What will happen when thermoresponsive poly(-isopropylacrylamide) is tethered on poly(ionic liquid)s?

The thermoresponsive ionic liquid diblock copolymer of poly[1-(4-vinylbenzyl)-3-methylimidazolium tetrafluoroborate]--poly(-isopropylacrylamide) (P[VBMI][BF]--PNIPAM) containing a hydrophilic poly(ionic liquid) block of P[VBMI][BF] is prepared by sequential reversible addition-fragmentation chain transfer (RAFT) polymerization. This P[VBMI][BF]--PNIPAM exhibits an abnormal thermoresponsive phase transition at a temperature above the phase transition temperature (PTT) of the PNIPAM block. For P[VBMI][BF]--PNIPAM including a short P[VBMI][BF] block, its aqueous solution becomes turbid at a temperature above the PTT of the thermoresponsive PNIPAM block, whereas for P[VBMI][BF]--PNIPAM containing a relatively long P[VBMI][BF] block even in the case of a relatively long PNIPAM block, the aqueous solution remains transparent at a temperature far above the PTT of the PNIPAM block, although a soluble-to-insoluble phase transition of the PINIPAM block is confirmed by dynamic light scattering (DLS) analysis and variable temperature H NMR analysis.

Redox-Responsive Multicompartment Vesicles of Ferrocene-Containing Triblock Terpolymer Exhibiting On-Off Switchable Pores.

Multicompartment vesicles of ferrocene-containing triblock terpolymer containing on-off switchable pores in the vesicular membrane are prepared by seeded RAFT polymerization. In these multicompartment vesicles, the incompatible solvophobic poly(4-vinylbenzyl ferrocenecarboxylate) (PVFC) and poly(benzyl methacrylate) (PBzMA) blocks form the porous phase-segregated membrane and the solvophilic poly[2-(dimethylamino) ethyl methacrylate] block locates at the inner and outer sides of the membrane. These porous multicompartment vesicles are redox-responsive and the membrane pores can be on-off switched through redox triggering.