Colorimetric sensors of poly(acrylic acid) and poly(4-styrenesulfonic acid) using polydiacetylene/zinc(II)/zinc oxide nanocomposites

Abstract

Color-responsive polydiacetylenes (PDAs) have been utilized for detecting different types of stimuli. However, the utilization of PDA-based materials for sensing polymers is rarely applied. This work introduces a facile approach to develop the PDA-based nanocomposites for colorimetric detection of acidic polymers in aqueous solutions. The sensors can be fabricated by a simple mixing of PDA/Zn2+/ZnO nanocomposites and cetyltrimethylammonium bromide (CTAB). The PDA/Zn2+/ZnO-CTAB sensors exhibit colorimetric responses to poly(acrylic acid) (PAA) and poly(4-styrenesulfonic acid). The sensors change color at different PAA concentrations, governed by the ratios of CTAB within the nanocomposites. The ability to control the sensitivity allows applications of this system for semi-quantitative analysis. Furthermore, the sensors can differentiate the molecular weight and structure of the acidic polymers. Our approach is simple and low-cost, desirable for large-scale production. This study offers a new development path of the PDA-based materials, expanding their utilization in polymer sensing technologies. Graphical abstract: [Figure not available: see fulltext.].