num="0042">In one or more embodiments, these thermoplastic resins, prior to grafting, may have a melt temperature (T_m) that is from about 110° C. to about 250° C., in other embodiments from about 120 to about 170° C., and in other embodiments from about 130° C. to about 165° C. In one or more embodiments, they may have a crystallization temperature (T_c) of these optionally at least about 75° C., in other embodiments at least about 95° C., in other embodiments at least about 100° C., and in other embodiments at least 105° C., with one embodiment ranging from 105° to 115° C.

Exemplary thermoplastic polymers that may be grafted include polyolefins, polyolefin copolymers, and non-olefin thermoplastic polymers. Polyolefins may include those thermoplastic polymers that are formed by polymerizing ethylene or α-olefins such as propylene, 1-butene, 1-hexene, 1-octene, 2-methyl-1-propene, 3-methyl-1-pentene, 4-methyl-1-pentene, 5-methyl-1-hexene, and mixtures thereof. Copolymers of ethylene and propylene and ethylene and/or propylene with another α-olefin such as 1-butene, 1-hexene, 1-octene, 2-methyl-1-propene, 3-methyl-1-pentene, 4-methyl-1-pentene, 5-methyl-1-hexene or mixtures thereof is also contemplated. Other polyolefin copolymers may include copolymers of olefins with styrene such as styrene-ethylene copolymer or polymers of olefins with α,β-unsaturated acids, α,β-unsaturated esters such as polyethylene-acrylate copolymers. Non-olefin thermoplastic polymers may include polymers and copolymers of styrene, α,β-unsaturated acids, α,β-unsaturated esters, and mixtures thereof. For example, polystyrene, polyacrylate, and polymethacrylate may be functionalized.

These homopolymers and copolymers may be synthesized by using an appropriate polymerization technique known in the art. These techniques may include conventional Ziegler-Natta, type polymerizations, catalysis employing single-site organometallic catalysts including, but not limited to, metallocene catalysts, and high-pressure free radical polymerizations.

The degree of functionalization of the functionalized thermoplastic polymer may be recited in terms of the weight percent of the pendent functional moiety based on the total weight of the functionalized polymer. In one or more embodiments, the functionalized thermoplastic polymer may include at least 0.2% by weight, in other embodiments at least 0.4% by weight, in other embodiments at least 0.6% by weight, and in other embodiments at least 1.0 weight percent functionalization, in these or other embodiments, the functionalized thermoplastic polymers may include less than 10% by weight, in other embodiments less than 5% by weight, in other embodiments less than 3% by weight, and in other embodiments less than 2% by weight functionalization.

In one or more embodiments, where the functionalized thermoplastic polymer is a functionalized propylene-based polymer, it can be characterized by a melt flow rate of from about 20 to about 2,000 dg/min, in other embodiments from about 100 to about 1,500 dg/min, and in other embodiments from about 150 to about 750 dg/min, per ASTM D-1238 at 230° C. and 2.16 kg load. In one or more embodiments, where the functionalized thermoplastic polymer is a functionalized ethylene-based polymer, it can be characterized by a melt flow index of from about 0.2 to about 2,000 dg/min, in other embodiments from about 1 to about 1,000 dg/min, and in other embodiments from about 5 to about 100 dg/min, per ASTM D-1238 at 190° C. and 2.16 kg load.

Functionalized thermoplastic polymers are commercially available. For example, maleated propylene-based polymers may be obtained under the tradename FUSABOND™ (DuPont), POLYBOND™ (Crompton), and EXXELOR™ (ExxonMobil). Another examples includes polymers or oligomers including one or more glycidyl methacrylate groups such as Lotader™ AX8950 (Arkema).

Mineral Fillers

As indicated above, at least the bottom layer of the membranes of the present invention include a filler (e.g. a mineral filler). In particular embodiments, the cap layer and the bottom layer include mineral filler. In other embodiments all layers of the membrane include mineral filler. In one or more embodiments, the mineral fillers include inorganic materials that may aid in reinforcement, heat aging resistance, green strength performance, and/or flame resistance. In other embodiments, these materials are generally inert with respect to the composition and therefore simply act as diluent to the polymeric constituents. In one or more embodiments, mineral fillers include clays, silicates, titanium dioxide, talc (magnesium silicate), mica (mixtures of sodium and potassium aluminum silicate), alumina trihydrate, antimony trioxide, calcium carbonate, titanium dioxide, silica, magnesium hydroxide, calcium borate ore, and mixtures thereof. In one or more embodiments, the fillers are not surface modified or surface functionalized.

Suitable clays may include airfloated clays, water-washed clays, calcined clays, surface-treated clays, chemically-modified clays, and mixtures thereof.

Suitable silicates may include synthetic amorphous calcium silicates, precipitated, amorphous sodium aluminosilicates, and mixtures thereof.

Suitable silica (silicon dioxide) may include wet-processed, hydrated silicas, crystalline silicas, and amorphous silicas (noncrystalline).

