ERT believes that part of the solution to cracking the mixed plastics waste nut is Powder Impression Moulding technology. Roger Baynham, ERT executive deputy chairman, explains why
In order to meet increasingly demanding recycling targets, the recycling industry is having to devise and utilise new and inventive methods for dealing with plastic waste streams, particularly as they become more difficult to sort and separate. This was something Environmental Recycling Technologies (ERT) understood when it acquired the technology patent for the Powder Impression Moulding (PIM).
Invented and patented in Detroit, USA in the early 2000s by the automotive industry, PIM was used as a means of encapsulating structural components in polymers, in particular magnesium alloys, to produce complex one piece mouldings. Despite being taken up by US car manufacturing giants Chrysler and Ford, the crisis in the US automotive sector quickly rang the death knell for such R&D projects.
However, the expertise and knowledge gained in Detroit migrated to Brownwater Plastics in Kentucky, who successfully completed their own R&D programme to use the PIM process to produce even larger, more complex mouldings in the form of covers for Mississippi barges.
At the same time as this development was taking place in the US, it was recognised that the PIM process could utilise mixed, commingled or even unwashed and dirty plastics. Ultimately, by using the PIM technology, ERT saw a way of taking otherwise problematic mixed plastic waste and turn it into viable and valuable applications.
The focus on plastic waste and recycling has intensified in recent years as a result of producer responsibility regulation and legislation. The increased recycling targets in the waste packaging sector in the UK announced in 2012, as well as targets soon to be crystallised in the WEEE and ELV sectors, will mean that MRFs and plastic recyclers will have to adapt to ever more mixed and contaminated waste streams. Furthermore, the erection of the ‘Green Fence’ by Chinese customs in early 2013, has also shown how important it is for other countries to find sustainable markets for products made from plastic waste.
ERT believe that in the future, PIM is uniquely positioned to act in synergy with conventional plastic recycling to drive plastic waste up the waste hierarchy from landfill and recovery.
We have identified three key areas of focus as raw material for the PIM process and as opportunities for our future licensees. These are: rigid plastic packaging (pots, tubs and trays); flexible plastic packaging (films); and WEEE and ELV plastic waste.
While there are a limitless number of potential applications that can be made from the PIM process, as diverse as acoustic barriers, pallets and stadium seats, several of our licensees have focused on applications which provide opportunity for using substantial volume of plastic waste, such as in the plywood replacement sectors.
The plywood industry in the UK alone is estimated to be a staggering 30 million sheets per year. As a result of the project work led by ERT, our licensee 2K Manufacturing has developed a branded multi award-winning PIM plywood substitute known as Ecosheet, which uses PIM technology and plastic waste. 2K’s Ecosheet has been so successful, that its order book extends nearly six months in advance.
Contour Showers, another of our licensees, is successfully using the PIM process to manufacture its range of Ecodec shower trays from mixed waste plastic, which are an outflow from the sorting and recycling of WEEE plastics. It is a great illustration of how technology, in this case PIM, can be adapted to produce high performance niche products from recycled material.
Such opportunities are proving fruitful as we are currently working with prospective licensees in Europe, China and South America.
Ultimately, ERT believes that its knowledge and experience will provide the traction to export its innovative PIM technology globally.
The Powder Impression Moulding (PIM) process
PIM is essentially a composite moulding technology where the key features are a solid skin material encapsulating a foamed core. The key benefits of this are that it combines light weight with rigidity.
One of the features of the PIM moulding process is that it does not rely on the movement of molten polymer in the moulding process as one would find in all traditional plastic moulding techniques, such as injection moulding, extrusion and rotational moulding. Instead the PIM process relies on sintering of particles under heat. The bonding which occurs as a result means that PIM can accommodate a variety of different and mixed polymers.
The process requires the polymer to be reduced to a powder. The core material is a blend of pulverised polymer and chemical foaming agent.
Two open moulds are preheated and the skin material is applied to both moulds to sinter in preparation of the subsequent application of the core material. The moulds are then closed and heat is reapplied. During this process the foaming agent is activated and subsequently the moulds are cooled, opened and the product removed.
Brownwater Plastics case study
Brownwater Plastics, an affiliated company to James Marine, a leading US inland river vessel repair company, holds an exclusive license from ERT to manufacture and sell barge covers and other marine products in the USA made using the PIM process.
ERT believes that the barge covers being produced by Brownwater Plastics are potentially the world’s largest thermoplastic mouldings. The barge covers are fully scalable, as 20ft x 10ft sections are hot welded together to create barge covers as big as required.
The covers are used on barges that transport goods such as grains, fertilisers and industrial steel. The unique covers have entered a market that has historically been dominated by a fibreglass product. However, these PIM produced covers are a superior product due to a number of factors, including buoyancy and the fact they can be recycled at the end of their lifecycle.
Commenting on the barge covers and the PIM technology, Jeff James, chief executive at James Marine, said: “Whilst our PIM manufactured barge covers are superior to those already on the market in a number of ways, we have also seen companies attracted to them due to their green credentials.”
North Brook Farms case study
North Brook Farms, a diversified manufacturing company with product offerings in the agricultural, equine, commercial/industrial and consumer markets, holds a non-exclusive licence from ERT to manufacture and sell a range of flat sheet products within the USA, Mexico and Canada.
Using PIM, North Brook Farms is in the process of setting up to manufacture a plywood substitute to replace plywood for various applications within the agricultural, marine and construction markets. Having tested the market by purchasing a container of Ecosheet from 2K Manufacturing, North Brook Farms found that it has many characteristics which make it an excellent product for these industries, including: 0% water absorption, being able to withstand repeated high-pressure washing, excellent chemical and abrasion resistance, use in areas where traditional materials rot or splinter, being strong and durable so suitable for stud wall lining and general woodworking projects.
With a philosophy focused on utilising recycled materials, North Brook Farms saw the natural synergies between its own business and what ERT and PIM had to offer. North Brook Farms’ main operations are located in Auburn, NY in the Finger Lakes region.