, and then ammoniation and condensation to produce NMP. Others, such as Mitsubishi Chemical, use maleic anhydride hydrogenation to produce GBL, then ammoniation and condensation to produce a crude product, and then rectification and purification to the finished NMP.
