Reactive cold-applied thermoplastic adhesive layer

Abstract

The present disclosure relates to a reactive cold-applied thermoplastic binder system and a method of applying the same. The system is a two-component or three-component system defined by one or more acrylate-based components and an initiator suspension. After mixing the components on-site at the construction site, the mixture is applied to a substrate (such as a waterproof membrane), and a road surface material (such as asphalt) is applied to the binder layer. Excellent asphalt compaction is observed, resulting in a high surface contact area and very little water penetrating into the binder layer interface. The high surface contact area and the penetration of asphalt into the binder layer provide good adhesion between the asphalt and the substrate.

Description

Field of the Invention

[0001] The present invention relates to the field of bond coats, and more particularly to cold-applied and reactive thermoplastic bond coats, especially in bridge deck waterproofing applications. BACKGROUND OF THE INVENTION

[0003] Bond coats are known and can be an essential part of a waterproofing system. See Figure 1 . Their main purpose is to provide adhesion and assist in compacting asphalt / concrete pavements to the waterproof membrane. Types of bond coats include asphalt-based hot melts, solvent-based acrylic bond coats, asphalt emulsions, and cold-applied reactive bond coats. A key property of any bond coat is to exhibit thermoplastic properties; the bond coat must melt upon thermal activation (by applying asphalt thereto at ~100 - 180 °C) to form a strong bond with the pavement material. Conventional cold-applied reactive materials do not melt if heated to typical asphalt application temperatures (or higher).

[0004] Hot-melt asphalt-based material. These types of bond coats mainly consist of asphalt or polymer-modified bitumen (PMB), which are supplied in solid form at room temperature. On-site, boilers are used to melt the asphalt at high temperatures (~120 - 190 °C), and then the molten material is applied to the waterproof membrane. This is an undesirable method due to the high energy requirements on-site, the risks associated with manually handling molten liquids, and the potentially toxic fumes emitted during application. In addition, such asphalt-based materials typically exhibit poor adhesion to typical membranes, especially polyurethane and polyurea, and must be fully over-scattered with aggregate on such membranes to provide a key between the membrane and the asphalt bond coat in order to achieve suitable adhesion. Furthermore, it has been observed that PMB debonds from the membrane at high ambient temperatures, so that "pick-up" occurs on the wheels, tracks, or tires of pavers / haul vehicles. Importantly, when testing the adhesion between the membrane and asphalt at high temperatures (>30 °C), it is found that the asphalt softens, resulting in poor adhesion values.

[0005] Solvent-based acrylic adhesive layer. Solvent - based acrylic binder layers are typically only suitable for bitumen - rich tars with low void content, such as mastic asphalt or sand carpet. Such binder layers typically contain high concentrations (>50%) of harmful solvents, which flash off when applied to the waterproof membrane to leave a thin film of dry thermoplastic material. The low limits on wet (and thus dry) application rates result in poor overall performance under many tar mix designs, especially those with low bitumen and higher void contents. Further problems can occur if any solvent remains trapped in the coating (which can cause softening and blistering of the tar).

[0006] Asphalt emulsion . Bitumen emulsions are stabilized dispersions of bitumen in water to allow application at ambient temperature (although many are still heated to ∼80°C). Application is restricted by ambient temperature (above 5°C). Long drying times are observed, especially at low ambient temperatures and high humidity (>70%). Typically, only low application rates of the dry material are possible (<0.3 kg / m 2 ). The low limits on dry application rates result in poor overall performance under many tar mix designs, especially those with low bitumen and higher void contents.

[0007] Cold-applied reactive adhesive layer . As the name implies, these materials can be applied at ambient temperature to eliminate the above - mentioned problems associated with having to heat and apply molten materials. Cold - applied reactive binder layers contain solvent - free liquid resins, which are catalytically cured in - situ immediately prior to application to form a solid coating. To date, only one such product has been commercialized to the knowledge of the present inventors, namely, sold by the current applicant GCP APPLIED TECHNOLOGIES INC under the trade name BOND COAT 3. However, improved adhesion properties and excellent thermoplastic properties are needed. Although having excellent performance for some tars, a more robust solution is needed to provide better binder layer performance over a wider range of tar mix designs.

[0008] Accordingly, what is needed is an excellent reactive cold - applied thermoplastic material that can be used for a wide range of pavement types (such as tar mix designs) to provide strong adhesion and contribute to the compaction of the pavement to the waterproof membrane. In fact, the importance of sufficient bond strength and avoiding interconnected voids at the interface is emphasized in the Highways England Design Manual for Roads and Bridges (Document CD358, Sections 6.4, 8.8, 8.8.1). However, given the prior art as a whole considered at the time the present invention was made, it was not obvious to the person of ordinary skill in the art of the present invention how to overcome the disadvantages of the prior art.

[0009] Although certain aspects of conventional techniques have been discussed to facilitate the disclosure of the present invention, the applicant in no way disclaims rights to these technical aspects and contemplates that the claimed invention may include one or more of the conventional technical aspects discussed herein.

[0010] The present invention can solve one or more problems and deficiencies of the above-mentioned prior art. However, it is expected that the present invention may prove useful in solving other problems and deficiencies in many technical fields. Therefore, the claimed invention is not necessarily to be construed as limited to solving any particular problem or deficiency discussed herein.

[0011] In this specification, where a document, regulation, or item of knowledge is mentioned or discussed, such mention or discussion does not admit that the document, regulation, or item of knowledge or any combination thereof was publicly available, was known to the public, was part of common general knowledge, or otherwise constituted prior art under the applicable law provisions on the priority date; or was known in connection with an attempt to solve any problem addressed in this specification. SUMMARY OF THE INVENTION

[0013] There is now provided a new, useful, and non-obvious invention that meets a long-standing but hitherto unmet need for improved compositions and methods for cold-applied, truly thermoplastic adhesive layers.

[0014] Exemplary embodiments of the present invention are compositions and methods for a 100% solids reactive cold-applied adhesive layer that exhibits truly thermoplastic properties upon curing. The adhesive layer comprises a first acrylate-based component that includes a tackifier, a plasticizer, and a promoter; a second component that includes an initiator suspension; and an optional third acrylate-based component that includes a tackifier and a plasticizer. In certain embodiments, the adhesive layer cures in a short time to form a solid coating that in turn melts when exposed to a temperature above its melting point. The molten adhesive layer promotes asphalt compaction at the film interface, thereby increasing the surface contact area between the asphalt and the film. It also allows aggregates to penetrate from the asphalt into the adhesive layer. The larger surface contact area means a larger adhesive surface area, resulting in higher tensile and shear adhesion values. The larger surface contact area corresponds to fewer voids at the film interface, limiting the area where water can penetrate to the interface via interconnected voids.

[0015] As the present disclosure continues, these and other important objects, advantages, and features of the present invention will become apparent.

[0016] The present invention thus includes the features of the construction, combinations of elements, and arrangements of components illustrated in the disclosure set forth below, and the scope of the present invention will be indicated in the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] To more fully understand the present invention, reference should be made to the following detailed description in conjunction with the accompanying drawings, in which:

[0019] Figure 1 is a cross-sectional schematic view of a waterproof structure for a bridge deck slab, including a base, a primer, one or more waterproof membranes, an adhesive layer, and a pavement surfacing. This schematic view is not drawn to scale (for example, the waterproof membrane is typically much thicker than the primer).

[0020] Figure 2A is a cross-sectional schematic view of a pavement surfacing (such as asphalt) applied to a conventional (non-PMB type) adhesive layer, where low compaction can be observed at the interface between the adhesive layer and the pavement surfacing. The voids at the interface result in a low contact area between the asphalt and the adhesive layer. Water can penetrate and accumulate in the voids in the asphalt. If the voids at the interface are interconnected, hydrostatic pressure can cause premature pavement failure.

[0021] Figure 2B is a cross-sectional schematic view of a pavement surfacing (such as asphalt) applied to an adhesive layer according to certain embodiments of the present invention, where high compaction and no voids can be observed at the interface between the adhesive layer and the pavement surfacing. Additionally, it can be seen that the asphalt penetrates into the molten adhesive layer, and the adhesive layer is displaced to further fill the voids at the interface.

[0022] Figure 3 is a graphical illustration comparing the viscosities (at various temperatures) of a polymer-modified asphalt type thermoplastic adhesive layer (SA1030) and an embodiment of this reactive thermoplastic adhesive layer (BC 4). The viscosity is measured by placing the material on a heated metal base (such as a Peltier plate) and moving a parallel plate down onto the material (a 1000-μm gap between the base and the plate). The device measures the viscosity of the material by rotating the parallel plate at a specific shear rate (1 revolution per second) and measuring the resistance.

