Adhesive composition with improved thermal stability

Abstract

The invention relates to an adhesive composition containing: a) a styrene block copolymer component SC, b) at least one tackifying resin TR, and c) at least one thermoplastic resin TP and / or at least one polyolefin wax PW wherein the styrene block copolymer component SC comprises at least one styrene isoprene styrene (SIS) triblock copolymer SC1, the polystyrene content is at least 25% by weight, preferably at least 35% by weight, and / or the diblock content is not more than 10% by weight, preferably not more than 5% by weight.

Description

Technical Field

[0001] This invention relates to adhesive compositions, particularly adhesives comprising styrene block copolymers, and to the use of such adhesives in providing adhesive articles such as condensation control membranes. Background of the Invention

[0002] Pressure-sensitive adhesives (PSAs) are viscoelastic materials that adhere instantly to virtually any type of substrate upon application of light pressure and are permanently tacky. PSAs applied as a melt (also known as hot-melt pressure-sensitive adhesives (HM-PSAs)) have the advantage of an infinitely long open time, making them suitable for bonding large surfaces with thin adhesive films. These types of adhesives are also suitable for lamination applications involving long waiting times without requiring reactivation of the applied adhesive layer through heating. Due to the permanent tack of the adhesive material, pre-applied PSA layers are typically covered with release linings to prevent unwanted bonding and protect the adhesive layer from contamination.

[0003] Adhesive articles comprising a carrier layer and a pressure-sensitive adhesive layer (which are typically stored and transported in rolls, such as adhesive tapes and self-adhesive films) may or may not have a release liner. Whether a release liner is required depends on the nature of the carrier layer, particularly whether the adhesive article can be unrolled from the roll without the back of the carrier layer adhering to the adhesive layer and complicating the use of the adhesive article.

[0004] Self-adhesive articles comprising a monolithic polymer or metal carrier layer can typically be supplied in rolls without a release liner. However, adhesive articles comprising a fabric-based carrier layer, especially those containing loose or needle-punched fibers, are practically impossible to supply in rolls without a release liner. The most significant disadvantage associated with using a release liner is that it increases the production cost of the adhesive article and increases waste, as the release liner must be removed before use.

[0005] Another drawback of pressure-sensitive adhesives is that they may exhibit low thermal stability, making them unsuitable for applications where the adhesive product is exposed to high temperatures, especially if the temperature fluctuates regularly between two extremes. An example of such an application is bonding membranes (e.g., condensation control membranes) to metal roofs, where the roof temperature can rise to 100°C during the day in hot climates and cool to sub-zero levels at night.

[0006] Condensation control membranes (also known as moisture control membranes) are commonly used to prevent water from condensing on the lower surface of metal roofs and subsequently forming and dripping water droplets. These types of membranes are typically composed of fibrous materials that effectively absorb moisture and thus prevent the formation of water droplets through condensation. Condensation control membranes typically have a pressure-sensitive adhesive layer to allow for easy application to metal roofs. Due to the adhesive's tackiness and the use of a fibrous-based material as a carrier layer, the adhesive layer is covered with a release liner to prevent premature unwanted adhesion and to allow the membrane to be supplied in rolls.

[0007] Therefore, there is a need for a novel adhesive composition that exhibits good thermal stability and can be used to provide adhesive articles containing a fiber-based carrier layer, such as a condensation control membrane, without the use of a release liner. Summary of the Invention

[0008] The object of the present invention is to provide an adhesive composition that enables the provision of an adhesive article having a fiber-based carrier layer and an adhesive composition layer, wherein even if the adhesive article is provided in roll form, the adhesive layer does not necessarily need to be covered with a release liner.

[0009] Surprisingly, it has been found that this objective can be achieved by the features of claim 1.

[0010] Specifically, according to the present invention, an adhesive composition is provided, the adhesive composition comprising:

[0011] a) Styrene block copolymer component SC,

[0012] b) At least one tackifying resin TR, and

[0013] c) At least one thermoplastic resin TP and / or at least one polyolefin wax PW,

[0014] The styrene block copolymer component SC comprises at least one styrene block copolymer SC1, which has a polystyrene content of at least 25% by weight, preferably at least 30% by weight, and a diblock content of no more than 10% by weight, preferably no more than 5% by weight.

[0015] The results show that the proposed adhesive composition exhibits excellent thermal stability, making it particularly suitable for bonding condensation control membranes comprising a fiber-based carrier layer to the surface of metal roofs. Furthermore, the proposed adhesive composition has very low tackiness at normal room temperature, enabling the provision of condensation control membranes without the use of release liner. However, the tackiness of the adhesive layer can be restored by heating, thus facilitating easy application of the membrane to the metal roof.

[0016] Other aspects of the invention are described below and are the subject of the other independent claims. Particularly preferred embodiments are outlined throughout the specification and dependent claims. Detailed Implementation

[0017] The subject of this invention is an adhesive composition comprising:

[0018] a) Styrene block copolymer component SC,

[0019] b) At least one tackifying resin TR, and

[0020] c) At least one thermoplastic resin TP and / or at least one polyolefin wax PW,

[0021] The styrene block copolymer component SC comprises at least one styrene block copolymer SC1, which has a polystyrene content of at least 25% by weight, preferably at least 30% by weight, and a diblock content of no more than 10% by weight, preferably no more than 5% by weight.