In one or more embodiments, the mineral fillers are characterized by an average particle size of at least 1 μm, in other embodiments at least 2 μm, in other embodiments at least 3 μm, in other embodiments at least 4 μm, and in other embodiments at least 5 μm. In these or other embodiments, the mineral fillers are characterized by an average particle size of less than 15 μm, in other embodiments less than 12 μm, in other embodiments less than 10 μm, and in other embodiments less than 8μm. In these or other embodiments, the mineral filler has an average particle size of between 1 and 15 μm, in other embodiments between 3 and 12 μm, and in other embodiments between 6 and 10 μm.

Other Ingredients

The thermoplastic membranes of the present invention (e.g., one or more layers of the membranes) may also include other ingredients, such as those that are conventional in thermoplastic membranes. For example, other useful additives or constituents may include flame retardants, stabilizers, pigments, and fillers.

In one or more embodiments, useful flame retardants include and compound that will increase the burn resistivity, particularly flame spread such as tested by UL 94 and/or UL 790, of the laminates of the present invention. Useful flame retardants include those that operate by forming a char-layer across the surface of a specimen when exposed to a flame. Other flame retardants include those that operate by releasing water upon thermal decomposition of the flame retardant compound. Useful flame retardants may also be categorized as halogenated flame retardants or non-halogenated flame retardants.

Exemplary non-halogenated flame retardants include magnesium hydroxide, aluminum trihydrate, zinc borate, ammonium polyphosphate, melamine polyphosphate, and antimony oxide (Sb₂O₃). Magnesium hydroxide (Mg(OH)₂) is commercially available under the tradename Vertex™ 60, ammonium polyphosphate is commercially available under the tradename Exolite™ AP 760 (Clarian), which is sold together as a polyol masterbatch, melamine polyphosphate is available under the tradename Budit™ 3141 (Budenheim), and antimony oxide (Sb₂O₃) is commercially available under the tradename Fireshield™. Those flame retardants from the foregoing list that are believed to operate by forming a char layer include ammonium polyphosphate and melamine polyphosphate.

In one or more embodiments, treated or functionalized magnesium hydroxide may be employed. For example, magnesium oxide treated with or reacted with a carboxylic acid or anhydride may be employed. In one embodiment, the magnesium hydroxide may be treated or reacted with stearic acid. In other embodiments, the magnesium hydroxide may be treated with or reacted with certain silicon-containing compounds. The silicon-containing compounds may include silanes, polysiloxanes including silane reactive groups. In other embodiments, the magnesium hydroxide may be treated with maleic anhydride. Treated magnesium hydroxide is commercially available. For example, Zerogen™ 50.

Examples of halogenated flame retardants may include halogenated organic species or hydrocarbons such as hexabromocyclododecane or N,N′-ethylene-bis-(tetrabromophthalimide). Hexabromocyclododecane is commercially available under the tradename CD-75P™ (ChemTura). N,N′-ethylene-bis-(tetrabromophthalimide) commercially available under the tradename Saytex™ BT-93 (Albemarle).

In one or more embodiments, the use of char-forming flame retardants (e.g. ammonium polyphosphate and melamine polyphosphate) has unexpectedly shown advantageous results when used in conjunction with nanoclay within the cap layer of the laminates of the present invention. It is believed that there may be a synergistic effect when these compounds are present in the cap layer. As a result, the cap layer of the laminates of the certain embodiments of the present invention are devoid of or substantially devoid of halogenated flame retardants and/or flame retardants that release water upon thermal decomposition. Substantially devoid referring to that amount or less that does not have an appreciable impact on the laminates, the cap layer, and/or the burn resistivity of the laminates.

In one or more embodiments, the membranes of the invention may include a stabilizers. Stabilizers may include one or more of a UV stabilizer, an antioxidant, and an antiozonant. UV stabilizers include Tinuvin™ 622. Antioxidants include Irganox™ 1010.

In one or more embodiments, one or more layers of the membranes of the present invention may include expandable graphite, which may also be referred to as expandable flake graphite, intumescent flake graphite, or expandable flake. Generally, expandable graphite includes intercalated graphite in which an intercallant material is included between the graphite layers of graphite crystal or particle. Examples of intercallant materials include halogens, alkali metals, sulfates, nitrates, various organic acids, aluminum chlorides, ferric chlorides, other metal halides, arsenic sulfides, and thallium sulfides. In certain embodiments of the present invention, the expandable graphite includes non-halogenated intercallant materials. In certain embodiments, the expandable graphite includes sulfate intercallants, also referred to as graphite bisulfate. As is known in the art, bisulfate intercalation is achieved by treating highly crystalline natural flake graphite with a mixture of sulfuric acid and other oxidizing agents which act to catalyze the sulfate intercalation. Expandable graphite useful in the applications of the present invention are generally known as described in International Publ. No. WO/2014/078760, which is incorporated herein by reference.

Commercially available examples of expandable graphite include HPMS Expandable Graphite (HP Materials Solutions, Inc., Woodland Hills, CA) and Expandable Graphite Grades 1721 (Asbury Carbons, Asbury, NJ). Other commercial grades contemplated as useful in the present invention include 1722, 3393, 3577, 3626, and 1722HT (Asbury Carbons, Asbury, NJ).

