MATERIAL PROPERTIES

1. What are the typical roll dimensions of Poly-Flex geomembranes?

   All Poly-Flex rolls are 23 feet wide. The roll lengths range from 300 feet up to 1,550 feet depending on the material type and thickness. The gross weights are approximately 3,500 lbs. Please refer to the Material Specification Section.

2. What is the permeability of the Poly-Flex liners?

   Poly-Flex liners have a pseudo coefficient of permeability in the order of 10^-13 cm/sec vs. compacted clay at 10^-7cm/sec

3. What is the moisture vapor transmission rate (MVTR) of the Poly-Flex liners?

   The permeability of Poly-Flex liners is expressed as the Moisture Vapor Transmission Rate (MVTR) as measured by the ASTM D E96 test method. The property is expressed in grams/unit area/day. Please refer to inherent properties of polyethylene liners located in Material Specifications.

4. What are the advantages of Poly-Flex textured liners?

   Our blown-film textured liners have smooth edges and are covered by U.S. Patent Nos. 5,763,047 and 5,804,112. The blown-film texturing provides increased friction angles for higher stability on steep slope applications. Additionally, the smooth edges result in easier, more cost-effective, more consistent, and better welding.

5. What is the minimum degree of roughness (texturing) a textured liner should have?

   The minimum industry standard specification GRI GM13 and GRI GM17, require a minimum Asperity Height of 10 mils for textured HDPE and textured LLDPE geomembranes.

6. Are there any adhesives, tapes or glues that are suitable for joining Poly-Flex liners?

   There are no adhesives, tapes or glues that provide a permanent, watertight bond to polyethylene.

7. Can Poly-Flex liners of different thickness or textures be welded to each other?

   Yes. Poly-Flex liners with thickness or texture differences of 20 mils or less can be fusion welded together. Liners with thickness or texture differences of greater than 20 mils should be extrusion welded together.

8. Can Poly-Flex liners of different densities be welded to each other?

   Yes. Welding temperature adjustments must be made to achieve a successful weld. When extrusion welding, the lower density welding rod should be used.

9. What are the advantages of LLDPE over PVC geomembrane?

   The advantages are as follows:

   • LLDPE has resistance to a wider range of chemicals as compared to PVC.
   • LLDPE is immune from biological attack by microorganisms. Microorganisms could attack PVC and use the plasticizer as a source of food.
   • LLDPE is resistant to burrowing animals, PVC is not.
   • LLDPE has a lower permeability to methane than PVC.
   • LLDPE has a lower moisture vapor transmission rate than PVC.
   • LLDPE retains its physical properties due to long-term soil burial. PVC's physical properties diminish in time due to loss of plasticizer.
   • LLDPE is resistant to ultra-violet light, PVC is not.
   • LLDPE remains flexible at temperatures well below freezing at -25°C. PVC loses its flexibility and becomes brittle at -25°C

1. Are Poly-Flex liners resistant to chemical attack? Which chemicals?

   Chemical resistance as applied to geomembranes is a relative term. In its strictest form, chemical compatibility, as the term applies to this industry, implies that a chemical has no effect on the liner. However, from an engineering perspective, chemical compatibility means that a liner will survive exposure to a chemical, even though the chemical could have some effects on the liner, without causing the liner to fail. Poly-Flex liners provide a high degree of chemical resistance to a wide range of chemicals. Please refer to the chemical resistance section under Technical Information.

2. Which liner should be used for secondary containment, Poly-Flex HDPE or LLDPE? Why?

   Poly-Flex HDPE liners are preferred because most secondary containment projects are for emergency containment of chemicals at high concentrations, such as fuels and acids. The Poly-Flex HDPE liners provide a higher degree of chemical resistance as compared to LLDPE liners.

DURABILITY

1. Can Poly-Flex liners be exposed to sunlight for a long period of time? How long?

   Yes. Poly-Flex liners are specifically formulated and manufactured to resist ultra-violet rays. Therefore, they are suitable for use in exposed applications. The liners are expected to last many decades in exposed applications without any detrimental effect from sunlight.

2. What is the elongation or deformation limits of Poly-Flex HDPE and LLDPE geomembranes before they rupture?

   In the multi-axial tension test, ASTM D 5617, the HDPE liners rupture at 15% elongation and the LLDPE liners rupture at 30% elongation.

3. Does thickness affect the elongation or deformation limits?

   Generally, the elongation property of Poly-Flex liners is independent of the material thickness. Although thinner liners deform with less pressure, the ultimate elongation at rupture is nearly the same for all gauges.

4. Does material thickness influence puncture resistance?

   Yes. Thicker liners have higher puncture resistance than the thinner ones.

5. What are the temperatures for material that can be contained by Poly-Flex liners?

   Poly-Flex geomembranes are thermoplastic materials, hence their physical properties are temperature dependent. The material becomes softer and more flexible at higher temperatures and stiffer and stronger at lower temperatures. We specify maximum use temperatures of 160° F for HDPE and 140° F for LLDPE liners.

6. What is the cold temperature resistance of Poly-Flex liners?

   Poly-Flex liners pass the low temperature brittleness test at -70¡ C (-94¡ F) according to the ASTM D 746.

7. Why do Poly-Flex liners have wrinkles?

   Polyethylene liners expand and contract as the sheet temperature changes. This thermal expansion/contraction will cause the liner to grow or shrink with variance in temperature.

8. What is the life expectancy of Poly-Flex HDPE and LLDPE liners?

   The life expectancy of Poly-Flex liners depends on the environment in which they are installed. Exposure to high temperatures, certain chemicals, constant loads, and adverse site conditions shorten the life of the liners. Under normal conditions, Poly-Flex HDPE and LLDPE liners are expected to last for many decades.

Disclaimer: These answers are provided for informational purposes only and are not intended as a warranty or guarantee. Poly-Flex, Inc. assumes no responsibilities in connection with the use of this information. Oct. 99.