Polymer solution to a sticky problem

A Welsh company has developed a new chemical base for chewing gum that allows it to be removed from pavements and other surfaces with a mild soap solution or simply washing with water.

‘We have managed to change the surface characteristics of the gum base which will allow a stream of water or a mild soap solution to break the adhesion between chewing gum residues and surfaces such as paving stones, furniture, hair and so on,’ said Professor Terence Cosgrove, chief scientific officer of start-up company Revolymer.

Revolymer develops new polymers from existing commodity polymers that potentially have applications in medical devices, paints and coatings, textiles and personal care products.

In UK Government studies, chewing gum pollution has been considered as one of the key issues facing local authorities and a chewing gum tax is being considered in the UK, Ireland and other EU countries. As an example of the problem, Westminster city council spends some £95,000 per year removing gum from pavements.

Historically chewing gum was made from Chicle which is a polyterpene and is made up of 15 per cent rubber and 38 per cent resin. Modern gums are made from synthetic latex to which softeners, sweeteners and flavourings are added. Synthetic rubbers are stretchy, retain their properties indefinitely under all weather conditions, are resistant to aggressive chemicals and have strong adhesive properties.

A change in the stickiness or the biodegradability of chewing gum would require a change in the chemical structure of the rubber gum base. However, the gum base also determines commercially important features of chewing gum such as flavour retention, ‘chewiness’ and shelf life. The challenge is to develop a non-sticky or biodegradable gum base that does not compromise commercially critical features.

Recent developments within the laboratory indicates Revolymer can now almost ‘dial in’ the stickiness required from high to very low contact adhesion.

IPGroup and SULIS, British venture capital firms that specialise in commercialising technologies developed within universities, funded Revolymer, which was set up with the support of the Welsh Assembly Government.