Clearview National May 2018 - Issue 198 - Page 52

PROUD SPONSOR OF DOORS & WINDOWS DOORS&WINDOWS Legacy planning for ‘perfect’ PVC-U » » HOW SYSTEMS COMPANIES manage legacy chemicals in recycled content is key if they want to be able to guarantee through-life performance. To step into PVC-U recycling is something of a step into the unknown. The lead stabilisers and additives may be long since gone from PVC-U extrusion but in recycled material, they’re still very much there – or at the very least could be. And that’s enough to create a significant challenge. PVC-U extrusion is a ‘dark art’. Profile performance is dependent on the strict control of its formulation and by definition, recycled material is an unknown quantity. “If you don’t know the ratios of the formulation you can’t possibly predict how it’s going to perform in extremes of temperature. The differentiation between metal salts or stabilisers can be really very significant”, says Ian Cocken, Director of Sales and Marketing, aluplast. “If material was extruded in the 80s it’s likely to have used barium cadmium, then the industry switched to lead – you cannot possibly know what you’re getting in recycled content and you consequently can’t predict product performance.” The strategy adopted by the industry has for the most part been to put this material into standalone second-grade products, for example reinforcements, to apply a skin of ‘virgin’ material or to foil product. The last two options, however, appear fraught with risk. “The substrate can have a significant impact on surface gloss even and consistency of finish and because it’s ‘unknown’ and variable, it can be very difficult to control”, says Cocken. “Even if you’re simply using it as a substrate for a foil, you can still encounter challenges, creating significant problems down the line.” Processing approaching 200,000 tonnes of PVC-U globally annually, equivalent to 75 per cent of the whole UK and Irish markets combined and with its worldwide customer base manufacturing more than 10million windows per year, aluplast has the scale to apply to product innovation. Its solution to the challenge but also the opportunities delivered by the introduction of recycled PVC-U content into new generation products, is simple in concept but draws on 52 » M AY 2018 » CL EARVI E W- UK . C O M extrusion genius to deliver it. Available as an option on its core Ideal 70 offer but also contemporary new Ideal 4000 system, ecotech, does this by isolating recycled material only in the core web of its product where dimensional stability is not critical. The extrusion process applied by aluplast to deliver this minor miracle in PVC-U profile manufacture, uses pre and post-extrusion product and post fabrication waste plus known source post installation pelletized, PVC-U. Two compound screw feeds then push recycled and virgin material simultaneously through the profile dye to create the profile while maintaining a distinct separation between the two. This separates and at the same time locks recycled material away from areas of the frame visible to the end-user or which perform a structural role, which means that aluplast can guarantee surface and finish quality. “The development of ecotech has represented a significant commitment in the creation of special dyes and the increased investment in running two extruders simultaneously on a single profile but the commercial advantages it delivers to our customers makes that investment very much worth it”, says Ian. “aluplast surface profiles are completely flat with depth of gloss and no pits, no extrusion ‘lines’ and that’s important for consumers. PVC-U is seen as a ‘perfect’ product, there’s a level of end-user expectation - imperfections on the surface are immediately obvious. “This also provides a stable substrate for the millions of metres of foils we supply each year. Critically, having doubled our foiling capacity accompanied by investment in the latest CNC foiling technologies, we are able to under-write our foil offer with absolute confidence.” aluplast for its part, foils approaching 1.5million metres of product each month. This means that it holds thousands of metres of coloured profiles in stock, including two options for anthracite grey, which are available as standard within just days of orders. It also offers special foils in 15-days or less. Ian adds, “The point is we’re not using foils to disguise a sub-standard surface finish. This means that we can offer exactly the same guarantees of performance as on any extrusion using virgin material only. “This should offer comfort to those installers who are currently getting call backs on foils because of inherent flaws in process and consequential surface stability in some other systems. “This aside ecotech offers a point of differentiation and a very positive message about the industry’s commitment to recycle both of which deliver a key competitive advantage.”