Composition for structural adhesive

A composition that can be used in a structural adhesive, said structural adhesive being formed from said composition and from a catalyst comprising a radical polymerization initiator of peroxide type, said composition comprising:

• (a) at least one methacrylate ester monomer,
• (b) a phosphate-ester-based adhesion promoter,
• (c) a cure accelerator comprising a tertiary amine of formula I:
• in which:
• the R3 group is a resonance electron-donating group comprising at least one aromatic group which is capable of forming, with the radical:
• and in combination with said radical polymerization initiator, a conjugated system exhibiting an absorption in the visible field of the electromagnetic spectrum, for generating coloration of said polymer or of said cement during the reaction for polymerization of said monomer,
• the R1 and R2 groups are respectively and independently:
• linear or branched C1 to C16, preferably C1 to C5, alkyl groups,
• C5 to C30, preferably C5 to C10, aryl or arylalkyl groups,
• C2 to C15, preferably C2 to C5, alkylidene groups.