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CarCareTruth

Dimethoxydimethylsilane

  • Ceramic (SiO₂)
  • CAS 1112-39-6
  • IUPAC: dimethoxy(dimethyl)silane

Dimethoxydimethylsilane (CAS 1112-39-6) appears in 2 of the 2,122 car-care products CarCareTruth tracks (as of August 2026). It is classified as a VOC.

Low acute toxicity at the concentrations present in ceramic coatings (<0.2%). Releases methanol on hydrolysis — methanol is a CNS toxicant and optic-nerve toxin at high doses (H331/H311/H370) but the quantity released from sub-0.2% alkoxysilane in a coating is toxicologically trivial. No sensitizer, carcinogen, or Prop 65 classification. The carrier solvents in formulations containing DMDMS (naphtha, Stoddard) present a greater hazard than the alkoxysilane component.

Dimethoxydimethylsilane (DMDMS, CAS 1112-39-6) is a short-chain difunctional alkoxysilane used as a reactive crosslinker and surface-modification agent in specialty coating formulations such as CarPro Cquartz UK 3.0. Present at trace levels (0.1–<0.2%), it participates in the sol-gel condensation chemistry that builds the silicone-oxide network in cured ceramic coatings.

Health: On hydrolysis, releases methanol (two methoxy groups) and dimethylsilanediol. At the concentrations present in finished coatings, the released methanol quantity is negligible relative to occupational exposure limits. No sensitizer or carcinogen classification. Not a Prop 65 substance.

Environment: Not classified as aquatically toxic. The hydrolysis products (methanol + dimethylsilanediol) are water-soluble and subject to further environmental breakdown. The silanol condensate ultimately forms silica-like material that integrates into the cured coating surface.

Health & environment profile

VOC
yes
Prop 65 listed
no
Asthmagen
no
EPA Safer Choice
no
Aquatic toxicity
no
Biodegradable
no
Bioaccumulative
no
Persistent
no
Ozone depleting
no
Microplastic
no
PFAS
no
Env. score
4/5
Purpose: Reactive difunctional alkoxysilane crosslinker that condenses into the SiO₂ network of cured ceramic coatings

Common questions about Dimethoxydimethylsilane

What is Dimethoxydimethylsilane used for in car care?
Reactive difunctional alkoxysilane crosslinker that condenses into the SiO₂ network of cured ceramic coatings
Is Dimethoxydimethylsilane a VOC?
Yes. Dimethoxydimethylsilane is classified as a volatile organic compound (VOC).
Is Dimethoxydimethylsilane on California's Proposition 65 list?
No. Dimethoxydimethylsilane is not on California's Proposition 65 list.

2 products contain this

Related

Health and environment notes translate the manufacturer Safety Data Sheet, the GHS classification, and authoritative regulatory listings (California Prop 65, EPA). Not medical advice. They describe the ingredient itself; whether a hazard applies to a finished product depends on its concentration and how it's used.