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CN-116887978-B - Thermoplastic sealing device with improved barrier properties

CN116887978BCN 116887978 BCN116887978 BCN 116887978BCN-116887978-B

Abstract

The invention relates to a sealing device (1) comprising a polymeric water barrier layer (2) and a barrier composite layer (3), the barrier composite layer (3) comprising a polymeric tie layer (4), a metallic or polymeric barrier layer (5) and a polymeric protective layer (6). The invention also relates to a method of producing a sealing device and to a roof system comprising a roof mat (10) and a sealing device (1) adhered to a surface of the roof mat (10).

Inventors

  • WANG LANWEI
  • WEI YIZHE
  • WEI QIN

Assignees

  • SIKA技术股份公司

Dates

Publication Date
20260505
Application Date
20210226

Claims (20)

  1. 1. A sealing device (1) which is a waterproofing membrane or roofing membrane comprising: i. A polymeric water barrier layer (2) comprising at least one polymer P1 and having an upper main surface and a lower main surface, A barrier composite layer (3) covering at least a portion of the lower major surface of the polymeric water barrier layer, wherein the barrier composite layer comprises: a) A polymer connection layer (4) comprising at least one polymer P2, said polymer connection layer (4) having a thickness in the range of 15 μm to 350 μm, B) A barrier layer (5), and C) A polymeric protective layer (6), wherein The polymeric tie layer (4) is arranged between the polymeric water barrier layer (2) and the barrier layer (5), and wherein the barrier layer (5) is a metallic barrier layer or a polymeric barrier layer comprising at least one polymer P3 selected from the group consisting of ethylene-vinyl alcohol and polyamide, and the polymeric protective layer (6) comprises at least one polymer P4 selected from the group consisting of polyester, polyamide and polycarbonate.
  2. 2. The sealing device according to claim 1, wherein the polymeric water barrier layer (2) and the polymeric connecting layer (4) are polyolefin-based layers.
  3. 3. The sealing device according to claim 1, wherein the at least one polymer P1 and P2 is selected from the group consisting of ethylene copolymers, polyethylene, propylene copolymers and polypropylene.
  4. 4. A sealing device according to any of the preceding claims 1 to 3, wherein the at least one polymer P1 represents at least 35% by weight of the total weight of the polymeric water barrier layer (2).
  5. 5. A sealing device according to any of the preceding claims 1 to 3, wherein the at least one polymer P1 represents at least 45% by weight of the total weight of the polymeric water barrier layer (2).
  6. 6. A sealing device according to any of the preceding claims 1 to 3, wherein the polymeric water barrier layer (2) has a thickness in the range of 0.25mm to 5.0 mm.
  7. 7. A sealing device according to any of the preceding claims 1 to 3, wherein the polymeric water barrier layer (2) has a thickness in the range of 0.5mm to 3.5 mm.
  8. 8. A sealing device according to any of the preceding claims 1 to 3, wherein the at least one polymer P2 represents at least 50% by weight of the total weight of the polymeric connecting layer (4).
  9. 9. A sealing device according to any of the preceding claims 1 to 3, wherein the at least one polymer P2 represents at least 65% by weight of the total weight of the polymeric connecting layer (4).
  10. 10. A sealing device according to any of the preceding claims 1 to 3, wherein the polymeric connection layer (4) has a thickness in the range of 35 to 250 μm.
  11. 11. A sealing device according to any of the preceding claims 1 to 3, wherein the polymeric connection layer (4) has been heat laminated to at least a portion of the lower main surface of the polymeric waterproof layer (2) in a manner providing a direct bond between the polymeric connection layer (4) and the polymeric waterproof layer (2).
  12. 12. A sealing device according to any one of the preceding claims 1 to 3, wherein the barrier layer (5) is a metallic barrier layer, or Wherein the barrier layer (5) is a polymeric barrier layer comprising ethylene-vinyl alcohol as the at least one polymer P3, the at least one polymer P4 is selected from the group consisting of polyesters and polyamides, and the barrier composite layer (3) further comprises a tie layer (7) arranged between the barrier layer (5) and the polymeric tie layer (4), or Wherein the barrier layer (5) is a polymeric barrier layer comprising polyamide as the at least one polymer P3, the at least one polymer P4 is a polyester, and the barrier composite layer (3) further comprises a tie layer (7) arranged between the barrier layer (5) and the polymeric tie layer (4).
  13. 13. Sealing device according to claim 12, wherein the barrier layer (5) is an aluminium or aluminium alloy film.
  14. 14. The sealing device according to claim 12, wherein the tie layer (7) comprises at least one maleic anhydride grafted polyolefin.
  15. 15. The sealing device of claim 14, wherein the maleic anhydride grafted polyolefin is selected from the group consisting of maleic anhydride grafted polyethylene and maleic anhydride grafted polypropylene.
  16. 16. The sealing device of claim 12, wherein the metal barrier layer has a thickness in the range of 1-50 μιη.
  17. 17. The sealing device of claim 16, wherein the metal barrier layer has a thickness in the range of 1.5-35 μιη.
  18. 18. The sealing device of claim 12, wherein the polymeric barrier layer has a thickness in the range of 1-300 μιη.
  19. 19. The sealing device of claim 12, wherein the polymeric barrier layer has a thickness in the range of 2.5-200 μιη.
  20. 20. The sealing device according to claim 12, wherein the polymeric protective layer (6) has a thickness of 1-150 μm.

