Optimizing interfacial compatibility is one of the core issues for constructing high-performance green poly­(lactic acid) (PLA) blends. Herein, we prepared a poly­(epichlorohydrin)-b-poly­(d-lactic acid) (PECH-b-PDLA) diblock copolymer as an efficient compatibilizer for poly­(l-lactic acid)/poly­(epichlorohydrin) (PLLA/CHR) blends. The PECH-b-PDLA enabled the blends to form unique interlocks among the chains through combining the strong dipolar interaction and PLLA/PDLA stereocomplexation (SC). This strategy endows the PLLA/CHR blend with a unique “co-continuous” structure composed of CHR particles as the core and a bilayer shell formed by the PECH entanglement layer with strong dipolar interaction and a rigid SC thin layer. Physical properties of the blends were remarkably improved by a co-continuous structure with enhanced interfacial adhesion between phases. The optimum formulation showed unprecedented balanced mechanical properties: a nonbroken sample with an impact strength of 106.7 kJ/m2 and a high elongation at break of up to 467.2%; both were about 40 times those of pure PLLA. The interlocking mechanism through strong dipolar interaction and SC provides a broadly applicable and facile strategy to achieve PLA materials with superior properties for expanded industrial application.

The development of materials with intrinsic antimicrobial activities has attracted great interest. In this contribution, cyclic olefin polymers (COPs) with excellent mechanical strength and high glass-transition temperature were prepared via ring-opening metathesis polymerization of both a bulky cyclic monomer and a cyclic monomer bearing ionic groups. The ionic COP membranes we obtained showed high antibacterial properties against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus); especially, the sterilization rate of H-Qa on both bacteria was higher than 99%, and it still showed a high bacteriostatic rate after repeated supplementation of new bacteria for 7 days. In addition, high light transmittance (80–90% in vis), excellent thermal stability (T d,95 > 210 °C), and low water vapor/oxygen transmittance also make the COPs promising as a bacteriostatic material with promising application potential in packaging, medical, and other fields.