Researchers from North Carolina State University have
developed a way to melt or “weld” specific portions of polymers by embedding
aligned nanoparticles within the materials. Their technique, which melts fibers
along a chosen direction within a material, may lead to stronger, more
resilient nanofibers and materials.
Physicists Jason Bochinski and Laura Clarke, with materials
scientist Joe Tracy, placed specifically aligned gold nanorods within a solid
material. Gold nanorods absorb light at different wavelengths, depending upon
the size and orientation of the nanorod, and then they convert that absorbed
light directly into heat. In this case, the nanorods were designed to respond
to light wavelengths of 520 nanometers (nm) in a horizontal alignment and 800
nm when vertically aligned. Human beings can see light at 520 nm (it looks
green), while 808 nm is in the near infrared spectrum, invisible to our eyes.