[0023] Figure 4 is a series of schematic views that illustrate the percentage of water penetration through asphalt compacted on an adhesive layer, at the following levels: less than about 1% water penetration, about 50% water penetration, and about 100%. There is an indirect relationship between water penetration and the surface contact area between the asphalt / adhesive layer, such that a higher surface contact area results in lower water penetration.

[0024] DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0025] In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part thereof, and in which specific embodiments that can be used to practice the present invention are shown by way of example. It is to be understood that other embodiments may be employed and structural changes may be made without departing from the scope of the present invention.

[0026] As used in this specification and the appended claims, unless the context clearly dictates otherwise, the singular forms "a", "an", and "the" include plural referents. As used in this specification and the appended claims, unless the context clearly dictates otherwise, the term "or" is generally used in its sense including "and / or".

[0027] As used herein, "about" means approximate or close and, in the context of the recited numerical value or range, means ±15% of that numerical value. In exemplary embodiments, the term "about" may include conventional rounding according to the significant digits of the numerical value. Additionally, the phrase "about 'x' to 'y'" includes "about 'x' to about 'y'".

[0028] Furthermore, any numerical range recited in the specification or claims, such as a numerical range representing a particular set of properties, units of measurement, conditions, physical states, or percentages, is intended to literally and expressly include, by reference or otherwise, any numerical value falling within that range, including any sub-range of the numerical values so recited. For example, so long as a numerical range with a lower limit RL and an upper limit RU is disclosed, any numerical value R falling within that range is specifically disclosed. In particular, the following numerical values R within that range are specifically disclosed: R = RL + k(RU - RL), where k is a variable in increments of 1% from 1% to 100%, e.g., k is 1%, 2%, 3%, 4%, 5%....50%, 51%, 52%...95%, 96%, 97%, 98%, 99% or 100%. Additionally, any numerical range represented by any two R values calculated as above is also specifically disclosed.

[0029] In a first exemplary embodiment, the present invention is a reactive cold-applied thermoplastic adhesive layer system comprising:

[0030] A first component, which comprises:

[0031] A polyacrylate (e.g., poly(methyl methacrylate) (PMMA)) polymer, preferably in an amount of about 10 - 30 wt% of the composition,

[0032] An acrylate monomer, preferably in an amount of about 5 - 45 wt% of the composition,

[0033] A tackifier, preferably in an amount of about 10 - 50 wt% of the composition,

[0034] A plasticizer, preferably in an amount of about 0.1 - 10 wt% of the composition, and

[0035] A promoter, preferably in an amount of about 0 - 5 wt% of the composition;

[0036] A second component, which comprises an initiator suspension, such as a peroxide initiator suspension, in an amount of about 0-10% by weight of the composition; and

[0037] Optionally, a third component, which comprises:

[0038] A polyacrylate (e.g., PMMA) polymer, preferably in an amount of about 10-30% by weight of the composition;

[0039] An acrylate monomer, preferably in an amount of about 5-45% by weight of the composition;

[0040] A tackifier, preferably in an amount of about 10-50% by weight of the composition; and

[0041] A plasticizer, preferably in an amount of about 0.1-10% by weight of the composition;

[0042] Wherein the mixture of the first component, the second component and the optional third component is sprayable and curable to form a solid coating.

[0043] In a second exemplary embodiment that can be based on the first exemplary embodiment above, the first component further comprises at least one additive, preferably in an amount of about 0-50% by weight of the composition. In one aspect of this second exemplary embodiment, the at least one additive can be selected from fillers, inhibitors, pigments, anti-settling aids, rheology modifiers, photoinitiators, UV stabilizers, degassing agents, antistatic agents, accelerators, catalysts, stabilizers, flame retardants, pH regulators, reinforcing agents, thickeners or diluents, elastic compounds, chain transfer agents, radiation absorbing compounds, radiation reflecting compounds, and combinations thereof.

[0044] In a third exemplary embodiment that can be based on any one of the first to second exemplary embodiments above, the second component is mixed with the third component (in the case where the third component is included) to form an activated third component, wherein the mixture of the first component and this activated third component is sprayable and curable to form an adhesive layer. In one aspect of this third exemplary embodiment, the third component further comprises at least one additive, preferably in an amount of about 0-50% by weight of the composition. Optionally, the at least one additive is selected from fillers, inhibitors, pigments, anti-settling aids, rheology modifiers, photoinitiators, UV stabilizers, degassing agents, antistatic agents, accelerators, catalysts, stabilizers, flame retardants, pH regulators, reinforcing agents, thickeners or diluents, elastic compounds, chain transfer agents, radiation absorbing compounds, radiation reflecting compounds, and combinations thereof.

[0045] In a fourth exemplary embodiment that can be based on any one of the first to third exemplary embodiments above, the bonding layer - after curing and when exposed to a temperature of about 200 °C or lower - becomes a molten liquid, the viscosity of which effectively aids in the compaction of the pavement material applied to the bonding layer, so that the water permeability at the interface between the bonding layer and the pavement material is about 50% or less, preferably about 1% or less. In one aspect of this fourth exemplary embodiment, the exposure temperature is about 100 °C or lower, and the viscosity is about 6000 cP or lower.

[0046] In a fifth exemplary embodiment that can be based on any one of the first to fourth exemplary embodiments above, the bonding layer results in a shear adhesion between the substrate (such as a waterproof membrane) on which the bonding layer is applied and the pavement material applied to the bonding layer of about 0.3 MPa to about 3.0 MPa at a temperature of about 23 °C and a coating amount of about 600 - 1200 gsm.

[0047] In a sixth exemplary embodiment that can be based on any one of the first to fifth exemplary embodiments above, the bonding layer results in a tensile adhesion between the substrate and the pavement material of about 0.3 MPa to about 1.3 MPa at a temperature of about 23 °C and a coating amount of about 600 - 1200 gsm.

[0048] In a seventh embodiment that can be based on any one of the first to sixth embodiments, the present invention is a method of bonding a pavement material to a substrate, which includes:

[0049] Mixing a first component and a second component together;

[0050] Wherein the first component comprises:

[0051] A polyacrylate (such as PMMA) polymer, preferably in an amount of about 10 - 30% by weight of the composition,

[0052] An acrylate monomer, preferably in an amount of about 5 - 45% by weight of the composition,

[0053] A tackifier, preferably in an amount of about 10 - 50% by weight of the composition,

[0054] A plasticizer, preferably in an amount of about 0.1 - 10% by weight of the composition, and

[0055] A promoter, preferably in an amount of about 0 - 5% by weight of the composition;

[0056] Wherein the second component comprises an initiator suspension, such as a peroxide initiator suspension, in an amount of about 0 - 10% by weight of the composition;

[0057] Applying the mixture to the substrate without using a heating element;

[0058] Cure the mixture to form a cured bonding layer;

[0059] Apply a road surface material onto the cured bonding layer to form a composite material of the road surface material, the bonding layer, and the membrane (substrate).

[0060] In an eighth embodiment that can be based on any one of the fifth to seventh embodiments, the road surface material is bitumen. In one aspect of such an eighth embodiment, the bitumen can be selected from asphaltic concrete, hot rolled asphalt, stone mastic asphalt, mastic asphalt, porous asphalt, sand felt, asphalt protection layer, or a combination thereof. In another aspect of such an eighth embodiment, the bitumen can have an average aggregate size of up to about 55 mm.

[0061] In a ninth embodiment that can be based on any one of the seventh to eighth embodiments, the substrate is a waterproof membrane.

[0062] In a tenth embodiment that can be based on any one of the seventh to ninth embodiments, the step of applying the mixture onto the substrate is carried out by spraying the mixture onto the substrate.

[0063] In an eleventh embodiment that can be based on any one of the seventh to tenth embodiments, the mixture is applied onto the substrate at a coating amount of about 100 gsm to about 1400 gsm.

[0064] In a twelfth embodiment that can be based on any one of the first to eleventh embodiments, the method further includes mixing a third component with the second component to form an activated third component, which is then mixed with the first component and applied onto the substrate.

[0065] In a thirteenth embodiment that can be based on any one of the fifth to twelfth embodiments, after applying the road surface material onto the cured bonding layer, the road surface material can be compacted on the bonding layer so that the water permeability at the interface between the bonding layer and the road surface material is about 50% or less, preferably about 1% or less.

