The effect of processing parameters on the formation of epoxy/UF resin microcapsules

Epoxy E-51/UF resin microcapsules were prepared by traditional two-stepped in situ polymerization method and processing parameters affecting the final microcapsules’ shape and size were carefully studied in the aim to obtain microcapsule with ideally spherical shape and uniform size. It’s found the polycarboxylate surfactant of SMA (styrene...

Preparation of mono-sized epoxy/MF microcapsulesin the appearance of polyvinyl alcohol as co-emulsifier

For epoxy microcapsules embedded in concrete as mechanic-triggered self-healing adhesive, globular shape with uniform size is the basic requirement to ensure the solid shell broken and the liquid core released at a designed stress. In this paper, monodispersed melamine–formaldehyde (MF) resin-walled epoxy E-51 microcapsules were successfully...

Interaction between microcapsules and cementitious matrix after cracking in a self-healing system

A new type of self-healing cementitious composites by using organic microcapsules is designed in Guangdong Key Laboratory of Durability for Coastal Civil Engineering, Shenzhen University. For the organic microcapsules, the shell material is urea formoldehyde (UF), and the core healing agent is Epoxy. The effect of organic microcapsules on...

Design of microcapsule system used for self-healing cementitious material

For a microcapsule based self-healing system in the cementitious material, a fundamental issue is to find and facilitate a suitable microcapsule system, concerning either the material selection or design and manufacture process. In this study, urea formaldehyde resin is used for the shell of microcapsule, and bisphenol – an epoxy resin E-51...

The smart releasing behavior of a microcapsule based on chemical self-healing system caused by chemical trigger activation

A novel chemical self-healing system based on microcapsule technology for cementitious composites is established in Guangdong Key Laboratory of Durability for Coastal Civil Engineering, Shenzhen University. The key issue of this system is how to release the healing material and how to activate the healing mechanism. In this paper, the study is...

Evaluation of a microcapsule based self-healing system for cementitious materials

An international cooperation research project has been financially supported by China Nature Science Foundation, which consists of three relatively independent, but strategically integrated research sub-programs, aiming at the formation of a selfhealing system based on the microcapsule principle for the cementitious composites. In this paper, a...

Preparation and characterization of poly (urea-formaldehyde) walled dicyclopentadiene microcapsules

Poly (urea-formaldehyde) (PUF) shelled dicyclopentadiene (DCPD) microcapsules were prepared by in-situ polymerization technology for self-healing concrete applications. It’s found, during the process, sodium dodecyl benzene sulfonate (SDBS) behaves better in emulsification of DCPD than other surfactant of sodium lauryl sulfate (SLS) and styrene...

A study on the steel corrosion protection of a microcapsule based self-healing cementitious system by means of electrochemical impedance spectroscopy

Based on microcapsule technology, a new type of self-healing system for cementitious composites is established. The performance of the system was characterized by means of electrochemical impedance spectroscopy of steel bars immersed in a simulated concrete environment. The results demonstrate strong inhibition of chloride-induced corrosion when...

Self-encapsulation of epoxy resin by a controlled interface curing process in epoxy/water emulsion

The microcapsules of epoxy E-51 resin encapsulated by cured itself were prepared by interfacial curing reaction, in which ethylenediamine (EDA) was employed as curing agent and sulfonated copolymer of styrene and maleic anhydride (SMA) as emulsifying agent. It’s found the morphology of microcapsules strongly depend on reaction time and EDA...