both ends down. They then applied five layers of reflective gold nanoparticles—enough particles to induce reflectivity, but not enough to block light from passing through. Alternating layers of clear polyurethane were used to stick the particles to the plastic. Finally, the researchers untwisted the plastic. The plastic can be stretched and released tens of thousands of times, altering the degree of polarization when it's stretched and returning to normal when it's released. Read more
New hybrid polymers could herald third chapter in polymers history
A new class of material—hybrid polymers, which incorporate rigid and soft nano-scale compartments, the latter of which can be removed and regenerated—has been developed by researchers at Northwestern University (Evanston, IL). Capable of contracting and expanding like muscles and rapidly responding to environmental stimuli, the polymers could be used one day to develop implantable materials that function in a life-like way and for use in drug-delivery and energy-source applications. Read more
Sponge-like polymer graft may transform spinal surgery
Scientists have engineered biodegradable polymer grafts designed to repair damaged vertebrae in the spinal column. Typically, surgeons insert expandable titanium rods via minimally invasive surgery (MIS) to treat this condition.
Lichun Lu, PhD, of the Mayo Clinic, and her postdoctoral fellow, Xifeng Liu, PhD, sought a more affordable material that would work with the MIS approach. They found a material that could be dehydrated down to a size compatible with posterior spinal surgery, and, once implanted, would expand to replace the missing vertebrae through fluid absorption. Read more