[0066] In a fourteenth exemplary embodiment that can be based on any one of the seventh to thirteenth exemplary embodiments described above, the adhesive layer - after curing and when exposed to a temperature of about 200 °C or lower - becomes a molten liquid, the viscosity of which effectively aids in the compaction of the pavement material applied on the adhesive layer, such that the water permeability at the interface between the adhesive layer and the pavement material is about 50% or less, preferably about 1% or less. In one aspect of such a fourteenth exemplary embodiment, the exposure temperature is about 100 °C or lower, and the viscosity is about 6000 cP or lower.

[0067] In a fifteenth exemplary embodiment that can be based on any one of the seventh to fourteenth exemplary embodiments described above, the adhesive layer results in a shear adhesion between the substrate and the pavement material of about 0.3 MPa to about 3.0 MPa at a temperature of about 23 °C and an application amount of about 600 - 1200 gsm.

[0068] In a sixteenth exemplary embodiment that can be based on any one of the seventh to fifteenth exemplary embodiments described above, the adhesive layer results in a tensile adhesion between the substrate and the pavement material of about 0.3 MPa to about 1.3 MPa at a temperature of about 23 °C and an application amount of about 600 - 1200 gsm.

[0069] In a seventeenth exemplary embodiment, the present invention is a reactive cold-applied thermoplastic adhesive layer system based on any one or more or even all of the first to sixth exemplary embodiments.

[0070] In an eighteenth exemplary embodiment, the present invention is a method of bonding a pavement material to a substrate based on any one or more or even all of the seventh to sixteenth exemplary embodiments.

[0071] In certain exemplary embodiments, the present invention teaches a liquid composition having excellent thermoplastic properties and that can be sprayed to various application amounts depending on the type of asphalt used. The resin has a wide application temperature range and can be cold-applied using a standard 1:1 ratio pump. Once applied, the system cures seamlessly to provide strong adhesion to the waterproof membrane. When hot asphalt is applied, the cured adhesive layer melts and becomes highly fluid, promoting stronger compaction of the asphalt at the membrane interface. This results in a higher surface contact area between the asphalt and the membrane, as well as a reduction in air voids at the interface. The system has a curing time of within two (2) hours, preferably within one (1) hour, at -10 to 50 °C, is a 100% solids content reactive system, and has a low volatile organic compound (VOC) content. The tensile and shear adhesion values of the asphalt to the membrane are found to be surprisingly excellent, even when tested at high temperatures (50 °C). In certain embodiments, the composition is particularly useful for waterproof membranes and can be applied under normal conditions that can be withstood on concrete and steel bridge decks.

[0072] In the present disclosure, the term "cold applied" refers to the ability of a composition to be applied at ambient temperature without the use of a melting boiler or heating line prior to application. Due to the high energy requirements on site, the risks associated with handling molten liquids manually, and the potential toxic fumes emitted during application, the use of a boiler or other heating device is undesirable. Instead, embodiments of the present adhesive layer composition can be applied in the ambient temperature range (e.g., from about -10°C to about 50°C) without any heating requirements.

[0073] In the present disclosure, the term "compaction" refers to the process of densifying hot mix asphalt by reducing the voids within the asphalt, thereby promoting a higher surface contact area between the pavement material and the waterproof membrane. Well-compacted asphalt is characterized by low water penetration at the interface due to the lack of interconnected voids within the asphalt. Asphalt mixtures are designed to have different void contents after proper compaction. This typically varies between about 1% (e.g., mastic asphalt) to about 20% (e.g., porous asphalt). Compaction is typically achieved by applying an external force (rollers) on the asphalt mixture. Good compaction is typically most difficult to achieve at the bottom of the asphalt layer where it contacts the underlying solid substrate. The importance of minimizing / eliminating air voids at the interface is a well-established requirement for minimizing the risk of premature failure of asphalt pavements. Highways England Design Manual for Roads and Bridges (Document CD358) provides guidance on the type and thickness of asphalt to be used directly on the waterproof membrane. CD358 states that the air void content in the asphalt layer directly above the waterproof membrane should be less than 4%, so the amount of water entering the layer is low. It further states that the interconnection of voids at the bottom of the asphalt layer should be prevented - this can be achieved by using a suitable adhesive layer. Embodiments of the present adhesive layer are envisioned to achieve better compaction at the interface compared to conventional adhesive layers (non-PMB type) due to the thermoplastic nature of the present composition. A fully molten adhesive layer promotes significantly better compaction compared to a conventional cold applied reactive adhesive layer. Better compaction at the interface results in a larger surface contact area between the asphalt and the adhesive layer, leading to higher adhesion. In addition, the present adhesive layer allows the asphalt to penetrate into and embed within the adhesive layer to create a strong mechanical bond. At the same time, the molten adhesive layer shifts upwards to fill any remaining voids at the interface. For a comparison of low compaction (as seen in conventional non-PMB adhesive layers) versus high compaction (as seen in the present adhesive layer), see Figures 2A - 2B.

[0074] In the present disclosure, the term "thermoplastic" refers to the property of a material that melts when heated above its melting temperature and solidifies when cooled below its melting temperature. Thermoplastic materials are different from thermosetting materials, which irreversibly become solid after curing. Certain embodiments of the present invention are unique in that they cure to become solid and thereafter behave as true thermoplastic materials, i.e., cold-applied liquid materials that melt when heated above the melting temperature.

[0075] Conventionally, cured methyl methacrylate-based cold-applied reactive coatings do not melt when subjected to high temperatures. Therefore, it was surprising when it was found that embodiments of the present invention (acrylate-based cold-applied reactive materials) have true thermoplastic properties at higher temperatures. Without being bound by theory, it is speculated that this phenomenon occurs due to the combination of rosin esters and plasticizers included in the composition and / or due to the lubricating nature of the plasticizer at the molecular level, thus enabling a lower density polymer network and / or causing the polymer network to expand significantly and become a molten liquid at high temperatures.

[0076] In the present disclosure, the term "water penetration" refers to the ability of water to penetrate through an asphalt mixture at the asphalt-film interface via interconnected voids. The water penetration at the interface is recorded as a percentage and can be determined by methods known in the art. In the present disclosure, the measurement value of the water penetration at the interface is obtained according to the following method. A complete composite sample (i.e., approximately 1 ft x 1 ft) is prepared, including the following layers: concrete, primer, film, bond coat, and asphalt. Once the sample is prepared, the sample is cut into test sample size (i.e., approximately 100 mm x 200 mm) using a concrete saw with a water pump (containing appropriately dyed water). The water is applied directly to the rotating saw at the cutting location. If there are any voids / no-contact areas at the interface between the asphalt and the film, the pressurized water will penetrate into such gaps and pass through the interface via interconnected voids. After removing the asphalt layer by a shear adhesion test (according to ETAG 033), the surface of the bond coat can be evaluated to determine whether water has penetrated any voids at the asphalt-film interface. This is a visual evaluation, in which the approximate surface area contaminated by the dyed water at the interface is reported. This is illustrated in Figure 4 where the water penetration rate is classified as approximately 100%, approximately 50%, or equal to or less than approximately 1%. Preferably, using the bond coat according to the present disclosure in the composite systems discussed herein results in a water penetration rate of approximately 90% or less, preferably approximately 50% or less, or even more preferably approximately 1% or less.

[0077] The thermoplastic binder layer enables more efficient compaction of the asphalt, thereby minimizing the voids at the interface. They can also flow into and fill such voids to further minimize the water entering the membrane interface. In one embodiment, the present invention is a reactive cold-applied thermoplastic binder layer composition, which comprises the following three components (A, B, C), which are mixed and sprayed on-site:

[0078] (1) Component A

[0079] a. Polyacrylate polymer, preferably in an amount of about 10-30% by weight of the composition;

[0080] b. Acrylate monomer, preferably in an amount of about 5-45% by weight of the composition;

[0081] c. Tackifier, preferably in an amount of about 10-50% by weight of the composition;

[0082] d. Plasticizer, preferably in an amount of about 0.1-10% by weight of the composition;

[0083] e. Optionally at least one additive, preferably in an amount of about 0-50% by weight of the composition; and

[0084] f. Promoter, preferably in an amount of about 0-5% by weight of the composition.

[0085] (2) Component B

[0086] a. Initiator suspension, such as peroxide initiator suspension, preferably in an amount of about 0-10% by weight of the composition.