[0022] The term "polymer" refers to a collection of chemically homogeneous macromolecules produced by polymerization reactions (addition polymerization, addition polymerization, condensation polymerization), wherein the macromolecules differ in their degree of polymerization, molecular weight, and chain length. The term also includes derivatives of the collection of said macromolecules produced by polymerization reactions, i.e., compounds obtained by addition or substitution reactions of functional groups in a predetermined macromolecule, which may be chemically homogeneous or chemically heterogeneous.

[0023] The term "molecular weight" refers to the molar mass (g / mol) of a molecule or a portion of a molecule (also called a "part"). The term "average molecular weight" refers to the number-average molecular weight (Mn) or weight-average molecular weight (Mw) of a mixture of oligomers or polymers of molecules or parts. Molecular weight can be determined by conventional methods, preferably by gel permeation chromatography (GPC) using polystyrene as a standard, styrene-divinylbenzene gels with porosities of 100 Å, 1000 Å, and 10000 Å as columns, and depending on the molecules, using tetrahydrofuran as a solvent at 35 °C or 1,2,4-trichlorobenzene as a solvent at 160 °C.

[0024] The term "melting temperature" refers to the temperature at which a material undergoes a transition from a solid to a liquid state. The melting temperature (Tm) is preferably determined by differential scanning calorimetry (DSC) according to ISO 11357-3 using a heating rate of 2 °C / min. Measurements can be performed using a Mettler Toledo DSC 3+ apparatus, and the Tm value can be determined from the measured DSC curve using DSC software. In cases where the measured DSC curve displays several peak temperatures, the first peak temperature from the lower temperature side of the thermogram is taken as the melting temperature (Tm).

[0025] The term "softening point" or "softening temperature" refers to the temperature at which a compound softens in a rubbery state, or the temperature at which the crystalline portion of a compound melts. The softening point can be measured using the ring and ball method according to EN 1238:2011.

[0026] The term "glass transition temperature" (Tg) refers to the temperature at which a polymer component becomes soft and flexible above it and hard and glassy below it. The glass transition temperature (Tg) is preferably determined by dynamic mechanical analysis (DMA), which is the peak value of the loss modulus (G″) curve measured using an applied frequency of 1 Hz and a strain level of 0.1%.

[0027] The term "amount or content of at least one component X" in a composition, such as "amount of at least one styrene block copolymer," refers to the sum of the individual amounts of all styrene block copolymers contained in the composition. For example, if the composition contains 20% by weight of at least one styrene block copolymer, the sum of the amounts of all styrene block copolymers contained in the composition equals 20% by weight.

[0028] The adhesive composition contains a styrene block copolymer component SC as a first essential component.

[0029] Suitable styrene block copolymers for use as the styrene block copolymer component SC include, in particular, block copolymers containing polystyrene and polybutadiene blocks and / or polyisoprene blocks. These materials are generally available as pure triblock copolymers (also known as SIS and SBS block copolymers) and as diblock copolymers (SI and SB block copolymers). Furthermore, styrene block copolymers are also commercially available as mixtures of diblock and triblock copolymers. Suitable styrene block copolymers can have linear, radial, or star-shaped structures, with linear structures being particularly preferred.

[0030] Suitable SI, SIS, SB and SBS block copolymers are commercially available, for example from TSRC / Dexco under the trade name Vector® (such as the Vector® 4000 series), and from KratonPolymers under the trade name Kraton® D series.

[0031] According to the present invention, the styrene block copolymer component SC comprises at least one styrene block copolymer SC1, wherein the polystyrene content is at least 25% by weight, preferably at least 30% by weight, more preferably at least 35% by weight, and the diblock content is not more than 10% by weight, preferably not more than 5% by weight, more preferably not more than 1.5% by weight.

[0032] The term "polystyrene content of block copolymer" in this disclosure refers to the weight percentage of styrene or polystyrene in the block copolymer and is based on the total weight of the block copolymer, while the term "diblock content" refers to the amount of SI-diblocks in the styrene block copolymer.

[0033] In one or more embodiments, at least one styrene block copolymer SC1 is a styrene-isoprene-styrene (SIS) triblock copolymer or a styrene-butadiene-styrene (SBS) triblock copolymer, preferably a styrene-isoprene-styrene (SIS) triblock copolymer.

[0034] The adhesive composition may particularly contain 5-45% by weight, preferably 10-40% by weight, more preferably 15-35% by weight, or even more preferably 20-30% by weight, of at least one styrene-isoprene-styrene (SIS) triblock copolymer SC1.

[0035] In one or more embodiments, the adhesive composition comprises 10-60% by weight, preferably 15-55% by weight, more preferably 20-50% by weight, and even more preferably 25-45% by weight of at least one styrene block copolymer SC.

[0036] Preferably, in addition to at least one styrene block copolymer SC1, the styrene block copolymer component SC also includes other styrene block copolymers.

[0037] In one or more embodiments, the styrene block copolymer component SC further comprises at least one styrene block copolymer SC2, having a styrene content of not more than 35% by weight, preferably not more than 30% by weight, more preferably not more than 25% by weight, and a diblock content of not more than 10% by weight, preferably not more than 5% by weight, more preferably not more than 1.5% by weight.

