Hierarchical self?assembly of tannic acid/diethylenetriamine on polypropylene for high?performance separator
In situ reaction of ethyl cyanoacrylate on the surface of millimeter?scale calcium alginate capsules (Ca?SA caps) is performed based on interfacial polymerization mechanism. This coating method is universally applicable on surface modification of the hydrogel capsules, which remarkably enhances barrier property of the hydrogel capsules through rapid and mild reactions. Moreover, the biocompatible poly(ethyl cyanoacrylate) layer is eco?friendly.AbstractA rapid and mild coating strategy was applied on the millimeter scale calcium alginate capsules (Ca?SA caps) by in situ interfacial polymerization of ethyl cyanoacrylate (ECA). The generated poly(ethyl cyanoacrylate) (PECA) coating was initiated by trace water in the surface of the Ca?SA caps. The effects of ECA content, reaction time, and type of aromatic solvent on the morphology and control?release property of the resulting PECA?coated Ca?SA caps (Ca?SA caps@PECA) were investigated. The results demonstrated a white PECA layer successfully coated on the surface of Ca?SA caps. Notably, the Ca?SA caps@PECA remained consistently pleasing spherical shape as prepared in methylbenzene and ethylbenzene. When the ECA was 6?mL, the thickness of PECA layer of the Ca?SA caps@PECA was 43.52??m. Compared with the Ca?SA caps, the weight retention ratio of water in the Ca?SA caps@PECA increased by 254.61%, indicating the effective delay of water diffusion from core of the Ca?SA caps@PECA. Moreover, the PECA coating improved the stability of the Ca?SA caps@PECA, which achieved release?controlling of dye at different pH. This method provides solution for surface modification of fragile hydrogel capsules to effectively control the releasing of liquid core, which is highly valuable in the field of food, cosmetic, and medical delivery.