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Silicone Fluids & Oils Available — Bulk Only

Liquid Silicone Rubber (LSR)

PDMS-OH
CAS 70131-67-8 · Formula HO

A pumpable silicone elastomer that molds into flexible, thermally stable parts. It cures into a heat-, cold-, and weather-resistant rubber used for molded seals, gaskets, and O-rings, for electrical insulation and encapsulation, and for flexible molds and heat-resistant housewares.

Part of Silicone Processing Aids · Silicone Fluids & Additives
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HS Code
3910.00
At a Glance
Material Family
Silicone Fluids & Oils
Record Type
Pure compound
Primary Role
Crosslinking / Curing · Film Formation
Functional Roles
Crosslinking / Curing Film Formation Lubrication Slip / Release
INCI Name
DIMETHICONOL
CosIng Functions
ANTIFOAMINGMOISTURISINGSKIN CONDITIONING - EMOLLIENT
Industries Served
Coatings & Construction Industrial Manufacturing Plastics & Polymers Textiles
Applications & Use Cases
  • ▸ Molded parts: Seals, gaskets, and O-rings via injection or compression molding.
  • ▸ Electrical: Insulation, encapsulants, and potting for electronics.
  • ▸ Tooling: Flexible molds for casting resins.
  • ▸ Housewares: Heat-resistant kitchenware and bakeware.
Physical Properties
Appearance
Clear colorless to slightly hazy viscous liquid (typical)
Physical State
Liquid (typical)
Viscosity
20 to 150000 cSt depending on grade (typical)
Specific Gravity
0.96 to 0.98 (typical)
Flash Point
>100 C (typical, grade dependent)
Solubility in Water
Insoluble (typical)
Silanol Content
0.03 to 4.5 percent OH depending on chain length (typical)
Safety & Handling
Full SDS available on request

A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.

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HS / Tariff Classification
Harmonized System (HS) Code — 6-digit international heading
3910 . 00
Chapter 39
Plastics and articles thereof
Heading 39.10
Internationally harmonized (WCO HS)
Subheading 3910.00
6-digit international code — national tariff line adds further digits
Chemical Identity
CAS Number
70131-67-8
Molecular Formula
HO
INCI Name
DIMETHICONOL
Synonyms & Trade Names
Silanol-terminated polydimethylsiloxane Siloxanes and Silicones, di-Me, hydroxy-terminated Hydroxy-terminated PDMS OH-terminated polydimethylsiloxane Silanol-terminated PDMS Dimethylsiloxane, hydroxy-terminated polymers Silanol fluid
Full Description

Liquid silicone rubber (CAS 70131-67-8) is a polydimethylsiloxane-based silicone elastomer. It cures into a heat-, cold-, and weather-resistant rubber used for molded seals, gaskets, and O-rings, for electrical insulation and encapsulation, and for flexible molds and heat-resistant housewares.

Frequently Asked Questions

What is liquid silicone rubber used for?

Liquid silicone rubber (CAS 70131-67-8) is a polydimethylsiloxane-based elastomer that cures into a heat-, cold-, and weather-resistant rubber. It is used for molded seals, gaskets, and O-rings, for electrical insulation, encapsulation, and potting, for flexible casting molds, and for heat-resistant housewares and bakeware.

Is liquid rubber the same as silicone?

No. "Liquid rubber" is a general term covering several chemistries (including polyurethane and butyl-based products), whereas liquid silicone rubber specifically is a silicone (polydimethylsiloxane) elastomer. Silicone offers a wider service-temperature range and weather resistance than most non-silicone liquid rubbers.

What does liquid silicone rubber not stick to?

Cured silicone has low surface energy and generally does not bond to most plastics, metals, or other silicones without a primer, which is why it is widely used for release-type flexible molds. Adhesion to a specific substrate depends on the grade and any primer or surface treatment used.

Is liquid silicone rubber the same as a one-part RTV silicone?

They are related but distinct. Liquid silicone rubber is typically a two-component (Part A/Part B) platinum-cure system processed by injection or compression molding, while one-part RTV cures from atmospheric moisture. Confirm cure system and durometer per grade when ordering.

Does RawSource supply liquid silicone rubber in bulk?

RawSource distributes liquid silicone rubber in bulk industrial volumes for molding, electrical, and tooling applications. It classifies under HS code 3910.00. A Certificate of Analysis and Safety Data Sheet ship with each order; request both with a bulk quote.

Disclaimer. Information on this page — including properties, identifiers, hazard, transport (DOT/UN) and tariff (HS) classifications, and applications — is provided for general reference and is compiled from authoritative public sources (e.g. PubChem/ECHA, 49 CFR 172.101, the Harmonized Tariff Schedule). Values are typical and are not a guaranteed specification; the Certificate of Analysis (CoA) for the lot purchased governs. Products are sold for industrial and professional use only. Nothing here is a medical, health, or efficacy claim or advice. Always consult the current Safety Data Sheet (SDS) before handling, storage, transport or disposal, and confirm regulatory status, classification and suitability for your application and jurisdiction. Hazard, transport and tariff classifications must be verified for your specific shipment. RawSource makes no warranty, express or implied, and assumes no liability for use of this information. Trademarks. Third-party trademarks and brand names are the property of their respective owners; any reference is nominative — used only to identify a comparable product — and does not imply affiliation with, sponsorship by, or endorsement by the trademark owner.
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