MULTI-LAYER FILM, COVER MATERIAL, ITS USE AND METHOD OF MANUFACTURE

Abstract

In an embodiment a multilayer film includes a first layer having a polypropylene heterophasic copolymer and/or a polypropylene homopolymer, a second layer having a polyamide copolymer and/or a polyamide homopolymer and a nucleating agent and a third layer including a coupling agent, the third layer being disposed between the first layer and the second layer, wherein the multilayer film has an asymmetric layer sequence.

Claims

1.-18. (canceled)

19. A multilayer film comprising: a first layer comprising a polypropylene heterophasic copolymer and/or a polypropylene homopolymer; a second layer comprising a polyamide copolymer and/or a polyamide homopolymer and a nucleating agent; and a third layer comprising a coupling agent, the third layer being disposed between the first layer and the second layer, wherein the multilayer film has an asymmetric layer sequence.

20. The multilayer film according to claim 19, wherein the nucleating agent comprises: an inorganic filler selected from the group consisting of metal oxides, metal salts, silicates, boron nitrides and a mixture thereof, a filling and reinforcing agent selected from the group consisting of talc, synthetic silicas, kaolin and a mixture thereof, and a colorant, a pigment or a mixture thereof.

21. The multilayer film according to claim 19, wherein the nucleating agent has an average particle size (D50), measured by gravity liquid sedimentation according to ISO 13317-3:2001 (Determination of particle size distribution by gravitational liquid sedimentation methods-Part 3: X-ray gravitational technique), with an accumulation degree of 50% of 0.5 to 5 m.

22. The multilayer film according to claim 19, wherein the nucleating agent is present in the second layer in a concentration of 0.1 to 5% by weight.

23. The multilayer film according to claim 19, wherein the multilayer film consist of the first layer, the second layer, and the third layer.

24. The multilayer film according to claim 19, wherein the second layer consists of a layer comprising a polyamide copolymer.

25. The multilayer film according to claim 19, wherein the second layer consists of multiple layers and comprises individual layers of a polyamide homopolymer.

26. The multilayer film according to claim 25, wherein an amount of polyamide homopolymer relative to an total amount of polyamide in all layers of the second layer is up to 65% by weight.

27. The multilayer film according to claim 19, wherein a thickness of the second layer relative to a total thickness of the first layer, the second layer and the third layer is 20% to 75%.

28. The multilayer film according to claim 19, wherein a total thickness of the multilayer film is 40 m to 140 m.

29. The multilayer film according to claim 19, wherein a tear strength of the multilayer film is more than 110 N according to ASTM 1970.

30. The multilayer film according to claim 19, wherein a ratio of a breaking force at break in a first machine direction to a transverse direction to a second machine direction is less than 1.1 according to ASTM 1970.

31. A method for manufacturing the multilayer film according to claim 19, the method comprising: coextruding the first layer, the second layer, and the third layer.

32. A method comprising: using of the multilayer film according to claim 19 for coating or for producing cover materials or an adhesive tape.

33. A cover material comprising: the multilayer film according to claim 19; and an adhesive composition.

34. The cover material according to claim 33, wherein the adhesive composition is bitumen or a self-adhesive waterproofing composition.

35. The cover material according to claim 33, wherein the adhesive composition is applied to the second layer.

36. A method comprising: using of the cover material according to claim 33 as a building material, for roofing, for external cladding, for covering buildings or parts of buildings, or for covering pipes.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0050] FIG. 1 shows a multilayer film (100) with asymmetric layer sequence comprising a first layer (110) comprising polypropylene copolymer and/or polypropylene homopolymer; a second layer (130) comprising polyamide copolymer and/or polyamide homopolymer; wherein between the first layer (110) and the second layer (130) there is a third layer (120) comprising an adhesion promoter.

[0051] FIG. 2 shows a cover material (200) comprising a multilayer film (100) as shown in FIG. 1 and a tacky composition (140) disposed on the second layer.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0052] FIG. 1 shows a schematic cross-section through a multilayer film 100 according to at least one embodiment according to the application. The multilayer film 100 comprises a first layer 110, a second layer 130, and a middle layer 120. The middle layer 120 is an adhesion promoter layer. In a preferred embodiment, the multilayer film is a three-layer film comprising a first outer layer 110, a second outer layer 130, and a middle layer 120.

[0053] The multilayer film 100 may have a total thickness of 40 to 140 m, preferably 50 to 130 m, in particular 55 to 120 m. The first layer 110 may have a layer thickness of 5 to 50 m, in particular 10 to 30 m. The third layer comprising adhesion promoters can have a layer thickness of 1 to 30 m, in particular 2 to 20 m. The second layer 130 can have a layer thickness of 5 to 100 m, preferably 10 to 80 m, in particular 20 to 80 m.

