July 16, 2010
Ironing Out The Causes Of Wrinkles
Physicists find clues to the origin and evolution of wrinkles in thin sheets
As a sign of aging or in a suit, wrinkles are almost never welcome, but two papers in the current issue of Physical Review Letters offer some perspective on what determines their size and shape in soft materials.
In a related paper, Douglas Holmes and Alfred Crosby, also at the University of Massachusetts, Amherst quantify the transition from soft wrinkles to sharper folds. Similar to lifting a tissue from a box, they pull up an elastic sheet floating in water, and image the sheet as first wrinkles, and then folds, appear. They show that folds, like the edges of a neatly made bed, strain the sheet and smooth out the wrinkles.
The experiments offer complimentary insights into how defects, such as an edge or a fold, influence the presence of wrinkles and could prove helpful in understanding the formation of wrinkles in biological tissue.
Image Caption: This thin plastic sheet is floating on liquid wrinkles under stress. Physicists hope experiments such as these will help develop new models to explain how other materials wrinkle. Credit: Jiangshui Huang, Benny Davidovitch, Christian D. Santangelo, Thomas P. Russell, and Narayanan Menon, University of Massachusetts, Amherst
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