| 摘要 |
The invention relates to an acrylic oligomer, having a number-average acrylate functionality fo > 2, of branched structure resulting from the polyaddition reaction of at least one amine A) having a functionality fA of N-H groups of at least 2, to at least one multifunctional acrylate B) having a functionality fB of acrylate groups of at least 2 with an average functionality per mole of all of the components A) + B) of greater than 2 and with said oligomer comprising, in its repeat unit structure, at least one aminoacrylate group -O2C-CH2-CH2-N= resulting from said polyaddition and with a content of nitrogen resulting from said amine A) of greater than or equal to 0.35 mEq/g and an initial ratio r = acrylate / N-H of between rinf and 1.1 rsup with rinf = 0.90*(fA-1 )*(fB -1 ) and rsup = 2*fA + 2*fB - 6 and the average number nav of said repeat units per oligomer nav = 1 / [(r*fA/fB) + 1 - fA]. The invention also relates to a specific preparation process and to the use of said oligomer in crosslinkable compositions, in particular as UV synergist in crosslinkable coatings, such as inks, varnishes, paints, adhesives, or gel coats or in moulding compositions or in compositions for 3D articles made by superposition of successive layers, and finally to the crosslinked product that results therefrom. |
