Morphology of Films of SEBS Triblock Copolymers
摘要
Surface morphologies of the films of poly (styrene-6-(ethylene-cp-butene)-b-styrene) (SEBS) have been studied by using tapping-mode atomic force microscopy (TM-AFM). The films of block copolymer were prepared both by spin-coating on mica and by solvent-casti ng on different solution surfaces. For spin-coating samples, the effect of solution concentration, solvent, and annealing temperature are investigated. It is shown that changing the concentration of the solution makes no difference on the morphology of the film of the block copolymer. The microstructures are quite stable during thermal annealing; only the size of the domains changes toward the equilib- rium configuration. However, solvent annealing can notably change the microstructures. When different selective solvents are used for film spin-coating, different morphologies can be obtained and explained by the different solu- bility parameters of the solvents. As expected, significant different morphologies in the top and the bottom surfaces of the casting films were observed. The images of the top surfaces reveal cylinder microdomains, while those of the bottom surfaces were spherical morphologies. Keywords atomic force microscopy (AFM), morphology, block copolymer, spin-coating, solvent-casting