The desire to rid our streets of discarded chewing gum drove Professor Terence Cosgrove in the Department of Chemistry to find a way of preventing gum from sticking to the pavement. Not only will his solution save millions of pounds in cleaning costs for councils around the country, but it has also opened up surprising opportunities for Cosgrove and his team at Revolymer.
Terence Cosgrove has been working on polymers and their interactions with surfaces for 20 years. Around ten years ago, he was approached by a technology transfer manager looking for a way to remove chewing gum from pavements in order to save councils millions of pounds a year in street cleaning. Nothing came of those discussions, but that led Cosgrove to consider the problem further and five years ago he set up an undergraduate project to investigate it.
The research discovered a polymer that was similar to the polymers used originally in chewing gum (natural rubber). By using a technique called chemical grafting, the polymer was transformed from a hydrophobic material that hates water to a polymeric surfactant that loves it. This enabled the design of a gum that could be easily re-moved from a range of materials including fabrics, carpets and paving stones. -We found we could easily remove the polymer from different materials but at this stage it was made with toluene, so you wouldn‘t want to put it in your mouth, commented Cosgrove Revolymer was created when Cosgrove was introduced to Roger Pettman, a serial entrepreneur with a PhD in organic chemistry. Having created a business plan, the new team entered and won the University‘s Enterprise Competition, which led to an initial investment of £750,000 by the IP Group and SULIS, a seed corn investment fund. Over the following year the team, including PhD student Voss Gibson and Dr Erol Hasan, worked out how to make chewing gum. At the same time, they developed a version of the polymer that was safe to use in food and cost-effective for the chewing gum market.
The company filed a series of patents and started making gum in small quantities at the University, initially coming up with over 200 different proto-type recipes. We carried out parallel experiments with commercial gum, said Cosgrove. The first ones broke up in the mouth but by optimising the formulations we overcame that, while still maintaining the gum‘s disintegration properties. Product development focused on improving the chew, enhancing the initial flavour release, reducing the adhesion and developing a longer-lasting flavour. At the end of these tests, they had whittled down the gum candidates to four or five variants. It was during this time that the company began to grow and through a strategic alliance with Warwick International, a manufacturer of bleach additives, Revolymer established a research laboratory in Mostyn, North Wales. The agreement was that Warwick would use Revolymer‘s polymer coating technology and also manufacture Revolymer‘s polymers. A second round of funding provided a further £2 million of investment, plus government grants, which allowed the development of a proto-type, but the difficult job of proving the effectiveness of the technology was still ahead. This led to the Big Chew‘ event that took place during Easter 2008.
The ‘Big Chew' took place during Easter 2008. Fifty volunteers from the University and Revolymer chewed their way through 200 samples of gum; some were a commercial brand of gum, some were the Revolymer gum with the polymer additive, and some, acting as control samples, were the Revolymer gum without the polymer. Part of the experiment was to find out how much of the polymer was needed to create the desired effect, so the gum was stuck to the walkway at the Chemistry Department for a month to see what happened. The results were very exciting. All the gum with our new polymer was easy to remove and this allowed us to choose the best formulation, said Cosgrove. Our gum degrades in water and we have subsequently found in real street trials that three out of four cuds will disappear spontaneously with ordinary street cleaning, rain and pedestrian traffic, and the rest should disintegrate with time.
The company is now in the process of licensing the technology. You can incorporate the polymer into the gum in various ways, which results in a range of effects, explained Cosgrove. The properties vary depending on how cold and wet the environment is, and so you need more additive in a hot, dry country. But we have now established the optimum formulation for use around the world. The benefits of the new polymers are not confined to gum on pavements: With the additive it is easy to remove gum from carpets and shoes as well, although it comes off plastic soles more easily than leather ones. We went into the office of the executive of a major investor and stuck gum on his carpet. As we expected, it came off easily, but it was an exciting moment, he joked.
In May 2008, Revolymer raised a further £10 million towards its goal of commercialising the technology. It is now making the polymer in commercial quantities with a team of 30 people and is selling it to gum manufacturers directly. Food approval is expected in the USA in late 2008 and in the EU in 2009. The polymer technology that has been developed also opens up other markets, including personal care and household products, and drug delivery. With a family of new polymer systems to exploit, Revolymer is much more than just a lifesaver for the gum manufacturers. ˇ
Text courtesy of re:search 2008