MIT Researchers Develop Method for Making Perfectly Ordered Patterns of Microscale Wrinkles

Posted on August 2, 2012

MIT Researchers have developed a method for making perfectly ordered and repeatable surfaces with patterns of microscale wrinkles. The images above - taken with a 3-D microscope - show wrinkled surfaces produced using a method developed by the MIT team. The size, spacing and angles of the wrinkles vary depending on how much the original underlying surface was stretched, and how the stretching was released.

The researchers say the process uses two layers of material: "The bottom layer, or substrate, is a silicon-based polymer that can be stretched, like canvas mounted on a stretcher frame. Then, a second layer of polymeric material is deposited through an initiated chemical vapor deposition (iCVD) process in which the material is heated in a vacuum so that it vaporizes, and then lands on the stretched surface and bonds tightly to it. Then - and this is the key to the new process - the stretching is released first in one direction, and then in the other, rather than all at once."

Take a look:

The researchers say the method could be harnessed for a wide variety of useful structure. The say some of the possible structures include "microfluidic systems for biological research, sensing and diagnostics; new photonic devices that can control light waves; controllable adhesive surfaces; antireflective coatings; and antifouling surfaces that prevent microbial buildup."

Boyce, the Ford Professor of Engineering and head of MIT's Department of Mechanical Engineering, says, "One distinguishing feature of what we're showing is the ability to create deterministic two-dimensional patterns of wrinkles,such as a zigzag herringbone pattern. The deterministic nature of these patterns is very powerful and yields principles for designing desired surface topologies."

A paper describing this new process, co-authored by MIT postdocs Jie Yin and Jose Luis Yague, former student Damien Eggenspieler SM '10, and professors Mary Boyce and Karen Gleason, is being published in the journal Advanced Materials.

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