In one or more embodiments, the expandable graphite may be characterized as having a mean or average size in the range from about 30 μm to about 1.5 mm, in other embodiments from about 50 μm to about 1.0 mm, and in other embodiments from about 180 to about 850 μm. In certain embodiments, the expandable graphite may be characterized as having a mean or average size of at least 30 μm, in other embodiments at least 44 μm, in other embodiments at least 180 μm, and in other embodiments at least 300 μm. In one or more embodiments, expandable graphite may be characterized as having a mean or average size of at most 1.5 mm, in other embodiments at most 1.0 mm, in other embodiments at most 850 μm, in other embodiments at most 600 μm, in yet other embodiments at most 500 μm, and in still other embodiments at most 400 μm. Useful expandable graphite includes Graphite Grade #1721 (Asbury Carbons), which has a nominal size of greater than 300 μm.

In one or more embodiments of the present invention, the expandable graphite may be characterized as having a nominal particle size of 20×50 (US sieve). US sieve 20 has an opening equivalent to 0.841 mm and US sieve 50 has an opening equivalent to 0.297 mm. Therefore, a nominal particle size of 20×50 indicates the graphite particles are at least 0.297 mm and at most 0.841 mm.

In one or more embodiments, the expandable graphite may be characterized by an onset temperature ranging from about 100° C. to about 250° C.; in other embodiments from about 160° C. to about 225° C.; and in other embodiments from about 180° C. to about 200°° C. In one or more embodiments, the expandable graphite may be characterized by an onset temperature of at least 100° C., in other embodiments at least 130° C., in other embodiments at least 160° C., and in other embodiments at least 180° C. In one or more embodiments, the expandable graphite may be characterized by an onset temperature of at most 250° C., in other embodiments at most 225° C., and in other embodiments at most 200° C. Onset temperature may also be interchangeably referred to as expansion temperature; and may also be referred to as the temperature at which expansion of the graphite starts.

In one or more embodiments, one or more layers of the membranes of the present invention include a nanoclay. Nanoclays include the smectite clays, which may also be referred to as layered silicate minerals. Useful clays are generally known as described in U.S. Pat. No. 6,414,070 and U.S. Pat. Publ. No. 2009/0269565, which are incorporated herein by reference. In one or more embodiments, these clays include exchangeable cations that can be treated with organic swelling agents such as organic ammonium ions, to intercalate the organic molecules between adjacent planar silicate layers, thereby substantially increasing the interlayer spacing. The expansion of the interlayer distance of the layered silicate can facilitate the intercalation of the clay with other materials. The interlayer spacing of the silicates can be further increased by formation of the polymerized monomer chains between the silicate layers. The intercalated silicate platelets act as a nanoscale (sub-micron size) filler for the polymer.

Intercalation of the silicate layers in the clay can take place either by cation exchange or by absorption. For intercalation by absorption, dipolar functional organic molecules such as nitrile, carboxylic acid, hydroxy, and pyrrolidone groups are desirably present on the clay surface. Intercalation by absorption can take place when either acid or non-acid clays are used as the starting material. Cation exchange can take place if an ionic clay containing ions such as, for example, Na⁺, K⁺, Ca⁺⁺, Ba⁺⁺, and Li⁺ is used. Ionic clays can also absorb dipolar organic molecules.

Smectite clays include, for example, montmorillonite, saponite, beidellite, hectorite, and stevensite. In one or more embodiments, the space between silicate layers may be from about 15 to about 40×, and in other embodiments from about 17 to about 36×, as measured by small angle X-ray scattering. Typically, a clay with exchangeable cations such as sodium, calcium and lithium ions may be used. Montmorillonite in the sodium exchanged form is employed in one or more embodiments

Organic swelling agents that can be used to treat the clay include quaternary ammonium compound, excluding pyridinium ion, such as, for example, poly(propylene glycol)bis)2-aminopropyl ether), poly (vinylpyrrolidone), dodecylamine hydrochloride, octadecylamine hydrochloride, and dodecylpyrrolidone. These treated clays are commercially available. One or more of these swelling agents can be used.

Amounts

As discussed above, a planar surface of the membranes of the present invention are abraded or otherwise treated to expose mineral filler contained with the layer forming the exposed planar surface of the membrane. In one or more embodiments, the layer forming the surface that is abraded or otherwise treated includes greater than 5, in other embodiments greater than 10, in other embodiments greater than 15 weight percent, in other embodiments greater than 20 weight percent, in other embodiments greater than 25 weight percent, in other embodiments greater than 30 weight percent, in other embodiments greater than 33 weight percent, in other embodiments greater than 40 weight percent, and in other embodiments greater than 45 weight percent of the mineral filler based on the entire weight of the given layer of the membrane that includes the filler. In one or more embodiments, the layer forming the surface that is abraded or otherwise treated includes less than 80 weight percent, in other embodiments less than 70 weight percent, and in other embodiments less than 60 weight percent of the filler based on the entire weight of the given layer of the membrane that includes the filler. In one or more embodiments, the layer forming the surface that is abraded or otherwise treated includes from about 5 to about 80, in other embodiments from about 10 to about 70, and in other embodiments from about 20 to about 60 weight percent of the filler based upon the entire weight of the given layer of the membrane that includes the filler.

