Thermoresponsive polymers based on ring-opening metathesis polymerization

Abstract

A library of thermoresponsive polymers were developed with hydrophobic polynorbornene backbones and hydrophilic N-alkyl-amide/imide side groups, whose thermoresponsive behaviour in water could be conveniently tuned in a wide temperature range.

Aggregation-induced emission polymer nanoparticles with pH-responsive fluorescence

“…The monomers M1, M2 and M3 were synthesized according to our previously reported procedures. 33,34 The third generation Grubbs' catalyst dichlorodi-(3-bromopyridino)-N,N′-dimethylenoimidazolino-RuvCHPh (G3) was prepared according to the previously reported procedure. 35 Characterization 1 H-NMR and 13 C-NMR spectra were recorded on a Bruker Avance 400 spectrometer at room temperature.…”

Synthesis and Self-Assembly of Poly(vinylpyridine)-Containing Brush Block Copolymers: Combined Synthesis of Grafting-Through and Grafting-to Approaches

“…One major synthetic route for preparing brush BCPs is a grafting-through synthesis based on ring-opening metathesis polymerization (ROMP) of norbornenyl-functionalized macromonomers (MMs). ,,,− The development of the highly active Grubbs 3rd generation (G3) catalyst allowed for facile synthesis of ultrahigh molecular weight (co)­polymers and bottlebrushes. ,,, Despite this great success, the choice of MM for the ROMP is still limited, mainly due to the incompatibility of the G3 catalyst with certain MMs. − For example, ROMP of amine-containing polymers such as poly­( n -vinylpyridine) (P n VP) is not feasible − because P n VP itself interacts with the G3 catalyst and lowers the catalytic activity for ROMP. , However, considering the versatility of P n VP, which can chelate inorganic nanoparticles , and exhibit pH-responsiveness, − developing a synthetic route for incorporating side chains with such functionality is important.…”

“…In this regard, grafting-to synthesis − can be a promising approach for the synthesis of brush BCPs with tunable chain architecture, grafting density, and block composition depending on the choice of side chains. − , Several studies demonstrated the synthesis of brush BCPs by a copper-catalyzed azide–alkyne cycloaddition (CuAAC) click reaction to graft various side chains onto a pre-synthesized polymer backbone. ,, Importantly, the grafting-to method provides an alternative approach for incorporating unique side chain polymers that cannot be synthesized via ROMP. For example, Zhao and Zhang demonstrated the synthesis of polynorbornene with various N -alkyl substituted poly­(meth)­acrylamides side chains via an active ester substitution reaction . A recent work by Kim et al demonstrated a post-polymerization modification strategy to prepare pyridine pendant-containing brush BCPs through a click reaction of azide-terminated pyridine small molecules and alkynyl-functionalized polymeric side chains.…”

“…For example, Zhao and Zhang demonstrated the synthesis of polynorbornene with various N-alkyl substituted poly(meth)acrylamides side chains via an active ester substitution reaction. 29 A recent work by Kim et al demonstrated a post-polymerization modification strategy to prepare pyridine pendant-containing brush BCPs through a click reaction of azide-terminated pyridine small molecules and alkynyl-functionalized polymeric side chains. Nevertheless, this approach requires multiple synthetic steps with protection/deprotection of alkynyl groups.…”

Preparation of water-soluble hyperbranched polymers with tunable thermosensitivity using chain-growth CuAAC copolymerization

“…Thermoresponsive polymers as an important type of stimuliresponsive material have found extensive applications in drug delivery systems, hydrogel actuators, and smart surface coatings. 1,2 So far, most of the thermoresponsive polymers in the literature include N-and O-substituted poly(meth) acrylamide, [3][4][5][6][7][8] poly(meth)acrylate, [9][10][11][12][13] polyoxazoline, 14,15 poly (vinyl ether) 16,17 and polypeptide polymers. 18,19 Among these polymers, poly(ethylene oxide) (PEO)-based functional monomers and polymers are the most popularly studied because of their tunable lower critical solution temperature (LCST) and FDA-approved biocompatibility.…”