Comparison of the selective retention capacity of cigarette filters made from cellulose acetate and polypropylene
A large number of cigarettes in the Chinese market utilize polypropylene filters. This study was undertaken in order to determine the difference in filtration capabilities between polypropylene and cellulose acetate.Comparable cigarettes based on filters cellulose acetate and polypropylene with the same physical parameters have been prepared and tested for smoke analysis. Besides tar, smoke-nicotine and CO selected compounds in the smoke of these cigarette have been determined and now give a picture of the different filtration behaviour of cellulose acetate and polypropylene. The data suggest that the filtration mechanism for the particulate phase of tobacco smoke is similar for both polypropylene and cellulose acetate. Tar delivery is highly predicable for cellulose acetate cigarette filters based in well-established models, and the same should be true for polypropylene (although a different model may apply). However, the retention behaviour for selected smoke constituents is apparently different for polypropylene filters vs. those constructed from cellulose acetate. This is not surprising: polypropylene is used in many applications that take advantage of its low physical-chemical interactivity. On the other hand, cellulose acetate displays a moderate polarity and has, in fact, traditionally been used as a chromatographic medium. The ability of cellulose acetate to reduce the delivered amounts of phenols, volatile N-nitrosamines, pyridiene, etc., is especially important in light of the recent interest in this class of compounds. It should also be noted that the smoke components measured and discussed here are only a very small subset of the actual components that constitute cigarette smoke. It is very likely that this observed difference in the selective retention behaviour of the two types of filters extends also to some other compounds of tobacco smoke. Therefore, these two filter types will also have an influence on cigarette performance, like impact and taste. This can affect product acceptability and needs to be considered in cigarette design.