If you are wondering exactly what is polyethylene, it is a thermoplastic commodity heavily used in consumer products (notably the plastic shopping bag). Over 60 million tons of the material is produced worldwide every year. According to news sources, this new composite has traces of “montmorillonite,” which is named for the Montmorillion settlement in France. These traces have been arduously inserted into polymer matrix as scientists developed a way to synthesize, which keeps the mineral structure intact, while simultaneously introducing it into a polymer with a totally different chemical nature. (A polymer refers to a large class of natural and synthetic materials with a variety of properties and purposes.)
Polyethylene is very sensitive to heating and it burns almost entirely. Its chemical nature has prevented its matrix from binding with mineral particles; that is, up until now. After thoroughly studying the structure of the new material, Russian chemists have developed the technique of using a mineral as a filling agent, which consists of numerous layers, none of which are bonded. They used a non-natural mineral that was only slightly modified (montmorillonite) and were the first to utilize the technique of ”very cold (meaning slow) neutron scattering.”
Researchers discovered that they could synthesize the material by varying parameters and mineral modifications. Introduction of as little as 1-3 volume percent of montmorillonite significantly reduced (compared to polyethylene) flammability and gas permeability of the new composite, as well as its thermal stability.
Since the catalytic agent is located both inside and outside mineral layers, polyethylene forms in both places. This multilayer “filling” becomes tightly bonded with the polyethylene matrix, resulting in a new composite material with evenly distributed nanolayers of montmorillonite (which, as any clay, doesn’t burn and doesn’t stretch under heating) in the total volume of polyethylene.
So the next time you bring a plastic bag home from the grocery, take another look. For one thing it may feel different to you and for another, it may be looking back!