Hydroxypropylheptamethyltrisiloxane, ethoxylated, hydroxy-terminated
- Silicones
- CAS 67674-67-3
- IUPAC: hydroxypropylheptamethyltrisiloxane, ethoxylated, hydroxy-terminated
Hydroxypropylheptamethyltrisiloxane, ethoxylated, hydroxy-terminated (CAS 67674-67-3) appears in 2 of the 2,122 car-care products CarCareTruth tracks (as of August 2026).
No GHS classification at typical use concentrations in finished products. Silicone surfactants in this class are generally low toxicity.
Hydroxypropylheptamethyltrisiloxane, ethoxylated, hydroxy-terminated (CAS 67674-67-3) is a silicone trisiloxane surfactant used as a superspreading wetting agent in aqueous formulations. Unlike the cyclic silicones D4 (cyclotetrasiloxane) and D5 (cyclopentasiloxane), this is a linear trisiloxane backbone and does not carry the PBT (persistent, bioaccumulative, toxic) or vPvB (very persistent, very bioaccumulative) classification that affects the cyclic variants. Used in very low concentrations as a surface-spreading modifier.
Health & environment profile
- VOC
- no
- 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
- 5/5
Common questions about Hydroxypropylheptamethyltrisiloxane, ethoxylated, hydroxy-terminated
- What is Hydroxypropylheptamethyltrisiloxane, ethoxylated, hydroxy-terminated used for in car care?
- Silicone-based surfactant (trisiloxane) — wetting agent and surface modifier that lowers surface tension and enhances spreading of aqueous formulas on hydrophobic surfaces
- Is Hydroxypropylheptamethyltrisiloxane, ethoxylated, hydroxy-terminated a VOC?
- No. Hydroxypropylheptamethyltrisiloxane, ethoxylated, hydroxy-terminated is not classified as a volatile organic compound (VOC).
- Is Hydroxypropylheptamethyltrisiloxane, ethoxylated, hydroxy-terminated on California's Proposition 65 list?
- No. Hydroxypropylheptamethyltrisiloxane, ethoxylated, hydroxy-terminated is not on California's Proposition 65 list.
2 products contain this
Adam's Polishes Interior Detailer (Eucalyptus Mint)interior-detailer

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.