Traceability of VOCs in tire inner liner by chromatography-mass spectrometry

Many parts of the vehicle cabin generate volatile organic compounds (VOCs), and some are hazardous and/or odorous to humans. In this study, VOCs in the inner liner of automobile spare tire, including raw rubbers and resins, were detected by gas chromatography-mass spectrometry (GC-MS) coupled with an extracting method of static headspace sampling (SHS). The results demonstrated that the sources of VOCs can be traced back to raw rubbers and resins: alkylphenol resins can release a large amount of 2,4,4-trimethyl-1-pentene and 2,2,4,6,6-pentamethyl-3-heptene; chlorobutyl rubber (CIIR) contained 3-methyl-pentane, and methyl-cyclopentane, and these VOCs are odorous. When alkylphenol resin and natural rubber (NR) with low VOCs were used to replace the corresponding resin and NR in the initial formulation, the total volatile organic compounds (TVOCs) in the inner liner could be reduced. We expected that the information gained from this work could provide a basic reference for the manufacture of environmental-friendly tire products.