Here, we report the fabrication of montmorillonite (MMT) to incorporate an antifouling capability using 2‐chloro‐3′, 4′‐dihydroxyacetophenone (CCDP), and 1,3‐propanesultone quaternized poly(dimethyl amino)ethyl methacrylate [(C/S)‐q‐PDMA]. The dispersibility of MMT was improved through an ion exchange reaction between MMT and (C/S)‐q‐PDMA. The developed MMT with (C/S)‐q‐PDMA, consisting of catechol for adhesive properties, and this combination [(C/S)‐q‐PDMA] worked as a zwitterionic surfactants to enhance chain mobility in an aqueous medium. The d‐space interval is easy to enlarge and exfoliated the clay layers between MMT and different ratios of [(C/S)‐q‐PDMA] (1, 5, and 10 wt%). The degradation temperature of modified MMT composites is higher than that of the pure polymer without clay. The remaining CCDP moiety of MMT [(C/S)‐q‐PDMA] allowed easy access to surface coatings, which have been confirmed in terms of contact angle, XPS measurements, and antifouling effects through HeLa cell detachment. Finally, the beneficial influence of a coated polypropylene (PP) surface on the oxygen transmission rate and water vapor transmission suggest an emerging future for (C/S)‐q‐PDMA with an MMT hybrid coating composite. POLYM. ENG. SCI., 55:2111–2117, 2015. © 2014 Society of Plastics Engineers