Last month, this blog received a valuable comment from Jerry Turner of Vitro Minerals. He reminded readers that glass is one of those materials that is ideally suited to recycling over and over again. With glass powders now being used in industrial primers, roof coatings and various sealants, he points out that recycled glass gives coating formulators another tool to increase their sustainability.

Jerry’s comment prompts me to come back to recycling as a key issue. It’s a tough one because it represents an activity that lies outside the immediate control of both raw materials and coatings manufacturers.

To address this element of the coatings life cycle, some tough questions need to be addressed. What happens to a coated product or a coating when its prime application has been completed and it is no longer needed and must be disposed of? Is that the end of the line? We talk about ‘cradle to grave’, but can the ‘grave’ in the form of incineration and landfill be avoided? In order to be good managers of the world’s resources, a positive response to this question HAS to be found, and the way forward has to come either in the form of reduced consumption or recycling. Vitro Minerals may well have a handle on part of the answer. 

Ellen Macarthur is best known as a solo long-distance yachtswoman who gained international renown by breaking the world record for the fastest solo circumnavigation of the globe in 2005. She is also a truly inspiring environmental leader who, on retirement from sailing, launched the Ellen MacArthur Foundation; a charity focusing on accelerating the transition to a regenerative circular economy. The Foundation works in three areas:

• Education: inspiring a generation to re-think the future;
• Business: catalysing business innovation;
• Insight: the opportunity for a re-design revolution.

The starting point for me in understanding her prime message is the circular economy model which is described in the web address below:

http://www.ellenmacarthurfoundation.org/circular-economy/circular-economy/interactive-system-diagram

The model calls for life cycles of all products to be designed in ways that restore materials for reuse either through technical or biological routes. Whenever we see companies or coatings trade associations organising paint recovery and recycle systems, as the ACA is currently doing in some States of the Union, they are exemplifying one aspect of the technical recycle route. The Vitro Minerals proposal is another example that follows the technical recycle route. When agricultural waste is synthetically decomposed into its organic chemical building blocks and reconstituted to make resins or solvents for paint manufacture, then that is an example of the biological cycle at work. The key premise is to minimise incineration and landfill. One thing for sure, it would take some very novel thinking and technology to eradicate incineration and landfill completely, but that is exactly what the world needs!

Every now and then, I see something in the trade press that demonstrates that R&D is being applied by both academics and commercial corporations to develop new technology in line with this thinking. For example, could it be possible to manufacture resins directly from agricultural waste? Photosynthesis is nature’s way of recycling carbon dioxide back into products valuable to both nature and society. Can new chemistry copy nature to capture carbon dioxide from decomposing agricultural waste and successfully manufacture materials that the coatings industry can use? Could carbon dioxide generated from paint at the end of its life be transformed into raw materials for new coatings formulations? Once just a dream, there are signs of it becoming a reality.

In an exciting development, academics from Eindhoven University of Technology, Holland and Imperial College, London, UK, have recently reported discoveries of innovative catalyst systems that make possible the polymerisation of resins incorporating carbon dioxide without the help of enzymes. Some of the resins produced by these mechanisms ‘are promising as binders in industrial paint formulations’.

Novomer, a U.S. sustainable materials company pioneering a family of high-performance polymers and other chemicals from renewable raw materials, has produced its first large-scale manufacturing run of polypropylene carbonate (PPC) using carbon dioxide as a feedstock at a manufacturing plant of speciality chemicals firm Albemarle in the United States. This type of resin is said to be comparable in properties to polycarbonate but avoids the use of phosgene and bisphenol A as precursors.  Life cycle analyses have demonstrated the environmental effectiveness of this technology.

Now I learn that researchers at Brown University have announced a breakthrough in making acrylates using ethylene and carbon dioxide (CO₂), with nickel as a promoter.  Usually, acrylates are made by heating propylene; a process that can be relatively expensive when produced on the mass scale needed for global acrylate demand.

 Technical innovation is an essential step on the path not only to the enhancement of the sustainability of coatings products from cradle to grave, but also to the avoidance of waste.