Microwave assisted preparation of flame resistant cotton using economic inorganic materials

Authors: Chang, Sechin; Condon, Brian; Smith, Jade

Submitted to: FIBERS
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/3/2018
Publication Date: 11/6/2018
Citation: Chang, S., Condon, B.D., Smith, J.N. 2018. Microwave assisted preparation of flame resistant cotton using economic inorganic materials. FIBERS. 6(4):85-95. https://doi.org/10.3390/fib6040085.
DOI: https://doi.org/10.3390/fib6040085

Interpretive Summary: In this work, economic inorganic flame retardant finishing treatments based on urea and diammonium phosphate have been applied to cotton fabrics using microwave-assisted technology. All the urea/DAP treated fabrics showed a significant resistance to flame application during flammabilities. We have developed an efficient method, which has the advantages of shorter reaction time, simple procedure, and no environmental pollution compared to the conventional method. Our results reveal that most of the flame retardant treated fabrics showed better anti-flammable activity than the control fabric.

Technical Abstract: Innovative approaches for preparing flame retardant cotton fabrics were employed by utilizing a microwave-assisted technique with a minimum amount of co-solvent. Our attempts at flame retardant cotton fabrics treated with low cost inorganic formulations, such as urea and diammonium phosphate, were done successfully. The evidence of flame retardant chemical penetrations or surface modification of cotton fabrics was confirmed by scanning electron microscope (SEM), and the treated cotton fabrics were evaluated by flammability tests, such as 45°angle (clothing textiles test), vertical flame(clothing textile test) and limiting oxygen index (LOI). For formulations with urea only, LOI values of treated fabrics were 21.0-22.0% when add-on values for the formulation were 5.16-18.22%. For formulations comprising urea with diammonium phosphate, LOI values were greater than 29.0% when add-on values for the formulation were 1.85-7.73%. With the formulation comprising urea with diammonium phosphate, all treated fabrics passed the vertical flame test when add-on values were 5.34-7.73%. In all cases, char lengths of fabrics that passed the vertical flame test were less than 50% of original length and after-flame times were 0-3 seconds and after-glow times were less than 3.2 seconds. Additional thermal properties of desired products will be discussed using thermogravimetric analysis (TGA) and microscale combustion calorimeter (MCC).