It’s a familiar situation: you spent just five minutes in a coffee shop or next to a fire, but your coat and scarf keep that spirit going for days. It seems that some things literally attract amber to themselves, refusing to part with it. This phenomenon is explained not by “caustic” chemistry, but by simple physical laws of surface interaction.
Smell is volatile moleculeswhich break away from the source and travel through the air. When they encounter an obstacle, one of two processes occurs: they either bounce or get stuck. How firmly the aroma sticks to the surface depends on material structure. Smooth objects, like glass or metal, do not trap molecules, so they are easy to clean.
Fabrics, wood and paper work differently because of their porosity.
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Fibers of natural fabrics (cotton, wool, linen) under a microscope look like loose, scaly ropes.
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Huge surface area inside these fibers allows billions of aromatic molecules to “park” in microscopic voids.
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A process is taking place adsorption — retention of gas on the surface of a solid.
Another important factor is chemical affinity. Many strong odors (especially kitchen odors) are oil-based. Fat molecules are hydrophobic and adhere perfectly to the same hydrophobic synthetic fibers or simply “stick” to any rough surface. If there are fat particles in the air (for example, during frying), they work like glue, firmly fixing the aroma on curtains and clothes.
Humidity also plays the role of an amplifier. Water molecules can transport aromatic compounds. When wet clothing dries, the water evaporates and the heavy scents remain deep within the fabric, as if preserved.
Heat makes the situation worse. When the temperature rises (for example, in hot water or in a warm room), the pores of the materials expand, allowing the smell to penetrate even deeper. When the item cools, the pores narrow, trapping the molecules inside.
It is difficult to get rid of ingrained odor precisely because of the mechanical stuckness of particles deep in the fibers. Conventional ventilation only helps remove the surface layer of molecules, but does not affect what is hidden inside the structure. Complete odor removal is only possible by breaking the bonds between the odor molecule and the material, most often through washing or chemical neutralization.
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