[0054] The first layer 110 comprises homo polypropylene, for example 40 to 60 wt %, and polypropylene heterophasic (block) copolymer (ethylene content 7-9 wt %), for example 15 to 30 wt % polypropylene heterophasic (block) copolymer (ethylene content 7-9 wt %). The second layer 130 comprises at least 30 wt % copolyamide, for example 80 to 100 wt % copolyamide. In particular, the copolyamide may comprise isophorone diamine units, such as polyamide 6/IPDI. The adhesion promoter layers 120 may include a polypropylene polymer modified or grafted with maleic anhydride.

[0055] The film shown in FIG. 1 may, for example, be a so-called blown film, for example a three-layer blown film. On the side of the second layer (outer layer) 130 facing away from the third layer (middle layer) 120, an adhesive layer and, if necessary, a protective layer or a protective film may be applied (not shown here).

[0056] FIG. 2 shows a schematic cross-sectional view of a sealing material 200 according to at least one embodiment. The cover material 200 comprises a multilayer film 100 as described, for example, for FIG. 1. The multilayer film 100 is laminated to an adhesive composition 140 comprising or consisting of, for example, bitumen. The cover material 200 shown in FIG. 2 may be embodied, for example, as a cover membrane, in particular a bituminous cover membrane, with the multilayer film 100 as a surface coating or surface film, and may be suitable for waterproofing or covering roofs or other parts of buildings.

[0057] In this regard, the multilayer film 100 protects the water-impermeable material 70 from harmful gases, for example atmospheric oxygen, and acts as an oil barrier, particularly during installation of the waterproofing material.

EXAMPLES

[0058] In the examples, the abbreviations listed in Table 1 below are used:

TABLE-US-00001 TABLE 1 Density Marking Designation Tm [ C.] [g/cm.sup.3] PP Homo Polypropylene homopolymer 166 0.9 of the company Borealis PP HeCo Polypropylene heterophasic 164 0.9 (block) Copolymer of the company Braskem or Borealis (ethylene content 7-9 wt. %) TPO Polypropylene polyethylene 140 0.89 Copolymer with low EModulus HV, HV1 Adhesion promoting 160 0.9 polymer, with Maleic anhydride groups modified polypropylene Homopolymer of the company Mitsui HV2 Adhesion promoting 63 0.87 polymer, with Maleic anhydride groups modified thermoplastic Elastomer from the company DowDuPont CoPA Copolyamide formed from 212 1.13 eCaprolactam, isophorone diamine and isoterephtalic acid, with an isophorone diamine component of approx. 5% of the company Lanxess HomoPA Polyamide 6 from the 222 1.14 company Lanxess UV UV stabilizing masterbatch Not 0.92 additive I of the company Constab on specified the basis of a sterically hindered Amine derivative UV UV stabilizing masterbatch of Not 0.93 Additive II the Schulmann company with specified a Additive proportion of 10% Color Color masterbatches from Not 1.14 various companies specified

[0059] In the examples, three-layer films were produced from layers 110, 120 and 130 by blown film coextrusion. The layers had the following composition:

Example 1

TABLE-US-00002 TABLE 2 Example 1 (100 m) Share in the Layer Description shift thicknesses Layer layer Description [%] [m] 130 Polyamide 1 CoPA 96.5 16 Anti-blocking 2 agent (talc) Nucleating agent 1 Processing aids 0.5 130 Polyamide 2 CoPA 98.5 22 Nucleating agent 1 Processing aids 0.5 130 Polyamide 3 CoPA 68.5 10 h-PA (PA6) 30 Nucleating agent 1 Processing aids 1.5 120 Bonding agent HV1 98.5 11 UV2 1.5 110 Polypropylene 1 PP-Homo 54.5 8, 8, 8 PP HeCo 30 UV2 2 Color (white) 13.5 110 Polypropylene 2 PP-Homo 52 17 PP HeCo 30 UV2 2 Anti-blocking 2 agent (talc) Processing aids 0.5 Color (white) 13.5

