Microfluidic Synthesis of Ca-Alginate Microcapsules for Self-Healing of Bituminous Binder

Abstract

This work aims to develop an original alginate micro-emulsion combining with droplets microfluidic method to produce multinuclear Ca-alginate microcapsules containing rejuvenator for the self-healing of bituminous binder. The sizes of the Ca-alginate microcapsules could be easily controlled by tuning flow rates of the continuous and dispersed phases. The addition of a surfactant Tween80 not only improved the stability of the emulsion, but it also effectively reduced the size of the microcapsules. Size predictive mathematical model of the microcapsules was proposed through the analysis of fluid force. Optical microscope and remote Fourier infrared test confirmed the multinuclear structure of Ca-alginate microcapsules. Thermogravimetric analysis showed that the microcapsules coated with nearly 40% rejuvenator and they remained intact during the preparation of bitumen specimen at 135 °C. Micro self-healing process of bituminous binder with multinuclear Ca-alginate microcapsules containing rejuvenator was monitored and showed enhanced self-healing performance. Tensile stress-recovery test revealed that the recovery rate increased by 32.08% (in the case of 5% microcapsules), which meant that the Ca-alginate microcapsules containing rejuvenator could effectively enhance the self-healing property of bituminous binder.

Morphology and Thermal Properties of Calcium Alginate/Reduced Graphene Oxide Composites

“…The FT-IR spectra of the CaAlg and CaAlg/rGO materials are shown in Figure 1. The main characteristic absorption peak positions and intensity of CaAlg and CaAlg/rGO were basically identical [20,21]. The broad and strong peaks at 3425 cm −1 can be ascribed to the stretching vibration absorption peak of –OH bond.…”

Recent Trends in Three-Dimensional Bioinks Based on Alginate for Biomedical Applications

“…It is worth noting that we are still a great distance from organ printing. Even though recent deposition and manufacturing systems permit us to develop structures similar to tissue in their composition, the progression of entirely functioning tissue is a much more significant step [ 154 , 155 , 156 , 157 , 158 , 159 , 160 , 161 , 162 , 163 , 164 , 165 , 166 , 167 , 168 , 169 , 170 , 171 , 172 , 173 , 174 , 175 , 176 , 177 ].…”

Preparation and Characterization of Ethylenediamine-Polyurea Microcapsule Epoxy Self-Healing Coating

“…In addition, these internally generated micro-cracks are difficult to restore from the outside using existing methods. To solve this problem, self-healing coatings have been studied as protective materials and exploited extensively in the past few years [1][2][3][4]. Self-healing coatings can respond quickly to environmental changes and repair material damage automatically.…”