Patent ID: 8759443
Filing Date: 2014-06-24
Classification: C07D,C08G,C08K,C08L

Abstract:
1. A curable composition comprising: (a) at least one thermosetting benzoxazine resin and (b) at least one thermoplastic toughening additive soluble in the at least one thermosetting benzoxazine resin prior to curing and reactive with the at least one thermosetting benzoxazine resin in the curing process, wherein the at least one thermoplastic toughening additive is a benzoxazine macromonomer or an isocyanate-terminated prepolymer, wherein prior to curing, the curable composition is homogeneous but when the curable composition is cured to form a cured product, phase separation is observed with the thermoplastic toughening additive distributed in the cured product in the form of discrete domains therein, and wherein at least 60% of the discrete domains have a maximum length in any direction of space in the range of 25 nm to 200 nm as determined by transmission electron microscopy (TEM).