Abstract: The invention relates to a fatty acid diamide-based rheology additive composition, which is pre-activated and pre-concentrated in fatty acid diamide, comprising: a) from 5% to 30% by weight of at least one fatty acid diamide based on 12 hydroxystearic acid and on a linear, in particular C5, C6 or C7, aliphatic diamine, b) from 70% to 95% by weight of at least one monofunctional (meth)acrylic reactive diluent comprising a cycloaliphatic group or several cycloaliphatic groups, the % being expressed relative to a)+b). It also relates to a process for preparing the composition and to the use thereof as a rheology additive in reactive binder compositions such as coating, moulding, composite material, anchor bolt or sealant compositions or photocrosslinkable compositions for stereolithography or for 3D printing of objects by inkjet.

Abstract: The present invention relates to a rheology additive, according to which A) said additive consists of: a) at least one symmetrical fatty diamide of formula (I): (AGH)—CONH—(PMDA)-NHCO-(AGH) (I) with: (AGH): hydroxylated fatty acid residue R1CO2H, without —CO2H group, with R1 of C18 to C20 comprising a hydroxyl group, —NHCO— or —CONH—: amide group, —(PMDA): residue without amine groups of 1,5-pentamethylenediamine; or alternatively according to which: B) said additive comprises: a) at least one symmetrical fatty diamide as defined above according to formula (I) and, in addition, b) at least one other symmetrical fatty diamide of formula (II): (AGH)—CONH—(R)—NHCO-(AGH) (II) with (AGH), —NHCO— and —CONH— having the same definition as that above in said formula (I), and (R) being the residue without amine groups of a diamine, other than (PMDA), chosen from a cycloaliphatic, aliphatic or aromatic diamine.