A novel coil-first/grafting-from
approach was developed for the
synthesis of conjugated rod–coil block copolymers using RuPhos
Pd-catalyzed Suzuki–Miyaura catalyst-transfer polycondensation
(SCTP). First, aryl iodide end-functionalized polystyrene (PS) was
prepared as a macroinitiator for SCTP via atom transfer radical polymerization
(ATRP) followed by sequential end-group modifications, azidation,
and click reactions. Then, RuPhos Pd-catalyzed SCTP using the PS macroinitiator
was carried out in the presence of N-methyliminodiacetic
acid boronate-containing 3-hexylthiophene monomer (M1), and this afforded well-defined PS-block-poly(3-hexylthiophene)
with excellent control and high yield. The scope of this method was
successfully expanded to include poly(methyl acrylate)-, poly(methyl
methacrylate)-, and poly(ethylene oxide)-block-poly(3-hexylthiophene)
with controlled molecular weight and low dispersity. Further, the
combination of the conventional rod-first and newly developed coil-first
approaches facilitated the straightforward synthesis of a unique ABC-type
rod–coil–rod triblock copolymer that was limitedly accessible
by other methods. We believe that this efficient and readily accessible
synthetic platform would be highly useful for the preparation of novel
conjugated rod–coil block copolymers that can be applied in
optoelectronics, battery engineering, and chemical sensing.
Zinc-glutarate (ZnGA) is a promising catalyst that can form polymers from CO2 and epoxides, thereby contributing to the development of CO2 utilization technologies and future sustainability. One of the obstacles...
Palladium catalysts modified with iminopyridine ligands were employed for ethylene/CO and styrene/CO copolymerization and ethylene/styrene/CO terpolymerization. Our studies revealed that the steric and electronic effects of the catalysts play key, yet distinct roles in these polymerization reactions. The thermal properties of the polyketones were engineered by varying the styrene content in terpolymers derived from ethylene, styrene, and CO sources, with increased styrene ratios yielding reduced polyketone crystallinity.
Precise control of multiple structural parameters associated with vinyl polymers is important for producing materials with the desired properties and functions. While the development of living polymerization methods has provided a way to control the various structural parameters of vinyl polymers, the concomitant control of their sequence and regioregularity remains a challenging task. To overcome this challenge, herein, we report the living cationic ringopening polymerization of hetero Diels-Alder adducts. The scalable and modular synthesis of the cyclic monomers was achieved by a one-step protocol using readily available vinyl precursors. Subsequently, living polymerization of the cyclic monomers was examined, allowing the synthesis of vinyl polymers while controlling multiple factors, including molecular weight, dispersity, alternating sequence, head-to-head regioregularity, and end-group functionality. The living characteristics of the developed method were further demonstrated by block copolymerization. The synthesized vinyl polymers exhibited unique thermal properties and underwent fast photodegradation even under sunlight.
Precise control of multiple structural parameters associated with vinyl polymers is important for producing materials with the desired properties and functions. While the development of living polymerization methods has provided a way to control the various structural parameters of vinyl polymers, the concomitant control of their sequence and regioregularity remains a challenging task. To overcome this challenge, herein, we report the living cationic ringopening polymerization of hetero Diels-Alder adducts. The scalable and modular synthesis of the cyclic monomers was achieved by a one-step protocol using readily available vinyl precursors. Subsequently, living polymerization of the cyclic monomers was examined, allowing the synthesis of vinyl polymers while controlling multiple factors, including molecular weight, dispersity, alternating sequence, head-to-head regioregularity, and end-group functionality. The living characteristics of the developed method were further demonstrated by block copolymerization. The synthesized vinyl polymers exhibited unique thermal properties and underwent fast photodegradation even under sunlight.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.