Influence of cyclodextrin on the solubility of a classically prepared 2-vinylcyclopropane macromonomer in aqueous solution

Abstract

SummaryA macromonomer 5 consisting of a polymerizable vinylcyclopropane end group and a poly(N-isopropylacrylamide) (poly(NiPAAm)) chain was obtained from amidation of 1-ethoxycarbonyl-2-vinylcyclopropane-1-carboxylic acid (4) with an amino-terminated poly(NiPAAm) 3 as an example. This macromonomer 5 showed an LCST effect after complexation of the vinyl end group with ß-cyclodextrin in water. Via radical ring-opening copolymerization of 5 and NiPAAm a graft copolymer 8 with a clouding point of 32 °C was synthesized. The branched unsaturated polymer was treated with ozone to cleave the double bonds of the main chain.

Supramolecular control over thermoresponsive polymers

“…Amphiphilic host molecules, such as cyclodextrins, featuring a hydrophilic outer shell and a hydrophobic cavity, can complexate with hydrophobic guests present in a thermoresponsive polymer, thereby increasing its hydrophilicity and T CP . Many examples have been reported on complexation of cyclodextrins with endgroup guest-functionalized thermoresponsive polymers, including PNIPAAm-azo dye [83], PNIPAAm-vinylcyclopropane [84], or poly(N,N-diethylacrylamide)-4-alkylphenol with methylated bCDs [85]. As expected, T CP variations were found to be dependent on the excess of cyclodextrin host added, and typically increased by less than 5 K, although a T CP increase of close to 10 K was observed in a tert-butyl phenyl-terminated poly(N,N-diethylacrylamide) (PDEAAm) thermoresponsive polymer in the presence of 2 equiv.…”

Complexation of thermoresponsive dialkoxynaphthalene end-functionalized poly(oligoethylene glycol acrylate)s with CBPQT4+in water

“…33 The end-functionalization of thermoresponsive polymers with various hydrophobic guest molecules and the interaction of these hydrophobic end-groups with supramolecular hosts has been shown to be an effective way to alter polymer phase transition temperatures. [34][35][36] For example, β-cyclodextrin has been exploited to tune the LCST of end-functionalized PNIPAMs bearing a pyrenyl group by the selective complexation of hydrophobic chain ends, resulting, due to the masking effect of the hydrophilic host molecule, in an increase of the T CP of polymers. 37 Woisel and co-workers have shown that the LCST phase transition temperature of 1,5-dialkoxynaphthalene-terminated PNIPAM could be increased by ca.…”

Supramolecular glycopolymers with thermo-responsive self-assembly and lectin binding

“…Importantly, the authors nicely demonstrated that the livingness of a RAFT process depends on the knowledge of polymerization kinetics. 24 The assembly of new polymeric structures by non-covalent interactions, such as hydrogen bonding, ligand-metal coordination or "host-guest" inclusion complexation, has recently attracted considerable interest. Interest in smart polymers has remained high over many decades, displaying great promise in numerous nanotechnological and biomedical applications.…”