[0087] (3) Component C

[0088] a. Polyacrylate polymer, preferably in an amount of about 10-30% by weight of the composition;

[0089] b. Acrylate monomer, preferably in an amount of about 5-45% by weight of the composition;

[0090] c. Tackifier, preferably in an amount of about 10-50% by weight of the composition;

[0091] d. Plasticizer, preferably in an amount of about 0.1-10% by weight of the composition; and

[0092] e. Optionally at least one additive, preferably in an amount of about 0-50% by weight of the composition.

[0093] In the present disclosure, the term "polyacrylate" refers to a synthetic resin formed by the polymerization of acrylates, where the resin serves as the polymeric backbone of the components. Plastics based on polyacrylates are typically characterized by their toughness and elasticity. Examples of polyacrylate polymers contemplated for use herein include, but are not limited to, polymethacrylate polymers (such as poly(methyl methacrylate) (PMMA) or poly(methyl methacrylate)-co-n-butyl methacrylate). It is envisioned herein that the polyacrylate polymers used herein can be synthesized from various acrylates or methacrylates and can be homopolymers or copolymers thereof, and / or any combination thereof. Further noted, an acrylate monomer is an ester containing a vinyl group directly attached to the carbonyl carbon of the ester group. An acrylate monomer has the structure H 2 C=C(R 1 )COOR 2 .

[0094] In the present disclosure, the term "tackifier" refers to a material that helps to melt the coating upon heating. It also helps to improve the tensile adhesion and shear strength between two different materials, such as between a film and a road surface via an adhesive layer. Examples of tackifiers contemplated for use herein include, but are not limited to, terpene phenols, styrenated terpenes, rosin esters, α-methylstyrene phenols, polyterpenes, or any combination thereof. The amount of tackifying resin used can be about 10 - 50 wt% of the composition in which the tackifier is present, preferably about 30 wt% of the composition.

[0095] In the present disclosure, the term "plasticizer" refers to a material that can be added to the adhesive layer composition to enhance the thermoplastic behavior of the cured material, i.e., a material that can cause it to completely melt when heated above its melting point. Examples of plasticizers contemplated for use herein include, but are not limited to, adipates, dibutyl sebacate, dibutyl maleate, diisobutyl maleate, phthalates, terephthalates, phthalic dicarboxylates, phthalic tricarboxylates, trimellitates, benzoates, and others, including diisononyl 1,2-cyclohexanedicarboxylate (DINCH), organophosphates, diols, polyethers, and bio-based plasticizers. In a preferred embodiment, a phthalate is used as the plasticizer. The amount of plasticizer used can be about 0.1 - 10 wt% of the composition in which the plasticizer is present, preferably about 2.0 - 8.0 wt% of the composition, and more preferably about 3 wt% of the composition.

[0096] In the present disclosure, the term "viscosity" refers to a measure of the resistance of a fluid to deformation (flow) at a given shear rate. Liquids with lower viscosities flow more freely / easily than liquids with higher viscosities. Viscosity is typically measured in centipoise (cP). The viscosity of a liquid, such as the adhesive layer composition, can be determined by methods known in the art. It should be noted that embodiments of the present invention can be liquids before and after curing; these two cases are defined as follows. The first case specifically represents the adhesive layer before curing, i.e., before the addition of an initiator. At this stage, the product is a free-flowing solution of a tackifier and other additives dissolved in a low-viscosity monomer, and radical polymerization has not been initiated. The addition of a radical initiator (e.g., benzoyl peroxide) initiates the radical polymerization reaction, which results in the formation of a solid polymer network. The second case is when this cured solid material is heated to a temperature above its melting point, at which point it becomes a flowable molten liquid. It can be understood that the second case demonstrates thermoplastic behavior because the material melts when heated to a temperature above its melting point; in contrast, a thermosetting material does not melt regardless of the elevated temperature. In the present disclosure, a cone-plate rheometer (TAINSTRUMENTS HR-1 DISCOVERY Hybrid Rheometer) is used to obtain viscosity measurements for this second molten case. The rheometer has 40-mm parallel plates, a 1000-μm gap, and Peltier plates for temperature control. The temperature is ramped down from 200°C to 80°C at a rate of 2°C per minute, and 30 viscosity measurements are recorded per minute. The plates are rotated at a shear rate of 1 reciprocal second (1 / s). Preferably, at a temperature of about 85°C or higher, the adhesive layer taught by the present disclosure has a viscosity of about 6000 cP or lower, 5800 cP or lower, 5600 cP or lower, 5400 cP or lower, 5200 cP or lower, 5000 cP or lower, 4800 cP or lower, 4600 cP or lower, or within the range between any two of these values.

[0097] It should be noted that certain embodiments of the present invention have a melting temperature of approximately 85 °C such that the cured adhesive layer becomes a molten liquid and can interact with the road surface material (such as hot asphalt) applied thereon, so that the road surface material can be better compacted onto the adhesive layer at the film interface, resulting in a higher surface contact area and thus an improved adhesion value. However, this melting point can be adjusted according to the composition of the adhesive layer so that it can be higher or lower as needed. Therefore, the temperature of 85 °C is used herein as a reference point for the embodiments of the present invention. In addition, the viscosity can also be adjusted based on the composition of the adhesive layer. The main consideration is that the molten viscosity of the adhesive layer is low enough to promote excellent compaction of the paving material, thereby providing a high surface contact area at the film interface, resulting in a low water permeability at the interface (preferably ≤ ~50%, more preferably ≤ ~1%). The second requirement is that the molten adhesive layer completely wets the paving material and achieves close contact to achieve a higher adhesion value.

[0098] In the present disclosure, the term "molten liquid" refers to a state of the adhesive layer having a viscosity low enough to allow interaction with the road surface material (such as hot asphalt), be able to penetrate into the road surface material (such as hot asphalt), wet the road surface material (such as hot asphalt), and promote compaction of the road surface material (such as hot asphalt), so that after curing to form a composite material that fixes the adhesive layer and the road surface material together, the surface contact area at the interface is high, which is manifested as a low water permeability at the interface (preferably ≤ 50% or more preferably ≤ 1%). It can be recognized that the melting point and molten viscosity of the adhesive layer can vary based on the composition while still being low enough to allow interaction with the road surface material, be penetrated by the road surface material, and compact the road surface material. The sufficient viscosity can depend on the nature of the road surface material. For example, it has been found that certain embodiments of the present invention have a viscosity of approximately 6000 cP or less measured at 85 °C. However, higher viscosities and melting points are envisioned as long as the cured adhesive layer can form a molten liquid that interacts with the road surface material to result in a higher surface contact area and low water permeability at the interface.

[0099] It should be noted that when asphalt is used as the road surface material applied to the adhesive layer, the maximum temperature of the adhesive layer after contact with hot asphalt is approximately 200 °C, or more specifically approximately 190 °C. Therefore, it is envisioned that the adhesive layer should have a melting point below approximately 200 °C so that when exposed to such a temperature, the adhesive layer melts and has a suitable viscosity to effectively promote compaction of the road surface material applied to the adhesive layer, such that the surface contact area at the interface between the adhesive layer and the road surface material is approximately 50% or greater (so that the water permeability is approximately 50% or less), more preferably approximately 99% or greater (so that the water permeability is approximately 1% or less). In certain embodiments, this exposure temperature is approximately 100 °C or lower, and the adhesive layer viscosity is approximately 6000 cP or lower (although higher viscosities are envisioned).

[0100] It can be seen that the embodiments of the present adhesive layer exhibit true thermoplastic properties compared to conventional non-melting reactive adhesive layers. Although conventional reactive adhesive layers can provide satisfactory performance under rich asphalt and low void mixture designs, they do not provide suitable performance for asphalt mixture designs with higher void contents (>4%), lower asphalt contents (<5%), and / or containing larger aggregates (>14 mm). In contrast, the adhesive layer of the present invention has a temperature vs. viscosity curve similar to that of conventional PMB asphalt-based thermoplastic adhesive layers that have long been proven to contribute to compaction and filling of voids at the film interface (but the present adhesive layer does not have the disadvantages of conventional asphalt-based thermoplastic adhesive layers). See Figure 3 . As also seen in Table 1, the present adhesive layer is fluid at all test temperatures, which supports the compaction process. Although the present adhesive layer does not have the fluidity of asphalt-based hot-melt thermoplastic adhesive layers, its fluidity is sufficient to provide excellent compaction - as confirmed by the fact that no water enters the adhesive layer - asphalt interface during testing of the cured samples, which will be further discussed hereinafter in this specification.

[0101]

[0102] *It should be noted that it is not possible to measure the viscosity of conventional reactive adhesive layers because they remain mainly solid at elevated temperatures - only a small fraction (~10%) of their mass actually melts, and most (~90%) remains solid.

