Colorimetric detection of poly(methyl methacrylate) using polydiacetylene/zinc(II)/zinc oxide nanocomposites

This study introduces a facile approach for fabricating colorimetric sensors that differentiate concentration and molecular weight of poly(methyl methacrylate) (PMMA). A cationic surfactant, cetyltrimethylammonium bromide (CTAB), is incorporated into the structure of polydiacetylene(PDA)/Zn²⁺/ZnO nanocomposites via a simple mixing process. The interaction between PMMA carbonyl group and CTAB headgroup is the key mechanism inducing color transition of the nanocomposites. The sensitivity can be tuned by adjusting experimental parameters including CTAB concentration, photopolymerization time, and PDA alkyl chain length. Solid-state sensors are fabricated by embedding into filter papers. Our finding extends the utilization of PDA-based materials in polymer sensing applications.