XPS analysis of Fabric Chars to determine the Phosphorous - Nitrogen synergism in Flame Retardants.
EMSL Project ID
12892
Abstract
Flame retardant finishing of Cellulosics fabrics are carried out using phosphorous based flame retardants. Theses flame retardants are known to act by condensed phase mechanism which accelerates the formation of char and inhibit the formation of volatile material. The phosphorous based flame retardants are mostly inorganic phosphates or organo- phosphorous compounds. They decompose to form mostly phosphoric acid or polyphosphoric acid at high temperature which chars the cellulose. Several studies have shown that the flame retardant efficiency of phosphorous flame retardants can be significantly improved if nitrogen is present in the flame retardant or is added as an additive. The role of nitrogen in improving the FR action is not very clear. Analysis of char of treated fabric is difficult as char is not soluble in any solvent. Analysis of char using XPS would definitely give some important information regarding the action of nitrogen or nitrogen containing compounds. It could be possible that phosphorous is forming new bonds with nitrogen during burning process which prevents its volatilization. Also presence of nitrogen may increase the retention of phosphorous in form of phosphoric acid at higher temperature. Presence of nitrogen and oxidation state of phosphorous and nitrogen on the char using XPS would give us idea about the mechanism of action of nitrogen which is not possible using any other instrument.
Project Details
Project type
Exploratory Research
Start Date
2005-02-10
End Date
2007-01-13
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members