Conventional UV absorbers do not offer long-term coating protection as they degrade over time from sunlight and lose their efficiency. Despite the widespread interest in nanotechnology and the limited weathering protection, conventional organic UV light absorbing materials still dominate the market used to protect coatings from outdoor exposure to UV light. In order to gain some insight into why nanotechnology has not significantly replaced conventional UV light stabilizers, SpecialChem asked its members in November the following question: What do you see as the major obstacle in using nanoparticles to enhance the weatherability of coatings?