Materials with good mechanical properties and minimal thickness are highly desirable for electromagnetic interference (EMI) shielding applications. In this work, we demonstrate a unique doctor blade approach to the sequential layering of polymeric thin-film composites to obtain a sandwiched film with approx. 53 µm thickness. Functional nanohybrid filler, such as ferrite decorated-reduced graphene oxide was synthesized using a solvothermal approach and composited with polyvinylidene difluoride. Carbon nanotubes were composited with polycarbonate and a mutually compatible polymer (polymethyl methacrylate) was chosen as the sandwich layer to interfacially lock polyvinylidene difluoride and polycarbonate composite layers. The dynamic mechanical analysis showed a significant improvement in the storage modulus of the sandwiched structure compared to individual layers. Moreover, the mechanical properties of films with polymethyl methacrylate as a sandwich layer were found to be better than that of without polymethyl methacrylate. A typical stack of 9 such films (~ 480 μm) gave a high EMI shield efficiency of -26.3 dB at 26.5 GHz frequency. This unique arrangement shields electromagnetic radiations mostly by absorption mechanism.

Broadband microwave absorption using thin-film sandwiched structure of compatible polymer composites

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.