Adhesion promoter composition for polyolefinic membranes

Abstract

Composition, comprising—at least one organic polymer,—at least one monomer from the group of acrylates,—at least one catalyst from the group of tertiary organic amines,—at least one solvent.

Claims

1. A composition comprising at least one organic polymer comprising: a hard chlorinated polyolefin with a chlorination degree of 20-30% and a molecular weight of at least 150,000 g/mol (Poly1); or a soft chlorinated polyolefin with a chlorination degree of 20-30% and a molecular weight of at least 100,000 g/mol (Poly2); at least one monomer from the group of alkyl acrylate esters and alkyl methacrylate esters; at least one catalyst from the group of tertiary organic amines; and at least one solvent.

2. The composition of claim 1, wherein the at least one organic polymer further comprises: a hard polyolefin with a chlorination degree of 20-30%, a maleic acid anhydride content of 1 to 2% and a molecular weight of 60,000 g/mol (Poly3); or a soft polyolefin with a chlorination degree of 20-30%, a maleic acid anhydride content of 1 to 2% and a molecular weight of 65,000 g/mol (Poly4).

3. The composition of claim 1, wherein the at least one catalyst from the group of tertiary organic amines comprises an aniline derivative.

4. The composition of claim 1, wherein the at least one solvent comprises an alkyl aromatic solvent.

5. The composition of claim 1 further comprising an adhesion promoter.

6. A method for surface treatment of a polyolefinic substrate, the method comprising: applying a composition to the surface of a polyolefinic substrate, and subsequently drying the composition, wherein the composition comprises: at least one organic polymer comprising: a hard chlorinated polyolefin with a chlorination degree of 20-30% and a molecular weight of at least 150,000 g/mol (Poly1); or a soft chlorinated polyolefin with a chlorination degree of 20-30% and a molecular weight of at least 100,000 g/mol (Poly2); at least one monomer from the group of alkyl acrylate esters and alkyl methacrylate esters; at least one catalyst from the group of tertiary organic amines; and at least one solvent.

7. The method of claim 6 further comprising after drying, bonding the polyolefinic substrate to another substrate.

8. The method of claim 6, wherein after the drying of the applied composition, an adhesive is applied.

9. The method of claim 6, wherein the polyolefinic substrate is a waterproofing.

10. The composition of claim 1, wherein the at least one monomer from the group of acrylates comprises a methyl methacrylate, butyl methacrylate, or lauryl methacrylate.

11. The composition of claim 1, wherein the at least one catalyst from the group of tertiary organic amines comprises N,N-bis-(2-hydroxyethyl)-para-toluidine.

12. The composition of claim 1, wherein the at least one solvent comprises xylene.

13. The composition of claim 5, wherein the adhesion promoter comprises: about 1 to 10 parts by weight of the at least one organic polymer; about 3 to 20 parts by weight of the at least one monomer from the group of acrylates; about 3 to 16 parts by weight of the at least one catalyst from the group of tertiary organic amines; and about 54 to 93 parts by weight of the at least one solvent.

14. The composition of claim 5, wherein the adhesion promoter comprises: about 4 to 7 parts by weight of the at least one organic polymer; about 10 to 15 parts by weight of the at least one monomer from the group of acrylates; about 5 to 10 parts by weight of the at least one catalyst from the group of tertiary organic amines; and about 68 to 87 parts by weight of the at least one solvent.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is an illustration of the combination of a combination of a (non-reactive) polymer with a monomer from the group of (reactive) acrylates that, in cooperation with the other components, namely solvent and catalyst, leads to the surprisingly good action as adhesive.

(2) FIG. 2 is a graphic representation of the results set forth in Table 1 of Example 1.

(3) FIG. 3 is a graphic representation of the results set forth in Table 2 of Example 2.

(4) FIG. 4 is a graphic representation of the results set forth in Table 3 of Example 3.

DESCRIPTION OF THE INVENTION

(5) Therefore, the problem of the present invention is to provide compositions that allow a durable and structural bonding of polyolefinic substrates to other substrates. A further problem of the present invention is to provide a method that allows the durable and structural bonding of polyolefinic substrates to other substrates.

