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. A synthetic polymer waterproofing membrane, comprising: an extruded monolayer that includes an inorganic filler, a thermoplastic polyolefin (TPO) plastic compound, and a super water absorbent polymer (SAP), wherein the inorganic filler includes a phyllosilicate clay of the smectite group; wherein the monolayer is configured to be self-supporting, which means that another layer is not necessary for joining, supporting or confining the monolayer; wherein the monolayer does not include a plasticizing material; wherein the monolayer is configured to be self-repairing; wherein the thermoplastic polyolefin (TPO) plastic compound comprises one or more selected from the group consisting of polyethylene, polypropylene, and EVA copolymer, wherein the thermoplastic polyolefin (TPO) plastic compound has a density ranging from 0.820 g/cc to 0.940 g/cc; wherein a content of the thermoplastic polyolefin (TPO) plastic compound is at least 40% by weight of a total weight of the monolayer; and wherein a content of the phyllosilicate clay is at least 15% by weight of a total weight of the monolayer.

2. The membrane, according to claim 1, further comprising an additional layer disposed on a surface of the monolayer.

3. The membrane, according to claim 1, wherein the inorganic filler is a mixture of bentonite and carbon black.

4. The membrane, according to claim 1, further comprising a hydrophobic layer disposed on a surface of the monolayer, wherein the hydrophobic layer does not include clay or water-absorbent polymers, and a thickness of the hydrophobic layer is from 1% to 75% of a total thickness formed by the monolayer and the hydrophobic layer.

5. The membrane, according to claim 4, wherein a thickness of the monolayer is between 25% and 99% of the total thickness formed by the monolayer and the hydrophobic layer.

6. The membrane, according to claim 1, further comprising a reinforcement layer disposed on a surface of the monolayer.

7. The membrane, according to claim 6, wherein the reinforcement layer comprises at least one reinforcing mesh.

8. The membrane, according to claim 7, wherein the reinforcing mesh is made of a material selected from polyester, fibreglass, polypropylene or combinations of thereof.

9. The membrane, according to claim 1, wherein the phyllosilicate clay of the smectite group is at least one selected from the group consisting of Montmorillonite, Beidellite, Nontronite, Laponite and fluorohectorites.

10. The membrane, according to claim 1, wherein the super water-absorbent polymer is at least one selected from the group consisting of hydrophilic resin, starch, polyacrylates, polyvinyl alcohol, PVA, PVOH, cross-linked sodium carboxymethyl cellulose, polyacrylic acid polymers, cross-linked polyvinyl alcohol, calcium alginate, and starch-g-sodium acrylate copolymer.

11. The membrane, according to claim 1, wherein the monolayer includes at least 45% by weight of thermoplastic polyolefin (TPO) plastic compound.

12. The membrane, according to claim 1, wherein the monolayer includes at least 50% by weight of the inorganic filler.

13. The membrane, according to claim 1, wherein the monolayer includes at least 50% by weight of the phyllosilicate clay of the smectite group.

14. The membrane, according to claim 1, wherein the phyllosilicate clay of the smectite group comprises bentonite.

15. A method for manufacturing the membrane according to claim 1, the method comprising: introducing in an extruder a composition including the inorganic filler, the (TPO) compound, and the super water absorbent polymer (SAP), melting the composition, extruding the melted composition in a shape of a membrane, cooling the membrane by calendering, and winding up the membrane.

Description

DESCRIPTION OF THE FIGURES

(1) 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:

(2) 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.

(3) FIG. 2 shows a schematic representation of a superabsorbent polymer in the dry state, with the curled coil shape.

(4) 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).

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

(6) FIG. 5 shows a schematic representation of a superabsorbent molecule.

(7) FIG. 6 shows a schematic representation of a superabsorbent polymer mesh.

(8) FIG. 7 shows a multilayer membrane object of the invention.

DESCRIPTION OF A PREFERRED MODE FOR CARRYING OUT THE INVENTION

(9) 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.

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

(11) 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 1—Membrane 1 and Table 2—Membrane 2).

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

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

(14) 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.

(15) The result was rolls of different lengths and widths of up to 12 metres.

(16) The membranes obtained range in thickness from 1.00 mm to 5.00 mm.

(17) 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.