Near infrared dye functionalized MWCNT as an effective initiator for the ring opening polymerization of ε-caprolactone

Multiwall carbon nano tube (MWCNT) was oxidized in the presence of mineral acid mixtures and further followed by the conjugation with near infra red dye (NIR dye). Thus obtained NIR dye functionalized MWCNT was characterized by various analytical techniques. The application of MWCNT-NIR dye system towards the ring opening polymerization (ROP) of ε-Caprolactone (C.L) was carried out by bulk polymerization method at 140 °C under inert atmosphere with the aid of stannous octoate (S.O) as a catalyst. The ROP was carried out at two different experimental conditions like variations in [M₀/I₀] and [C.L] in order to find out the structure–property relationship. The melting temperature (T_m) of the MWCNT-NIR dye end capped poly(caprolactone) (PCL) was increased with the increase in [M₀/I₀] values. The binding constant (K) between the MWCNT-NIR dye and PCL was determined by the UV-visible spectroscopy.