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1. Nanoscale Q -Resolved Phonon Dynamics in Block Copolymers

   https://doi.org/10.1021/acsanm.8b01087  

   Bolmatov, Dima; Zhang, Qi; Soloviov, Dmytro; Li, Yuk Mun; Werner, Jörg G.; Suvorov, Alexey; Cai, Yong Q.; Wiesner, Ulrich; Zhernenkov, Mikhail; Katsaras, John (August 2018, ACS Applied Nano Materials)
2. Threading-the-Needle: Compatibilization of HDPE/ i PP blends with butadiene-derived polyolefin block copolymers

   https://doi.org/10.1073/pnas.2301352120  

   Shen, Liyang; Gorbea, Gabriela Diaz; Danielson, Evan; Cui, Shuquan; Ellison, Christopher J.; Bates, Frank S. (August 2023, Proceedings of the National Academy of Sciences)

   Management of the plastic industry is a momentous challenge, one that pits enormous societal benefits against an accumulating reservoir of nearly indestructible waste. A promising strategy for recycling polyethylene (PE) and isotactic polypropylene ( i PP), constituting roughly half the plastic produced annually worldwide, is melt blending for reformulation into useful products. Unfortunately, such blends are generally brittle and useless due to phase separation and mechanically weak domain interfaces. Recent studies have shown that addition of small amounts of semicrystalline PE- i PP block copolymers (ca. 1 wt%) to mixtures of these polyolefins results in ductility comparable to the pure materials. However, current methods for producing such additives rely on expensive reagents, prohibitively impacting the cost of recycling these inexpensive commodity plastics. Here, we describe an alternative strategy that exploits anionic polymerization of butadiene into block copolymers, with subsequent catalytic hydrogenation, yielding E and X blocks that are individually melt miscible with PE and i PP, where E and X are poly(ethylene- ran -ethylethylene) random copolymers with 6 wt% and 90 wt% ethylethylene repeat units, respectively. Cooling melt blended mixtures of PE and i PP containing 1 wt% of the triblock copolymer EXE of appropriate molecular weight, results in mechanical properties competitive with the component plastics. Blend toughness is obtained through interfacial topological entanglements of the amorphous X polymer and semicrystalline i PP, along with anchoring of the E blocks through cocrystallization with the PE homopolymer. Significantly, EXE can be inexpensively produced using currently practiced industrial scale polymerization methods, offering a practical approach to recycling the world’s top two plastics. 

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3. Self-Assembly of Poly(styrene- block -acrylated epoxidized soybean oil) Star-Brush-Like Block Copolymers

   https://doi.org/10.1021/acs.macromol.0c00441  

   Lin, Fang-Yi; Hohmann, Austin D.; Hernández, Nacú; Shen, Liyang; Dietrich, Hannah; Cochran, Eric W. (September 2020, Macromolecules)

   null (Ed.)
4. Cell Engineering with Functional Poly(oxanorbornene) Block Copolymers

   https://doi.org/10.1002/anie.202005148  

   Church, Derek C.; Pokorski, Jonathan K. (May 2020, Angewandte Chemie International Edition)

   Abstract Cell‐based therapies are gaining prominence in treating a wide variety of diseases and using synthetic polymers to manipulate these cells provides an opportunity to impart function that could not be achieved using solely genetic means. Herein, we describe the utility of functional block copolymers synthesized by ring‐opening metathesis polymerization (ROMP) that can insert directly into the cell membrane via the incorporation of long alkyl chains into a short polymer block leading to non‐covalent, hydrophobic interactions with the lipid bilayer. Furthermore, we demonstrate that these polymers can be imbued with advanced functionalities. A photosensitizer was incorporated into these polymers to enable spatially controlled cell death by the localized generation of¹O₂at the cell surface in response to red‐light irradiation. In a broader context, we believe our polymer insertion strategy could be used as a general methodology to impart functionality onto cell‐surfaces. 

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5. Random copolymerization of macromonomers as a versatile strategy to synthesize mixed‐graft block copolymers

   https://doi.org/10.1002/pol.20210407  

   Le, An N.; Liang, Ruiqi; Ji, Xiaoyu; Fu, Xiaowei; Zhong, Mingjiang (July 2021, Journal of Polymer Science)

   Abstract The random copolymerization of norbornene‐functionalized macromonomers was explored as a method of synthesizing mixed‐graft block copolymers (mGBCPs). The copolymerization kinetics of a model system of polystyrene (PS) and poly(lactic acid) (PLA) macromonomers was first analyzed, revealing a gradient composition of side chains along the mGBCP backbone. The phase separation behavior of mGBCPs with PS and PLA side chains of various backbone lengths and side chain molar ratios was investigated, and increasing the backbone length was found to stabilize the phase‐separated nanostructures. The graft architecture was also demonstrated to improve the processability of the mGBCP, compared to a linear counterpart. Investigations of mGBCPs comprised of polydimethylsiloxane and poly(ethylene oxide) side chains exemplified the diverse self‐assembled morphologies, including a Frank‐Kasper A15 phase, that can be obtained with mGBCPs synthesized by random copolymerization of macromonomers. Lastly, a ternary mGBCP was synthesized by the copolymerization of three macromonomers. 

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