In June, the European Chemicals Agency (ECHA) included the chemicals D4 (octamethylcyclotetrasiloxane
), D5 (decamethylcyclopentasiloxane) and D6 (dodecamethylcyclohexasiloxane) to the EU REACH Candidate List for Substances of Very High Concern (SVHC).
Methane supplied in gas cylinders, with purity better than 99.99% was used to deliver octamethylcyclotetrasiloxane
(D4) to the natural gas flow using custom-made pressure resistant gas bubblers.
The various endocrine disrupting chemicals are Parabens  UV-filters such as benzophenone-1, benzophenone-3 and octinoxate, [11-13] synthetic musks and other fragrance compounds, antimicrobials such as triclosan, cyclosiloxanes octamethylcyclotetrasiloxane
(D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6), bisphenol-A (BPA), alkylphenols such as nonylphenols and octylphenol, and glycol ethers.
Only few types of synthetic Si[O.sub.2] glass, obtained by sol--gel technology  or from silicon-organic raw-materials have Cl concentrations below 1 ppm (e.g., commercial types Suprasil UVL or Corning 7979, produced from octamethylcyclotetrasiloxane
A common approach to lower VOC content in solvent-based alkyd coatings is to use exempt solvents, such as acetone, methyl acetate, parachlorobenzotrifluoride (PCBTF), octamethylcyclotetrasiloxane
(D4 cyclic siloxane), and tert-butyl acetate.
The main cyclic VOSiCs present in biogases are the octamethylcyclotetrasiloxane
(D4), the decamethylcyclopentasiloxane (D5), the hexamethylcyclotrisiloxane (D3), and to a lesser extent the dodecamethylcyclohexasiloxane (D6).
Gleason, "Hotilament chemical vapor deposition of organosilicon thin films from hexamethylcyclotrisiloxane and octamethylcyclotetrasiloxane
, Journal of the Electrochemical Society, vol.
Andersen, "Modeling of human dermal absorption of octamethylcyclotetrasiloxane
(D4) and decamethylcyclopentasiloxane (D5)," Toxicological Sciences, vol.
Bis(3-aminopropyl)-tetramethyldisiloxane (BAPTM DS) and octamethylcyclotetrasiloxane
([D.sub.4]) were purchased from Gelest, Inc.
 used Tomlinson's model to study temperature dependence of friction on n-hexadecane and octamethylcyclotetrasiloxane
and in each case his results show inverse relationship.
We therefore used octamethylcyclotetrasiloxane
(OMS; Fluka), which has a boiling point of 448 K and a chemical shift of 0.094 ppm compared with TMS.