Ternary composites by an in situ hydrolytic polymerization process

RSC Adv. 2018 Apr 18;8(26):14713-14721. doi: 10.1039/c8ra02402b. eCollection 2018 Apr 17.

Abstract

Polyamide 6/modified silica composite materials have been prepared by a coupled polymerization procedure. For this purpose, the three-component-system we presented in a previous publication, consisting of ε-aminocaproic acid (ε-ACA), ε-caprolactam (ε-CL), and 1,1',1'',1'''-silanetetrayltetrakis-(azepan-2-one) (Si(ε-CL)4), has been combined with other silicon monomers with one or two methyl groups (MeSi(ε-CL)3 and Me2Si(ε-CL)2). The simultaneous polymerization of ε-CL and silicon monomers leads to the in situ formation of silica/polysiloxane particles and the surrounding polyamide 6 matrix in one step. Moreover, 3-aminopropyltriethoxysilane has been added to the three-component-system to achieve covalent bonding between organic and inorganic phases and to inhibit agglomeration of the silica particles. Chemical structures and morphologies of the composites have been investigated by solid-state NMR and FTIR spectroscopy as well as electron microscopy and SEC measurements. Structural effects on thermal properties have been studied by DSC and TGA measurements.