[0038] In one or more embodiments, at least one styrene block copolymer SC2 is a styrene-isoprene-styrene (SIS) triblock copolymer or a styrene-butadiene-styrene (SBS) triblock copolymer, preferably a styrene-isoprene-styrene (SIS) triblock copolymer.

[0039] In particular, the adhesive composition contains 0.5-25% by weight, preferably 1.5-20% by weight, more preferably 2.5-15% by weight, and even more preferably 3.5-12.5% ​​by weight of at least one styrene block copolymer SC2.

[0040] Styrene block copolymers with high diblock content are also suitable for adhesive compositions. However, it has been found that the use of large amounts of such styrene block copolymers leads to an increase in the tackiness of the adhesive composition, which hinders the provision of adhesive articles in roll form without the use of release liner.

[0041] Therefore, it is preferable that the adhesive composition contains no more than 15% by weight, preferably no more than 10% by weight, more preferably no more than 5% by weight, or even more preferably no more than 2.5% by weight of a styrene block copolymer having a diblock content of at least 15% by weight, preferably at least 10% by weight, more preferably at least 5% by weight, or even more preferably at least 2.5% by weight.

[0042] In one or more embodiments, the adhesive composition comprises no more than 15% by weight, preferably no more than 10% by weight, more preferably no more than 5% by weight, and even more preferably no more than 2.5% by weight of a styrene block copolymer with a diblock content of 15% by weight or higher.

[0043] In one or more further embodiments, the adhesive composition comprises no more than 15% by weight, preferably no more than 10% by weight, more preferably no more than 5% by weight, or even more preferably no more than 2.5% by weight of a styrene block copolymer with a diblock content of 10% by weight or higher.

[0044] In one or more other embodiments, the adhesive composition comprises no more than 15% by weight, preferably no more than 10% by weight, more preferably no more than 5% by weight, or even more preferably no more than 2.5% by weight of a styrene block copolymer with a diblock content of 5% by weight or higher.

[0045] In one or more other embodiments, the adhesive composition comprises no more than 15% by weight, preferably no more than 10% by weight, more preferably no more than 5% by weight, or even more preferably no more than 2.5% by weight of a diblock copolymer with a content of 2.5% by weight or higher.

[0046] The adhesive composition contains at least one tackifying resin TR as a second essential component.

[0047] The term "tackifying resin" herein refers to a resin that generally enhances the adhesiveness and / or tackiness of an adhesive composition. The term "tackiness" herein refers to the property of a substance to be tacky or adhesive upon simple contact. Tackiness can be measured, for example, as ring tack. Preferred tackifying resins are tackifying at a temperature of 25°C.

[0048] Examples of suitable tackifying resins include natural resins, synthetic resins, and chemically modified natural resins.

[0049] Examples of suitable natural resins and chemically modified natural resins include rosin, rosin esters, phenol-modified rosin esters, and terpene resins. The term "rosin" should be understood to include rosin resins, wood rosin resins, tall oil rosin resins, distilled rosin resins, and modified rosin resins, such as any dimerized, hydrogenated, maleized, and / or polymerized forms of these rosins.

[0050] Suitable terpene resins include copolymers and terpolymers of natural terpenes, such as styrene / terpene and α-methylstyrene / terpene resins; polyterpene resins, typically obtained by polymerization of terpenes such as bicyclic monoterpenes called pinene at moderate low temperatures in the presence of Friedel-Crafts catalysts; hydrogenated polyterpene resins; and phenol-modified terpene resins, including their hydrogenated derivatives.

[0051] The term "synthetic resin" refers to a compound obtained by controlled chemical reactions, such as addition polymerization or condensation polymerization, between well-defined reactants that do not themselves possess resin properties.

[0052] Monomers polymerizable to synthesize synthetic resins may include aliphatic monomers, alicyclic monomers, aromatic monomers, or mixtures thereof. Aliphatic monomers may include C4, C5, and C6 alkanes, alkenes, and conjugated dienes. Examples of aliphatic or alicyclic monomers include butadiene, isobutene, 1,3-pentadiene, 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, dicyclopentadiene, and terpenes. Aromatic monomers may include C8, C9, and C6 alkanes. 10 Aromatic monomers. Examples of aromatic monomers include styrene, indene, styrene derivatives, indene derivatives, coumarones, and combinations thereof.

[0053] Particularly suitable synthetic resins include those prepared by polymerization of mixtures of unsaturated monomers obtained as byproducts of cracked natural gas liquids, gas oils, or naphtha. Such synthetic resins obtained from petroleum-based feedstocks are also characterized as "petroleum resins" or "hydrocarbon resins." These also include pure monomeric aromatic resins prepared from aromatic monomer feedstocks that have been purified by polymerization to remove color-causing contaminants and precisely control the composition of the product. Thickening hydrocarbon resins typically have relatively low average molecular weights (Mn), for example in the range of 250-5000 g / mol, and glass transition temperatures above 0°C, preferably equal to or higher than 15°C, more preferably equal to or higher than 30°C.

