Search results
Results from the WOW.Com Content Network
The generalised chemical structure of polyisocyanurate showing the isocyanurate group. The polyols are abbreviated as R-groups.. Polyisocyanurate (/ ˌ p ɒ l ɪ ˌ aɪ s oʊ s aɪ ˈ æ nj ʊər eɪ t /), also referred to as PIR, polyol, or ISO, is a thermoset plastic [1] typically produced as a foam and used as rigid thermal insulation.
Despite this low acute toxicity, an extremely low short-term exposure limit (STEL) of 0.07 mg/m 3 is the legal limit for all isocyanates (except methyl isocyanate: 0.02 mg/m 3) in the United Kingdom. [22]
As each phenol group contains only a single t-butyl group they are considered to have low steric hindrance and thus high activity. Arranging three of these around an isocyanurate core gives a compound with a sufficiently high boiling point that it is not volatilised out of the plastic during plastic extrusion and moulding (up to 320 °C in the case of PA).
Methyl isocyanate (MIC) is an organic compound with the molecular formula CH 3 NCO. Synonyms are isocyanatomethane and methyl carbylamine.Methyl isocyanate is an intermediate chemical in the production of carbamate pesticides and Haffmann Bromamide Degradation (such as carbaryl, carbofuran, methomyl, and aldicarb).
Sodium dichloroisocyanurate (INN: sodium troclosene, troclosenum natricum or NaDCC or SDIC) is a chemical compound widely used as a cleansing agent and disinfectant. [1] It is a colorless, water-soluble solid, produced as a result of reaction of cyanuric acid with chlorine.
[5] [6] Although more viscous in these forms, it reduces the volatility and toxicity. At least 3 companies sell material in this form commercially. It is also used as an activator in process of in situ polymerization of caprolactam i.e. cast nylon process.
Meanwhile, Los Angeles Fire Department Chief Kristin Crowley said residents eager to return to evacuated areas must remain patient.
Methylene diphenyl diisocyanate (MDI) is an aromatic diisocyanate.Three isomers are common, varying by the positions of the isocyanate groups around the rings: 2,2′-MDI, 2,4′-MDI, and 4,4′-MDI.