Controlling bad odors.
U.S. Patent 8,927,078 Qanuary 6, 2015), "Encapsulated Activated Carbon and the Preparation thereof," Chieh-Chun Chau and William F. Patchen (Reynolds Consumer Products Inc., Lake Forest, Illinois, USA).
Garbage stinks, and stink reduction is good. Activated carbon is an effective adsorbent for odor reduction because of functionality and porosity. Small carbon particles are difficult to use, but they are useful fillers for plastics. However, when activated carbon is blended with a molten polymer, the molten polymer plugs up the pores and prevents sorption.
Chau and Patchen developed a masterbatch of encapsulated activated carbon particles for plastics and odor reduction. The activated carbon particles are encapsulated with a non-water-soluble, brittle amorphous polymer such as polystyrene. The encapsulating mixture also contains pore-forming additives such as calcium carbonate, magnesium hydroxide, and talc. The mixture with the carbon is extruded and pelletized for mixing with other plastics.
The activated carbon is only partially encapsulated with polymer, leaving voids. In addition, cracks in the encapsulant form pathways to the carbon pores. Thus the carbon retains its sorptive properties in the plastics. These pellets can be mixed with film resins and blown to form odor-reducing bags.
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|Title Annotation:||INDUSTRY PATENTS; activated carbon|
|Article Type:||Brief article|
|Date:||Apr 1, 2015|
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