[0103] Table 1. Viscosity comparison of a conventional hot-melt thermoplastic adhesive layer, a conventional reactive adhesive layer, and an embodiment of the present reactive thermoplastic adhesive layer

[0104] In the present disclosure, the term "promoter" refers to a compound or substance added to one of the components that is a precursor of the sprayable combined resin mixture. The promoter is a co-initiator used in the free radical polymerization of the combined resin mixture. Examples of promoters contemplated for use herein include, but are not limited to, dimethylaniline, dimethyl-p-toluidine, methylhydroxyethyl p-toluidine, and diisopropyltoluidine. In a preferred embodiment, toluidine is used as the promoter. Each of the foregoing promoters can affect the gel / cure time as needed. The amount of promoter used can be about 0 - 5 wt% of the composition in which the promoter is present, preferably about 1.5 - 4 wt% of the composition, and more preferably about 0.7 wt% of the composition. In addition to the promoter, an inhibitor can optionally be added to improve the storage stability, shelf life, and / or pot life of the reaction mixture.

[0105] In the present disclosure, the term "free radical initiator" refers to a compound or suspension or substance added to one of the components that is a precursor of the resulting adhesive layer mixture, where it generates free radical species and promotes free radical reactions when mixed with other suitable components. The concentration can vary depending on the ambient temperature. Examples of free radical initiators contemplated for use herein include, but are not limited to, sodium persulfate, potassium persulfate, ammonium persulfate, peroxide initiators, ferrous sulfate, and tert-butyl peroxide and mixtures thereof. In a preferred embodiment, a peroxide initiator suspension is used as the free radical initiator. The amount of free radical initiator used can be about 0 - 10 wt% of the composition, preferably about 2 - 8 wt%, and more preferably about 3 wt% of the composition.

[0106] Methodologically, certain embodiments of the present invention contemplate the use of the above three-component adhesive layer composition in waterproofing applications, such as on bridge decks. Components A, B, and C above are packaged and transported separately to the job site. At the site, component B is mixed with component C to form a so-called "activated component C". Then, components A and the activated component C are pumped via two feed manifolds to a mixing unit using a suitable airless spraying device at a 1:1 ratio, where components A and the activated component C are mixed. The mixed material is now fully activated and flows to a spray gun / nozzle, where the material is atomized / sprayed onto a waterproof membrane (or other substrate) at the desired thickness. The adhesive layer cures by free radical polymerization to provide a solid seamless coating.

[0107] When combining the above components, especially acrylate-based components, the resulting material is fluid and can be easily applied to a substrate (such as a waterproof membrane) in a suitable coating amount. The promoter, free radical initiator, and acrylate mixture form the basis of the reaction that leads to polymerization. This mixture is sprayed (or otherwise applied) onto the substrate before curing. Once fully cured, and when hot asphalt (≥85 °C) is applied, the adhesive layer melts, allowing the asphalt mixture to interact with and penetrate into the molten coating. This helps to improve compaction and a greater surface contact area at the membrane interface. Upon cooling, the adhesive layer re-cures, forming a permanent mechanical bond with the asphalt.

[0108] In an alternative embodiment of the present invention, the adhesive layer composition is a two-component system, where component C can be removed (or only optionally included) such that the composition contains components A and B and functions with components A and B. Components A and B are packaged and transported separately to the job site. At the site, component B is directly mixed with component A to form a reactive material. Then, the mixture is immediately applied to a waterproof membrane (or other substrate) using a jet pump (1 manifold or 98:2 system) or a manual device such as a squeegee or roller. The adhesive layer cures by free radical polymerization to provide a solid seamless coating.

[0109] More generally, using a bridge deck as an exemplary application, providing a base or surface of the bridge deck, applying a primer to the base of the bridge deck, applying one or more waterproof membranes to the primer, applying the adhesive layer composition of certain embodiments of the present invention to the waterproof membrane, and applying a road surface material to the adhesive layer composition.

[0110] In the present disclosure, the term "shear adhesion" refers to a measure of the adhesion strength between two different materials, such as between a waterproof membrane and asphalt, where the adhesive layer resists the shear force that causes the asphalt to slide away from the substrate / membrane. Shear adhesion is typically recorded in megapascals (MPa) and can be determined by methods known in the art. In the present disclosure, unless otherwise specified, shear adhesion measurements are obtained according to the ETAG 033 standard, in particular EN1 3653:2004. Preferably, the adhesive layer taught by the present disclosure has - at a coating weight of ~600 - 1200 gsm and a temperature of ~23°C - a shear adhesion of approximately 0.1 MPa to approximately 3.5 MPa, more preferably approximately 0.3 MPa to approximately 3.0 MPa, or even more preferably approximately 0.5 MPa to approximately 2.5 MPa. Additionally, the adhesive layer taught by the present disclosure has - at a coating weight of ~600 - 1200 gsm and a temperature of ~50°C - a shear adhesion of approximately 0.01 MPa to approximately 0.5 MPa, more preferably approximately 0.03 MPa to approximately 0.4 MPa, or even more preferably approximately 0.05 MPa to approximately 0.30 MPa. It is contemplated that for asphalt-based compositions (e.g., if a lower Pen / harder asphalt is used in the asphalt mixture design), the shear adhesion may be higher than those listed above.

[0111] In the present disclosure, the term "tensile adhesion" refers to a measure of the bond strength between two different materials, more specifically between a waterproof membrane and bitumen, where the bonding layer holds the materials together when a perpendicular tensile force is applied. Tensile adhesion is typically recorded in megapascals (MPa) and can be determined by methods known in the art. In the present disclosure, unless otherwise stated, tensile adhesion measurements are obtained according to the ETAG 033 standard, in particular EN16596. Preferably, the bonding layer taught by the present disclosure has a tensile adhesion of approximately 0.1 MPa to approximately 1.5 MPa, more preferably approximately 0.3 MPa to approximately 1.3 MPa, or even more preferably approximately 0.5 MPa to approximately 1.0 MPa - at a coating weight of ~600 - 1200 gsm and a temperature of ~23 °C. Additionally, the bonding layer taught by the present disclosure has a tensile adhesion of approximately 0.01 MPa to approximately 0.35 MPa, more preferably approximately 0.04 MPa to approximately 0.30 MPa, or even more preferably approximately 0.07 MPa to approximately 0.25 MPa - at a coating weight of ~600 - 1200 gsm and a temperature of ~50 °C. It is envisaged that, based on the bitumen composition (e.g., if a lower Pen / harder asphalt is used in the bitumen mix design), the tensile adhesion may be higher than those listed above.

[0112] It should be noted that although the present compositions and methods are generally most beneficial for the adhesion between waterproof membranes and various types of bitumen in bridge deck applications, other suitable pavement materials and applications are also envisaged herein. Specifically with respect to bitumen, certain embodiments of the present bonding layer can be designed for various types of bitumen, including but not limited to asphalt concrete (AC), hot rolled asphalt (HRA), stone mastic asphalt (SMA), mastic asphalt (MA), porous asphalt, and sand felt (e.g., asphalt wearing course). It should be noted that even within each class of bitumen, there is no fixed mix design, and significant variations in bitumen thickness and bitumen composition can be observed.

[0113] An exemplary embodiment of the present invention is a low VOC, 100% solids content, reactive cold-apply liquid coating system. The coating is capable of fully curing within two (2) hours, preferably one (1) hour, within a wide temperature range (approximately -10 °C to +50 °C). These properties minimize the process application time within a wide application temperature range. Certain embodiments of the present invention are unique in that they are cold-apply reactive materials but behave as thermoplastic materials. This feature provides significant utility as no longer is a hot boiler required to melt traditional thermoplastic materials (such as asphalt), yet the material retains thermoplastic properties after curing. An exemplary embodiment of the present coating is a cold-apply liquid to provide numerous advantages, including lower energy costs, carbon emissions, fumes entering the environment, and better bonding to the substrate / membrane.

[0114] In the present disclosure, the term "cure time" refers to the time required for a fully initiated composition to cure to a non-tacky surface. The cure time is recorded in any unit of time, such as seconds, minutes, or hours. In the present disclosure, unless otherwise stated, the cure time is obtained according to ASTM D5895 standard and / or otherwise recorded when the material is dry to limb contact. Preferably, the reactive thermoplastic adhesive layer compositions taught by the present disclosure have a cure time of about 3.0 hours or less, about 2.5 hours or less, about 2.0 hours or less, about 1.5 hours or less, about 1.0 hours or less, or within the range between any two of these values. More preferably, in the temperature range of about -10 to +50 °C, the cure time of the adhesive layer is about 2.0 hours or less, more particularly about 1.0 hours or less. It is contemplated that the lower limit of this range is about 1 minute, although this depends on the ambient temperature and the concentration of free radical initiators within the composition itself.

