Terpolymers from Borane-Initiated Copolymerization of Triphenyl Arsonium and Sulfoxonium Ylides: An Unexpected Light Emission

The first synthesis of well-defined poly[(phenylmethylene-co-methylpropenylene)-b-methylene, [(C1-co-C3)-b-C1], terpolymers was achieved by one-pot borane-initiated random copolymerization of ω-methylallyl (C3 units, chain is growing by three carbon atoms at a time) and benzyltriphenylarsonium (C1 units, chain is growing by one carbon atom at a time) ylides, followed by polymerization of sulfoxonium methylide (C1 units). Other substituted arsonium ylides, such as prenyltriphenyl, propyltriphenyl and (4-fluorobenzyl)triphenyl can also be used instead of benzyltriphenylarsonium. The obtained terpolymers are well-defined, possess a predictable molecular weight and low polydispersity (Mn,NMR =1.83-9.68×103  g mol-1 , Đ=1.09-1.22). An unexpected light emission phenomenon was discovered in these non-conjugated terpolymers, as confirmed by fluorescence and NMR spectroscopy. This phenomenon can be explained by the isomerization of the double bonds of allylic monomeric units along the chain of the terpolymers (isomerization-induced light emission).

Well-defined triblock copolymers of polyethylene with polycaprolactone or polystyrene using a novel difunctional polyhomologation initiator

α,ω-Dihydroxy polyethylene, valuable precursor for the synthesis of polyethylene-based terpolymers with polar blocks, was synthesized by polyhomologation of dimethylsulfoxonium methylide with 9-thexyl-9-BBN, a novel difunctional initiator with two active and one blocked sites.

C1 polymerization: a unique tool towards polyethylene-based complex macromolecular architectures

The recent developments in organoborane initiated C1 polymerization of ylides open unique horizons towards perfectly linear polymethylenes (equivalent to PE) and PE-based complex structures. This review summarizes research on conventional and newly discovered initiators/ylides, as well as initial efforts on C3 polymerization.

Allyl borates: a novel class of polyhomologation initiators

Allyl borates, a new class of monofunctional polyhomologation initiators, are reported. Upon increasing the ratio [ylide]/[B] the PM molecular weight increases correspondingly. The initiation mechanism was elucidated by¹H and¹¹B NMR.

Crystallization-driven one-dimensional self-assembly of polyethylene-b-poly(tert-butylacrylate) diblock copolymers in DMF: effects of crystallization temperature and the corona-forming block

Crystallization-driven self-assembly of polyethylene-b-poly(tert-butylacrylate) (PE-b-PtBA) block copolymers (BCPs) in N,N-dimethyl formamide (DMF) was studied. It is found that all three PE-b-PtBA BCPs used in this work can self-assemble into one-dimensional crystalline cylindrical micelles. When the BCP solution is cooled to crystallization temperature (Tc) from 130 °C, the seed micelles may be produced via two competitive processes in the initial period: stepwise micellization/crystallization and simultaneous crystallization/micellization. Subsequently, the seed micelles can undergo growth driven by the epitaxial crystallization of the unimers. The lengths of both the seed micelles and the grown micelles are longer for the BCP with a longer PtBA block at a higher Tc. Quasi-living growth of the PE-b-PtBA crystalline cylindrical micelles is achieved at a higher Tc. A longer PtBA block evidently retards the attachment of unimers to the crystalline micelles, leading to a slower growth rate.

Fabrication of honeycomb films from highly functional dendritic structures: electrostatic force driven immobilization of biomolecules

Herein we report the preparation of honeycomb porous films for selective immobilization of biomolecules via the breath figure technique, a water-assisted micropatterning method.