Method of Making

In one or more embodiments, the compositions and membranes of the present invention may be prepared by employing conventional techniques. The polymeric composition that may be extruded to form the polymeric sheet may include the ingredients or constituents described herein. For example, the polymeric composition may include thermoplastic polyolefin, filler, and the other optional ingredients defined herein. The ingredients may be mixed together by employing conventional polymer mixing equipment and techniques. In one or more embodiments, an extruder may be employed to mix the ingredients. For example, single-screw or twin-screw extruders may be employed. The various ingredients can be separately fed into a reaction extruder and pelletized or directly extruded into membrane or laminate sheet. In other embodiments, the various ingredients can be combined and mixed within a mixing apparatus such as an internal mixer and then subsequently fabricated into membrane sheets or laminates.

In one or more embodiments, the membranes of the present invention may be prepared by extruding a polymeric composition into a sheet. Multiple sheets may be extruded and joined to form a laminate. A membrane including a reinforcing layer may be prepared by extruding at least one sheet on and/or below a reinforcement (e.g., a scrim). In other embodiments, the polymeric layer may be prepared as separate sheets, and the sheets may then be calandered with the scrim sandwiched there between to form a laminate. In one or more embodiments, one or more layers of the membranes of the present invention are prepared by employing coextrusion technology. Useful techniques include those described in U.S. Pat. Nos. 7,882,671 and U.S. Ser. No. 11/708,903, which are incorporated herein by reference.

Following extrusion, and after optionally joining one or more polymeric layers, or optionally joining one or more polymeric layer together with a reinforcement, the membrane may be fabricated to a desired thickness. This may be accomplished by passing the membrane through a set of squeeze rolls positioned at a desired thickness. The membrane may then be allowed to cool and/or optionally rolled for storage.

Exposure of Mineral Fillers

In accordance with practice of this invention, the thermoplastic membrane (or a surface thereof) is subjected to mechanical treatment to provide a planar surface that includes exposed mineral filler. This surface may be referred to as an abraded surface. Generally, it is believed that the membrane surface has limited exposed mineral filler following the extrusion process due to the presence of a film or layer of thermoplastic resin across the surface of the membrane; e.g. a film or layer having a thickness of at least 0.5 μm coats the planar surface of the membrane. Mechanical treatment according the present invention at least partially removes this film or layer to expose the mineral filler to the surface.

In one or more embodiments, mechanical treatment of a surface of the membrane takes place as part of the manufacturing process of the membrane. In other embodiments, the mechanical treatment of a surface of the membrane takes place as part of a post-manufacturing process (e.g. after winding, storage, and/or shipment of the membrane). In either event, the mechanical treatment of a surface of the membrane takes place at membrane temperatures (i.e. the temperature of the surface of the membrane being treated) below those temperatures that would otherwise frustrate the abrading process. For example, in one or more embodiments, the mechanical treatment takes place below the melt temperature of the thermoplastic material forming the skin or layer. In one or more embodiments, mechanical treatment takes place at temperatures less than 100° C., in other embodiments less than 50° C., and in other embodiments less than 30° C. In one or more embodiments, mechanical treatment takes place at membrane temperatures of form about 0°° C. to about 100° C., in other embodiments from about 10°° C. to about 50° C., and in other embodiments from about 15° C. to about 30° C.

In one or more embodiments, mechanical treatment of the surface of the membrane can be accomplished by abrading, sanding, or shaving the surface of the membrane. This step can be accomplished by contacting the surface with a sanding, abrading, or shaving element. In one or more embodiments, these elements may include a file or knurled surface. For example, single-cut or double-cut filed or knurled surface elements may be employed. In other embodiments, these elements may include abrasive surfaces such as, but not limited to, diamond, ceramic, aluminum oxide, or silicon oxide file elements or other coated abrasives or sanding elements such as sandpaper (e.g. aluminum oxide paper or silicon carbide paper). In yet other embodiments, the elements include bristled devices such as wire brushes. In one or more embodiments, these elements are static or stationary devices that treat the surface of the membrane by contacting and passing the membrane across the surface of the element. In other embodiments, the elements are dynamic or active (e.g. rotating) to thereby impart greater force or otherwise more efficiently impact the surface of the membrane to thereby abrade the surface thereof.

In one or more embodiments, at least a substantial portion of the surface of the membrane is mechanically treated to expose the mineral filler. In particular embodiments, at least 80%, in other embodiments at least 90%, and in other embodiments at least 98% of the surface area of a surface of the membrane is treated to thereby expose mineral filler.

An exemplary process for producing membrane according to the present invention can be described with reference to FIG. 3, which shows process configuration 32 including first extrusion die 34 and second extrusion die 36. First extrusion die 34 produces first thermoplastic sheet 38, and second extrusion die 36 produces second thermoplastic sheet 40. First thermoplastic sheet 38 includes mineral filler (not shown). The skilled person will appreciate that where first thermoplastic sheet 38 is a coextruded sheet, at least the outer layer thereof will include mineral filler. First and second dies 34, 36 feed first and second sheets 38, 40 to a pair of nip rolls 42, 44, which also receive reinforcing fabric 46 between sheets 38, 40. The sandwiching of fabric 46 between first and second sheets 38, 40, while sheets 38, 40 are in a molten state, thereby laminates sheets 38, 40 with fabric 46 sandwiched there between to produce bilaminate sheet 47 having first surface 48 and second surface 50. Bilaminate sheet 47 is then routed around rolls 44 and 52, which are chilled rolls that serve to cool the membrane. Bilaminate membrane 47 is then tensioned around a rotating, knurled rod 56, which abrades second surface 50 and thereby exposes mineral filler contained therein. Following the mechanical treatment of surface 50 by knurled rod 56, membrane 47 can be processed by conventional means, which includes, for example, accumulating 58 within a series of rolls, winding 60, storage 62, and shipping 64.