[0054] Examples of suitable hydrocarbon resins for use as tackifying resins (TR) include, for example, C5 aliphatic hydrocarbon resins, mixed C5 / C9 aliphatic / aromatic hydrocarbon resins, aromatically modified C5 aliphatic hydrocarbon resins, alicyclic hydrocarbon resins, mixed C5 aliphatic / alicyclic hydrocarbon resins, mixed C9 aromatic / alicyclic hydrocarbon resins, mixed C5 aliphatic / alicyclic / C9 aromatic hydrocarbon resins, aromatically modified alicyclic hydrocarbon resins, C9 aromatic hydrocarbon resins, polyterpene resins, copolymers and terpolymers of natural terpenes, and hydrogenated forms of the aforementioned hydrocarbon resins. The symbols “C5” and “C9” indicate that the monomers used to prepare the resin are primarily hydrocarbons having 4-6 and 8-10 carbon atoms, respectively. The term “hydrogenated” includes fully, substantially, and at least partially hydrogenated resins. Partially hydrogenated resins may have, for example, hydrogenation levels of 50%, 70%, or 90%.

[0055] Preferably, at least one tackifying resin TR is a non-functionalized tackifying resin. The term "non-functionalized tackifying resin" refers to a tackifying resin that has not been chemically modified to contain functional groups such as epoxy, silane, sulfonate, amide, or anhydride groups.

[0056] In particular, at least one tackifying resin has a softening point of not more than 150°C, preferably not more than 135°C, as determined by the ring and ball method according to EN 1238:2011.

[0057] In one or more embodiments, at least one tackifying resin TR has:

[0058] - The softening point measured by the ring and ball method according to EN 1238:2011 in the range of 65-150°C, preferably 70-140°C, more preferably 75-130°C, and even more preferably 80-120°C, within the range of 65-150°C, preferably 70-140°C, even more preferably 75-130°C, and even more preferably 80-120°C.

[0059] - A number-average molecular weight (Mn) in the range of 150-5000 g / mol, preferably 250-4000 g / mol, more preferably 250-3500 g / mol, and even more preferably 250-3000 g / mol, and / or

[0060] - A glass transition temperature (Tg) equal to or higher than 0°C, preferably equal to or higher than 10°C, more preferably equal to or higher than 20°C, and even more preferably equal to or higher than 30°C, which is determined by dynamic mechanical analysis (DMA) as the peak of the loss modulus (G”) curve measured using an applied frequency of 1 Hz and a strain level of 0.1%.

[0061] Suitable hydrocarbon resins are available commercially, for example, under the trade names Wingtack® series, Wingtack® Plus, Wingtack® Extra and Wingtack® STS (all from Cray Valley); under the trade names Escorez® 1000 series, Escorez® 2000 series and Escorez® 5000 series (all from Exxon Mobile Chemical); under the trade names Novares® T series, Novares® TT series, Novares® TD series, Novares® TL series, Novares® TN series, Novares® TK series and Novares® TV series (all from RÜTGERS Novares GmbH); and under the trade names Kristalex®, Plastolyn®, Piccotex®, Piccolastic® and Endex® (all from Eastman Chemicals).

[0062] In one or more embodiments, the adhesive composition comprises 30-70% by weight, preferably 35-65% by weight, more preferably 40-60% by weight, and even more preferably 45-60% by weight, at least one tackifying resin TR.

[0063] The adhesive composition also comprises at least one thermoplastic resin TP and / or at least one polyolefin wax PW. In particular, the thermoplastic resin TP is different from the tackifying resin TR.

[0064] Preferably, at least one thermoplastic resin TP is a nonfunctionalized hydrocarbon resin.

[0065] In one or more embodiments, at least one thermoplastic resin TP has:

[0066] - The softening point is measured by the ring and ball method according to EN 1238:2011, which is equal to or higher than 115°C, preferably equal to or higher than 120°C, more preferably equal to or higher than 125°C, and even more preferably equal to or higher than 130°C, and / or

[0067] - A number-average molecular weight (Mn) in the range of 500-5000 g / mol, preferably 750-4500 g / mol, more preferably 1000-4000 g / mol, and even more preferably 1250-3500 g / mol, and / or

[0068] - The glass transition temperature (Tg) was determined by differential scanning calorimetry (DSC) at a heating rate of 20 °C / min, and was 15 °C or higher, preferably 35 °C or higher, more preferably 55 °C or higher, and even more preferably 75 °C or higher.

[0069] The term "polyolefin wax" herein refers to low molecular weight polymers of straight-chain or branched α-olefins having 2-30 carbon atoms and an average molecular weight (Mn) in the range of 5000-25000 g / mol. These include homopolymers and copolymers of the aforementioned straight-chain or branched α-olefins.

[0070] Suitable polyolefin waxes can be obtained through the thermal decomposition of polyolefin plastics, particularly polyethylene plastics, or through the direct polymerization of olefins. Suitable polymerization methods include, for example, free radical methods in which olefins (such as ethylene) are reacted under high pressure and high temperature to obtain more or less branched waxes, and methods in which ethylene and / or higher α-olefins (especially propylene) are polymerized using organometallic catalysts (such as Ziegler-Natta or metallocene catalysts) to obtain unbranched or branched waxes. Polyolefin waxes typically have a structure that is at least partially crystalline.

