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Siloxanes contaminate everything. We routinely see them on various surfaces when doing X-ray photoelectron spectroscopy.
by s0rce 4mo ago
Siloxanes contaminate everything. We routinely see them on various surfaces when doing X-ray photoelectron spectroscopy.
- isoprophlex 4mo agoIndeed. "Grease peaks" we called them, they were always there in basically all NMR or MS spectra I took as an organic chemist. Like PFAS or microplastics, you just can't get rid of them.
- mrob 4mo agoYou can see this grease by the effect it has on water contact angle. If you have a smooth glass/metal/ceramic surface, cleaned by a highly effective method (e.g. an ultrasonic cleaner), water poured on it will slide off easily without forming beads ("water-break test"). But if you leave it out in ordinary air for some time, the water will form beads again even if you never touch it. Exact time varies depending on air quality, but probably within a few hours.
- s0rce 4mo agoThat's not always siloxanes, just atmospheric hydrocarbons.
- cubefox 4mo agoI bet some of these modern environmental contaminants is causing the increasing age cohort cancer rates.
- awakeasleep 4mo agoLook up the biocompatibility and safety profiles of siloxanes
- cubefox 4mo agoYeah probably one of the others.
- ericd 4mo agoApparently we also put polydimethylsiloxane in deep frying oil. Wonder what that does to our innards.