MATERIALS | WATERPROOF MEMBRANES
ing flexibility; a higher confidence that extruded sheets will consistently be within specifica- tion; and, a longer service life for installed geomembranes. “A major geomembrane linings
producer set us the technical challenge of developing a new HDPE speciality master-
Right: GSE LiteEarth is an economical alternative to traditional capping systems
as saving money in annual maintenance costs, it says. The product comprises an EPDM geomembrane
that is factory-bonded to synthetic grass. It is manufactured with a UV stabiliser to help retain its colour and tensile properties. The system installs quickly and easily using trenchless earth anchors and a seaming process that does not require welding, stitching or sand ballast. GSE was recently acquired by Solmax, a
Canada-based producer of polyethylene geomem- branes. Both companies are global players in geosynthetic products, supplying containment systems for domestic, hazardous or industrial waste burial sites, retention ponds, fracking and heap leaching pads. Jean-Louis Vangeluwe, president of Solmax, said
the merger would create a company that can compete “in the highly fragmented market of PE geomembrane manufacturing”. He added that the merged company would have
a broader manufacturing footprint and expanded commercial network.
Right: Black masterbatch from Colloids that resists UV weathering was developed specifically for geomembranes
Special use UK-based Colloids has developed two new speciality masterbatches for manufacturing HDPE geomembrane liners. The premium UV grade, MPE9D2203, is carbon black based, and developed for high performance HDPE geomembrane polymer liners that need long term UV weathering properties and high resistance to degradation. The lower cost geomembrane masterbatch
grade, MPE9D2219, is aimed at less demanding geomembrane applications where UV resistance is not critical. The new grades are formulated with a high quality stabilisation system in order to minimise degradation through oxidation at elevated tem- peratures. The resulting benefits include: greater process-
28 FILM & SHEET EXTRUSION | May 2018
www.filmandsheet.com
batch – which would not only provide higher end use performance, but production benefits such as more latitude in the processing window,” said David Helm, senior development technologist at Colloids. “We achieved all these objectives, and validated the technology by carrying out specified HDPE geomembrane tests – as well as getting positive customer feedback after sheet extrusion processing trials.”
Using Geosynthetic Research Institute (GRI) GM13 test methods for HDPE geomembranes, the MPE9D2203 premium UV grade black masterbatch averaged 180 minutes Standard Oxidative Induc- tion Time (OIT) – 80% above the minimum required OIT of 100 minutes (as per ASTM D3895, min avg. 5 samples), says Colloids. The more demanding Retained OIT after 90 days at 85 0C test recorded 70% retention of OIT results – outperforming current market leading grades in comparative testing, it said.
Sheet degradation Researchers at the University of Minnesota in the USA have devised a method for degrading polyethylene sheet samples in an oxidative environment, in order to assess stress cracking. The model system is hot, chlorinated water – and this is applied in a water batch at 60-65°C. Under these conditions, the molecular weight of thin PE sheets was reduced by 60% – and the strain at break was reduced by 90% after 1,000 hours of exposure.
�
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72
