Polyethylene surface treatment increases adhesion while preserving bulk strength

Researchers demonstrated a catalytic treatment that makes solid polyethylene adhere to polar surfaces up to 90-fold more strongly than untreated polyethylene while preserving bulk properties such as melting temperature and tensile strength, a Nature paper reports. The method converts surface chemical groups into ketones at a solid-liquid interface using 0.001 mol% iron catalyst, inexpensive oxidants and temperatures below 80 °C. Adhesion was up to 4-fold stronger than polyethylene treated uniformly at a comparable functionalization level. The researchers also demonstrated further chemical modification of the surface ketones to increase adhesive strength.