Transparent Intrinsic Barrier Polymer via Dynamic Pressure Engineering

Polymers with desirable barrier performances are urgentlydemandedfor various applications, especially in dealing with COVID19. Currentart mostly focuses on copolymerization, crystallization, melt blending,and surface modification, ultimately leading to compromised transparency,mechanical performances, and potential medical safety. In this work,we report a dynamic pressure driven approach for the first time cantranslate conventional nonbarrier polyethylene terephthalate (PET)into intrinsic barrier (ib-PET) material while maintaining its outstandingtransparence by a single step. The oxygen permeability and water vaportransmission rate are 88% and 43% lower than those for conventionaltechnique-processed nonbarrier PET, respectively, resulting from slowerchain dynamics and reduction in the free volume. This work can constructa prospective avenue toward rational design for pristine materialswith outstanding barrier properties and provide in-depth insight intothe perception of dynamic pressure engineering, as well as providea novel concept for tailoring and design of advanced polymers fromthe energy point of view.