Simulation-Aided Design of Tubular Polymeric Capsules for Self-Healing Concrete.

Polymeric capsules can have an advantage over glass capsules used up to now as proof-of-concept carriers in self-healing concrete. They allow easier processing and afford the possibility to fine tune their mechanical properties. Out of the multiple requirements for capsules used in this context, the capability of rupturing when crossed by a crack in concrete of a typical size is one of the most relevant, as without it no healing agent is released into the crack.

Single step coupling for multi-responsive water-based chitin/chitosan magnetic nanoparticles.

Coupling of chitin whisker (CTWK) or water-soluble chitosan (WSCS) with magnetic nanoparticles (MAG) via a covalent linkage by using a silane coupling agent in an aqueous system is proposed. The use of the silane coupling agent glycidoxypropyltrimethoxy, having a trimethoxy silane as well as an epoxide functionality, allows one step coupling between CTWK or WSCS and MAG. The MAG derivatives obtained are well dispersed and their colloidal aqueous solutions can be stabilized for days.