(6) It has been discovered surprisingly that the composition according to claim 1 solves this problem.

(7) In addition, the problem is also solved by the method according to claim 9.

(8) Preferred embodiments are indicated in the dependent claims.

WAYS OF CARRYING OUT THE INVENTION

(9) The subject matter of the present invention is a composition comprising at least one organic polymer at least one monomer from the group of acrylates at least one catalyst from the group of tertiary organic amines at least one solvent

(10) The described solvent-containing composition is capable of activating the surface of polyolefinic substrates in such a manner that they subsequently can be durably and structurally bonded with an adhesive, in particular with an acrylate adhesive, to other substrates.

(11) The composition according to the invention is a low-viscosity solvent-containing liquid which is applied to the surface to be treated, preferably by brush application or spraying. After drying, the composition forms a film on the surface, which acts as “polarity mediator” between the materials and which can interact with the polyolefins of the substrate as well as with the components of the adhesive. In addition, the composition contains reactive substances that participate in the curing of the adhesive and thus allow a permanent bonding of the surface.

(12) In the present document, substance names starting with “poly,” such as polyolefin, for example, denote substances that contain formally two or more of the functional groups occurring in their name per molecule.

(13) In the present document, the term “polymer” covers, on the one hand, a collective of chemically homogeneous macromolecules that differ, however, with regard to polymerization degree, molecular weight and chain length, and that were produced by a polyreaction (polymerization, polyaddition, polycondensation). On the other hand, the term also covers derivatives of such a collective of macromolecules from polyreactions, that is to say compounds that were obtained by reactions, such as, for example, additions or substitutions, of functional groups on given macromolecules and that can be chemically homogenous or chemically inhomogeneous. The term moreover also covers so-called prepolymers, that is to say reactive oligomer preadducts whose functional groups participate in the structure of macromolecules.

(14) In the present document, the term “molecular weight” always denotes the number average molecular weight M.sub.n.

(15) Typical application fields of the composition according to the invention are the pretreatment of polyolefinic substrates for bonding in the context of roofing, waterproofing as well as bonding of waterproofing membranes for flat roof, steep roof, building waterproofing and for tunnel waterproofing.

(16) It is preferable for the compositions according to the invention to be such that the organic polymer, the monomer from the group of acrylates and the catalyst from the group of tertiary organic amines are completely dissolved in the solvent.

(17) The production of the composition according to the invention occurs preferably by dissolving the polymer, the monomer from the group of acrylates and the catalyst from the group of tertiary organic amines in the solvent under stirring, preferably at approximately 80° C. for approximately 3 hours under reflux.

(18) The compositions according to the invention are particularly suitable for permanent bonding of polyolefinic membranes, called FPO or TPO (flexible polyolefin or thermoplastic polyolefin), with adhesives, wherein acrylate adhesives are particularly preferable. By pretreatment with these compositions, FPO membranes can be bonded to other FPO membranes or also to other substrates, on which the adhesive presents a good and lasting bonding. The non-FPO substrates, in the sense of the present invention, include in particular PVC membranes and rigid substrates (plastic, concrete and/or metal).

(19) Permanent bonding, in the context of the present invention, refers to a bonding which also has a high bond strength after natural or artificial aging.

(20) The composition according to the invention is characterized in particular in that it allows a bonding of polyolefinic substrates to other substrates that have a markedly high aging capacity.

(21) As adhesives for bonding the substrates after pretreatment of the polyolefinic substrates with the composition according to the invention, it is particularly suitable to use two-component acrylate adhesives, wherein tetrahydrofurfuryl methacrylate- or methyl methacrylate-based systems with peroxide initiation are particularly preferable. After the application of the composition according to the invention and drying with film formation, it is possible, for example, by using such two-component acrylate adhesives, to produce an adhesive bond which is characterized even after aging by unexpected high adhesive forces.

(22) In a particularly preferable embodiment, the composition according to the invention is designed so that the at least one organic polymer comprises at least one chlorinated polyolefin, which is based on hard or soft polypropylene, with a chlorination degree of 20 to 30%, and/or at least one maleic acid anhydride-modified polyolefin.

