Bioinspired Materials for Self-Cleaning and Self-Healing
- PDF / 1,003,828 Bytes
- 10 Pages / 612 x 792 pts (letter) Page_size
- 80 Downloads / 243 Views
Basics of Wettability
Jeffrey P. Youngblood and Nancy R. Sottos, Guest Editors Abstract Biological systems have the ability to sense, react, regulate, grow, regenerate, and heal. Recent advances in materials chemistry and micro- and nanoscale fabrication techniques have enabled biologically inspired materials systems that mimic many of these remarkable functions. This issue of MRS Bulletin highlights two promising classes of bioinspired materials systems: surfaces that can self-clean and polymers that can self-heal. Self-cleaning surfaces are based on the superhydrophobic effect, which causes water droplets to roll off with ease, carrying away dirt and debris. Design of these surfaces is inspired by the hydrophobic micro- and nanostructures of a lotus leaf. Self-healing materials are motivated by biological systems in which damage triggers a site-specific, autonomic healing response. Self-healing has been achieved using several different approaches for storing and triggering healing functionality in the polymer. In this issue, we examine the most successful strategies for self-cleaning and self-healing materials and discuss future research directions and opportunities for commercial applications.
Introduction The extraordinary properties and functions of biological systems provide a new paradigm for the design and fabrication of engineering materials.1–3 Biologically inspired synthesis, hierarchical structuring, and stimuli-responsive materials chemistry have enabled materials systems with unprecedented function. Many exciting bioinspired materials concepts are currently under development, such as composite materials with nacre-like flaw tolerance,4,5 gecko-inspired reversible adhesives,6,7 and advanced photonic structures that mimic butterfly wings.8 This issue of MRS Bulletin focuses on two remarkable examples of materials with demonstrated bioinspired function: selfcleaning surfaces and self-healing polymers. Self-cleaning materials are based on the superhydrophobic effect whereby water drops show nearly spherical profiles (contact angles of ~180°).9,10 Superhydrophobic surfaces are generally designed on principles at work in the lotus leaf where the surfaces have hydrophobic micro- and nanostructures that suspend
732
effect,” whereby water droplets are shed easily from certain structures, carrying away dirt and other debris.11–13 Such bioinspired topographical methods toward self-cleaning are the focus of this review.
water droplets.11–13 Self-healing materials are inspired by living systems in which minor damage (e.g., a contusion or bruise) triggers an autonomic healing response. Successful healing relies on seamless integration of reactive chemical functionality into a polymer or polymer composite at the microscale, nanoscale, or molecular level. Although these two functions are quite different, together they represent the wide range of autonomic responses achievable through bioinspired design. In this article, we separately introduce the key elements of self-cleaning and self-healing materials systems
Data Loading...
