Industry grade Electronic grade 99% N-Methyl-2-pyrrolidone CAS 872-50-4 NMP

What is N-Methyl-2-pyrrolidone? How does it work?

N-Methyl-2-pyrrolidone (NMP, also known as 1-methyl-2-pyrrolidone), with the chemical formula C5H9NO, is a five-membered lactam organic compound. At room temperature, it is a colorless, transparent liquid (impure forms a pale yellow color). It is almost infinitely miscible with water and most common organic solvents, belonging to the class of strongly polar aprotic solvents (similar to dimethylformamide (DMF) and dimethyl sulfoxide (DMSO)). It is a well-known "universal solvent" in industry—it dissolves binders in lithium-ion battery electrode slurries, peels off photoresists from chips, absorbs hydrogen sulfide in natural gas desulfurization, and removes coatings in paint removers.Annually, NMP is produced in the amount of around 200,000-250,000 tons and is used to support core industries such as new energy, electronics, petrochemicals and polymers, from electric vehicle batteries to mobile phone chips.

Basic information: Chemical formula C5H9NO (molecular weight 99.13); CAS number 872-50-4 (EC 212-828-1, ECHA 100.011.662), PubChem CID 13387, UNII JR9CE63FPM, ChEBI 7307; It belongs to the polar aprotic solvent class (similar to DMF and DMSO), with a five-membered lactam ring structure, with a strong dipole moment and hydrogen bond acceptance ability (cis amide conformation); Produced industrially by reaction of γ-butyrolactone with methylamine (ester-amine conversion), or by partial hydrogenation of N-methylsuccinimide, addition hydrolysis of acrylonitrile with methylamine, etc.

Physically, it is a colorless, transparent liquid; density approximately 1.028 g/cm³ (20℃); melting point approximately -24℃; boiling point approximately 202-204℃ (high boiling point, low volatility); flash point approximately 91℃; autoignition temperature approximately 245℃; completely miscible with water, soluble in common organic solvents such as ethanol, acetone, diethyl ether, ethyl acetate, chloroform, and benzene; strongly hygroscopic. Chemically, it belongs to the lactam compound family and is generally stable to acids, alkalis, and oxidizing agents; it reacts with phosphorus pentasulfide to form the corresponding thioamide; it undergoes reversible ring-opening with sodium hydroxide; and it can undergo hydrolytic ring-opening under high-temperature, strongly alkaline conditions.

From the perspective of its mechanism of action, NMP exerts multiple functions due to its strong polar solubility, high boiling point and low volatility, selective absorption, ultra-high purity and low pollution, and strong penetration ability. The mechanisms of action in different applications are as follows:

1. The core principle of highly polar universal dissolution mechanism.

NMP has a high dielectric constant, strong dipole moment and hydrogen bond acceptance capability, and a very wide range of solubility parameters. It can dissolve poorly soluble polymers such as PVDF, polyimide, polyphenylene sulfide, and aramid, as well as most resin and coating systems, making it a "universal solvent".

2. High boiling point and low volatility mechanism

With a boiling point of approximately 202°C and low vapor pressure, it is suitable for high-temperature polymerization reactions and coating and drying processes. It has low volatilization loss, is recyclable and reusable, and reduces the risk of fire and inhalation exposure (flash point 91°C).

3. Selective absorption mechanism

NMP has selective solubility for acidic gases such as hydrogen sulfide and unsaturated hydrocarbons such as butadiene and acetylene, and can be used for gas desulfurization and hydrocarbon extraction and separation (such as the Purisol process).

4. Photoresist swelling and peeling mechanism

NMP's strong polarity penetrates the photoresist polymer network, causing it to swell and expand in volume, thus disrupting the adhesion between the photoresist and the wafer interface. This allows the entire layer of cured photoresist to be peeled off without damaging the underlying metal and dielectric layers.

5. Ultra-high purity and low pollution mechanism

Electronic-grade NMP controls metal ions at the ppb level, and particles are filtered through submicron filters to prevent metal and particle contamination of the wafer, ensuring the electrical performance and yield of nanoscale devices.

