3glycidyloxypropyltrimethoxysilane

3-Glycidyloxypropyltrimethoxysilane, commonly abbreviated GPTMS, is an organosilane coupling agent used to introduce epoxy functionality onto inorganic surfaces and within organic polymers. It features a glycidyl (epoxy) group connected through a propyl linker to a silicon atom bearing three methoxy groups, enabling compatibility with both siliceous substrates and epoxy resins.

In the presence of moisture, GPTMS undergoes hydrolysis of the silane to form silanols, which can condense to form siloxane networks. The glycidyl epoxy group remains reactive, allowing post-grafting crosslinking with amines, acids, or phenols in curing epoxy systems. This dual reactivity makes GPTMS useful for coupling glass, silica, and metal oxides to polymers and for forming crosslinked coatings and composites.

Common applications include surface modification of glass and silica particles, formulation of epoxy-based coatings and adhesives, and as a primer or compatibilizer in sol-gel processes. It is used to improve adhesion, chemical resistance, and mechanical properties of coatings on diverse substrates and to enhance dispersion of inorganic fillers in epoxy or other resin matrices.

Safety considerations include handling GPTMS with care, as it can be an irritant to skin, eyes, and respiratory tract. Hydrolysis can release methanol, so appropriate ventilation, and protective equipment are recommended. Storage should be in a cool, dry place away from moisture to minimize premature hydrolysis.