The continuous insertion reaction of phenoxypropylenesulfide (PPS) into the thioester moieties of calixarene derivatives (cores) generated from p - tert -butylthiacalix[4]arene (BTC[4]), 2,8,14,20-tetramethylcalix[4]resorcinarene (CRA[4]), and 2,8,14,20-tetra(4-hydroxybenzen-1-yl)calix[4]resorcinarene {CRA(Ar-OH)[4]} proceeded smoothly with tetrabutylammonium chloride (TBAC) as a catalyst to give well-defined star-shaped polysulfides with 4, 8 and 12 arms. The arm length and sulfur content of the star-shaped polysulfides were controlled by the feed ratio of PPS and core. The refractive-index values ( n D ’s) of the synthesized star-shaped polysulfides were determined in the film state by means of ellipsometry; the n D ’s increased with increasing numbers of arms, length of arms, and sulfur content and with decreasing size of the core structure.
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Kudo et al. (2009) studied this question.
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