(23) Particularly good results are achieved if the at least one organic polymer comprises at least one or more polymers from the following:

(24) A hard polyolefin with a chlorination degree of 20-30% and a molecular weight of 150,000 g/mol (Poly1).

(25) A soft polyolefin with a chlorination degree of 20-30% and a molecular weight of 100,000 g/mol (Poly2).

(26) A hard polyolefin with a chlorination degree of 20-30%, a maleic acid anhydride content of 1 to 2% and a molecular weight of 60,000 g/mol (Poly3).

(27) A soft polyolefin with a chlorination degree of 20-30%, a maleic acid anhydride content of 1 to 2% and a molecular weight of 65,000 g/mol (Poly4).

(28) The compositions according to the invention moreover comprise at least one monomer from the group of acrylates. While generally all the monomers from the group of acrylates are suitable, it has been shown that particularly good results are achieved if the at least one monomer from the group of acrylates comprises an acrylate ester and/or a methacrylate ester, particularly in the form of one or more from methyl methacrylate, butyl methacrylate and lauryl methacrylate.

(29) Moreover, the compositions according to the invention comprise at least one catalyst from the group of tertiary organic amines. Aromatic tertiary amines have been shown to be particularly suitable.

(30) Examples of suitable tertiary aromatic amines are, in particular, tertiary aromatic amines selected from the group consisting of: N,N-dimethylaniline, N,N-diethylaniline, N,N-bis(hydroxyalkyl)aniline such as N,N-bis(2-hydroxyethyl)aniline, N,N-alkylhydroxyalkylaniline such as N-ethyl-N-hydroxyethylaniline, N,N-dimethyl-p-toluidine, N,N-diethyl-p-toluidine, N-methyl-N-hydroxyethyl-p-toluidine, N,N-bis(2-hydroxyethyl)-p-toluidine as well as alkoxylated N,N-bis-(hydroxyethyl)-p-toluidine, N-ethoxylated p-toluidine, N,N-bis(2-hydroxyethyl)-xylidine, N-alkylmorpholine and mixtures thereof.

(31) In a particularly preferable embodiment, the composition according to the invention is designed so that the at least one catalyst from the group of tertiary organic amines comprises N,N-bis-(2-hydroxyethyl)-para-tolui dine (“BISOMER® PTE”).

(32) In a particularly preferable embodiment, the at least one solvent is an organic solvent, wherein solvents from the group of aromatic solvents, in particular alkyl aromatic compounds, are particularly preferable. It has been shown that particularly good results are achieved if xylene is used as solvent.

(33) It is particularly preferable for the compositions according to the invention to be such that all the components are dissolved in the solvent.

(34) Particularly good results are achieved if the composition according to the invention is designed so that the individual components are in a ratio by weight such that the adhesion promoter composition comprises: approximately 1 to 10 parts by weight, in particular approximately 4 to 7 parts by weight of at least one organic polymer approximately 3 to 20, in particular approximately 10 to 15 parts by weight of at least one monomer from the group of acrylates approximately 3 to 16, in particular approximately 5 to 10 parts by weight of at least one catalyst from the group of tertiary organic amines approximately 54 to 93 parts by weight, in particular approximately 68 to 87 parts by weight of at least one solvent.

(35) It has been shown that the compositions according to the invention, after application and drying on apolar surfaces, surprisingly act as adhesive. Here, the inventors suspect that it is precisely the combination of a (non-reactive) polymer with a monomer from the group of (reactive) acrylates that, in cooperation with the other components, namely solvent and catalyst, leads to the surprisingly good action as adhesive. This principle is illustrated diagrammatically in FIG. 1.

(36) Another subject matter of the present invention is the use of the composition according to the invention for treating the surface of a polyolefinic substrate. As a result of this treatment, which occurs preferably by application by brushing onto or spraying of the surface of the polyolefinic substrate to be treated and subsequent drying of the treated site, the surface of the substrate to be treated is activated so that, in a subsequent step, for example, by use of an acrylate adhesive, a permanent bonding of the thus treated surface to another substrate is possible.

(37) An additional subject matter of the present invention is a method for the surface treatment of a polyolefinic substrate. The method according to the invention is designed so that a composition according to the invention is applied to the surface of a polyolefinic substrate and subsequently dried.

