Interaction between poly(vinyl pyridine) and poly(2,6-dimethyl-1,4-phenylene oxide): A copolymer blend miscibility study

The phase behavior of blends of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) with random copolymers of styrene and 2-vinyl pyridine, Poly(S-co-2VP), as well as with random copolymers of styrene and 4-vinyl pyridine, Poly(S-co-4VP), has been investigated in order to estimate the values of the Flory–Huggins parameters χ PPO , 2 VP and χ PPO , 4 VP between PPO and 2-vinyl pyridine, resp. 4-vinyl pyridine. Using previously estimated values for the Flory–Huggins parameters 0.09 < χ S , 2 VP < 0.11 and 0.30 < χ S , 4 VP < 0.35 , together with the literature value of χ S , PPO = − 0.043 , the phase behavior observed as a function of the copolymer composition results in 0.11 ≤ χ PPO , 2 VP ≤ 0.12 and 0.46 ≤ χ PPO , 4 VP ≤ 0.48 . Insight in the interaction between PPO and poly(vinyl pyridine) is of considerable interest for several nanotechnology developments, since PPO is used to improve the mechanical properties of e.g. PS-block-P4VP nanorods.