For professionals in the chemical industry, understanding product specifications is fundamental to making informed purchasing decisions. Toluene Diisocyanate (TDI) is a versatile organic intermediate, critical for many industrial applications, especially in polyurethane manufacturing. Ensuring that the TDI you purchase meets specific technical requirements is essential for product quality and process efficiency. This guide, provided by NINGBO INNO PHARMCHEM CO.,LTD., a leading TDI manufacturer in China, aims to clarify the key specifications of TDI.

Key Specifications of Toluene Diisocyanate (TDI)

When you buy TDI, you will encounter several critical specifications that define its quality and suitability for your applications. Here are the most important ones:

  • Purity: This refers to the percentage of the desired TDI isomers in the product. High-purity TDI, typically 99.9%, is crucial for many advanced applications, particularly in producing high-performance polyurethane foams, elastomers, and coatings. Lower purity can indicate the presence of unwanted byproducts or residual solvents, which can negatively affect reaction kinetics and final product properties.
  • Isomeric Ratio (e.g., 80/20): TDI exists as several isomers, with 2,4-TDI and 2,6-TDI being the most commercially significant. They are commonly sold as mixtures, such as 80/20 (80% 2,4-TDI and 20% 2,6-TDI) or 65/35. The isomeric ratio significantly influences the reaction rate and the physical properties of the resulting polyurethane. For instance, the 80/20 blend is preferred for most flexible foam applications due to its balanced reactivity.
  • Color (APHA): The color of TDI is an important indicator of its purity and stability. Commercial TDI is typically colorless, though slight yellowing may occur. A low APHA color value (e.g., less than 15) signifies good quality. Significant discoloration can suggest oxidation or contamination, impacting the aesthetic quality of the final product, especially in light-colored foams or coatings.
  • Acidity (on HCl basis): This specification measures the amount of acidic impurities, often expressed in parts per million (ppm) calculated as hydrochloric acid (HCl). High acidity can catalyze unwanted side reactions, affecting the stability and processing of TDI. Manufacturers aim to keep acidity levels low, typically below 30 ppm.
  • Hydrolyzable Chlorine: This parameter indicates the presence of chlorine-containing impurities that can react with moisture. High levels of hydrolyzable chlorine can also affect the reactivity and stability of TDI, so it is typically specified in low ppm values.

Why Specifications Matter for Buyers

Understanding these specifications allows you to:

  • Ensure Product Consistency: Reliable suppliers will provide consistent product that matches the stated specifications, enabling predictable manufacturing processes.
  • Optimize Performance: Using TDI that precisely matches your formulation requirements leads to superior final product characteristics.
  • Avoid Processing Issues: Adhering to specifications helps prevent unexpected reactions or product defects.
  • Make Informed Purchase Decisions: Comparing specifications from different TDI suppliers helps you identify the best value and quality for your needs.

Partnering for Quality: NINGBO INNO PHARMCHEM CO.,LTD.

As a reputable TDI supplier in China, NINGBO INNO PHARMCHEM CO.,LTD. is committed to transparency and quality. We provide detailed specifications for our Toluene Diisocyanate products, ensuring our clients can confidently purchase the right materials. Our 80/20 TDI blend is manufactured with high purity and controlled acidity, making it an ideal choice for demanding applications. Contact us to obtain comprehensive product data and discuss how our quality TDI can benefit your operations.