[0115] In a further embodiment, the formulation enables the fully cured material to be heat-activated / melted when any type of asphalt of ~85 °C or higher is applied thereto. When heat-activated, its thermoplastic properties are comparable to those of conventional hot melt PMB thermoplastic adhesive layers. It should be noted that these conventional hot melt PMB thermoplastic adhesive layers are heat-applied, for example, a boiler is required to melt for application, and poor adhesion to the film is observed - a drawback that is alleviated using certain embodiments of the present invention.

[0116] In certain embodiments, the adhesive layer can be sprayed at various coat weights (e.g., approximately 200, 300, 600, 1200, and / or 1400 gsm), depending on the application requirements. In the present disclosure, the term "coat weight" or "wet film thickness" refers to a measure of the amount of a coating, such as the adhesive layer, on a substrate, such as a waterproof membrane. Coat weight is typically recorded in grams per square meter (gsm). The coat weight of a material can be determined by methods known in the art. In the present disclosure, unless otherwise specified, a dip comb (ELCOMETER 112AL) is used to obtain coat weight measurements while the material is sprayed and remains liquid on the substrate (e.g., bridge deck) before curing. Before the liquid adhesive layer cures, the dip comb is pressed onto the liquid adhesive layer, which provides a thickness measurement for the applicator. The wet film thickness is related to the gsm by using density as a conversion factor. Preferably, the adhesive layer taught by the present disclosure can be applied at a coat weight of approximately 50 gsm or greater, 100 gsm or greater, 300 gsm or greater, 600 gsm or greater, 900 gsm or greater, 1200 gsm or greater, 1500 gsm or greater, 1800 gsm or greater, 2100 gsm or greater, or within a range between any two of these values. The upper limit range of such coat weight measurements can be approximately 2500 gsm, although the adhesive layer thickness ultimately depends on the asphalt mixture design and the asphalt thickness.

[0117] It should be noted that conventional bituminous emulsions are applied using heating lines and scrapers, resulting in inconsistent thicknesses due to the difficulty of control. Conventional PMB thermoplastic binder courses are also difficult to apply because they are typically spread using an applicator with a scraper; this application method not only results in inconsistent thicknesses similar to bituminous emulsions, but also has to be done very quickly due to the relatively small time window (when the bitumen is extremely hot and thus liquid). If the conventional bitumen thermoplastic binder course is applied too thick, "bleeding" can occur. When hot asphalt is applied to the binder course, the thicker areas can melt and "bleed" into the actual asphalt wearing course. This leaves little binder course at the interface, creating voids. This is a particular problem for applications carried out at high temperatures when the conventional PMB thermoplastic binder course is at its softest. This bleeding can be seen when the shear adhesion test is carried out at 60 °C in accordance with ETAG 033. When thick hot melt PMB is used at high temperatures, the shear test according to this standard also shows slippage of the asphalt layer - sometimes referred to as "fatigue". Conventional PMB thermoplastic binder courses are prone to peeling from the membrane at high temperatures during traffic, which poses a significant problem for contractors as traffic is an essential requirement on a busy construction site. In contrast, certain embodiments of the present invention have proven to adhere well to the membrane even at high temperatures, thereby eliminating any pick-up or peeling problems. This characteristic is seen when the ETAG 033 tensile adhesion test is carried out from approximately 10 °C to approximately 50 °C. Compared to this binder course, significantly lower adhesion values are observed for conventional PMB thermoplastic binder courses.

[0118] In terms of adhesion performance, certain embodiments of this binder course provide excellent adhesion characteristics to asphalt pavements. Conventional systems, such as bituminous emulsions and bitumen thermoplastics, provide lower adhesion properties at high temperatures (30 - 60 °C) due to their lower softening points. In contrast, the binder courses described herein do not soften until they are activated, thus resulting in improved adhesion results. It should be noted that when the asphalt pavement itself is the weakest point in the composite system, the adhesion values will be lower than expected.

[0119] Another advantage of certain embodiments of the present invention over other reactive systems and asphalt emulsions is that they provide a fluid base for hot asphalt pavements, thereby achieving high compaction. This advantage also applies to asphalt pavement mixture designs with high void content, low asphalt content (high aggregate content), and large aggregate sizes. Additionally, increased asphalt compaction reduces the asphalt pavement thickness requirements, thereby reducing costs and labor. Compaction of asphalt is important because it reduces interconnected voids at the interface and subsequent water accumulation at the interface (see FIGS. 2-3). It is well known in the industry that interconnected voids and water accumulation should be avoided. See J C Nicholls et al., “Asphalt Surfacing to Bridge Decks“, TRL Report TRL655 (2006). The importance of reducing interconnected voids is also emphasized in the Highways England Design Manual for Roads and Bridges (Document CD358, Sections 6.4, 8.8, 8.8.1).

[0120] In the present disclosure, the term “average aggregate size” refers to a length measurement that roughly spans the diameter of the individual particles within a set. In the present disclosure, unless otherwise stated, the average aggregate size is obtained according to the BS EN 12697 (Parts 1, 2, 35) standard. Preferably, the asphalt applied to the binder layer composition taught by the present disclosure has an average aggregate size of about 1 mm or greater, 5 mm or greater, about 15 mm or greater, about 25 mm or greater, about 35 mm or greater, about 45 mm or greater, about 55 mm or greater, or within the range between any two of these values. More preferably, the average aggregate size of the asphalt is at most about 40 mm, more particularly at most about 35 mm. The upper limit of this range is envisioned to be about 55 mm, although this depends on the asphalt composition.

[0121] As previously mentioned, additives can be added at certain points during the foregoing formulation process. In the present disclosure, the term “additive” refers to an optional material that can be added to the binder layer composition. Additives can be added to alter or improve the desired properties in the binder layer composition, or to counteract the undesirable properties therein. Examples of additives include, but are not limited to, fillers, inhibitors, pigments, anti-settling aids, rheology modifiers, photoinitiators, UV stabilizers, degassing agents, antistatic agents, accelerators, catalysts, stabilizers, flame retardants, pH regulators, reinforcing agents, thickeners or diluents, elastic compounds, chain transfer agents, radiation absorption or reflection compounds, and other additives known in the art. The amount of additive used can be about 0-50 wt % of the composition in which the additive is present.

[0122] EXAMPLES / EXPERIMENTS

[0123] Although the present invention is described herein using a limited number of embodiments, these specific embodiments are not intended to limit the scope of the invention as otherwise described and claimed herein. There are modifications and variations to the described embodiments. More specifically, the following examples are given as specific examples of embodiments of the claimed invention. It should be understood that the present invention is not limited to the specific details given in the examples. Unless otherwise specified, all parts and percentages in the examples and the remainder of the specification are by weight of the total adhesive layer composition.

[0124] Example 1

[0125] Prepare a thermoplastic adhesive layer according to the following formulation:

[0126] (1) Component A

[0127] a. PMMA polymer, in an amount of about 10 - 30% by weight of the composition, wherein the PMMA polymer consists of one or more acrylate monomers having the structure H 2 C=C(R 1 )COOR 2 , and wherein one or more PMMA polymers can be used in the formulation;

[0128] b. Acrylate monomer, in an amount of about 5 - 45% by weight of the composition, wherein the acrylate monomer has the structure H 2 C=C(R 1 )COOR 2 ;

[0129] c. Tackifier, in an amount of about 10 - 50% by weight of the composition, wherein the tackifier comprises terpene phenols, styrenated terpenes, rosin esters, α-methylstyrene phenols, polyterpenes, or combinations thereof;

[0130] d. Plasticizer, in an amount of about 0.1 - 10% by weight of the composition, examples including adipates, dibutyl sebacate, dibutyl maleate, diisobutyl maleate, phthalates, terephthalates, phthalic dicarboxylates, phthalic tricarboxylates, trimellitates, benzoates, and others, including diisononyl 1,2-cyclohexanedicarboxylate (DINCH), organophosphates, glycols, polyethers, and bio-based plasticizers;

[0131] e. Optionally at least one additive, in an amount of about 0 - 50% by weight of the composition, examples including fillers, inhibitors, pigments, waxes, anti-settling aids, and rheological modifiers and other suitable additives for achieving certain purposes; and

[0132] f. A promoter in an amount of about 0 - 5% by weight of the composition, such as dimethylaniline, dimethyl-p-toluidine, methylhydroxyethyl-p-toluidine, or diisopropyltoluidine.