INDUSTRIAL APPLICABILITY

As indicated above, the membranes of one or more embodiments of the present invention are useful for roofing membranes for covering flat or low-sloped roofs to thereby form a roofing system. These roof systems are generally known in the art as disclosed in U.S. Ser. Nos. 60/586,424 and 11/343,466, and International Application No. PCT/US2005/024232, which are incorporated herein by reference. Advantageously, the membranes of one or more embodiments of the present invention may be used to form fully-adhered roofing systems through the use of polar adhesives even though the membranes of this invention are devoid of fabric backings, which backings are conventionally present when polar adhesives are employed.

In one or more embodiments, roof systems can be described with reference to FIG. 4, which shows adhered-roofing system 70 including roof deck 72, optional insulation layer 74, optional coverboard layer 76, thermoplastic membrane 80, and adhesive layer 82. Advantageously, the membranes of the present invention can be used to prepare adhered roofing systems, including fully-adhered systems and partially-adhered systems. In this regard, at least a portion of the abraded or otherwise treated surface of the lower most portion of the membrane is adhesively mated to the substrate through a polar adhesive. Namely, membrane 80 is adhesively secured to the substrate through adhesive layer 82. The substrate may include one or more of an existing membrane (not shown), coverboard 76, insulation layer 74, or roof deck 72. As used within the specification, the term “fully-adhered roofing system” refers to a roofing system wherein the primary mode of attachment of the membrane to the underlying substrate is through the use of an adhesive. In one or more embodiments, this mode of attachment includes the situation where at least 50%, in other embodiments at least 70%, in other embodiments at least 90%, and in other embodiments at least 98% of the underlying surface of the membrane (i.e., the substrate-contacting planar surface of the membrane) is adhered to the substrate through an adhesive.

Generally, these roof systems are formed by applying the polar adhesive to the roof substrate to form a layer of adhesive, and then the membranes of the present invention, which are devoid of any fleece backing, can subsequently be contacted to the layer of adhesive disposed on the substrate. The polar adhesive then cures, such as by reaction with atmospheric water, to produce a cured residue of the adhesive composition that binds or is otherwise adhesively mated to the roof substrate and the membrane. Advantageously, the process can be used to construct roofing systems that meet the standards of UL and Factory Mutual for wind uplift in the absence of a fleece or other backing material applied to the membrane.

In one or more embodiments, the roof deck may include steel, concrete, and/or wood. In these or other embodiments, the membranes may be applied over additional materials, such as insulation boards and cover boards. As those skilled in the art appreciate, insulation boards and cover boards may carry a variety of facer materials including, but not limited to, paper facers, fiberglass-reinforced paper facers, fiberglass facers, coated fiberglass facers, metal facers such as aluminum facers, and solid facers such as wood. In yet other embodiments, the membranes may be applied over existing membranes. These existing membranes may include cured rubber systems such as EPDM membranes, thermoplastic polymers systems such as TPO membranes, or asphalt-based systems such as modified asphalt membranes and/or built roof systems.

Practice of this invention is not limited by the selection of any particular roof deck. Accordingly, the roofing systems herein can include a variety of roof decks. Exemplary roof decks include concrete pads, steel decks, wood beams, and foamed concrete decks.

Practice of this invention is likewise not limited by the selection of any particular insulation board. Moreover, the insulation boards are optional. Several insulation materials can be employed including polyurethane or polyisocyanurate cellular materials. These boards are known as described in U.S. Pat. Nos. 6,117,375, 6,044,604, 5,891,563, 5,573,092, U.S. Publication Nos. 2004/0109983, 2003/0082365, 2003/0153656, 2003/0032351, and 2002/0013379, as well as U.S. Ser. Nos. 10/640,895, 10/925,654, and 10/632,343, which are incorporated herein by reference. In one or more embodiments, cover boards may include high density polyurethane or polyisocyanurate board as disclosed in U.S. Publ. Nos. 2006/0127664, 2013/0164524, 2014/0011008, 2013/0036694, and 2012/0167510 which are incorporated herein by reference. In other embodiments, the cover boards may include construction boards such as DensDeck.

In other embodiments, these membranes may be employed to cover flat or low-slope roofs following a re-roofing event. In one or more embodiments, the membranes may be employed for re-roofing as described in U.S. Publication No. 2006/0179749, which are incorporated herein by reference.

