(174be) Two-Membrane Air Fresheners for Enhanced Non-Energized Perfume Delivery

We have developed two-membrane air fresheners for continuous non-energized air freshener perfume delivery with significantly superior delivery consistency over a conventional membrane air freshener. In this study, a model perfume is used to investigate the conventional air freshener as functions of temperature and air velocity. The release rate of the conventional air freshener varies greatly from its initial use to its end-of-life under a fixed ambient condition. In order to regulate the evaporation rates of the volatile compounds, the new air freshener consisting of an inner membrane and an outer membrane. The outer membrane is used as the regulation membrane to create a vapor reservoir between the inner wet membrane and the outer membrane so that the vapor generated from the inner membrane can be regulated. Comparing the conventional air freshener to the new air freshener, the outer membrane impregnated with polyethylene glycol (PEG) shows significantly better consistency of perfume delivery rates under different air velocities and temperatures. In addition, a model has been employed to predict the perfume release from the conventional air freshener. The perfume release from the newly developed air fresheners is regulated by vapor transport through the outer membrane which may be predicted through the Knudsen flow or solution diffusion model.