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Silanol Terminated Polydimethylsiloxane

  • Silicones
  • CAS 70131-67-8
  • IUPAC: α,ω-Dihydroxypoly(dimethylsiloxane)

Silanol Terminated Polydimethylsiloxane (CAS 70131-67-8) appears in 2 of the 2,122 car-care products CarCareTruth tracks (as of August 2026).

No GHS hazard classification. Silanol-terminated PDMS is a high-molecular-weight silicone polymer with no known acute or chronic health effects at use concentrations in car care products.

Silanol terminated polydimethylsiloxane is a linear silicone polymer with hydroxyl (silanol) end groups. The end groups allow it to bond more readily to surfaces compared to standard non-reactive PDMS. Used as a surface modifier in quick detailers and spray waxes to provide lubricity, gloss, and light water beading without leaving a greasy film.

The compound is not biodegradable (silicone persistence in environment) but has no aquatic toxicity classification and no known health hazards at detailing product concentrations.

Health & environment profile

VOC
no
Prop 65 listed
no
Asthmagen
no
EPA Safer Choice
no
Aquatic toxicity
no
Biodegradable
no
Bioaccumulative
no
Persistent
yes
Ozone depleting
no
Microplastic
no
PFAS
no
Purpose: Reactive linear silicone polymer — surface modifier that deposits a smooth, slick film on paint and glass; contributes to lubricity and water beading

Common questions about Silanol Terminated Polydimethylsiloxane

What is Silanol Terminated Polydimethylsiloxane used for in car care?
Reactive linear silicone polymer — surface modifier that deposits a smooth, slick film on paint and glass; contributes to lubricity and water beading
Is Silanol Terminated Polydimethylsiloxane a VOC?
No. Silanol Terminated Polydimethylsiloxane is not classified as a volatile organic compound (VOC).
Is Silanol Terminated Polydimethylsiloxane on California's Proposition 65 list?
No. Silanol Terminated Polydimethylsiloxane 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.