[0071] In particular, at least one polyolefin wax PW has:

[0072] -The softening point measured by the ring and ball method according to EN 1238:2011 is 100°C or above, preferably 115°C or above, more preferably 125°C or above, and even more preferably 135°C or above, and / or

[0073] - 0.90-0.96 g / cm³ measured at 23°C according to ISO 1183-1:2019 standard. 3 The preferred concentration is 0.91-0.95 g / cm³. 3 More preferably 0.92-0.94cm 3 density, and / or

[0074] - Melt viscosity measured at 170°C according to DIN 53019 standard, in the range of 10-10000 mPa·s, preferably 100-5000 mPa·s, more preferably 500-3500 mPa·s.

[0075] In one or more embodiments, at least one polyolefin wax PW is a polar-modified polyolefin wax.

[0076] Suitable polar modified polyolefin waxes include waxes obtained by grafting polar olefin monomers, such as α-β-unsaturated carboxylic acids and / or their derivatives, such as (meth)acrylic acid or maleic anhydride and / or substituted and / or unsubstituted styrene, onto polyolefin waxes.

[0077] In one or more embodiments, at least one polyolefin wax PW is a maleic anhydride-functionalized polyolefin wax, preferably a maleic anhydride-grafted polyolefin wax.

[0078] Particularly suitable maleic anhydride-grafted polyolefin waxes have a maleic anhydride grafting degree of at least 1% by weight, for example, at least 3% by weight.

[0079] In one or more embodiments, at least one polyolefin wax PW is a maleic anhydride-grafted polyolefin wax having a maleic anhydride grafting degree of 2-15% by weight, preferably 4-15% by weight, more preferably 5-12% by weight.

[0080] The term "grafting degree" in this disclosure refers to the ratio of polymeric groups in the side chain to the polymer constituting the main chain of the grafted compound, expressed as a weight percentage. Therefore, the term "maleic anhydride grafting degree" herein refers to the ratio of maleic anhydride groups in the side chain to the polymer constituting the main chain of the grafted polyolefin wax, expressed as a weight percentage.

[0081] In one or more embodiments, at least one polyolefin wax is selected from ethylene and propylene homopolymer and copolymer waxes grafted with maleic anhydride, more preferably from polypropylene and polyethylene waxes grafted with maleic anhydride.

[0082] In one or more preferred embodiments, the at least one polyolefin wax PW is a maleic anhydride-grafted polypropylene wax.

[0083] In particular, the total amount of at least one thermoplastic resin TP and at least one polyolefin wax PW accounts for 2.5-35% by weight, preferably 5-30% by weight, more preferably 5-25% by weight, and even more preferably 10-20% by weight of the total weight of the adhesive composition.

[0084] In addition to the compounds described above, the adhesive composition may contain other auxiliary substances and additives, such as those selected from UV absorbers, UV and heat stabilizers, flame retardants, fillers, optical brighteners, antioxidants, pigments, dyes, and drying agents. Exemplary UV stabilizers that may be included in the adhesive composition include, for example, sterically hindered phenols. However, the total amount of these additional auxiliary substances and additives preferably constitutes no more than 15% by weight, more preferably no more than 10% by weight, and even more preferably no more than 5% by weight of the total weight of the adhesive composition.

[0085] In one or more embodiments, the adhesive composition has a blocking value of no more than 20 N / 50 mm, preferably no more than 15 N / 50 mm, as measured according to the method defined below.

[0086] Measurement of adhesion value

[0087] First, a film approximately 50 mm wide was prepared from a test adhesive composition with a thickness of 50 μm. The adhesive film was then placed between two nonwoven materials measuring 150 × 50 mm (length, width). The composite element was then placed in an oven at 50°C for 24 hours, weighing 500 g.

[0088] Adhesive behavior was measured using a standard universal testing machine at a test speed of 300 mm / min. The average tensile strength obtained during the peeling of 5 cm long nonwoven strips from each other at an angle of 180° was recorded as the “adhesive value” of the tested adhesive composition.

[0089] The adhesive composition can be prepared by mixing its components at a temperature of 140-220°C, preferably 160-200°C, until a homogeneous mixture is obtained. Any conventional mixing technique known to those skilled in the art can be used. Preferably, mixing is performed by a kneading process. Components a) to c) can be added to the mixer in any order. Preferably, the styrene block copolymer SC is first mixed with the tackifying resin TR until a homogeneous mixture is obtained. The remaining components can be added to the homogeneous mixture of a) and b) in any order.

[0090] Unless otherwise stated, the preferred embodiments described above for at least one styrene block copolymer SC, at least one tackifying resin TR, at least one thermoplastic resin TP, and at least one polyolefin wax PW are applicable to all other aspects of the invention.

[0091] Another aspect of the present invention is an adhesive article, such as a condensation control membrane, comprising:

[0092] i) A fiber material layer having an upper main surface and a lower main surface, and

[0093] ii) An adhesive layer covering at least a portion of one of the main surfaces of the fibrous material layer.

[0094] The adhesive layer comprises:

[0095] a) Styrene block copolymer component SC,

[0096] b) At least one tackifying resin TR,

[0097] c) At least one thermoplastic resin TP and / or at least one polyolefin wax PW,

[0098] Furthermore, the styrene block copolymer component SC comprises at least one styrene block copolymer SC1, which has a polystyrene content of at least 25% by weight, preferably at least 30% by weight, and a diblock content of no more than 10% by weight, preferably no more than 5% by weight.

