Open-aired synthesis of star-shaped poly[2-(methacryloyloxy)ethyl trimethylammonium chloride]

A series of star-shaped poly[2-(methacryloyloxy)ethyl trimethylammonium chloride]s with different arm lengths were synthesized via open-aired enzymatically assisted ATRP using the 2-hydroxypropyl β-cyclodextrin derivative as an initiator. The resulting PMETAs with narrow molecular weight distribution (Đ = 1.06-1.12) created thin hydrophilic films with thickness < 40 nm exhibiting water contact angle (WCA) values < 50°. Higher interfacial tension values obtained for star-shaped polymers in comparison with the linear analog indicate that surface wettability can be modified by changing the polymer topology. AFM was used to analyze the relationship between macromolecule topology, surface roughness, and WCA.