Guanidines

Guanidines (DPG, DOTG) are slow-acting, basic secondary accelerators. They are rarely used alone; they activate thiazoles and sulfenamides.

They have an additional role in silica-filled compounds: by binding to the silica surface they prevent adsorption of the accelerators and support the silane reaction. Because of the health classification of DPG, the search for alternatives continues.