[0099] According to one or more embodiments, the adhesive layer comprises or is composed of an adhesive composition according to the invention.

[0100] Specifically, the adhesive layer has a strength of at least 20 g / m². 2 Preferably at least 40g / m 2 More preferably at least 50g / m 2 and / or no more than 500g / m 2 Preferably not greater than 400g / m 2 More preferably, not more than 300g / m 2 The coating weight.

[0101] The adhesive layer can exist on the fibrous material layer in the form of a continuous or discontinuous adhesive layer. The term "continuous adhesive layer" here refers to a layer consisting of a single area coated with an adhesive composition, while the term "discontinuous adhesive layer" refers to a layer consisting of two or more areas coated with an adhesive composition, which are not connected to each other to form a continuous layer.

[0102] Preferably, the fibrous material layer comprises synthetic organic and / or inorganic fibers.

[0103] Suitable synthetic organic fibers include, for example, polyester fibers, polypropylene fibers, polyethylene fibers, nylon fibers and polyamide fibers, while suitable inorganic fibers include, for example, glass fibers, aramid fibers, wollastonite fibers and carbon fibers.

[0104] In one or more embodiments, the fibrous material layer is a nonwoven fabric, preferably comprising synthetic organic fibers or inorganic fibers, and preferably having a density of at least 35 g / m². 2 More preferably at least 50g / m 2 Or even more preferably at least 65g / m 2 and / or no more than 350g / m 2 More preferably not greater than 300g / m 2 Or even more preferably no more than 250g / m 2 Mass per unit area.

[0105] In one or more preferred embodiments, the fiber material layer is a nonwoven fabric comprising polyester fibers, preferably having a density of 35-300 g / m². 2 More preferably 50-250g / m 2 , or even more preferably 65-200g / m 2 Mass per unit area.

[0106] In one or more further preferred embodiments, the fiber material layer is a nonwoven fabric comprising glass fibers, preferably having a density of 35-300 g / m². 2 More preferably 50-250g / m 2 Even better, 65-200g / m 2 Mass per unit area.

[0107] In this disclosure, the term "nonwoven fabric" refers to a material composed of fibers bonded together by chemical, mechanical, or thermal bonding methods, and which is neither woven nor braided. Nonwoven fabrics can be produced, for example, by using carding or needle-punching processes, in which the fibers are mechanically entangled to obtain the nonwoven fabric. In chemical bonding, chemical adhesives such as bonding materials are used to hold the fibers together in the nonwoven fabric.

[0108] In one or more embodiments, the outer surface of the adhesive layer away from the fibrous material layer does not become sticky when at a temperature of 23°C or below, preferably 30°C or below, more preferably 35°C or below.

[0109] In particular, the outer surface of the adhesive layer away from the fiber material layer has an annular initial tack with steel of no more than 2.5 N / 2.5 cm, preferably no more than 1.5 N / 2.5 cm, and more preferably no more than 1 N / 2.5 cm, as measured at 23°C by using the method described below.

[0110] Ring-shaped initial viscosity measurement

[0111] The ring tack of the adhesive was tested according to the method "FTM 9-Loop Tack Measurement". To measure the ring tack, a sample strip with a width of 25 mm and a length of approximately 200 mm was first coated with the test adhesive with a coating thickness of 100 μm. The sample strip was then formed into a loop and brought into contact with a steel plate moving at a constant speed of 300 mm / min. Once a contact area of ​​25 mm × 25 mm was achieved, the loop was removed, and the force required to separate the loop from the steel plate was recorded as the ring tack value.

[0112] Due to the low tack of the adhesive layer, condensation control films can be supplied without release linings, especially in roll form.

[0113] The adhesive articles of the present invention, such as condensation control membranes, can be prepared using any conventional adhesive lamination techniques known to those skilled in the art. The adhesive composition can be applied as a melt to the surface of the fibrous material layer using techniques such as slot die coating, roller coating, curtain coating, or spray coating.

[0114] Another aspect of the present invention is the use of the adhesive product of the present invention as a condensation control membrane.

[0115] In one or more embodiments, the fibrous material layer of the adhesive article is a nonwoven fabric comprising synthetic organic fibers, preferably selected from polyester fibers, polypropylene fibers, polyethylene fibers, nylon fibers, and polyamide fibers.

[0116] Another aspect of the invention is a composite metal roofing panel comprising a metal plate having upper and lower main surfaces and an adhesive article according to the invention bonded to one of the main surfaces of the metal plate by an adhesive layer.

[0117] In one or more embodiments, the fibrous material layer of the adhesive article present in the composite metal roof panel is a nonwoven fabric comprising synthetic organic fibers, preferably selected from polyester fibers, polypropylene fibers, polyethylene fibers, nylon fibers, and polyamide fibers.

[0118] Metal roofing panels are preferred. Typical metals used for these panels include, for example, galvalume, aluminum, zinc, copper, and stainless steel. The thickness of the metal roofing panels is typically at least 0.15 mm, for example at least 0.25 mm, especially at least 0.35 mm and not more than 250 mm, especially not more than 1.5 mm, while the width can be at least 0.25 m, for example at least 0.35 m, especially at least 0.5 m and not more than 3 m, especially not more than 2 m.