[0133] (2) Component B

[0134] A peroxide initiator suspension in an amount of up to about 10% by weight of the composition.

[0135] (3) Component C

[0136] a. A PMMA polymer in an amount of about 10 - 30% by weight of the composition, wherein the PMMA polymer is composed of one or more acrylate monomers having the structure H 2 C=C(R 1 )COOR 2 , and one or more PMMA polymers can be used in this formulation;

[0137] b. An acrylate monomer in an amount of about 5 - 45% by weight of the composition, wherein the acrylate monomer has the structure H 2 C=C(R 1 )COOR 2 ;

[0138] c. A tackifier in an amount of about 10 - 50% by weight of the composition, wherein the tackifier includes terpene phenols, styrenated terpenes, rosin esters, α-methylstyrene phenols, polyterpenes, or combinations thereof;

[0139] d. A plasticizer in an amount of about 0.1 - 10% by weight of the composition. Examples include adipates, dibutyl sebacate, dibutyl maleate, diisobutyl maleate, phthalates, terephthalates, phthalic dicarboxylates, phthalic tricarboxylates, trimellitates, benzoates, and others, including diisononyl cyclohexane-1,2-dicarboxylate (DINCH), organophosphates, glycols, polyethers, and bio-based plasticizers; and

[0140] e. Optionally, at least one additive in an amount of about 0 - 50% by weight of the composition. Examples include fillers, inhibitors, pigments, waxes, anti-settling aids, and rheological modifiers, etc., which are suitable additives for achieving certain purposes.

[0141] Activate Component C with Component B and place it under the pump branch pipe. Place Component A under the adjacent branch pipe, and spray the combined materials onto a waterproof membrane that is pre-laid on a primer-coated concrete substrate.

[0142] Two samples were prepared by spraying the prepared coating onto two depths (coating amounts) of approximately 600 gsm and approximately 1200 gsm respectively. The coating had a curing time of one (1) hour at 23 °C to provide a solid, smooth and seamless finish. The resulting composite material was then placed in a mold chamber where hot asphalt (∼160 °C) was compacted on top of the bonding layer to a thickness of approximately 50 mm. In this example, AC 10 type asphalt was used; this type of asphalt contains an average aggregate size of approximately 10 mm and has a tendency to generate a large number of interconnected voids. After the compaction was completed, the asphalt was cooled with water.

[0143] The resulting material was cut into appropriate specimen sizes and samples for tensile and shear adhesion tests were prepared according to the ETAG 033 standard (EN16596 and EN13653:2004 respectively). For the samples tested at 23 °C and 50 °C, the test results are shown in Table 2 below:

[0144]

[0145] Table 2. Shear and tensile adhesion of samples with 600- and 1200-gsm bonding layer thicknesses at 23 °C and 50 °C. It can be seen that the results meet the minimum requirements as present in the British national standard, such as CD358 (Waterproofing and Surfacing of Concrete Bridge Decks).

[0146] Significant compaction of the asphalt was also observed at the interface between the bonding layer and the road pavement layer - this is the result of using this bonding layer that melts when in contact with hot asphalt. The molten layer helps for better compaction at the interface, which results in a larger surface contact area between the asphalt and the bonding layer, and thus higher adhesion. In addition, this bonding layer allows aggregates to penetrate into and embed within it from the asphalt to produce a strong mechanical bond. At the same time, the molten bonding layer shifts upwards to fill any remaining voids at the interface. The improved surface contact area was confirmed by analyzing how much water penetrates the asphalt and reaches the bonding layer interface. For reference, a higher amount of water penetrating the asphalt indicates insufficient compaction of the asphalt due to larger voids at the interface and passages between the asphalt particles. A lower amount of water penetrating the asphalt to reach the interface indicates good compaction of the asphalt at the interface due to small or non-existent voids and passages between the asphalt particles. It was found that for such a composite system including the exemplary bonding layer, less than 1% of the water migrated to the bonding layer interface. Compared to a conventional system (not including PMB) with limited compaction at the interface, this system provides a more robust waterproofing system.

[0147] Example 2

[0148] Prepare the thermoplastic adhesive layer according to the formulation of Example 1. Prepare two samples by spraying the prepared coating onto two depths (coating amounts) of approximately 600 gsm and approximately 1200 gsm, respectively. The coating has a curing time of one (1) hour at 23 °C to provide a solid, smooth, and seamless finish. Then place the resulting composite material in a mold chamber where hot asphalt (∼160 °C) is compacted on top of the adhesive layer to a thickness of approximately 50 mm. In this example, AC32 type asphalt is used; this type of asphalt contains an average aggregate size of approximately 32 mm and has a tendency to generate a large number of interconnected voids. After the compaction is completed, cool the asphalt with water.

[0149] Cut the resulting material into appropriate specimen sizes and prepare samples for tensile and shear adhesion tests according to the ETAG 033 standard (EN16596 and EN13653:2004, respectively). For the samples tested at 23 °C and 50 °C, the test results are shown in Table 3 below:

[0150]

[0151] Table 3. Shear and tensile adhesion of samples with 600- and 1200-gsm adhesive layer thicknesses at 23 °C and 50 °C. It can be seen that the results meet the minimum requirements as present in the British national standard, such as CD358 (Waterproofing and Surfacing of Concrete Bridge Decks).

[0152] The above examples and embodiments are given by way of illustration only and are not intended to limit the scope of the present invention.

[0153] The above advantages and those that become apparent from the foregoing description are effectively achieved. Since certain changes can be made to the above construction without departing from the scope of the present invention, all matters contained in the foregoing description or shown in the accompanying drawings are intended to be construed as illustrative and not restrictive.

[0154] It is also to be understood that the following claims are intended to cover all general and specific features of the present invention described herein, as well as all statements of the scope of the present invention that, as a matter of language, might be said to fall between them.

Claims

1. A reactive cold-applied thermoplastic adhesive layer system, comprising: A first component, comprising: A polyacrylate polymer, which is polymethyl methacrylate and / or polymethyl methacrylate-co-n-butyl methacrylate, in an amount of 10-30% by weight of the composition, An acrylate monomer, in an amount of 5-45% by weight of the composition, A tackifier, in an amount of 10-50% by weight of the composition, wherein the tackifier is selected from terpene phenols, styrenated terpenes, rosin esters, α-methyl styrene phenols, polyterpenes or combinations thereof, A plasticizer, in an amount of 0.1-10% by weight of the composition, wherein the plasticizer is selected from adipates, dibutyl sebacate, dibutyl maleate, diisobutyl maleate, phthalates, terephthalates, trimellitates, benzoates and others, including diisononyl 1,2-cyclohexanedicarboxylate (DINCH), organophosphates, glycols, polyethers or bio-based plasticizers, and A promoter, in an amount of 0-5% by weight of the composition; and A second component, comprising an initiator suspension, in an amount of 0-10% by weight of the composition, wherein the mixture of the first component and the second component is sprayable or manually applicable and cures to form a solid adhesive layer.

2. The adhesive layer system according to claim 1, wherein the initiator suspension of the second component is a peroxide initiator suspension.

3. The adhesive layer system according to claim 1, wherein the first component further comprises at least one additive, in an amount of 0-50% by weight of the composition.

4. The adhesive layer system according to claim 3, wherein the at least one additive is selected from fillers, inhibitors, pigments, anti-settling aids, rheology modifiers, photoinitiators, UV stabilizers, degassing agents, antistatic agents, catalysts, stabilizers, flame retardants, pH regulators, reinforcing agents, thickeners or diluents, elastic compounds, chain transfer agents, radiation-absorbing compounds, radiation-reflecting compounds and combinations thereof.

5. The adhesive layer system according to claim 1, further comprising a third component, the third component comprising: A polyacrylate polymer, which is polymethyl methacrylate and / or polymethyl methacrylate-co-n-butyl methacrylate, in an amount of 10-30% by weight of the composition; An acrylate monomer, in an amount of 5-45% by weight of the composition; A tackifier, in an amount of 10-50% by weight of the composition, wherein the tackifier is selected from terpene phenols, styrenated terpenes, rosin esters, α-methyl styrene phenols, polyterpenes or combinations thereof; and A plasticizer, in an amount of 0.1-10% by weight of the composition, wherein the plasticizer is selected from adipates, dibutyl sebacate, dibutyl maleate, diisobutyl maleate, phthalates, terephthalates, trimellitates, benzoates and others, including diisononyl 1,2-cyclohexanedicarboxylate (DINCH), organophosphates, glycols, polyethers or bio-based plasticizers, wherein The mixture of the second component and the third component forms an activated third component, and The mixture of the first component and the activated third component is sprayable and cures to form an adhesive layer.

