Living anionic polymerization of 4‐diphenylphosphino styrene for ABC triblock copolymers

Abstract

Living anionic polymerization of 4-diphenylphosphino styrene (DPPS) achieved unprecedented poly(S-b-I-b-DPPS) ABC triblock copolymers with predictable molecular weights and narrow polydispersities. In situ Fourier transform infrared spectroscopy probed the anionic polymerization, monitoring vinyl disappearance during sequential monomer addition for kinetic analysis. Varying the concentration of reinforcing, polystyrenic external blocks enabled diverse compositions with tunable thermomechanical properties and tailored morphology. Dynamic mechanical analysis confirmed the presence of microphase separation in the triblock copolymers and revealed a broad temperature range (ca 100 o C) for a plateau region and onset of flow temperatures above 100 o C. Small-angle X-ray scattering and atomic force microscopy collectively revealed solid state morphologies of the triblock copolymers and probed phase separation at the nanoscale. Well-defined poly(S-b-I-b-DPPS) ABC triblock copolymers with tunable structure − property relationships now permit phosphorus-containing thermoplastic elastomers for emerging applications.

Phosphonium-Based Polyzwitterions: Influence of Ionic Structure and Association on Mechanical Properties

“…Previous work in our research laboratories explored triarylphosphine-containing polymers using the commercially available monomer, 4-(diphenylphosphino)­styrene (DPPS). − The polymers exhibited greater air stability due to the decreased oxygen sensitivity of arylphosphines in comparison to alkylphosphines . Thus, these polyphosphines served as stable precursors for the subsequent generation of phosphonium-based polyelectrolytes and ionomers upon postpolymerization alkylation.…”

Scandium-catalyzed stereoselective block and alternating copolymerization of diphenylphosphinostyrenes and isoprene

“…The living anionic copolymerization of StPPh 2 with styrene and isoprene was reported to afford block polymers with atactic polystyrene and 1,4-polyisoprene blocks. 42,43 The polymerization of p-StPPh 2 and its copolymerization with isoprene by TiCl 4 /aluminumisobutyl gave only low molecular weight oily products, while the obtained copolymers exhibited a maximum incorporation of p-StPPh 2 of only 2 mol%. 44 Recently, the polymerization of p,o-StPPh 2 using a fluorenyl-carbene scandium 45 or phosphine-sulfonate palladium 46 catalyst was not successful; however, the copolymerization of p-StPPh 2 with ethylene has been achieved using a fluorenyl-carbene scandium catalyst to afford alternating copolymers with high molecular weights.…”

ABC Supramolecular Triblock Copolymer by ROMP and ATRP

“…Most studies for the formation of nanoscale features from triblock copolymers are based on covalent systems with functionality and application preprogrammed in the polymer backbone − or side-chains − by design. The only example of a triblock BCP responsive to two orthogonal stimuli (temperature and gas) utilizes a single supramolecular moiety .…”