Polar Adhesives

In one or more embodiments, the membranes of the present invention may be adhered to a roof substrate, or seamed to adjacent membranes within a roofing system, by us of a polar adhesive system. These adhesive systems may advantageously be applied to a roof substrate as a liquid or foam. In one or more embodiments, these polar adhesive systems may include, but are not limited to, polysiloxane adhesives, silicon-terminated polymers or functionalized polymers, and isocyanate-reactive adhesive systems. As is known in the art, these adhesive systems may also include a tackifier resin, an adhesion promoter, a filler, a catalyst, an antioxidant, a stabilizer, a moisture scavenger, a crosslink inhibitor (a.k.a retarder), a plasticizer, and/or a thixotropic compound. In one or more embodiments, the adhesive composition is a 100% solids composition (i.e. it is solvent free). Adhesive compositions of this nature are described in International Publication No. WO 2014/145482 and U.S. Pat. No. 7,767,308, which are incorporated herein by reference.

In one or more embodiments, the polymers having silicon-containing hydrolyzable terminal groups may include silane-terminated polymers, which may also be referred to as silyl-terminated polymers. The term “silicon-containing hydrolyzable terminal group” as used herein means a group wherein at least one silicon atom is combined with a hydrolyzable group such as a methoxy group which is subject to hydrolysis and polymerization by moisture. The backbone of the polymer having silicon-containing hydrolyzable terminal groups may be comprised of polyethers, polyesters, polyurethanes (SPUR), or other suitable backbones.

Suitable polymers having silicon-containing hydrolyzable terminal groups are commercially available and/or can be prepared in accordance with techniques known in the art. Examples of suitable commercially available polymers having silicon-containing hydrolyzable terminal groups are Geniosil™. STP-E 35 trimethoxysilylpropyl-carbamate-terminated polyether, and Geniosil™. STP-E 30 silane-terminated polyether with dimethoxy(methyl)silylmethylcarbamate terminal groups, both of which are available from Wacker Chemical. Another commercially available polymer having silicon-containing hydrolyzable terminal groups that may be employed in the adhesive compositions of this invention is “SPUR+” silane-terminated polyurethanes, which are available from Momentive. Another suitable commercially available material is “MS” silyl-terminated polyether (S227H, S303, S327, S303H, SAX350), available from Kaneka.

In one or more embodiments, the tackifier resin is a hydrocarbon resin. In other embodiments, the tackifier resin is a phenolic resin.

In one or more embodiments, the hydrocarbon resins may include natural resins, synthetic resins, and low molecular weight polymers or oligomers. The monomer that may be polymerized to synthesize the synthetic resins or low molecular weight polymers or oligomers may include those obtained from refinery streams containing mixtures or various unsaturated materials or from pure monomer feeds. The monomer may include aliphatic monomer, cycloaliphatic monomer, aromatic monomer, or mixtures thereof. Aliphatic monomer can include C₄, C₅, and C₆paraffins, olefins, and conjugated diolefins. Examples of aliphatic monomer or cycloaliphatic monomer include butadiene, isobutylene, 1,3-pentadiene (piperylene) along with 1,4-pentadiene, cyclopentane, 1-pentene, 2-pentene, 2-methyl-1-pentene, 2-methyl-2-butene, 2-methyl-2-pentene, isoprene, cyclohexane, 1-3-hexadiene, 1-4-hexadiene, cyclopentadiene, and dicyclopentadiene. Aromatic monomer can include C₈, C₉, and C₁₀aromatic monomer. Examples of aromatic monomer include styrene, indene, derivatives of styrene, derivatives of indene, and combinations thereof.

In one or more embodiments, examples of hydrocarbon resins include aliphatic hydrocarbon resins, at least partially hydrogenated aliphatic hydrocarbon resins, aliphatic/aromatic hydrocarbon resins, at least partially hydrogenated aliphatic aromatic hydrocarbon resins, cycloaliphatic hydrocarbon resins, at least partially hydrogenated cycloaliphatic resins, cycloaliphatic/aromatic hydrocarbon resins, at least partially hydrogenated cycloaliphatic/aromatic hydrocarbon resins, at least partially hydrogenated aromatic hydrocarbon resins, polyterpene resins, terpene-phenol resins, rosin esters, and mixtures of two or more thereof.

In certain embodiments, the synthetic aliphatic or aromatic hydrocarbon resins may be characterized by a number average molecular weight (M_n) of from about 300 g/mole to about 3,000 g/mole, and in other embodiments from about 500 g/mole to about 2,000g/mole. These hydrocarbon resins may also be characterized by a weight average molecular weight (M_w) of from about 500 g/mole to about 6,000 g/mole, and in other embodiments from about 700 g/mole to about 5,000 g/mole. Molecular weight may be determined by size exclusion chromatography (SEC) by using a Waters 150 gel permeation chromatograph equipped with the differential refractive index detector and calibrated using polystyrene standards.

In certain embodiments, the hydrocarbon resins include those produced by thermal polymerization of dicyclopentadiene (DCPD) or substituted DCPD, which may further include aliphatic or aromatic monomers. In one embodiment, the DCPD or substituted DCPD is copolymerized with aromatic monomer, and the final product includes less than 10% aromatic content. In another embodiment, the hydrocarbon resin derives from the copolymerization of both aliphatic monomer and aromatic monomer. In particular embodiments, the dicyclopentadiene tackifier resin is hydrogenated. Hydrogenated dicyclopentadiene tackifier resins are commercially available from Neville.

