New process leads to highly versatile polymer latex for self healing paints, clever packaging

26-Nov-08

Research chemists at UK's University of Warwick have developed a unique process to cover small particles of polymer with a layer of silica-based nanoparticles. The research, led by Dr Stefan Bon of University of Warwick's Department of Chemistry, has created a "soap free emulsion polymerization process" which makes colloid particles of polymer dispersed in water and in one simple step introduces nanometre sized silica based particles to the mix. These silica based nanoparticles (about 25 nanometre in size) then coats the polymer colloids with a layer. The new process results in a highly versatile polymer latex product which used to create scratch resistant self healing paints and also can be tailored to produce polymer based packaging which will allow water or air to pass through the packaging in tailored ways. The resultant rough textured spherical shapes also lend themselves to the creation of sheets with polymer that present much more surface area than usual allowing more efficient interaction with other materials. Further, the material was exposed to a second simple step which deposited another polymer layer on top of the already silica based nanoparticles "battered" polymers. By this, the researchers were able to produce particles with an even greater range of properties and uses. As opposed to other processes, Warwick research team's new process reduces extensively the time needed to create such versatile materials and its single step can already be produced on a mass scale with currently used industrial equipment. The team has demonstrated that the useful product can easily be made up to around 45% of the volume of each water-based solution used in their process compared to 1 - 10 % for comparable multi-step processes that make these complex particles.