Shape-Tunable Polymer Nanofibrillar Structures by Oblique Electron Beam Irradiation

Original entry: William Bonificio, AP 225, Fall 2009

Information

Shape-Tunable Polymer Nanofibrillar Structures by Oblique Electron Beam Irradiation Tae-il Kim, Changhyun Pang, Kahp Y. Suh Langmuir 2009 25 (16), 8879-8882

Soft matter keywords

Shape tuning, nanofibrils, adhesion strength, nanovelcro

Summary

The researchers in this experiment were able to tune the shape of polymer nanofibrils using a very accessible and easy method. First they produced a polyurethane acrylate (PUA) nanofibril structure. Then, by bombarding the polymer with electrons at a shallow angle, the nanofibril structure begane bending over forming small hooks. The researchers forsee applications for adhesion as the stuctures resemble gecko setae, or 'nanovelcro'.

Soft matter discussion

The production of a the nanofibril stuctures beginning with a silicon master. As shown, the area of surface of the nanofibril that is bombarded with electrons effects the overall final structure of either stooped fibrils and crispated fibrils.

The top two photos show the silicon template used to create the PUA nanofibrils. Below that is finished PUA nanofibrils. Below that show the two shape tuned nanofibrils, the left is the stooped fibril structure, while the right is the crispated fibril structure.