In one or more embodiments, synthetic oligomers may include dimers, trimers, tetramers, pentamers, hexamers, septamers, and octamers of petroleum distillate monomer. In one or more embodiments, this petroleum distillate monomer may have a boiling point of from about 30° to about 210° C. The oligomers may include byproducts of resin polymerization including thermal and catalytic polymerization. For example, oligomers may derive from processes where DCPD, aliphatic monomer, and/or aromatic monomer are oligomerized.

The hydrocarbon resins may be characterized by an aromatic content of from about 1 to about 60, in other embodiments from about 2 to about 40, and in other embodiments from about 5 to about 10. In one or more embodiments, the tackifier resins are hydrogenated or partially hydrogenated; useful resins include those that are at least 50percent, in other embodiments at least 80 percent, in other embodiments at least 95 percent, and in other embodiments at least 99 percent or fully hydrogenated. For example, the hydrocarbon resin prior to grafting may contain less than 90, in other embodiments less than 50, in other embodiments less than 25, in other embodiments less than 10, in other embodiments less than 2, in other embodiments less than 1, in other embodiments less than 0.5, and in other embodiments less than 0.05 olefinic protons. Aromatic content and olefin content may be measured by ¹H-NMR as measured directly from the ¹H NMR spectrum from a spectrometer with a field strength greater than 300 MHz, and in other embodiments 400 MHz (frequency equivalent). Aromatic content includes the integration of aromatic protons versus the total number of protons. Olefin proton or olefinic proton content includes the integration of olefinic protons versus the total number of protons.

In one or more embodiments, the hydrocarbon resin may be characterized by a softening point of from about 5°° C. to about 210° C., in other embodiments from about 65° C. to about 170° C., and in other embodiments from about 90° C. to about 140° C. Softening point can be determined according to ASTM E-28 (Revision 1996).

In these or other embodiments, the hydrocarbon resin may be characterized by a glass transition temperature of less than 120° C., in other embodiments less than 110° C., and in other embodiment from about −40° C. to about 80° C. Glass transition temperature may be determined according to ASTM D 341-88 by using differential scanning calorimetry.

In these or other embodiments, the hydrocarbon resin may be characterized by a Saponification number (mg KOH/g resin material) of greater than 10, in other embodiments greater than 15, and in other embodiments greater than 19.

In these or other embodiments, the hydrocarbon resin may be characterized by an acid number greater than 10, in other embodiments greater than 15, and in other embodiments greater than 20, and in other embodiments greater than 25.

In particular embodiments, the tackifier resin is a phenolic resin. In one or more embodiments, the phenolic resins that may be employed in the compositions of this invention include resol-type and novolak-type phenolic resins obtained by condensation reaction of phenolic compounds, e.g., phenol, cresol, xylenol, resorcinol, an alkylphenol, and a modified phenol such as cashew nut shell oil modified phenol or tall oil modified phenol, with aldehyde compounds, e.g., formaldehyde and paraformaldehyde; and nitrogen-containing phenol resins obtained by condensation reaction of the above-mentioned phenolic compounds and aldehyde compounds in the presence of a catalyst such as ammonia or an amine compound. The phenol resins may be employed alone or in admixture. In one or more embodiments, the term phenolic resin refers to a phenol-formaldehyde resin. For example, the term phenolic resin may include a novolac resin, which is a phenol-formaldehyde resin where the molar ratio of the formaldehyde to phenol is less than one. These resins are typically synthesized by using an acid catalyst. The term phenolic resin also refers to resol resins wherein the molar ratio of the formaldehyde to phenol is greater than one. These resins are typically synthesized by using a base catalyst.

In one or more embodiments, the adhesion promoter includes a non-polymeric silicon-containing hydrocarbon compound that has a lower molecular weight than the polymer having a silicon-containing hydrolysable group (i.e. the silane-terminate polymer). Also, the adhesion promoter includes at least one hydrolyzable group capable of reacting with a hydrolyzed functional group on the polymer having silicon-containing hydrolyzable terminal groups, and includes at least one moiety capable of interacting (i.e., promoting adhesion) with materials that are to be bonded with one another (such as a rubber membrane material). The expression non-polymeric, as used to modify the silicon-containing hydrocarbon compound is meant to exclude polymers and copolymers having at least 10 repeat units or monomeric units, such as urethane prepolymers having silicon-containing hydrolyzable terminal groups, but is meant to encompass oligomeric silicon-containing hydrolyzable compounds having fewer than 10 repeat units or monomers, and which are useful for promoting adhesion between a substrate and a cured adhesive composition. Examples of suitable aminosilane adhesion promoters that may function as the non-polymeric silicon-containing hydrolyzable compound include, but are not limited to gamma-aminopropyltrimethoxysilane, gamma-aminopropyltriethoxysilane, gamma-(aminoethyl)-aminopropyltrimethoxy-silane, methylaminopropyldimethoxysilane, methyl-gamma-(aminoethyl)-aminopropyldimethoxysilane, gamma-dimethylaminopropyltrimethoxysilane, and the like.