6. Strong penetration and wetting mechanism

NMP has strong skin penetration and wetting capabilities, allowing it to penetrate the coating interface and cause it to swell and peel off. This is the basis for the function of paint removers and cleaning agents (and therefore strict protection is required).

In summary, N-methylpyrrolidone is a versatile solvent spanning new energy, electronics, and chemicals. Its strong polar dissolving power supports lithium batteries and high-performance polymers, its stripping and cleaning capabilities serve chip manufacturing, its selective absorption serves petrochemical desulfurization, and its penetration and swelling capabilities serve cleaning and paint removal. From electric vehicle batteries to mobile phone chips, it runs through the entire new energy, electronics, petrochemical, and polymer chains.

What are the uses of N-Methyl-2-pyrrolidone?

The applications of N-methylpyrrolidone cover lithium batteries, semiconductors, displays, packaging, PCBs, petrochemicals, coatings, inks, polymers, fibers, pesticides, cleaning agents, adhesives, synthetic leather, recycling, and analytical chemistry, as detailed below:

1. Lithium ion battery electrode slurry solvent (core application for new energy batteries)

Application Fields: Manufacturing of Lithium-ion batteries & New Energy Fields.

Related Products: Solvent for lithium iron phosphate cathode slurry , Solvent for ternary cathode slurry , Solvent for PVDF binder , Solvent for anode slurry , Battery electrode coating slurry , Lithium ion battery recycling agent etc.

Why it works for this purpose: NMP is the sole industrial solvent capable of effectively dissolving polyvinylidene fluoride (PVDF) binders, enabling the uniform dispersion of the active material, conductive agent and binder into a slurry for coating onto the current collector. Its high boiling point and low volatility assist in drying the coating and are vital key solvents in the manufacturing of lithium-ion batteries.

2. Photoresist stripping solution (core application in semiconductor manufacturing).

Applications: Semiconductor and integrated circuit manufacturing.

Related Products: Photoresist Stripper, Thick Film Photoresist Remover, Photoresist Stripper After Ion Implantation, Photoresist Remover After Dry Etching, Positive & Negative Resist Strippers, High Selectivity Photoresist Removers, etc.

How does it work for this application: Electronic grade NMP, because of its strong polarity, penetrates the photoresist network causing it to swell and peel off. It is the industry standard solvent for photoresist removal in multi-layer patterning processes for chips and does not contaminate the wafer after stripping because of its low particle count and ppb-level metal ions.

3. Wet wafer cleaning and resist remover (core application in semiconductor industry).

Application Areas: Semiconductors - wafer fabrication and process.

Related Products: Wafer cleaning solutions, Resist removers, Metal ion control cleaning solutions, Post-etching cleaning solutions, Post-CMP cleaning solutions, Pre-diffusion cleaning agents, High purity process cleaning solvents etc.

Why it works for this purpose: Electronic grade NMP has a strong dissolving power to remove organic matter and residues from the wafer surface, it is ultrahigh purity to prevent recontamination of metals and particles, and it has a high boiling point to support thermal cleaning processes. It is a major high purity solvent for wet wafer cleaning and resist stripping processes.

4. Solvents for flat panel display manufacture (display panel industry)

Application Areas: Liquid Crystal Display (LCD) and Organic Light Emitting Diode (OLED) manufacturing

Related products: LCD photoresist stripping solution, OLED photoresist stripping solution, array substrate cleaning solution, color filter production solvent, flexible OLED substrate processing solvent, display panel precision cleaning agent, etc.

Benefits for this application: Display panel manufacturing also requires photoresist stripping and substrate cleaning. The stripping efficiency and ultrahigh purity of electronic-grade NMP ensure the pattern quality and panel yield of processes such as TFT arrays and color filters.

5. Packaging and electronic assembly industries: Semiconductor packaging and electronic cleaning agents

Application Areas: Semiconductor Packaging, Microelectromechanical Systems (MEMS), Precision Electronic Assembly

Related Products: Cleaning solution for packaging substrate, cleaning agent for lead frame, cleaning solution for post chip mounting, cleaning agent for MEMS sensor manufacturing, residue removing solution for flux, cleaning agent for precision electronic components, cleaning solvent for wafer level packaging, etc.

