For professionals in chemical procurement and product development, understanding the precise specifications of industrial chemicals like Polymethylene Polyphenyl Polyisocyanate (PMDI) is crucial for successful sourcing and application. PMDI, with its CAS number 9016-87-9, is a complex isocyanate used extensively in polyurethane manufacturing. Knowing the key technical parameters will help you identify the right product and ensure it meets your specific industrial needs, whether for foams, coatings, or adhesives. This guide outlines essential PMDI specifications and how to evaluate them when you buy.

Key Specifications for PMDI: What Buyers Need to Know

When sourcing PMDI, several technical specifications dictate its suitability for various applications. A reputable manufacturer or supplier will readily provide these details:

  • Appearance: Typically described as a brown liquid. Consistency in color and clarity can indicate product purity and stability.
  • Purity / MDI Content: For many applications, particularly those requiring specific performance characteristics like high-resilience foam or demanding coating formulations, the percentage of active methylene diphenyl diisocyanate (MDI) is critical. Manufacturers may specify this as a percentage, e.g., 99.5% MDI.
  • Viscosity: Measured in centipoise (cP) or Pascal-seconds (Pa·s) at a specific temperature (e.g., 25°C), viscosity is vital for handling and processing. Lower viscosity generally implies easier flow and better pumpability, which is advantageous in automated manufacturing processes. Typical values might range from 150-250 mPa·s or higher for different grades.
  • NCO Content (%): This specification indicates the percentage of isocyanate (-NCO) groups by weight, which are the reactive sites in the molecule. A higher NCO content generally means higher reactivity and requires careful control during formulation. Typical NCO content for PMDI falls in the range of 30.5-32.0%.
  • Density: Expressed in g/mL or kg/L at a specific temperature (e.g., 25°C), density is important for volume-to-mass calculations and storage. A typical density for PMDI is around 1.220-1.250 g/cm³.
  • Acidity (HCl %): Low acidity is important as residual acid can catalyze unwanted side reactions or degrade the product over time. Specifications usually require it to be very low, e.g., ≤0.05%.
  • Hydrolyzable Chlorine (%): Similar to acidity, low levels of hydrolyzable chlorine are important for product stability and performance, particularly in sensitive applications.

Ensuring Quality When You Buy PMDI

When looking to buy PMDI, it's essential to partner with manufacturers who provide clear, detailed specifications and robust quality control. NINGBO INNO PHARMCHEM CO.,LTD. is a trusted supplier that prioritizes product integrity. We offer PMDI with guaranteed specifications, ensuring that our clients receive materials that meet the highest standards for their demanding applications. Our commitment extends to providing:

  • Detailed Technical Data Sheets (TDS): Comprehensive information on all relevant specifications.
  • Certifications: Assurance of quality through relevant industry certifications.
  • Sample Testing: We encourage customers to request samples to verify specifications and performance in their specific processes.

Understanding these specifications empowers you to make informed purchasing decisions. For your next requirement of PMDI, trust NINGBO INNO PHARMCHEM CO.,LTD. to provide quality and expertise. Contact us today to discuss your specific needs and receive a competitive quote.