Description

Thermoplastic sealing device with improved barrier properties Technical Field The present invention relates to the field of waterproofing above-ground and below-ground building structures by using watertight thermoplastic sealing devices. In particular, the present invention relates to thermoplastic waterproofing and roofing membranes for sealing building substrates against water leakage. Background In the construction field, polymeric sheets, commonly referred to as membranes, are used to protect underground and above-ground constructions (e.g., basements, tunnels, and flat and low-pitch roofs) from penetrating water. For example, membranes are applied to prevent water from entering through cracks in concrete structures due to building settlement, load deflection, or shrinkage of the concrete. Waterproof roofing membranes for flat and low-pitch roofing structures may be provided as a single or multi-layer membrane system. In a single layer system, the roof substrate is covered with a roofing membrane consisting of a single waterproof layer, which may be reinforced with a reinforcing layer, such as a layer of fibrous material. In a multilayer system, roofing membranes are used which consist of a plurality of water-repellent layers of different or similar materials. Single layer films have the advantage of lower production costs compared to multi-layer films, but they are also less resistant to mechanical damage caused by perforation by sharp objects. Common materials for waterproofing and roofing membranes include plastics, particularly thermoplastics such as plasticized polyvinyl chloride (p-PVC), thermoplastic olefins (TPE-O, TPO), and elastomers such as ethylene-propylene diene monomer (EPDM) rubber. Asphalt materials are also used to provide films because they provide good environmental resistance and relatively low cost compared to thermoplastic polymer materials. Asphalt compositions are typically modified with synthetic polymers to increase UV radiation resistance, toughness, and flexibility at low temperatures. The film is typically delivered to the job site in roll, non-roll form, and cut into suitable pieces to adhere to the surface of the substrate to be water-repellent. The substrate to which the film is adhered may be composed of various materials according to the installation site. The substrate may be, for example, concrete, metal or wood, or it may comprise a decking and/or insulation board and/or an existing waterproof or roofing membrane. Waterproof and roofing membranes can be adhered to a substrate by using several techniques, for example by contact adhesion or by using self-adhesive membranes. In contact bonding, the surfaces of the film and the substrate are first coated with a solvent or water-based contact adhesive, and then the adhesive films are bonded to each other. The volatile components of the contact adhesive are "flashed" to provide a partially dried adhesive film before the film contacts the surface of the substrate. The main drawbacks of contact bonding relate to the slow installation process compared to self-adhesive films, significant emissions of volatile compounds in the case of solvent-based adhesives, and limited application at low temperatures in the case of water-based contact adhesives. The self-adhesive film comprises a pre-applied layer of adhesive composition coated on the film surface. Typically, the pre-applied adhesive layer is also covered with a release film to prevent premature unwanted adhesion and to protect the adhesive layer from moisture, dirt and other environmental factors. In use, the release film is removed and the film is secured to the substrate without the use of additional adhesive. Self-adhesive films having a pre-applied adhesive layer covered by a release film are also known as "peel and stick films". In some cases, migration of chemicals from the adhesive layer into the membrane can be a significant problem, particularly for TPO-based roofing membranes. For example, in the case of contact bonding, the solvent-based adhesive is applied directly to the backing layer of the film, and volatile compounds can migrate from the adhesive composition into the polymer matrix of the film, resulting in a shortened service life of the film. The nonwoven layer of the fleece/felt backed roofing membrane may act as a barrier layer against compound migration, but the protection capacity is only partial due to the porous structure of the nonwoven. Another disadvantage of wool-and felt-backed films compared to bare-backed films includes higher production costs. The self-adhesive film contains a factory applied adhesive layer on the lower surface of the film. The adhesive layer may be a butyl rubber based adhesive or a bitumen based adhesive, which may contain a variety of chemical compounds that can migrate from the adhesive layer into the film. Accelerated aging tests using a QUVB tester have shown that some commercially available TPO-based self-adhesive lay