Why it works for this purpose: Packaging and precision assembly processes require the removal of flux residue, organic contaminants and particulates. Electronic-grade NMP has excellent dissolving power and no metal residue, ensuring reliability of solder joints, device sealing and sensor sensitivity.

6. Solvents used in manufacturing of printed circuit board (PCB industry)

Uses: Manufacture of printed circuit board (PCB) and high density interconnect (HDI).

Corresponding products include dry film photoresist stripping solution, wet film stripping solution, PCB circuit post-development cleaning agent, solder mask stripping agent, PCB precision cleaning solution, high-density interconnect board manufacturing solvent, etc.

How does it work for this purpose? PCB pattern transfer uses dry/wet film photoresist. Electronic grade NMP effectively strips dry film and cleans up any residual circuitry. The low impurity level can prevent the circuit from corrosion and leakage, ensuring the accuracy and reliability of the high-density circuit board pattern.

7. Solvents for petrochemical extraction and gas desulfurization (petrochemical industry)

Application Areas: Petrochemical and Gas Processing Industries.

Related Products: Butadiene extractant, acetylene recovery solvent, solvent for extraction of aromatic hydrocarbons, desulfurization agent for natural gas and syngas (Purisol process), hydrolysis promoter for carbonyl sulfide, solvent for refining lubricating oil, refinery gas purification agent, etc.

Why it works for this purpose: NMP has a selective solubility for unsaturated hydrocarbons like butadiene and acetylene, so it can be used to extract and recover hydrocarbons. Cold NMP aqueous solution has a high selective absorption capacity for hydrogen sulfide and can promote the hydrolysis of carbonyl sulfide, so NMP is a solvent for the Purisol gas desulfurization process.

8. Coating solvents (coatings industry)

Applications: Coating industry.

Related Products: Solvents for polyurethane coatings; solvents for automotive original equipment paints and repair paints; wood coatings; industrial anti-corrosion paints; thinners for baking paints; film-forming aids for water-based coatings; etc.

How it works for this purpose: The strong dissolving power of NMP can dissolve resin systems such as polyurethane. It has high boiling point and low volatility which improves film leveling and gloss and prevents pinholes. It is a commonly utilized solvent and thinner for high performance coatings.

9. Ink and solvent for inkjet ink (sector of the ink industry)

Application fields: Ink, inkjet printing.

Corresponding products: Screen printing inks, gravure printing inks, inkjet ink solvents, electronic circuit board inks, ceramic decal inks, pigment dispersant carriers etc.

Why it works for that purpose: NMP can dissolve ink resins and pigment dispersion systems; it has a high boiling point that prevents nozzle clogging and rapid drying skinning during printing; it improves leveling and adhesion; and it is a solvent component for high performance inks and inkjet inks.

10. Field of polymer materials: Solvents for the synthesis of high-performance polymers

Application fields: engineering plastics, polymer materials.

Related Products: Solvent for polyimide (PI) synthesis and film production, Solvent for polyphenylene sulfide (PPS) polymerization, Solvent for polysulfone and polyethersulfone synthesis, Solvent for polyetherimide (PEI) polymerization, Solvent for liquid crystal polymer (LCP) synthesis, Reaction media for high-temperature resistant resins.

Why suitable for this application: NMP has a high boiling point (approx. 202°C) and is therefore suitable for high temperature polycondensation reactions. Its strong dissolving power maintains the homogeneity of the polymer solution and it is a classic solvent for polymerization and processing of high-temperature resistant polymers such as polyimide and polyphenylene sulfide.

11. High performance fiber spinning solvent (industry of fiber)

Uses: High performance fiber field.

Corresponding products: Solvents for polymerization and spinning of para-aramid (Kevlar, Twaron), spinning solvents for polyimide fibers, processing solvents for meta-aramid, spinning media for ultra high molecular weight polymers, processing solvents for carbon fiber precursor etc.

Why it is appropriate for this application: Para-aramid polymerization is carried out by the liquid crystal solution polymerization and dry-jet wet spinning in an NMP/calcium chloride system. NMP is a homogeneous polymerization medium and satisfies the requirements of spinning and fiber formation, and thus becomes an indispensable process solvent for high-performance fibers such as aramid.

