235695

Octamethylcyclotetrasiloxane

98%

• Synonym(s): 2,2,4,4,6,6,8,8-Octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane, octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane
• Linear Formula: [-Si(CH₃)₂O-]₄
• CAS Number: 556-67-2
• Molecular Weight: 296.62
• Beilstein/REAXYS Number: 1787074
• EC Number: 209-136-7
• MDL number: MFCD00003269
• UNSPSC Code: 12352103
• PubChem Substance ID: 24853994
• NACRES: NA.23

Properties

• vapor density: 1 (vs air)
• Quality Level: 200
• assay: 98%
• form: liquid
• refractive index: n20/D 1.396 (lit.)
• bp: 175-176 °C (lit.)
• mp: 17-18 °C (lit.)
• density: 0.956 g/mL at 25 °C (lit.)
• SMILES string: C[Si]1(C)O[Si](C)(C)O[Si](C)(C)O[Si](C)(C)O1
• InChI: 1S/C8H24O4Si4/c1-13(2)9-14(3,4)11-16(7,8)12-15(5,6)10-13/h1-8H3
• InChI key: HMMGMWAXVFQUOA-UHFFFAOYSA-N

Description

General description

Octamethylcyclotetrasiloxane (D4) is a volatile methylsiloxane (VMS) with a relatively low molecular weight. This silicone fluid has a silicon-oxygen bond in a cyclic arrangement and methyl groups are attached to the silicon atom. D4 can be used in the manufacture of silicone based polymers for use in medical devices and personal care products.

Application

D4 can be polymerized through ring opening mechanism with a rare earth solid super acid as a catalyst for potential usage in the synthesis of vinyl coated polydimethylsiloxane (PDMS). It may also be used as a probe liquid for nuclear magnetic resonance cryoporometry (NMRC) to analyze the pore size distribution (PSD) of oil-bearing tight sandstone. Chemical vapor deposition (CVD) of D4 may be utilized for the preparation of siloxane based thin films.

Safety Information

• pictograms: GHS02,GHS08,GHS09
• signalword: Warning
• hcodes: H226,H361f,H410
• pcodes: P202 - P210 - P233 - P240 - P273 - P308 + P313
• Hazard Classifications: Aquatic Acute 1 - Aquatic Chronic 1 - Flam. Liq. 3 - Repr. 2
• Storage Class: 3 - Flammable liquids
• wgk_germany: WGK 3
• flash_point_f: 123.8 °F - closed cup
• flash_point_c: 51 °C - closed cup
• ppe: Eyeshields, Gloves, type ABEK (EN14387) respirator filter