Octa-armed star-shaped poly(ε-caprolactone)s with a phthalocyanine core by ring-opening polymerization: Synthesis and characterization

•Octa-armed star-shaped poly(ε-caprolactone)s with a phthalocyanine core were synthesized.•Viscosity properties of the 8SPCLs were investigated.•The aggregation and fluorescence properties of 8SPCL3 were studied.•Temperature and frequency dependent AC electrical conductivities of 8SPCLs were evaluated.•Thermal properties of 8SPCLs were identified by DSC and TGA.

A series of hydroxyl-terminated octa-armed star-shaped poly(ε-caprolactone)s (8SPCL1–3, represented as 5, 6 and 7, respectively) with an initiator core of 2,3,9,10,16,17,23,24-octakis(3-hydroxypropylmercapto)phthalocyaninatozinc(II) (4) was synthesized by the ring-opening polymerization of ε-caprolactone using tin(II) 2-ethylhexanoate as the catalyst. The obtained star-shaped polymers were characterized by FT-IR, 1H NMR, GPC and UV–vis spectroscopy. The measured intrinsic viscosities of all polymers were used to calculate the number-average molecular weight. The fluorescence of polymers 5–7 was studied. The changes in the visible spectra of 7 were investigated by increasing the concentration and adding methanol and cations such as Ag+, Hg2+, or Pb2+. The electrical conductivities of the polymers measured in vacuum and in air were between ∼10−9 and 10−6 S m−1. DSC and polarized optical microscopy techniques were used to evaluate the crystalline behavior of 5–7. The thermal stability of 5–7 was investigated by TGA.

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