(38) In a preferred embodiment of the method according to the invention, after drying of the applied composition, an adhesive is applied to the site thus pretreated, and the polyolefinic substrate is subsequently bonded to another substrate. For the bonding of the pretreated polyolefinic substrate, it is preferable to use an acrylic adhesive, in particular in the form of a two-component acrylate adhesive, wherein it is preferable to use tetrahydrofurfuryl methacrylate- or methyl methacrylate-based systems with peroxide initiation.

(39) In a particularly preferred embodiment of the method according to the invention, the polyolefinic substrate is a waterproofing membrane, in particular from the field of flat roof waterproofing, steep roof waterproofing, building waterproofing and/or tunnel waterproofing, wherein bonding to a thermoplastic olefin membrane, to a PVC membrane, to a metallic substrate or to a concrete substrate, for example, occurs.

(40) The teaching according to the invention will now be explained in further detail in the following examples.

EXAMPLES

Example 1

Determination of the Peel Force in the Pretreatment with the Composition According to the Invention as a Function of the Polymer Content of the Composition

(41) A composition for pretreating polyolefinic substrates was produced with the following components:

(42) TABLE-US-00001 Polymer mixture Poly1, Poly2, Poly3 and Poly4 (see above) Monomer component Butyl methacrylate Catalyst BISOMER® PTE Solvent Xylene

(43) From the mentioned components, a composition according to the invention was prepared, wherein the following quantitative proportions were used:

(44) TABLE-US-00002 Polymer component 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10% by weight Monomer component 10% by weight Catalyst  6% by weight Solvent 84, 83, 82, 81, 80, 79, 78, 77, 76, 75 and 74% by weight

(45) By varying the percentage by weight of the polymer component from 0 to 10% by weight, it was possible to carry out an optimization of the polymer content.

(46) For this purpose, the substrate SARNAFIL® FPO Roofing Membrane (a thermoplastic roofing membrane) was pretreated with the compositions according to the invention and, after drying for 30 minutes, bonded using the adhesive SIKAFAST®-5221 (a reactive 2-component acrylic adhesive) to the substrate SARNAFIL® FPO Roofing Membrane.

(47) After curing the adhesive composition for 4 hours at 23° C., the peel force of the adhesive bond was determined for the compositions with the different polymer contents.

(48) The results for the different polymer contents are listed in Table 1.

(49) TABLE-US-00003 TABLE 1 Concentration [%] Peel force [N/5 cm] 0 1 1 18 2 21.5 3 54 4 75 5 75 6 75 7 61.5 8 52

(50) The results reproduced in Table 1 are represented graphically in FIG. 2.

Example 2

Determination of the Peel Force in the Pretreatment with the Composition According to the Invention as a Function of the Monomer Content of the Composition

(51) A composition for pretreating polyolefinic substrates was produced with the following components:

(52) TABLE-US-00004 Polymer mixture Poly1, Poly2, Poly3 and Poly4 (see above) Monomer component Butyl methacrylate Catalyst BISOMER® PTE Solvent Xylene

(53) From the mentioned components, a composition according to the invention was produced, wherein the following quantitative proportions were used:

(54) TABLE-US-00005 Polymer component 6% by weight (for each polymer 1.5% by weight) Monomer component 0, 3, 6, 12, 20% by weight Catalyst 6% by weight Solvent 88, 85, 82, 76 and 68% by weight

(55) By varying the percentage by weight of the monomer component from 0 to 20% by weight, an optimization of the monomer content was successfully carried out.

(56) For this purpose, the substrate SARNAFIL® FPO Roofing Membrane was pretreated with the composition according to the invention and, after drying for 30 minutes, bonded using the adhesive SIKAFAST®-5221 to the substrate SARNAFIL® FPO Roofing Membrane.

(57) After curing the adhesive composition for 4 hours at 23° C., the peel force of the adhesive bond for the compositions with different monomer contents was determined.

(58) The results for the different monomer contents are listed in Table 2.

