Suppression of Phase Separation Pattern Formation in Blend Films With Block Copolymer Compatibilizer
Li Piin Sung, Jack F. Douglas, Charles C. Han, Alamgir Karim
We show that the addition of a small concentration of a block copolymer surfactant to a thin phase separating blend film can suppress the pattern formation that occurs in the blend films without block copolymer. This effect is observed even at very low block copolymer concentrations which are below the bulk critical micelle concentration. The block is distributed uniformly on average in the direction normal to the substrate, but we observe large scale fluctuations in the film darkness in optical micrographs that has the appearance of large scale critical fluctuations. We attribute the film thickness to a reduction of the interfacial tension that gives rise to the surface pattern formation in the absence of the surfactant and the diffuse intensity patterns are ascribed to fluctuations in the block copolymer concentration within the film.
, Douglas, J.
, Han, C.
and Karim, A.
Suppression of Phase Separation Pattern Formation in Blend Films With Block Copolymer Compatibilizer, Journal of Polymer Science Part B-Polymer Physics, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=852060
(Accessed February 25, 2024)