COMPOSITION CROSSLINKABLE BY REAL MICHAEL ADDITION (RMA) REACTION

摘要

The present invention relates to a crosslinkable composition crosslinkable by Real Michael Addition (RMA) reaction comprising a component with at least 2 activated unsaturated groups (hereafter referred to as the RMA acceptor groups) and a component with at least 2 acidic protons C-H in activated methylene or methine groups (hereafter referred to as the RMA donor groups) which components can react to form a crosslinked network. The composition comprises: f. Component(s) A having at least 2 acidic C-H donor groups in activated methylene or methine and having a pKa(A) between 10.5 and 14; g. Component(s) B having at least 2 activated unsaturated acceptor groups, wherein a molar ratio R of acceptor groups to donor groups is between 3:1 to 1:6 and which component(s) B react with component(s) A by Real Michael Addition (RMA) to form a crosslinked network; h. basic component(s) C being a salt of a basic anion X- from an acidic X-H group containing compound wherein X is N, P, O, S or C: iv. in an amount xc between 0.001 and 1 meq/(gr of components A, B, C, D), v. anion X- being a Michael Addition donor reactable with component B and vi. anion X- is characterized by a pKa(C) of the corresponding acid X-H of more than two units lower than the pKa(A) of the majority component A and being lower than 10.5; i. optional component(s) D comprising one or more acidic X'-H groups wherein X' is N, P, O, S or C: v. X' being a same or different group as group X in component C, vi. the X'- anion being a Michael Addition donor reactable with component B, vii. the pKa(D) of the X'-H group in component D being more than two units lower than pKa(A) of the majority component A and being lower than 10.5, viii. the equivalent ratio Rd/c of acidic X'-H groups in component D over basic anion X- in component C is between 1% and 5000%.