Pre-applied membranes

Abstract

A laminated pre-applied membrane is provided. The membrane comprises a layer of polyethylene and a rubber or rubber-based layer.

Claims

1. A multi-layer pre-applied membrane comprising a carrier layer comprising polyethylene and a rubber or rubber-based layer against which post-poured building material such as concrete or cement mortar can be cast such that the rubber or rubber-based layer chemically engages with the post-poured building material and such that there is an intimate bond between the membrane and the post-poured building material after it sets, in which the rubber or rubber-based layer comprises process aids and a blend of virgin butyl rubber and reclaimed butyl rubber, and in which the rubber or rubber-based layer further comprises mineral additive that comprises a kaolin to augment the initial bond between the membrane and the post-poured building material and to reduce the bonding time.

2. The membrane according to claim 1, in which the mineral additive comprises kaolinite.

3. The membrane according to claim 1, in which the mineral additive comprises metakaolin.

4. The membrane according to claim 1, in which the mineral additive comprises parakaolin.

5. The membrane according to claim 1, in which the mineral additive comprises calcium carbonate.

6. The membrane according to claim 1, in which the carrier layer is a film having a thickness of approximately 1 mm.

7. The membrane according to claim 1, in which the carrier layer comprises one or more of: LLDPE, LDPE, MDPE, HDPE.

8. The membrane according to claim 1, in which mineral additive is mixed into the rubber or rubber-based layer.

9. The membrane according to claim 1, in which mineral additive is embedded in an upper surface of the rubber or rubber-based layer.

10. The membrane according to claim 1, in which the process aids comprise one or more of: stabilising agents; softening agents; tackifiers; and colourants.

11. The membrane according to claim 1 and further comprising a removable release sheet.

12. The membrane according to claim 1, in which the release sheet has a thickness in the range 0.03 mm to 0.15 mm.

13. The membrane according to claim 1, in which the rubber or rubber-based layer has a thickness in the range 0.4 mm to 1.0 mm.

14. The membrane according to claim 1, in which the carrier layer has a thickness in the range 0.55 mm to 1.25 mm.

15. A membrane that bonds to cement mortar or concrete cast against it, comprising a carrier layer and a rubber or rubber-based layer comprising a mixture of virgin and reclaimed butyl rubber, and kaolin, in which a release liner is provided on the rubber or rubber-based layer, and in which the release liner is dissolvable when cement mortar or concrete is poured onto the membrane.

16. The membrane according to claim 15, in which the rubber or rubber-based layer includes a mineral additive, and in which the kaolin comprises metakaolin and/or parakaolin.

17. The membrane according to claim 15, in which the release liner is formed from PVOH.

18. The membrane according to claim 15, in which the rubber or rubber-based layer comprises a blend of virgin butyl rubber and reclaimed butyl rubber.

19. A construction site having one or more multi-layer pre-applied membranes according to claim 1.

Description

(1) In the description, all orientational terms, such as upper, lower, radially and axially, are used in relation to the drawings and should not be interpreted as limiting on the invention.

(2) FIG. 1 shows an example of a membrane formed in accordance with the present invention.

(3) FIG. 2 shows an example of the constituents of a rubber layer formed in accordance with the present invention.

(4) In other embodiments different percentages of components can, of course, be used;

(5) for example:

(6) Rubber 30% to 75%

(7) Mineral Additive 1% to 30%

(8) Process Aids 5% to 30%

(9) The mineral additive may, for example be: calcium carbonate and/or kaolin and/or kaolinite and/or metakaolin.

(10) FIG. 3 shows an example of the constituents of a rubber layer useful in conjunction with a dissolvable release liner formed in accordance with the present invention.

(11) FIG. 4 shows the constituents of a dissolvable release liner formed in accordance with the present invention.

(12) FIG. 5 below illustrates the improved bond strength between membrane and the concrete after 3 days.

(13) *Sample area=125 cm.sup.2 (5 cm wide by 25 cm long). i.e. the rubber layer of this area size is in contact with the concrete. 180 degree peel adhesion test performed.

(14) The force required to peel of the sample area is recorded above. When comparing sample 1 (control sample with no additive) to sample 2 (sample with mineral additive), the force required to pull sample 2 away from the concrete was more than 5 times than sample 1.

(15) FIG. 6 shows an example of a roll of structural waterproofing pre-applied membrane.

(16) The membrane is a laminated structure with a layer of PE and a butyl rubber layer. In this embodiment a release layer is included.

(17) The PE layer provides puncture resistance. The rubber layer chemically engages with concrete in use.

(18) The dimensions shown are non-limiting.

(19) The rubber layer may have a mineral additive.

(20) Although illustrative embodiments of the invention have been disclosed in detail herein, with reference to the accompanying drawings, it is understood that the invention is not limited to the precise embodiments shown and that various changes and modifications can be effected therein by one skilled in the art without departing from the scope of the invention as defined by the appended claims and their equivalents.