From traditional bitumen membranes in roofing, in use for thousands of years, to the latest single ply synthetic materials, waterproof membranes have enabled dramatic changes in infrastructure and civil engineering. Water reservoirs, dams, landfill and road tunnels are key applications of geosynthetics. On roofs, there are many green projects underway from gardens to solar reflectors to power generation, all supported by appropriate sealing structures. The markets will be reviewed along with the latest technology at the annual AMI international conference in Dusseldorf.
Compounding can enhance properties such as fire resistance and oxidative stability. Minelco supplies halogen-free mineral fire retardants and Huntsman has innovative pigments to enable low carbon cool roofs with coloured roofing systems. Neptune Coatings is also examining cool roofing and comparing the performance of coatings and liquid membranes. In terms of polymer, Dow Chemical has innovative polyolefins for single-ply membrane production. Membrane production technology is constantly under review. The leading supplier of machinery to the bituminous membrane industry, Boato International, will describe new production line technology. For single ply membranes, Davis Standard will report on new developments in production equipment. There are new reinforcements on the market too. James Dewhurst has examined the role of textiles in waterproofing and Milliken has an advanced product for membrane engineering. All efforts are wasted if the membrane is not water-tight at the joints: Leister Technologies has looked at the common mistakes in welding waterproof membranes.
At the 2011 edition of this conference by AMI, some of the discussions included: The predominant form of waterproof membranes in Portugal is bitumen-based, and the civil engineering institute, LNEC, has recently conducted studies into several aspects of the performance: similar work has been carried out by the Slovak University. With the green building initiatives worldwide, construction companies are looking to suppliers to improve their carbon footprint. Waterproof membrane producers have risen to this challenge, for example, Derbigum�s membrane product from recycled material. Davis-Standard has developed technology to minimise the amount of substrate used during the production of reinforced waterproof membranes. Coextrusion and lamination can be used to combine polymers in membranes. Liquid polymer membranes are in the portfolio of many membrane suppliers. Itumex systems apply polymer to waterproof parking areas constructed from prefabricated concrete. High barrier properties are particularly important in geomembranes for landfill applications where leachate can contaminate the surrounding ground water. HR Chempharm�s superabsorbent polymer can be used as an active component in barriers, while Nitroil Polyurea�s products can interact with geotextile. A growing use of geoembranes is in tunnel lining as transportation links develop worldwide. This is a safety-critical application, so companies like Tecnotest AG in Switzerland develop and implement quality control tests. Joining of membranes is another vital factor in membrane integrity: Leister Process Technologies leads the market in welding technologies.