The next time you paint your living room you could be doing more than simply brightening up the space – how about actually cleaning the air in the room.
Chemical and biochemical engineering professor Paul Charpentier, who recently received $30,000 from the Western Innovation Fund, is examining how plastic coatings based on polyurethanes can be used for a new generation of self-cleaning, anti-microbial polymer films on various surfaces.
With his research, nanostructured titanium dioxide of a controlled crystal structure is linked directly to polymer chains during formation so nanoparticles cannot be released during use. The coatings will be examined for several applications in the anti-graffiti, food processing and home product industries.
“This project on self-cleaning polymers is targeted at several polymers that we come across in our everyday lives including polyurethanes and polyesters,” says Charpentier. Polyurethanes are often used in outdoor and automotive paints, coatings on flooring such as ceramic tiles and hardwood floors, while polyesters are often spun into yarns for use in clothes, home furnishings and window coverings.
“The idea is to be able to make these polymers ‘clean themselves’ from dirt, and kill any micro-organisms that attach to their surfaces, such as E-Coli or Listeria, without affecting the other polymer properties'” he says.
Charpentier adds the polymers can also potentially clean the surrounding air when integrated into window coverings or wall paints. The polymers for these applications are made in a polymerization process called step-growth or polycondensation from monomers – the basic building blocks that form the polymers.
Nano titania (TiO2), which has been used in polymers for decades in urethane paints, PVC vinyl siding on houses and even sunscreen, has what is called a rutile crystal phase that blocks UV radiation from the sun and protect the polymer or, in the case of sunblock, our skin.
However, in the anatase phase, TiO2 is used as a photo-catalyst that can kill micro-organisms, which is used by local companies such as Trojan Technologies and Purifics for water purification.
“By using a blend of these crystal forms, we can optimize both the UV-protection and self-cleaning, anti-bacterial aspects,” says Charpentier, adding when TiO2 becomes nanosized it has additional advantages of becoming transparent in a polymer, although a fundamental scientific challenge is on how to keep the nanocrystals from bunching together.
As particles become smaller and smaller, their surface areas become higher and the forces to aggregate become higher. Hence, if you just add in nano TiO2 to a polymer, it will agglomerate and won’t work very well.
“Our trick is to co-ordinate blends of nano TiO2 to these monomer building blocks to form modified monomers, that can subsequently be polymerized to form the polymer nanocomposites,” Charpentier says. “This helps to separate the nanocrystals proving enhanced performance.”
He has been getting significant interest from several companies representing the food processing, anti-graffiti, solar and window coating industries. Charpentier is working with these companies on different commercialization strategies through Western’s WORLDiscoveries, the business development arm of London’s extensive research network and the bridge between local invention and global industry.
For example, in the food processing and anti-graffiti industries, Charpentier is working with a company that is a trained applicator of polyurethane coatings by spraying. He is also working with an Ontario window coatings manufacturer so the technology fits into their conventional weaving and lamination processes.
Another area aggressively being targeted is the solar materials market that is rapidly growing in Ontario, where Charpentier’s research can play a role in solar thermal, photovoltaics and greenhouse polymer films that are transitioning to next generation plastics.
In addition to Charpentier, computer science professor Mike Katchabaw also received an award ($24,000) from the Western Innovation Fund.
His Algorithmic Music Evolution Engine (AMEE) is a software system capable of dynamically composing and emotionally adapting music in real-time for a variety of new media sectors, including gaming, mobility and soundtrack composition. Research to date has created a core engine that can be embedded and used in other applications, resulting in multiple publications, a patent application and considerable commercial interest.
This Western Innovation Fund-supported project will focus on the mobile sector, moving the AMEE system on to cutting-edge smart phones and enabling new gaming and music applications, including a novel ring tone generator that composes ring tones customized based on emotions.