6. The adhesive layer system according to claim 5, wherein the third component further comprises at least one additive in an amount of 0 - 50 wt% of the composition.

7. The adhesive layer system according to claim 6, wherein the at least one additive is selected from fillers, inhibitors, pigments, anti - settling aids, rheology modifiers, photoinitiators, UV stabilizers, degassing agents, antistatic agents, catalysts, stabilizers, flame retardants, pH regulators, reinforcing agents, thickeners or diluents, elastic compounds, chain transfer agents, radiation - absorbing compounds, radiation - reflecting compounds, and combinations thereof.

8. The adhesive layer system according to claim 1, wherein the adhesive layer becomes a molten liquid after curing and when exposed to a temperature of 200 °C or lower, and its viscosity effectively compacts the road surface material applied to the adhesive layer and increases the surface contact area, so that the water permeability at the interface between the adhesive layer and the road surface material is 50% or less.

9. The adhesive layer system according to claim 8, wherein the water permeability at the interface between the adhesive layer and the road surface material is 1% or less.

10. The adhesive layer system according to claim 8, wherein the temperature is 100 °C or lower, and the viscosity is 6,000 cP or lower.

11. The adhesive layer system according to claim 1, wherein at a temperature of 23 °C and a coating amount of 600 - 1200 gsm, the shear adhesion between the substrate on which the adhesive layer is applied and the road surface material applied to the adhesive layer is 0.3 MPa to 3.0 MPa.

12. The adhesive layer system according to claim 1, wherein at a temperature of 23 °C and a coating amount of 600 - 1200 gsm, the tensile adhesion between the substrate on which the adhesive layer is applied and the road surface material applied to the adhesive layer is 0.3 MPa to 1.3 MPa.

13. A method of bonding a road surface material to a substrate, which comprises: mixing a first component and a second component together; wherein the first component comprises: a polyacrylate polymer, which is polymethyl methacrylate and / or polymethyl methacrylate - co - n - butyl methacrylate, in an amount of 10 - 30 wt% of the composition, acrylate monomers, in an amount of 5 - 45 wt% of the composition, a tackifier, in an amount of 10 - 50 wt% of the composition, wherein the tackifier is selected from terpene phenols, styrenated terpenes, rosin esters, α - methylstyrene phenols, polyterpenes, or combinations thereof, a plasticizer, in an amount of 0.1 - 10 wt% of the composition, wherein the plasticizer is selected from adipates, dibutyl sebacate, dibutyl maleate, diisobutyl maleate, phthalates, terephthalates, trimellitates, benzoates, and others, including diisononyl cyclohexane - 1,2 - dicarboxylate (DINCH), organophosphates, glycols, polyethers, or bio - based plasticizers, and an accelerator, in an amount of 0 - 5 wt% of the composition; wherein the second component comprises an initiator suspension in an amount of 0 - 10 wt% of the composition; applying the mixture to the substrate without using a heating element; curing the mixture to form a cured adhesive layer; A road surface material is applied to a cured bonding layer to form a composite material of the cured bonding layer and the road surface material, wherein the composite material bonds the road surface material to a substrate and provides a waterproof bond between the road surface material and the substrate.

14. The method according to claim 13, wherein the initiator suspension of the second component is a peroxide initiator suspension.

15. The method according to claim 13, wherein the road surface material comprises bitumen.

16. The method according to claim 15, wherein the bitumen is selected from asphalt concrete, hot rolled asphalt, stone mastic asphalt, asphalt mortar, porous asphalt, sand felt, and asphalt protective layer.

17. The method according to claim 15, wherein the bitumen has an average aggregate size of at most 55 mm.

18. The method according to claim 13, wherein the substrate comprises a waterproof membrane.

19. The method according to claim 13, wherein the step of applying the mixture to the substrate is carried out by spraying the mixture onto the substrate.

20. The method according to claim 13, wherein the mixture is applied to the substrate at a coating weight of 100 gsm to 1400 gsm.

21. The method according to claim 13, which further comprises mixing a third component with the second component to form an activated third component, which is then mixed with the first component and applied to the substrate.

22. The method according to claim 13, wherein after the road surface material is applied to the cured bonding layer, the road surface material can be compacted on the bonding layer so that the water permeability at the interface between the bonding layer and the road surface material is 50% or less.

23. The method according to claim 22, wherein the water permeability at the interface between the bonding layer and the road surface material is 1% or less.

24. The method according to claim 13, wherein the bonding layer becomes a molten liquid after curing and when exposed to a temperature of 200 °C or lower, and its viscosity effectively compacts the road surface material applied on the bonding layer and increases the surface contact area so that the water permeability at the interface between the bonding layer and the road surface material is 50% or less.

25. The method according to claim 24, wherein the water permeability at the interface between the bonding layer and the road surface material is 1% or less.

26. The method according to claim 24, wherein the temperature is 100 °C or lower and the viscosity is 6,000 cP or lower.

27. The method according to claim 13, wherein at a temperature of 23 °C and a coating weight of 600 - 1200 gsm, the shear adhesion between the substrate and the road surface material applied on the bonding layer is 0.3 MPa to 3.0 MPa.

28. The method according to claim 13, wherein at a temperature of 23 °C and a coating weight of 600 - 1200 gsm, the tensile adhesion between the substrate and the road surface material applied on the bonding layer is 0.3 MPa to 1.3 MPa.

29. A package or set, comprising: A first component, comprising: A polyacrylate polymer, which is polymethyl methacrylate and / or polymethyl methacrylate - co - n - butyl methacrylate, in an amount of 10 - 30% by weight of the composition, An acrylate monomer in an amount of 5-45% by weight of the composition, a tackifier in an amount of 10-50% by weight of the composition, wherein the tackifier is selected from terpene phenols, styrenated terpenes, rosin esters, α-methyl styrene phenols, polyterpenes or combinations thereof, a plasticizer in an amount of 0.1-10% by weight of the composition, wherein the plasticizer is selected from adipates, dibutyl sebacate, dibutyl maleate, diisobutyl maleate, phthalates, terephthalates, trimellitates, benzoates and others, including diisononyl 1,2-cyclohexanedicarboxylate (DINCH), organophosphates, glycols, polyethers or bio-based plasticizers, and a promoter in an amount of 0-5% by weight of the composition; and a second component comprising an initiator suspension in an amount of 0-10% by weight of the composition, an optional third component comprising: a polyacrylate polymer which is polymethyl methacrylate and / or polymethyl methacrylate-co-n-butyl methacrylate in an amount of 10-30% by weight of the composition; an acrylate monomer in an amount of 5-45% by weight of the composition; a tackifier in an amount of 10-50% by weight of the composition, wherein the tackifier is selected from terpene phenols, styrenated terpenes, rosin esters, α-methyl styrene phenols, polyterpenes or combinations thereof; and a plasticizer in an amount of 0.1-10% by weight of the composition, wherein the plasticizer is selected from adipates, dibutyl sebacate, dibutyl maleate, diisobutyl maleate, phthalates, terephthalates, trimellitates, benzoates and others, including diisononyl 1,2-cyclohexanedicarboxylate (DINCH), organophosphates, glycols, polyethers or bio-based plasticizers, wherein the mixture of the first component and the second component is sprayable or manually applicable and cured to form a solid adhesive layer, or when the third component is present, wherein the mixture of the second component and the third component forms an activated third component, and the mixture of the first component and the activated third component is sprayable and cured to form an adhesive layer.

30. The package or kit according to claim 29, wherein the initiator suspension of the second component is a peroxide initiator suspension.

31. A method of bonding a pavement material to a substrate using the package or kit of claim 29, which comprises: transporting the first component, the second component and the optional third component to a construction site; mixing the first component, the second component and the optional third component at the construction site; applying the mixture to the substrate without using a heating element; curing the mixture to form a cured adhesive layer; applying the pavement material to the cured adhesive layer to form a composite material of the cured adhesive layer and the pavement material, wherein the composite material bonds the pavement material to the substrate and provides a waterproof bond between the pavement material and the substrate.

32. The method according to claim 31, wherein the mixture is applied to the substrate by spraying.

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