In one or more embodiments, examples of a plasticizer include phthalic acid esters (such as dioctyl phthalate, diisooctyl phthalate, dibutyl phthalate, diundecyl phthalate, diisononyl phthalate, diisodecyl phthalate, diisodocecyl phthalate and butylbenzyl phthalate); aliphatic dibasic acid esters (such as dioctyl adipate, isodecyl succinate, and dibutyl sebacate); glycol esters (such as diethylene glycol dibenzoate and pentaerythritol ester); aliphatic esters (such as butyl oleate and methyl acetylricinoleate); phosphoric acid esters (such as tricresyl phosphate, trioctyl phosphate, and octyldiphenyl phosphate); epoxy plasticizers (such as epoxidated soybean oil, epoxidated linseed oil, and benzyl epoxystearate); polyester plasticizers (such as polyesters of dibasic acid and a divalent alcohol); polyethers (such as polypropylene glycol and its derivatives); polystyrenes (such as poly-α-methylstyrene and polystyrene); polybutadiene butadiene-acrylonitrile copolymer; polychloroprene; polyisoprene; polybutene; chlorinated paraffins; benzoic esters; glycol esters; phosphoric esters; sulfonic esters; and mixtures thereof, wherein any given compound is different than an ingredient otherwise included in the composition of the invention.

In addition, high-molecular weight plasticizers can also be used. Specific examples of such high-molecular weight plasticizer include, but are not limited to, vinyl polymers obtainable by polymerizing a vinyl monomer by various methods; polyalkylene glycol esters such as diethyl ene glycol dibenzoate, triethylene glycol dibenzoate and pentaerythritol esters; polyester plasticizers obtainable from a dibasic acid, such as sebacic acid, adipic acid, azelaic acid or phthalic acid, and a dihydric alcohol, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol or dipropylene glycol; polyethers such as polyether polyols, e.g. polyethylene glycol, polypropylene glycol and polytetramethylene glycol that have a molecular weight of 500 or more, and even further 1,000 or more, and derivatives of these as obtainable by converting the hydroxyl groups of these polyether polyols to an ester, ether or the like groups; polystyrenes such as polystyrene and poly-α-methylstyrene; polybutadiene, polybutene, polyisobutylene, butadiene-acrylonitrile, polychloroprene and the like. In one or more specific embodiments, plasticizers include propylene glycol dibenzoate, diisononyl phthalate, and soy methyl esters, Mesamol II, HB-40, butylbenzylphthalate. In other specific embodiments, the plasticizers employed are phthalic acid esters. In one or more embodiments, the plasticizers may include high boiling solvents that promote tackification, lowering of viscosity, and sprayability.

In one or more embodiments, a moisture scavenger is employed in the adhesive compositions of this invention. Moisture scavengers that may be employed include chemical moisture scavengers and physical moisture scavengers that absorb and/or adsorb moisture. In particular embodiments, the chemical moisture scavenger is vinyl-trimethoxysilane, which may be employed in an amount of up to about 3% by weight based on the total weight of the adhesive composition. An example of a physical moisture scavenger that may be employed is 3A Sieves from UOP, which is a zeolite having 3 Angstrom pores capable of trapping moisture. Other moisture scavengers that may be employed include oxazoladines and calcium oxide.

In one or more embodiments, suitable thixotropic agents may include, but are not limited to, polyvinylpyrrolidone, titanate coupling agents, metal soaps (such as calcium stearate, aluminum stearate, and barium stearate, aluminum distearate, and aluminum tristearate), copolymers with acidic groups, compounds having ionic groups, fumed silica, colloidal silica, asbestine, organic derivatives of castor oil (such as hydrogenated castor oil derivatives), treated clays, organic bentonite, modified polyester polyols (such as polyoxyethylene-polyoxypropylene block copolymers), aliphatic amides, and polyamides (such as polyamide waxes). Specific examples include polyamide waxes, such as “Crayvallac SLX” available from Arkema, or polymerized castor oils such as Flowtone R from Crayvalley.

Antioxidants that may be employed if desired. Examples of useful antioxidants include hindered phenols and phosphate esters.

Generally, any compatible filler, such as calcium carbonate may be employed if desired for a particular application. As the skilled person will appreciate, fillers will generally be omitted when the adhesive composition is intended to be sprayed onto one surface that is subsequently applied to a second surface on which the adhesive is or is not deposited.

As mentioned above, the adhesive composition may include one or more catalysts for the purpose of promoting the crosslinking the silane-terminated polymer. Without wishing to be bound by any particular theory, it is believed that these catalysts promote the hydrolysis and condensation of organosilicon compounds (i.e., reactions between the terminal groups of the polymer having silicon-containing hydrolyzable terminal groups, and reactions between the optional adhesion promoter when present and the polymer having silicon-containing hydrolyzable terminal groups). In one or more embodiments, hydrolysis of organosilicon compounds may be catalyzed by either acids or bases. Useful basic catalysts that may be employed in the compositions of this invention include alkali metal hydroxides such as potassium hydroxide, silanolates such as lithium silanolate, organic amines, and Lewis bases such as alkali metal carbonates and bicarbonates. Suitable acid catalysts include mineral acids such as sulfuric and phosphoric acids, organic acids such as acetic, propanoic and methane sulfonic acids. Other suitable acid catalysts include Lewis acids such as aluminum chloride, organotin compounds such as dibutyl tin dilaurate and titanium compounds such as the alkyl ortho esters, including tetrabutyl titanate.