“Smart” Adhesion: Controlling Polymer Interfaces with Patterns

1. “Smart” Adhesion: Controlling Polymer Interfaces with Patterns Alfred J. Crosby, University of Massachusetts, DMR 0349078 Nature has shown through examples like the gecko and jumping spider that adhesion can be enhanced and tuned through the combination of geometric patterns and materials properties. Following these examples, we are exploring the fundamental relationship between material : pattern : adhesion. A recent highlight has been our use of the natural phenomenon of surface wrinkling (fig. a) to generate patterns that directly control adhesion. Stable surface wrinkles in soft, polymer surfaces can provide adhesion enhancement when the wrinkles are designed with the correct size (fig. b), which is related to the properties of the materials at the interface. Custom instruments allow us to visualize wrinkle contact (fig. c) while measuring interfacial strength. These results indicate the potential for surface wrinkling, a scaleable, self-assembling fabrication method, to define “smart” coatings that can be used in a range of applications from anti-fouling surfaces to transdermal drug delivery. References Chan, E.P., Smith, E., Hayward, R. and Crosby, A.J.* “Surface Wrinkles for ‘Smart’ Adhesion,” Advanced Materials, accepted, 2007.

2. “Smart” Adhesion: Controlling Polymer Interfaces with Patterns Alfred J. Crosby, University of Massachusetts, DMR 0349078 Education Through Research Total Group: 3 undergraduates (bottom right), 8 Ph.D. students, 2 post-doctoral researchers, and 3 researchers through the NSF-MRSEC Research Experience for Teachers (RET). Through funding of this NSF-DMR CAREER award and supplemental funding, we provide an active environment that teaches science through research at all levels. An undergraduate researcher led the initial measurements on wrinkles controlling adhesion, and she is listed as co-author on this publication that was recently accepted in a high-impact journal. RETs are currently researching surface wrinkling and have identified an interesting method for aligning surface wrinkles across large areas. These results are being prepared by the RETs for publication in a peer-reviewed materials journal, and they will be preparing a manuscript to describe the classroom-friendly methods that they developed to teach connect math, physics, and art for middle and high school students through wrinkling methods. This undoubtedly will have direct impact on the inspiration and training of future materials scientists. Preparing Researchers Through Education This grant has been used to develop a course focused on training science-related graduate students in “soft” skills and management strategies to increase success in post-graduate careers. Topics include: leadership, proposal writing, group management, communication in diverse environments, and ethics. In Spring 2007, this course entered its fourth year and continues to grow in students and diversity. Leading with Service Associate Director of Education and Outreach for UMass NSF-MRSEC Member College of Natural Sciences and Mathematics Diversity Comm. Member Univ. of Mass. Community, Diversity, and Social Justice teams