SAA/BASA meeting 3rd December 2015, Green Issues and REACh, Sustainability and Challenges in Adhesives and Adhesion, Held at the Society of the Chemical Industry, 15, Belgrave Square, London.
This was another interesting meeting raising important issues and was well attended.
Paper 1. The first paper entitled ”Green Issues in Adhesion” was given by James Clark from York University. He explained that York University now has a Green Chemistry Department.
Other Universities around the world are setting up similar departments as more countries also begin to take these issues seriously. He said we are using non-renewable diminishing resources while using dangerous processes and yet these often produce more waste than product. It has been a concern of mine for some ten years or more that population is continuing to rise while the means for providing food and other essentials are being reduced. This also suggests that vast amounts of material are wasted making cheap and nasty products with a short service life when higher quality materials could produce much longer lives and save the energy wasted due to making short life products. He discussed the manufacture of bio-adhesives from waste bio-mass and the conversion of bio-silicates to bio-boards for flooring. James also said that the number of environmental laws has increased by 140 times since 1900. Green Chemistry is taking off at a phenomenal rate in the North America, Western Europe and Asia Pacific regions and to a lesser extent worldwide. So much can be re-used that maybe we should rename our Waste or Rubbish tips as “Re-usable material collection centres”!
His full paper is in colour and well worth reading. He can be contacted at or
Paper 2.The second paper was given by Lorna Williams, Secretary of BASA entitled,“The Industrial Impacts of REACh (Registration, Evaluation, Authorisation and Restriction of Chemicals”.
She said this was a very demanding system for any business, either large or small. So far most experience has been built up by larger companies because they use or supply larger volumes of chemicals, and registration whilst expensive can be justified. A problem is almost certain to arise with smaller companies supplying lower volumes when cost could make registration a serious problem or even cause manufacture to cease. She also said that 96% of all companies in Europe were SME’s. Another problem could be trying to find suitable alternatives if some chemicals are banned. She explained that some chemicals regarded as “safe” were being re-assessed.
Paper 3, “Green Issues and REACh; An Epoxy Perspective-Opportunities and Risks was given by Stuart Darwen from CTP GmbH (A part of the Aditya Birla Group) Stahlstrasse 60,65428 Ruesselsheim, Germany.
Stuart said that the implementation of REACh anda growing awareness of Green Issues have led to significant changes in the materials and technologies that can be used in the epoxy resin and curing agent industry. This change has presented both opportunities and risksin the use and development of epoxy systems. He discussed some of these. Formulations have to be quite precise as they are adjusted to give the properties required. It could require considerable testing if a curing agent was banned and another had to be found while trying to meet an existing specification. He pointed out that epoxies were used in Adhesives, coatings, composites, construction and electrical circuit boards. These required formulations to suit the needs of each end usage. He said the MSDS needs to be simpler but more comprehensive. Workers need to know safety needs and correct mix ratios. Some new symbols may need explaining. Stuart also said that medical advice was not always given effectively to the market.
Paper 4 “Strategies for Dismantleable Adhesion to Permit re-use andRecycling”. This was given by Constantine Marlasof Loughborough University. E-mail
Constantine mentioned a number of applications where dismantling would be helpful to re-cycling.
Non –structural items were discussed first.
These were Signage, Automobile trim and trunking.
Construction Industry items were
Industrial flooring
Plaster boards
Bonding of concrete
Reinforcing concrete
Aerospace items
Racing car bodies are also carbon –fibre composites
Aircraft floors
Flaps, Spoilers, Fairings, Helicopter blades, Missile parts.
Many parts of unmanned aircraft.
Resins are also used to repair composite aircraft parts.
The use of dis-mantleable adhesion to allow for sustainable use of materials, by enabling: flexible manufacturing; ease of repair, and: eventual re-use of bonded structures was reviewed by Constantine Marlas (Loughborough University. Mr. Marlas first discussed the previously-reported procedures for the attainment of dis-mantleable adhesion by the use of: ROMP chemistry; elect-release adhesives; chemical foaming agents, and, thermally expanding microspheres. He then proceeded to discuss the developments in this field made at Loughborough University. Mr Marlas showed the effectiveness of using both de-compostable interfaces via the reversible hydrolysis of Si-O-Si bonds, and the use of microwaves combined with thermally –expanding graphite. Another highly successful approach was the development of a conducting epoxy adhesive which experienced a large resistive heating effect when a current was applied. In creep tests, metal-metal joints were disbonded within a few seconds of the current being applied with a low static load of 200N.
Paper 5 “Modification of the Tartaric/Sulphuric Acid anodising process TSA for anti-corrosion and adhesion performance”, was given by M.Curioni from the Corrosion Protection Centre, School of Materials, Manchester University.
This process has been studied in depth to enable it to replace the older and very effective Chromic Acid Process. Chromic Acid is hazardous and is no longer regarded as acceptable on health grounds. Michele explained that Tartaric sulphuric acid is now one of the most popular treatments to replace CAA. TSA treatment involves the immersion of the part in a bath containing dilute sulphuric acid and tartaric acid, followed by the application of an initial voltage ramp up to 14V, followed by constant voltage anodising at 14V. The resulting oxide morphology is relatively close in the outer regions and more opened in the inner regions of the film. He said that in the present work, a modification of the traditional TSA cycle is proposed, based on the detailed characterisation of the oxidation behaviour of the alloy. In particular, the relationship between the potential applied during anodising and the pore morphology is evaluated, together with the effect of the anodizing potential on the intermetallic particles. Based on the results, a modified cycle is proposed, where large pores are generated in the outer film regions to improve adhesion and finer pores are generated in the inner regions to enhance corrosion resistance.This process seems to have achieved its aim to continue anodising aluminium alloys successfully.
Paper 6. Evaluation of REACh Compliant Organic coatings.This was given by Dr Dave Sidgwick from GE Aviation Systems Materials Engineering, Bishops Cleeve, Cheltenham, GL52-8SF, UK. E-mail
Dave explained that this was a wide ranging study by the HITEA Consortium. He said that while generally positive results were found for hexavalent chromium free primer systems on anodised surfaces, those same paint systems struggled to reproduce such results on Chemically Converted Coating (CCC) prepared surfaces. He concluded that Conversion coated and primed samples generally gave poor results for corrosion. No viable replacement was identified. His paper can be e-mailed on request.
Paper 7. Spraying without overspray: reducing waste, improving safety. This was given by Guy Newcomb, CEO of Archipelago Technology Group Ltd.
Email:
His paper demonstrated some interesting new thinking on the subject of large area painting. Guy said that the normal methods wasted a considerable amount of paint and caused atmospheric pollution in the process. Anyone who has used only a small spray can is likely to agree with this. His new method uses small drops of paint deposited at high speed and gives a finish equal to that of a good spray system while causing almost zero pollution and waste. The system is called “Power drop” and ejects viscous materials. Equipment can be designed to cover quite large areas. Please contact Guy for further information. His e-mail address is