4,4’-Methylene Bis (Phenyl Dimethyl Urea)



(OMICURE^TM U-52)

Omicure U-52 (4,4’-Methylene Bis (Phenyl Dimethyl Urea)) is an aromatic substituted urea. It is intended for use as a latent accelerator for the dicyandiamide cure of epoxy resins. The addition of Omicure U-52 to epoxy/dicy formulations produces shelf stable one part products which cure in shorter times and/or at lower temperatures. Of the CVC substituted ureas, methylene bis (phenyl dimethyl urea) provides the best combination or acceleration, long shelf life and maintenance of cured properties in dicy DGEBA.

                                         Typical Properties:

                                                          CAS Number                                                      10097-09-3

                                                          Formula                                                               C₁₉H₂₄N₄O₂

                                                          Formula Weight                                                  340.42

                                                          Appearance                                                        Off White Crystalline Powder

                                                          Odor                                                                     Ammoniacal

                                                          Specific Gravity                                                  > 1

                                                          Melting Point                                                       220 – 230^oC

                                                          Moisture Content                                                0.7% maximum

                                                          Particle Size (% through a 325 Mesh Screen) 80%

Suggested Use levels of Omicure U-52 in DGEBA/DICY are < 5 phr. At 5 phr curing can be accomplished in about one hour at 100^oC and in less than five minutes at temperatures > 150^oC. Room temperature shelf lives (doubling of viscosity) are longer than six months. Cure times and shelf lives are dependent on composition of the formulated product and your particular end application. Some factors which can affect shelf life are formulation ingredients and compounding parameters. Ingredients in which Omicure U-52 is insoluble at processing and storage temperatures will enhance overall storage stability. Omicure U-52 can be incorporated into your formulation concurrent with the dicy addition.