Cambond is a Cambridge-based company that started life by developing an adhesive to replace toxic urea/formaldehyde (UF) resins for the wood panel industry. Its resin product is plant-based and derived from the by-products of whisky and bio-ethanol production called dried distillers grains and sol-utes (DDGS), which are non-toxic, food-grade materials.
Using this resin, the company can make commercial-grade plywoods, medium-density fibreboard and oriented strand board panels without the need for toxic adhesives. These panels have a much lower carbon footprint by replacing the UF adhesives, which are oil-based and energy-intensive to manufacture.
DDGS are a complex mix of proteins, oils and fats, and have two big advantages: they are readily available – more than a million tonnes a year are produced in the UK alone – and the chemical complexity and technical potential is engineered by nature. This means the chemical complexity can be used without the need for complex engineering, processing or chemistry, as is done with other bio-engineered materials.
Cambond has now pushed the original resin technology further. It discovered that it can be formulated with a range of polymers and plant fibres – such as peanut shells, straw, sugar bagasse and pineapple tops – to make different bioplastics. These materials are 50% plant-based and can be pelletised (the standard plastic format) using regular extrusion machinery.
The newest bioplastic product is called Camposite. It is able to replace standard plastics in existing machinery and manufacturing production lines for packaging, medical devices, cosmetics and other niche applications.
Cambond’s founder, Professor Xiaobin Zhao, used his contacts with industry and local government in China to establish a manufacturing base there in Jintan, near Changzhou. This has allowed Cambond to accelerate its development activities and carry out commercial trials with manufacturing partners in China, and the company now has sales in this sector.
Cambond believes this commercial experience has been useful in shaping its strategy and focusing its energy on practical and commercially viable technology. It now has a suite of patents protecting the technical and commercial potential of the resin discoveries.
In March, Cambond was named a regional winner in the Shell Springboard competition. The prize money of £40,000 has enabled it to accelerate plans to get a technical characterisation of Camposite completed and to begin pilot manufacturing trials in the UK.
The funding and business support it received through the Springboard programme will enable it to build a UK/EU base while continuing to expand in China. Unfortunately the company missed out on winning a further £110,000 funding in the Shell Springboard national finals held in May.
From a commercial viewpoint, Cambond will look to plug into existing supply chains by sourcing feedstock materials – polymers and DDGS – from various manufacturing and production processes. For example, it has used spent coffee grounds to make a reuseable coffee cup – the wasbeans cup – and used mixed disposable cups to make an MDF-style board. The commercial key to all this is to use existing systems and at a price acceptable to the market.
Camposite can be manufactured and supplied to manufacturers for less than the cost of their current virgin plastics because it is plant based (50%), and so enjoys the commercial advantage of coming from lower cost feedstock. Biomass by-products from agriculture are available all over the world in very large quantities for low prices.
But the company warns that its engagement with the manufacturing and sustainability universes has provided painful lessons. Industry will not pay a ‘green premium’ for environmentally friendly products, even though consumers might. Any new technology needs to work at an acceptable cost and in the existing infrastructure, while products need to be designed specifically for recycling.
Camposite can be formulated (for example with polypropylene) for recycling with existing systems or to be biodegradable (for example with polylactic acid). The company prefers to make it in a recyclable form because this is more in line with its aims to contribute to the circular economy.
To help solve the plastics problem, we need environmentally friendly plastic solutions that fit the model to cut oil and carbon usage, reuse by-products rather than discarding or burning them, and recycle using existing systems.
Theo Roberts is product development associate at Cambond