To gain insights into theoretical and experimental solubility parameters (SPs) while keeping in mind the general assumption that mainly hydrophobic block is responsible for drug loading, initially, we synthesized five different homopolymers which collectively comprised our triblock copolymers represented as hydrophobic pBuOx, pPentOx, pPrOzi, pBuOzi and hydrophilic pMeOx (Figure ). All of the homopolymers were synthesized by living cationic ring opening polymerization (LCROP) as previously described . The homopolymers were characterized by 1 H-NMR and GPC. The end-group analysis via 1 H-NMR gave a degree of polymerization of around 20 and 35 for hydrophobic and hydrophilic block, respectively (Figure to S5) which is very close to targeted block length. GPC elugram showed that purified homopolymers appeared essentially 10onomodal with reasonably low dispersity (Ɖ < 1.1) (Figure )