Highly-branched poly(N-isopropyl acrylamide)s with core–shell morphology below the lower critical solution temperature

Abstract

Dilute poly(N-isopropyl acrylamide)s pass through a coil-to-globule transitions. Some hyperbranched compositions have biphasic core–shell morphologies with globular cores and open coil shells dependent on the degree of branching.

Analysis using size exclusion chromatography of poly( N -isopropyl acrylamide) using methanol as an eluent

“…INSET: Distributions obtained using polystyrene columns with: a. THF as eluent (see Supporting information) or b. previously published distributions using DMF as eluent [11].…”

The effect of hyperbranched poly(acrylic acid)s on the morphology and size of precipitated nanoscale (fluor)hydroxyapatite

“…Branched poly(acrylic acid) (PAA) was synthesised via reversible-addition fragmentation chain transfer (RAFT) polymerization using two different RAFT chain transfer agents: 4-vinylbenzyl pyrrole carbodithioate 18 (VPC, 1) and 4-vinylbenzyl dithiobenzoate 19 (VBD, 2). RAFT agents were chosen as they have both previously been demonstrated to produce branched polymers and are suitable form the polymerisation of acrylic monomers.…”

Highly branched poly(N-isopropyl acrylamide) functionalized with an inducer molecule suppresses quorum sensing in Chromobacterium violaceum

“…HB-PNIPAM with a ratio of NIPAM to branching units of 25 to 1 was prepared. 20 Homo-serine lactone was attached to the chain ends by amidation of the end groups (activated as N-hydroxysuccinimides) as shown in Fig. 1.…”

“…† As seen in previous studies of highly branched polymers the self-condensing vinyl polymerization produced a bimodal distribution with high dispersity. 20 However, after post functionalization the low molar mass portion is removed (alongside any unreacted residual AHL) via ultra-filtration leaving only the high molar mass fraction of the polymer. Conjugation of chain ends with HL led to a substantial increase in the average molar masses.…”

“…However, we have recently shown that several different functional end segments of this class of polymer can remain solvated in a core-shell morphology in which core is desovated but the shell is solvated before binding. 17,[19][20][21] In this coreshell structure or the fully desolvated state the chain ends of the polymer remain exposed to the solvent, thus ensuring that the HL groups are likely available for binding.…”