Suppliers of “low-odor” silicones for automotive interiors and children’s toys face rising complaints: products pass VOC tests yet emit faint chemical smells in real use.
The hidden culprit? Residual alkaline catalysts like KOH or tetramethylammonium hydroxide (TMAH). Though not VOCs, these can hydrolyze slowly or react with fillers, releasing ammonia-like notes detectable in sealed environments like new cars or toy packaging.
Standard GC-MS misses these ions. Ion chromatography (IC) reveals the truth—some batches show TMAH >8 ppm. Leading automakers now internally cap such residues at <5 ppm. Solution: multi-stage vacuum stripping, acid neutralization, and real-condition odor panels (e.g., 60°C for 7 days in sealed chambers).