Easy access to high-melting sulfurated copolymers and their self-assembling block polymers from phenylisothiocyanate and oxetane

Although sulfurated polymers promise unique properties, their controlled synthesis, particularly when it comes to complex and functional architectures, remains challenging. Here, we show that the copolymerization of oxetane and phenyl isothiocyanates quantitatively forms polythioimidocarbonates with narrow molecular weight distributions (Mn = 5–80 kg/mol with Đ ≤ 1.2; Mn,max = 124 kg/mol). Studying their thermal properties through a specially developed self-nucleation procedure, high melting points up to 181 ºC are revealed for which π-stacking phenyl substituents and kinetically controlled linkage selectivity are key factors. Tolerance to macro-chain transfer agents and controlled propagation allows the synthesis of double crystalline and amphiphilic block copolymers that enables application in crystallization-driven self-assembly, an unventured territory for sulfurated copolymers.