Polyphenols, which by the Quideau
definition are plant-derived
chemicals with two or more phenolic groups, have attracted interest
because of their antioxidant activity, adsorption on universal substrates,
and biocompatibility. Most polyphenols include gallol groups in their
chemical structures, which has inspired us to synthesize gallol-functionalized
polymers. We report the reversible addition–fragmentation chain
transfer polymerization of 3,4,5-trimethoxystyrene using cyanomethyl
dodecyl trithiocarbonate as the chain transfer agent. This method
produces well-defined polymers with a wide range of molecular weight
(from 5.4 to 53.4 kg mol<sup>–1</sup>) and low polydispersity
index (<i>M</i><sub>w</sub>/<i>M</i><sub>n</sub> < 1.3). Subsequent demethylation of poly(3,4,5-trimethoxystyrene)
(PTMS) yields poly(3,4,5-trihydroxystyrene) (polyvinylgallol, PVGal).
These newly synthesized polymers exhibit greater antioxidant activities
than widely used catechol-functionalized polymers based on the 2,2-diphenyl-1-picrylhydrazyl
radical (DPPH), 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic
acid) (ABTS), and oxygen radical absorbance capacity (ORAC) methods.
Also, PVGal showed better adsorption properties on metals and SiO<sub>2</sub> substrates than those of the other phenolic polymers. Given
these high antioxidant and adsorption properties, the effective use
of gallol-funcationalized polymers in biomaterials is expected
