SELF-SUPPORTING SYNTHETIC POLYMER WATERPROOFING MEMBRANE WITH SELF-REPAIR PROPERTIES

Abstract

The self-supporting synthetic polymer waterproofing membrane with self-repairing properties relates to a self-repairing synthetic waterproof membrane, applicable in the construction sector. This membrane can be monolayer or multilayer. The composition of these membranes comprises thermoplastic polymers, smectite-type clays and super water-absorbent polymers.

Claims

1-13. (canceled)

14. A synthetic polymer waterproofing membrane comprising an extruded self-supporting monolayer without reinforcement or plasticising materials, with between 1% and 95% by weight of inorganic filler of the phyllosilicate-type clays of the smectite group, and plastic compounds of the Polyolefin Thermoplastic (TPO) type and super water absorbent polymers (SAP).

15. The membrane, according to claim 14, comprising at least one additional layer to the self-repairing mono layer such that the inorganic filler portion consists of between 15% and 75% by weight of the total composition of the membrane.

16. The membrane, according to claim 14, wherein that the inorganic filler is a mixture of phyllosilicate of the smectite group (bentonite) with other inorganic fillers such as carbon black.

17. The membrane, according to claim 15, comprising at least one outer hydrophobic layer without clay or water-absorbent polymers on at least one side of the self-supporting monolayer, and representing a thickness ranging from 1% to 75% of the total thickness formed by the self-supporting monolayer and the at least one outer layer.

18. The membrane, according to claim 17, wherein the self-supporting monolayer has a thickness that represents between 25% and 99% of the total thickness of the membrane formed by the self-supporting monolayer and the at least one outer layer.

19. The membrane, according to claim 15, comprising a reinforcement layer additional to the monolayer.

20. The membrane, according to claim 14, having a thickness greater than 0.01 mm.

21. The membrane, according to claim 19, wherein the reinforcing layer comprises at least one reinforcing mesh.

22. The membrane, according to claim 21, wherein the reinforcement mesh is made of different materials, such as polyester, fibreglass, polypropylene or combinations of thereof.

23. The membrane, according to claim 14, wherein the phyllosilicate-type clays of the smectite group are chosen, among others, between Montmorillonite, Beidellite, Nontronite, Laponite and fluorohectorites.

24. The membrane according to claim 14, wherein the Polyolefin Thermoplastic (TPO) type plastic compounds are chosen, among others, between polyethylene, polypropylene or EVA copolymer.

25. The membrane, according to claim 14, wherein the water-absorbent polymers are hydrophilic resin, starch-based, polyacrylates, polyvinyl alcohol, PVA or PVOH, among others, and cross-linked sodium carboxymethyl cellulose, polyacrylic acid polymers, cross-linked polyvinyl alcohol, calcium alginate or starch-g-sodium acrylate copolymer.

26. A method for manufacturing a synthetic polymer waterproofing membrane with a self-supporting monolayer without reinforcement or plasticising materials, comprising the following steps: introduction in an extruder between 1% and 95% by weight of an inorganic filler of the phyllosilicate-type clays of the smectite group, plastic compounds of the Polyolefin Thermoplastic (TPO) type and super water absorbent polymers (SAP), melting the previous components, extruding the melted components in the shape of a membrane, cooling the membrane by calendering, and winding up the membrane.

Description

DESCRIPTION OF THE FIGURES

[0071] To complement the description being made and to help better understand the features of the invention, a set of drawings is attached to the present specification as an integral part thereof, wherein in an illustrative and not limiting manner the following has been represented:

[0072] FIG. 1 shows a schematic representation of the structure of sodium bentonite, or Montmorillonite, which is configured by stacked octahedral units mainly of aluminium in the form of a mesh, sandwiched between two planes of silicon (Si) tetrahedra, which include the simple or hydrated compensation cations.

[0073] FIG. 2 shows a schematic representation of a superabsorbent polymer in the dry state, with the curled coil shape.

[0074] FIG. 3 shows the schematic procedure of mixing a molecule of a superabsorbent polymer in the dry state when it is placed in water (H2O).

[0075] FIG. 4 shows the schematic procedure of mixing a mesh of superabsorbent polymer in water (H2O).

[0076] FIG. 5 shows a schematic representation of a superabsorbent molecule.

[0077] FIG. 6 shows a schematic representation of a superabsorbent polymer mesh.

[0078] FIG. 7 shows a multilayer membrane object of the invention.

DESCRIPTION OF A PREFERRED MODE FOR CARRYING OUT THE INVENTION

[0079] A preferred mode for carrying out the object of this application will be described below, although the present invention is not limited to this particular example.

[0080] A formulation that includes the following components has been used for producing and obtaining self-supporting self-repairing membranes: [0081] Thermoplastic polyolefin (TPO) resins with densities between 0.820 g/cc and 0.940 g/cc. [0082] Sodium Bentonite. [0083] Sodium Polyacrylate such as SAP. [0084] Carbon Black Masterbatch and other additives, excluding plasticisers and lubricants.

[0085] This formulation has been processed in a co-rotating twin spool machine (extruder) attached to a flat header, and the formulations of membrane 1 and membrane 2 are shown in the following two tables (Table 1Membrane 1 and Table 2Membrane 2).

TABLE-US-00001 TABLE 1 Membrane 1. Component Percentage Employed TPO 45 Sodium Bentonite 50 Sodium Polyacrylate 5

TABLE-US-00002 TABLE 2 Membrane 2. Component Percentage Employed TPO 40 Sodium Bentonite 50 Sodium Polyacrylate 5 Carbon Black and other additives 5

[0086] The molten material flows out in the form of a membrane from the header of the extrusion machine. This hot, molten membrane is made to pass through the rollers of the calender where the membrane is subjected to a suitable cooling process. Once the resulting membrane is adequately cooled it is wound onto a spool.

[0087] The result was rolls of different lengths and widths of up to 12 metres.

[0088] The membranes obtained range in thickness from 1.00 mm to 5.00 mm.

[0089] FIG. 7 shows an example of a multilayer membrane object of the invention, in which there is a self-supporting middle layer (2), according to claim 1, with at least one outer hydrophobic layer (1) on each side without clay or water-absorbing polymers, and representing a thickness ranging from 1% to 75% of the total thickness. The self-supporting middle layer preferably has a thickness representing between 25% and 99% of the total and, in addition, the outer layers (1) serve as reinforcement layers. Said reinforcement layer or layers may comprise at least one reinforcement mesh, which can be made of different materials such as polyester, fibreglass, polypropylene or combinations thereof.