[0119] In addition, metal roofing panels can have a flat surface or a corrugated surface with continuous peaks and valleys.

[0120] Another aspect of the present invention is a composite insulation board comprising an insulation board having an upper main surface and a lower main surface, and an adhesive article of the present invention adhered to at least one main surface of the insulation board by an adhesive layer.

[0121] In one or more embodiments, the insulation board is a glass wool board. The term "glass wool board" in this disclosure refers to an insulation board made of glass fiber.

[0122] In one or more other embodiments, the separator is a foam board, preferably selected from molded expanded polystyrene (EPS) foam board, extruded expanded polystyrene (XPS) foam board, polyurethane foam board (PUR) and polyisocyanurate (PIR) foam board, particularly having a density of 10-100 g / l, more preferably 15-85 g / l.

[0123] In particular, the fibrous material layer of the adhesive product present in the composite insulation board is a nonwoven fabric containing inorganic fibers, preferably selected from glass fibers, aramid fibers, wollastonite fibers and carbon fibers, especially glass fibers, particularly glass fiber mats.

[0124] Composite panels can be used as, for example, ceiling insulation panels, wall insulation panels or roof insulation panels.

[0125] Another aspect of the present invention is a method for preparing a composite metal roofing panel or a composite insulation panel, the method comprising the following steps:

[0126] I) Provides the adhesive article of the present invention,

[0127] II) Heat the adhesive layer to an elevated temperature, and

[0128] III) The heated adhesive layer is brought into contact with the surface of the metal sheet or the surface of the heat insulation board, and sufficient pressure is applied to achieve adhesive bonding between the adhesive product and the metal sheet or between the adhesive product and the heat insulation board;

[0129] or

[0130] I') Provides a hot melt adhesive composition,

[0131] II') Apply the hot melt adhesive composition as a melt to the surface of a metal sheet or a heat insulation board to provide an adhesive layer.

[0132] III') Make the adhesive layer contact the fiber material layer, and

[0133] IV') Cool and cure the adhesive layer to achieve bonding between the fiber material layer and the metal sheet or between the fiber material layer and the insulation board.

[0134] The hot melt adhesive composition comprises:

[0135] a) At least one styrene block copolymer SC,

[0136] b) At least one tackifying resin TR,

[0137] c) At least one thermoplastic resin TP and / or at least one polyolefin wax PW,

[0138] Furthermore, at least one of the styrene block copolymers SC is selected from styrene isoprene diblock (SI) copolymer, styrene isoprene triblock (SIS) copolymer, styrene-butadiene diblock (SB) copolymer, and styrene-butadiene triblock (SBS) copolymer.

[0139] In step II) of this method, the temperature at which the adhesive layer is heated depends on the implementation of the adhesive.

[0140] Specifically, in step II), the adhesive layer is heated to a temperature of 85°C or higher, preferably 100°C or higher, more preferably 110°C or higher and / or not higher than 170°C, preferably not higher than 160°C, more preferably not higher than 150°C.

[0141] In one or more embodiments, in step II), the adhesive layer is heated to a temperature of 95-150°C, preferably 100-140°C, and more preferably 105-130°C.

[0142] The heating of the adhesive layer in step II) can be performed using any conventional techniques known to those skilled in the art, such as heating in an oven, heating by an airflow, or heating with infrared (IR) radiation.

[0143] According to one or more embodiments, the hot melt adhesive composition provided in step I') comprises or is composed of an adhesive composition according to the invention.

[0144] In one or more embodiments, the fibrous material layer of the adhesive article is a nonwoven fabric comprising synthetic organic fibers, preferably selected from polyester fibers, polypropylene fibers, polyethylene fibers, nylon fibers, and polyamide fibers.

[0145] In one or more embodiments, the insulation board is a glass wool board, and the fibrous material layer of the adhesive article is a nonwoven fabric containing inorganic fibers, preferably selected from glass fibers, aramid fibers, wollastonite fibers and carbon fibers, especially glass fibers, particularly glass fiber mats.

[0146] In one or more other embodiments, the insulation board is a foam board, preferably selected from molded expanded polystyrene (EPS) foam board, extruded expanded polystyrene (XPS) foam board, polyurethane foam board (PUR) and polyisocyanurate (PIR) foam board, particularly with a density of 10-100 g / l, more preferably 15-85 g / l, and the fibrous material layer of the adhesive article is a nonwoven fabric comprising inorganic fibers, preferably selected from glass fibers, aramid fibers, wollastonite fibers and carbon fibers, especially glass fibers, particularly glass fiber mats.

[0147] Another aspect of the invention is the use of the adhesive composition of the invention for adhering a condensation control membrane to a metal roof.

[0148] Example

[0149] The following compounds and products shown in Table 1 were used in the examples.

[0150] Table 1

[0151] Preparation of adhesive compositions

[0152] For each adhesive composition, the components as shown in Table 2 were mixed in a Sigma-kneader at 180°C. The preparation process began by mixing the styrene block copolymer, a small portion of the resin, and additives. The first mixing step was carried out under a CO2 atmosphere for 45 minutes, after which the remaining resin was added and mixed under vacuum for 30 minutes.

[0153] The adhesive compositions were stored in a siliconized box for one day and then used to characterize their properties.

