Late Stage Domain Coarsening Dynamics of Lamellar Block Copolymers
Jack F. Douglas, Maninderjeet Singh, Wenjie Wu, Vinay Nuka, Joseph Strzalka, Alamgir Karim
Block copolymer (BCP) phase separation is an intriguing phenomenon whose dynamics can be expected to differ significantly from that of the polymer blends due to constraint of chain connectivity that limits the ultimate scale of phase separation and the emergence of elasticity in the ordered BCP state. BCP phase separation dynamics has been studied computationally, but there has been little experimental evidence to confirm the predicted BCP domain growth scaling laws. Here, we demonstrate the dynamics of late-stage lamellar BCP domain coarsening and show that the scaling exponent for domain growth is ≈ 1/6 (0.17) irrespective of the annealing temperature, which is close to the scaling exponent of 0.2 shown by theoretical studies. Furthermore, we show that the pre-factors in the domain coarsening equation show Arrhenius dependence on temperature indicating that the BCP domain growth dynamics is Arrhenius.