Example 2

TABLE-US-00003 TABLE 3 Example 2 (80 m) Share in the Layer Description shift thicknesses Layer 1 layer Description [%] [m] 130 Polyamide 1 CoPA 96.5 16 Anti-blocking 2 agent (talc) Nucleating agent 1 Processing aids 0.5 130 Polyamide 2 CoPA 98.5 22 Nucleating agent 1 Processing aids 0.5 130 Polyamide 3 CoPA 68.5 10 h-PA (PA6) 30 Nucleating agent 1 Processing aids 1.5 120 Bonding agent HV1 98.5 11 UV2 1.5 110 Polypropylene 1 PP-Homo 54.5 12 (3 4) PP HeCo 30 UV stabilizer 2 Color (white) 13.5 110 Polypropylene 2 PP-Homo 52 9 PP HeCo 30 UV stabilizer 2 Anti-blocking 2 agent (talc) Processing aids 0.5 Color (white) 13.5

COMPARATIVE EXAMPLES

[0060] In the Comparative Examples, five-layer films were produced from successive layers 1 to 5 by blown film coextrusion. The layers had the following composition:

Comparative Example 1

TABLE-US-00004 TABLE 4 Comparative Example 1 Layer Total Proportion thickness thickness Layer Material [wt. %] [m] [m] 1 PP Homo 30 44 125 PP HeCo 42.5 UV additive I 2.5 Color 5 EBA 20 2 HV1 74 6 UV Additive II 1 PP Homo 25 3 CoPA 100 25 4 HV1 74 6 UV Additive II 1 PP Homo 25 5 PP Homo 30 44 PP HeCo 42.5 UV additive I 2.5 Color 5 EBA 20

Comparative Example 2

TABLE-US-00005 TABLE 5 Comparative Example 2 Layer Total Proportion thickness thickness Layer Material [wt. %] [m] [m] 1 PP Homo 30 34 100 PP HeCo 42.5 UV additive I 2.5 Color 5 EBA 20 2 HV1 74 6 UV Additive II 1 PP Homo 25 3 CoPA 100 20 4 HV1 74 6 UV Additive II 1 PP Homo 25 5 PP Homo 30 34 PP HeCo 42.5 UV additive I 2.5 Color 5 EBA 20

Comparative Example 3

TABLE-US-00006 TABLE 6 Comparative Example 3 Layer Total Proportion thickness thickness Layer Material [wt. %] [m] [m] 1 PP Homo 30 27 80 PP HeCo 42.5 UV additive I 2.5 Color 5 EBA 20 2 HV1 74 5 UV Additive II 1 PP Homo 25 3 CoPA 100 16 4 HV1 74 5 UV Additive II 1 PP Homo 25 5 PP Homo 30 27 PP HeCo 42.5 UV additive I 2.5 Color 5 EBA 20

Comparative Example 4

TABLE-US-00007 TABLE 7 Comparative Example 4 Layer Total Proportion thickness thickness Layer Material [wt. %] [m] [m] 1 PP Homo 30 44 125 TPO 62.5 UV additive I 2.5 Color 5 2 HV2 20 6 UV Additive II 1 PP Homo 79 3 CoPA 100 25 4 HV2 20 6 UV Additive II 1 PP Homo 79 5 PP Homo 30 44 TPO 62.5 UV additive I 2.5 Color 5

Comparative Example 5

TABLE-US-00008 TABLE 8 Comparative Example 5 Layer Total Proportion thickness thickness Layer Material [wt. %] [m] [m] 1 PP Homo 30 35 100 TPO 62.5 UV additive I 2.5 Color 5 2 HV2 20 5 UV Additive II 1 PP Homo 79 3 CoPA 100 20 4 HV2 20 5 UV Additive II 1 PP Homo 79 5 PP Homo 30 35 TPO 54 UV additive I 2.5 Color 13.5

Evaluation of the Slides

[0061] The films were tested for their tear strength at break according to ASTM 1970.

TABLE-US-00009 TABLE 9 Comparative Try Example 1 Example 2 Example 1 Bond adhesion vs. 70.5 Adhesive 70.1 Cohesion 68.8 Adhesive bitumen I [N] fracture break fracture Bond adhesion vs. 110.8 Cohesion 115 Cohesion 93.1 Cohesion bitumen II [N] break break fracture
Bitumen I and Bitumen II are Bitumen Masses from Different Manufacturers

TABLE-US-00010 TABLE 10 Tearing Tearing force at force at Ratio of break in break in breaking Thickness direction direction force md ASTM Film type [m] md [N] md [N] to cd 154 [N] Example 1 100 139.1 128 1.085 Example 2 80 142.2 112.4 1.26 Comparative 125 157 140 1.12 290 Example 1 Comparative 100 132 116 1.14 231 Example 2 Comparative 80 106 90 1.17 225 Example 3 Comparative 125 110.1 101.3 1.09 263 Example 4 Comparative 100 78.6 71.1 1.11 174 Example 5