12. Industrial cleaning agents and paint removers (cleaning and surface treatment)

Uses: Industrial cleaning, surface treatment.

Related Products: Paint remover (alternative to dichloromethane), graffiti remover, precision cleaner for electronic components, mold cleaner, equipment maintenance cleaner, oil stain remover, paint remover for building renovation, etc.

Why it works for this purpose: NMP has good penetration and swelling ability which can penetrate the interface between paint film and coating resulting in swelling, wrinkling and shedding off the substrate. It also has a higher flash point and lower toxicity than Dichloromethane, which makes it a key component in environmentally friendly paint removers and industrial cleaning agents.

13. Adhesive solvents (adhesive industry)

Application fields: Adhesives and sealants.

Related Products: Polyurethane Adhesive Solvents, Leather and Footwear Adhesives, Automotive Interior Adhesives, Sealant Thinners, Structural Adhesive Reaction Media, Pressure Sensitive Adhesive Co-solvents etc.

How it works for this purpose: NMP is a solvent for polyurethane and other adhesive resins, adjusts viscosity and open time, and its high boiling point delays evaporation to give a long bonding window; it is a solvent component in high-performance adhesives.

14. Solvents for processing of synthetic leathers and artificial leathers (synthetic leather field)

Application Areas: Synthetic leather and artificial leather production.

Related Products: Solvents for processing of polyurethane synthetic leather (PU leather), solvents for wet coagulation bath for artificial leather, solvents for dry PU topcoat, solvents for processing of imitation leather fabric, solvents for processing of automotive interior leather, shoe leather and bag leather, etc.

How it works for this purpose: In the making of PU synthetic leather, NMP dissolves polyurethane resin to form a slurry which is then used to form a film through wet/dry processes. It has high boiling point and solubility, which can form a uniform and dense film layer. It is a key solvent for the processing of synthetic leather.

15. Recycling of plastic solvents (circular economy sector)

Application Fields: Plastic Recycling and Circular Economy.

Corresponding products: solvent for dissolution and recovery of polystyrene (PS) foam; chemical solvent for the recovery of polyurethane (PU) foam; solvent for purification of recycled polymers; ABS plastic recycling agent and dissolving medium for sorting of mixed plastics.

How it works: NMP can selectively dissolve target plastics, including polystyrene and polyurethane, leaching them from mixed waste for purification and recycling. This is the main solvent used in the chemical recycling of plastics.

16. Analytical Chemistry and Laboratory Solvents (Chemistry Analytical)

Applications: Analytical chemistry, laboratory testing.

Related Products: HPLC solvents, Solvents for gas chromatography injections, Solvents for liquid chromatography-mass spectrometry (LC-MS), Solvents for extraction and separation, Solvents for organic production reactions, Solvents for polymer dissolution and analysis, Solvents for spectroscopic analysis.

Why it is suitable for this application: High purity NMP has strong dissolving power, low UV absorption and is chemically inert, therefore it is suitable as chromatographic mobile phase, sample dissolution and extraction solvent to support analytical testing in the fields of polymers, petrochemicals and materials.

Summary

N-methyl-2-pyrrolidone (NMP) (C5H9NO, CAS 872-50-4) is a versatile solvent used in new energy, electronics and chemical industries. It has high polarity, high boiling point, low volatility, selective absorption, photoresist swelling and stripping mechanisms, ultrahigh purity, low pollution, and strong penetration, and has extensive applications as lithium-ion battery electrode slurry solvents, photoresist stripping solutions, wafer wet cleaning and resist removers, flat panel display panel manufacturing solvents, semiconductor packaging and precision electronic cleaning agents, printed circuit board (PCB) manufacturing solvents, petrochemical extraction and gas desulfurization solvents, coating solvents, ink and inkjet ink solvents, high-performance polymer synthesis solvents, high-performance fiber spinning solvents, industrial cleaning agents and paint removers, adhesive solvents, synthetic leather and artificial leather processing solvents, plastic chemical recycling solvents, and analytical chemistry and laboratory solvents . The two major applications are lithium-ion battery slurry solvents and photoresist stripping.