Jonathan Marks Fernando Robelo Durable Flame Retardant for Cellulosic Fabric
Summary Introduction Background Experimental Results and Discussion Conclusion Further Research
Introduction Cellulosic fiber Important biopolymer Available in vast quantities Good mechanical properties Good biodegradability Good hydrophilicity Disadvantages Ease of thermal degradation, ignition and burning Increases risk of injury or property damage dex.php?pgid=index
Background Flame retardants Chemicals added to polymers to prevent combustion and delay the spread of fire Based on halogen, nitrogen and organic-phosphorus compounds Involves the use of formaldehyde during manufacturing or application Novel halogen- and formaldehyde-free flame retardant (Neo-FR) Halogen based FRs have potentially toxic effects Formaldehyde is a known carcinogen
Synthesis of Neo-FR Step 1 Solution of phosphonitrilic chloride trimer in tetrahydrofuran was added to a solution of triethylamine and acrylamide Product was filtered to remove triethylammonium chloride THF was removed using a rotary evaporator Step 2 Branched polyethyleneimine solution was applied onto cotton fabric followed by Neo-FR compound solution
Synthesis of Neo-FR 978
Experiment Neo-FR tested against commercially available flame retardant agent (Pyrovatex CP New) Tests Chemical structure characterized by Fourier-transform infrared spectroscopy (FTIR) Surface morphology and fiber char residue observed through scanning electron microscope (SEM) Thermal property examined by thermal gravimetric analysis (TGA) FR performance before and after laundering evaluated by limiting oxygen index (LOI) and vertical flammability tests Tensile strength of untreated and treated fabric measured
Results and Discussion
Analysis of FTIR Spectra NH2 : 3357 and 1596 cm -1 P=N : 1313 and 1224 cm -1 P-N : 874 cm -1 P-Cl : 599cm -1 As the reaction occurs, peak at 1250 cm -1 strengthens and at 599 cm -1 disappears
Surface Morphology Figure A&B: Surface of cotton fibres Figure C&D: Surface of cotton fibres after burning
Thermal Properties of Cotton Fabric Result clearly shows the high flame retardant property of the Neo- FR finishing
Limiting Oxygen Index vs. Weight Gain
Vertical Flammability Test SamplesLaundering cycles After flame time(s) After glow time(s) Char length (mm) Neo-FR treated fabric Pyrovatex CP new treated fabric
Tensile Strength of untreated and FR treated fabrics ItemTensile strength (N) in weft direction Tensile strength (N) in warp direction Elongation at break (%) in weft direction Elongation at break (%) in warp direction Control Neo-FR treated fabric Pyrovatex CP new treated fabric
Conclusions A halogen-free and formaldehyde-free flame retardant was synthesized and applied to cellulosic fabrics LOI and Vertical Flammability test indicate that the flame retardant has excellent flame retardant properties and durability for cellulosic fabrics by a low temperature finishing process Could be well used as a durable flame retardant system for cellulosic material
Further Research Given the properties of the product, it may be implemented in products already Since the ban of the brominated fire retardants in 2006, research has been implemented Ever since, phosphorus based fire retardants have started to become popular
Questions?
Zongyue Yang, Xiaowen Wang, Dapeng Lei, Bin Fei, John H. Xin, A durable flame retardant for cellulosic fabrics, Polymer Degradation and Stability, Volume 97, Issue 11, November 2012, Pages , ISSN , /j.polymdegradstab ( ezproxy.tamu.edu:2048/science/article/pii/S ) ezproxy.tamu.edu:2048/science/article/pii/S Ike van der Veen, Jacob de Boer, Phosphorus flame retardants: Properties, production, environmental occurrence, toxicity and analysis, Chemosphere, Volume 88, Issue 10, August 2012, Pages , ISSN , /j.chemosphere ( ezproxy.tamu.edu:2048/science/article/pii/S ) ezproxy.tamu.edu:2048/science/article/pii/S K. Kalachova, P. Hradkova, D. Lankova, J. Hajslova, J. Pulkrabova, Occurrence of brominated flame retardants in household and car dust from the Czech Republic, Science of The Total Environment, Volume 441, 15 December 2012, Pages , ISSN , /j.scitotenv ( References