Background: Burning temperature is one of the most important factors affecting the
chemical structure of the smoke and the addition of reconstituted tobacco sheet to cut tobacco has been
widely used by the tobacco industry to reduce the cost of cigarettes and the health risks of smoking.
Methods: A flame retardant film, made from chitosan and ammonium polyphosphate, has been coated
on the surface of the reconstituted tobacco sheet substrate by Layer-by-Layer and spray coating
techniques. The thermal degradation properties and flame retardancy of these reconstituted tobacco
sheets were analyzed by TG-FTIR and micro-scale combustion calorimetry.
Results: It was found that the reconstituted tobacco sheet with the ratio of chitosan (5%) and ammonium
polyphosphate (3%) film coating showed significant reductions in the peak heat release rate
(50.7%), total heat release (35.8%) and the highest temperature in the temperature distribution diagram
(77°C). The main gases released during the pyrolysis of these reconstituted tobacco sheet samples
were H2O, CO2, CO, NH3, carbonyl compounds and the presence of film coating changed the
formation of evolved volatile products and formed less gaseous products except NH3 during the
thermal decomposition process.
Conclusion: The coating film can greatly enhance the char forming ability and reduce the flammability
of reconstituted tobacco sheet, and therefore, reduce the health risks of smoking with the addition
of these reconstituted tobacco sheets.