(59) TABLE-US-00006 TABLE 2 Concentration [%] Peel force [N/5 cm] 0 127 3 130 6 140 12 198 20 147

(60) The results indicated in Table 2 are graphically represented in FIG. 3.

Example 3

Determination of the Peel Force in the Pretreatment with the Composition According to the Invention as a Function of the Catalyst Content of the Composition

(61) A composition for pretreating polyolefinic substrates was produced with the following components:

(62) TABLE-US-00007 Polymer mixture Poly1, Poly2, Poly3 and Poly4 (see above) Monomer component Butyl methacrylate Catalyst BISOMER® PTE Solvent Xylene

(63) From the mentioned components, a composition according to the invention was produced, wherein the following quantitative proportions were used:

(64) TABLE-US-00008 Polymer component  6% by weight (for each polymer 1.5% by weight) Monomer component 10% by weight Catalyst 0, 3, 6, 12% by weight Solvent 84, 81, 78 and 72% by weight

(65) By varying the percentage by weight of the catalyst component from 0 to 12% by weight an optimization of the catalyst content was successfully carried out.

(66) For this purpose, the substrate SARNAFIL® FPO Roofing Membrane was pretreated with the composition according to the invention and, after drying for 30 minutes, bonded using the adhesive SIKAFAST®-5221 to the substrate SARNAFIL® FPO Roofing Membrane.

(67) After curing the adhesive bond for 4 hours at 23° C., the peel force of the adhesive bond for the compositions with the different polymer contents was determined.

(68) The results for the different catalyst contents are listed in Table 3.

(69) TABLE-US-00009 TABLE 3 Concentration [%] Peel force [N/5 cm] 0 86 3 93 6 135 12 121

(70) The results reproduced in Table 3 are represented graphically in FIG. 4.

Example 4

Comparison of the Composition According to the Invention to Compositions from the Prior Art

(71) For the comparison test, a composition according to the invention was used, which contained the following components in the following weight ratios:

(72) TABLE-US-00010 Polymer component  6% by weight (for each polymer 1.5% by weight) Monomer component 10% by weight Catalyst  6% by weight Solvent 78% by weight

(73) For the comparison tests, a TPO substrate was pretreated with the composition according to the invention and, after drying for 30 minutes, bonded using the adhesive SIKAFAST®-5221 to a TPO substrate.

(74) After curing the adhesive bond for 4 hours at 23° C., the peel force of the adhesive bond was determined. Moreover, the peel force after aging in water for 28 days at 70° C. was determined. The same tests were also carried out with the pretreatment compositions known from the prior art. The result is shown in Table 4.

(75) TABLE-US-00011 TABLE 4 Examples for the aging (4 weeks 70° C. warm water): TPO-TPO bonding Peel Force [N/5 cm] Primer Initial After aging ROWA Primer: TRAPYLEN® 187 EAC (a solvent- 60 0 based solution of a chlorinated polyolefin 5% polymer (Toyobo HARDLEN® F-2P; an 80 0 adhesion promoter resin grafted with chlorine and/or maleic anhydride) dissolved in THF + xylene (50:50) 5% polymer (Toyobo HARDLEN® 16-LP; an 60 0 adhesion promoter resin grafted with chlorine and/or maleic anhydride) dissolved in THF + xylene (50:50) Composition according to the invention 135 140

(76) For an additional comparison example, a TPO substrate was pretreated with the composition according to the invention and, after drying for 30 minutes, bonded using the adhesive SIKAFAST®-5221) to a PVC substrate.

(77) After curing of the adhesive bond for 4 hours at 23° C., the peel force of the adhesive bond was determined. Moreover, the peel force after aging in water for 28 days at 70° C. was determined. The same tests were also carried out with pretreatment compositions known from the prior art. The result is shown in Table 5.

(78) TABLE-US-00012 TABLE 5 TPO-PVC bonding Peel Force [N/5 cm] Primer Initial After aging ROWA Primer: TRAPYLEN® 187 EAC 11 0 5% polymer (Toyobo HARDLEN® F-2P) dissolved in 12 0 THF + xylene (50:50) 5% polymer (Toyobo HARDLEN® 16-LP) dissolved 15 0 in THF + xylene (50:50) Composition according to the invention 140 200