Methyl Diphenyl Diisocyanate (MDI)

Introduction
Suprasec 2412 is a prepolymerised diphenyl methane diisocyante (MDI), containing some higher functionality isocyanates.

Typical Properties

AppearanceBrown colored liquid
Density (g/cm3 at 25°C)1.19
Viscosity (cps at 25°C)160
Flash Point (°C)(a)192
Fire Point (°C)(a)220
Isocyanate (NCO) value (%)(b)26.1

(a) Cleveland Cup, ASTM method D92
(b) Corrected for hydrolysable chlorine

Applications
Suprasec 2412 has been developed for the production of a variety of polyurethane materials, including flexible foam molding.

Storage
Containers of Suprasec 2412 should be kept properly closed and stored indoors in a well-ventilated area under normal factory conditions. Storage at temperatures ranging from 15 – 35°C provides a convenient viscosity for handling. Storage at low temperature(below 10°C) is not recommended because it may lead to some crystallization; This material must therefore be protected from frost. If under abnormal storage conditions some crystallization does occur, the material should be melted according to the procedures given in the publication PU 181- 15E. Storage at temperatures above 50°C is not recommended, since this can lead to the formation of insoluble solids and also the viscosity build-up increases on extended storage. Under the recommended storage conditions and if protected from humidity and contaminants, i.e. in properly sealed drums, cans, etc., Suprasec 2412 has a provisional storage life of 3 months at the customer. Detailed information on how to obtain optimum bulk storage conditions is available in the ISOPA document Guidelines for Safe Loading/unloading, Transportation & Storage on TDI and MDI. Reaction with atmospheric moisture is prevented by storing Suprasec 2412 in carefully sealed containers under a dry air atmosphere. During handling, the product must be protected from water ingress and from atmospheric moisture. Containers should be re-sealed immediately after each sampling. The reaction of isocyanates with water leads to the formation of insoluble ureas and carbon dioxide gas, which can lead to pressure build-up in closed containers. Containers used for Suprasec 2412 must therefore be absolutely dry.

Handling Precautions
Suprasec 2412, i.e., MDI, and the decontamination procedures recommended to be used in case of spillage, are described fully in the publication PU 193-1 E; MDI-based compositions: Hazards and safe handling procedure. Should it prove necessary to melt Suprasec 2412 procedures are given in the publication PU 181-15E Recommended melting procedures for MDI-based isocyanates.

Health and Safety Advice
The appropriate health and safety advice can be found in the safety data sheet for Suprasec 2412 available on request. The applicable Safety Data Sheet should be reviewed by customer before handling the product. All users of Suprasec 2412 are advised to read the publication PU 193-1E; MDI-based compositions: Hazards and safe-handling procedures.