Synthesis and Structural/Physical Properties of Well-Defined Linear and Star-Shaped Polysulfides Constructed by Controlled Insertion Reaction of Thiirane and Carbamic Acid Thioester

Well-defined linear polysulfides and star-shaped polysulfides were synthesized and characterized. Controlled insertion reaction of phenoxypropylene sulfide (PPS) and S-(4-methoxyphenyl)carbamic acid thioester (PCPOMe) in the presence of tetrabutylammonium chloride (TBAC) in 1-methyl-2-pyrrolidone (NMP) at 60 °C for 20 h afforded corresponding well-defined linear polysulfides poly[PC-(PPS)n-POMe] (n = 10–50) in satisfactory yields. Core-gel type star-shaped polysulfides, star-{poly[PC-(PPS)n-POMe]-PBT(3.0)core}, were obtained by the reaction of poly[PC-(PPS)n-POMe] (n = 10, 20, and 30) and 2,2-bis(phenoxypropylene sulfide)propane (PBT). The thermal stability, refractive index, and hydrophobicity of star-{poly[PC-(PPS)n-POMe]-PBT(3.0)core} were greater than those of corresponding-arm poly[PC-(PPS)n-POMe]. Small-angle X-ray scattering (SAXS) structure analysis using Berry and Kratky plots showed that the synthesized star-{poly[PC-(PPS)n-POMe]-PBT(3.0)core} has 9–16 arms and a radius of gyration (Rg) of 3.3–4.2 nm. Fitting the Kratky plot with a core-gel wormlike star model indicated that the star-{poly[PC-(PPS)n-POMe]-PBT(3.0)core} has a maximum core radius of 1.6–2.7 nm.