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Levi, Adam E.

Publications and source records attributed to Levi, Adam E..

Miktoarm Star Polymers: Synthesis and Applications

Polymers with precisely controlled structure and function are in high demand across a diverse array of applications spanning the life sciences and nanotechnology. One prototypical example is a class of branched block copolymers known as miktoarm stars (μ-stars), which contain two or more arm compositions connected at a common junction. Miktoarm stars have attracted considerable attention since their physical properties can be different from conventional linear block copolymers. This perspective highlights the latest developments and historical context in the field of miktoarm star polymers, including design strategies, synthetic techniques, and advanced characterization tools used to avoid common preparation pitfalls and tailor properties for emerging applications. Furthermore, our contemporary perspective on μ-star polymers is a resource for inspiring future research into this exciting class of materials at the intersection of chemistry, physics, and advanced technology.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Asymmetric Miktoarm Star Polymers as Polyester Thermoplastic Elastomers

A library of polyester-based A(BA') n asymmetric miktoarm star polymers was synthesized with A, A' = poly(l-lactide) (PLLA) as the semicrystalline hard blocks and B = poly(4-methylcaprolactone) (PMCL) as the soft segment using a grafting-through platform known as μSTAR. The synthetic versatility of μSTAR enabled a systematic investigation of architectural design parameters, in particular the number of BA' arms (n), while holding the A, A', and B block lengths constant. The value of n has a pronounced impact on the mechanical properties of these high-molecular-weight miktoarm materials. Tensile toughness increases with n, an effect likely related to bridging, as the modulus drops because the hard-block volume fraction decreases. Furthermore, these insights expand our understanding of architecture effects in sustainable thermoplastic elastomers.

36 MATERIALS SCIENCE↗