Spreading of diblock copolymer droplets: A probe of polymer micro-rheology

We present an experimental study of the spreading dynamics of symmetric diblock copolymer droplets above and below the order-disorder transition. Disordered diblock droplets are found to spread as a homopolymer and follow Tanner’s law (the radius grows as R ∼ tm , where t is time and m = 1/10 . However, droplets that are in the ordered phase are found to be frustrated by the imposed lamellar microstructure. This frustration is likely at the …