Dual-compartment nanofibres: separation of two highly reactive components in close vicinity

Abstract

Dual-compartment nanofibres separating two highly reactive components in close vicinity are investigated. The study is intended as a non-classical approach for the control of reaction latency in colloidal systems. An epoxide resin and a hydrophobic polyamine which react readily at low temperatures are chosen as model compounds. Colloid electrospinning with PVA as the confining matrix is used for the immobilization of both in separate compartments. Uniform fibres are produced with a matrix/colloid weight ratio of 3/1. The internal fibre morphology was investigated via dual-colour stimulated emission depletion (STED) microscopy and TEM. The results show a statistical distribution of epoxy- and amine-containing compartments and indicate average particle–particle distances of <100 nm, which is supported by computations. The fibres are highly storage stable under ambient conditions and yet allow for efficient crosslinking and self-healing. The curing reaction can be initiated via thermal or mechanical stimuli, as demonstrated by electron microscopy and electrochemical testing of fibre containing coatings. The reactivity and latency for reaction is furthermore proven by calorimetric and chromatographic methods.