By Cameron Chai
Materials scientists from the University of Maryland (UMD) and the National Institute of Standards and Technology (NIST) have demonstrated that a nanocomposite material provides more fire protection when the extensively and evenly dispersed nanoscale clay plates of clay are in a polymer.
In tests conducted on five specimens with varying dispersions of clay plates, but with equal amount of nanoscale filler, the sample that had the widest dispersion was more resistant to burning, igniting and degradation.
The NIST-UMD scientists used a polymer normally used in insulation and packaging products and also in cutlery and other products filled with montmorillonite nanometer scale plates. Montmorillonite is a kind of clay having a sandwich-type molecular arrangement. The montmorillonite clay was filled in the polymer, and the combination lead to a superior material. The team subjected the specimens to a number of flammability tests and characterization methods. The tests provided a comprehensive picture of the dispersion of nanoscale clay plates and the response of the material to heat influx. Studies suggested that the dispersion, stacking or clumping of clay plates in polymers impact the characteristics of the resultant material.
When nanoscale plates of clay were better dispersed they got entangled more easily when subjected to heat. They formed a network structure with fewer gaps and had a lesser likelihood of getting cracked.. The resultant structure was a heat shield that had the ability to reduce flammability and the rate of degradation.
Scientists are now exploring other avenues of reducing flammability by using novel techniques and advanced materials.