| 초록 |
Organic antimicrobial having high thermal stability was developed for food packaging applications. Most of organic antimicrobials have excellent antimicrobial properties. Their applications in plastic compounds, however, are strictly limited due to their low thermal stability. Thymol is extracted from thyme and used as an antimicrobial. When thymol is heated in a thermogravimetric analyzer (TGA), it is evaporated at 130oC, which is well below the processing temperature of plastics. To make thymol applicable to plastics, we placed thymol inside the supporting material which had a 3-d network structure. This network structure held thymol physically resulting in delaying the evaporation of thymol. Polyacrylamide (PAAm) is a super moisture absorbent and used as the supporting material in this development. The amount of thymol loaded inside PAAm was controlled by the variation of the amounts of cross linking agent and initiator. The thymol loaded PAAm was evaluated by the TGA and pyrolized GC/mass. We found that the temperature of thymol release was increased from 130oC to 280oC. The thymol loaded PAAm was compounded with polypropylene (PP) in a twin screw extruder and processed as a film. The morphology of dispersed antimicrobial and the releasing characteristics of thymol were evaluated. The antimicrobial property of the film was measured as well. |
