46f Well Ordered Polymer Melts from Low Molar Mass Surfactants upon Blending with Selectively Associating Additives

Vikram Daga1, Vijay R. Tirumala2, Curran Chandler3, Alvin H. Romang1, Eric Anderson3, Eric K. Lin2, and James J. Watkins4. (1) Department of Chemical Engineering, University of Massachusetts-Amherst, 159 Goessman lab, 686 N. Pleasant st, Amherst, MA 01003, (2) Polymers Division, National Institute of Standards and Technology, 100 Bureau Dr Stop 8541, Gaithersburg, MD 20899, (3) Polymer Science and Engineering, University of Massachusetts - Amherst, Amherst, MA 01003, (4) Department of Polymer Science and Engineering, University of Massachusetts, 120 Governors Dr., Amherst, MA 01003

Electronic materials have benefitted from a continual decrease in feature sizes over the last few decades resulting in reduction in size of the electronic components in parallel to higher computational speed and reduction in power consumption. The use of block copolymer melts as nanostructured templates with sub-10 nm domains in applications is limited by their low segregation strength (chi*N) and thus impractical (very low) order-to-disorder transition temperatures. Since increasing molar mass also increases the interdomain spacing, nanostructured periodic templates with sub-10 nm domains spacing can only be obtained by increasing the Flory-Huggins segment-segment interaction parameter, chi. Through an enhancement in the apparent chi, we have shown that disordered block copolymer surfactant melts with a molar mass less than 15 kg/mol can be induced to undergo disorder-to-order transition at practical processing temperatures yielding well-ordered morphologies with features having domains as small as 5 nm when blended with a selectively associating homopolymer. Examples of the block copolymer surfactants include commercially available copolymers such as poly (oxyethylene-oxypropylene-oxyethylene) (Pluronics) and poly(ethylene-oxyethylene) (Brij). Examples of homopolymers included poly (acrylic acid), poly (4-vinyl phenol) and poly (styrene sulfonate). We have studied the effect of homopolymer molar mass on the segregation of a disordered Pluronics resulting in lamellar, cylindrical and spherical morphologies in the ordered phase. The ability to generate well defined morphologies using additives having various chemical and physical functionalities further enable subsequent modification of the templates and thus pathways to a variety of applications.