[0154] Measurement methods

[0155] The adhesive composition was characterized using the following measurement methods.

[0156] Adhesion

[0157] First, a film approximately 50 mm wide was prepared from a test adhesive composition with a thickness of 50 μm. The adhesive film was then placed between two nonwoven materials measuring 150 × 50 mm (length, width). The composite element was placed in an oven at 50°C for 24 hours and weighed 500 g.

[0158] The adhesion behavior was then measured using a standard Zwick material testing machine at a test speed of 300 mm / min. The average tensile strength obtained during the peeling of 5 cm long nonwoven strips from each other at an angle of 180° was recorded as the "adhesion value".

[0159] Opening Hours

[0160] Approximately 20g of molten adhesive sample was applied to the surface of a silicone paper strip placed on a 180°C heated plate using a spatula. The silicone paper strip was 30 cm × 10 cm in size, and the adhesive was applied as a film with a thickness of 500 μm and a size of 30 cm × 6 cm. Before applying the adhesive film, the silicone paper strip and the spatula were heated to 180°C using a heated plate.

[0161] Immediately after applying the adhesive, remove the silicone paper strip from the heating plate and place it (adhesive film facing up) on the plywood sheet at room temperature (23°C), recording the time as the starting point of the measurement. Every 10 seconds, place a short strip of silicone-coated paper, measuring 10 cm × 1 cm and rolled up (non-silicone surface facing out), onto the adhesive film, then slowly remove the paper strip to separate it from the adhesive film. Repeat this process until the paper strip cannot be removed from the adhesive film without damaging the paper strip or the adhesive film. Record the time interval between the measurement start point and the last sampling point as the open time (in seconds) of the adhesive composition.

[0162] Viscosity at 190℃

[0163] Preheat the adhesive composition sample provided in the sealed tube in an oven at 190°C for 20 minutes. After heating, weigh 9.5 g of the adhesive composition sample and place it in the disposable sleeve of the viscometer. Measure the viscosity at 190°C at 5 rpm using a Brookfield DV-2 Thermosel viscometer with a No. 27 rotor. Record the values ​​obtained after tempering for 20 minutes and measuring for 5 minutes at the measurement temperature as representative viscosities.

[0164] Shear-bonded failure temperature (SAFT)

[0165] The tested adhesive composition was applied as a melt to the surface of silicone-coated paper, with a coating thickness of 100 μm. The adhesive layer was then transferred to a polyethylene terephthalate (PET) film. A sample strip approximately 70 mm long and 25 mm wide was then cut from the adhesive-coated PET film, and the adhesive layer was brought into contact with a stainless steel test plate measuring 60 × 40 mm (length, width) with a 25 mm overlap. The sample strip was rolled four times with a standard roller at a speed of approximately 10 mm / s.

[0166] The SAFT value is measured immediately after the sample strip has been rolled. At the start of the SAFT measurement, the free end of the test sample strip is folded to form a loop. The test specimen, consisting of a stainless steel test plate and the sample strip, is then vertically suspended from the free end of the stainless steel plate on a metal hook and placed in an oven preheated to 40°C. A metal weight corresponding to a static load of 500g or 1000g is attached to another metal hook, which is fixed to a clamp connected to the loop formed on the free end of the sample strip.

[0167] First, the test samples were placed in an oven at 40°C for 30 minutes. Three test samples were placed in the oven at a time for SAFT measurements. The oven temperature was then increased at a constant rate of 0.37% per minute. The temperature was increased until the adhesive bond of all test samples in the oven failed. The last measured temperature before adhesive failure was recorded as the representative thermal stability temperature. Two measurements were performed for each test adhesive composition. A third measurement was performed if the difference between the two SAFT values ​​obtained with the same adhesive composition was greater than 10°C.

[0168] The SAFT values ​​of the test adhesive compositions presented in Table 2 are obtained as the average of two measurements performed with the same adhesive composition.

[0169] Table 2

Claims

1. An adhesive composition comprising: a) Styrene block copolymer component SC, b) at least one tackifying resin TR, and c) At least one thermoplastic resin TP and / or at least one polyolefin wax PW, The styrene block copolymer component SC comprises at least one styrene block copolymer SC1, which has a polystyrene content of at least 25% by weight, preferably at least 30% by weight, and a diblock content of no more than 10% by weight, preferably no more than 5% by weight.

2. The adhesive composition according to claim 1, wherein the at least one styrene block copolymer SC1 is a styrene-isoprene-styrene (SIS) triblock copolymer or a styrene-butadiene-styrene (SBS) triblock copolymer, preferably a styrene-isoprene-styrene (SIS) triblock copolymer.

3. The adhesive composition according to any one of the preceding claims, comprising 10-35% by weight, preferably 15-30% by weight, of the at least one styrene block copolymer SC1.

4. The adhesive composition according to any one of the preceding claims, comprising 10-60% by weight, preferably 15-55% by weight, of a styrene block copolymer component SC.

5. The adhesive composition according to any one of the preceding claims, wherein the styrene block copolymer component SC further comprises at least one styrene block copolymer SC2, wherein the styrene block copolymer SC2 has a styrene content of not more than 35% by weight, preferably not more than 30% by weight, and a diblock content of not more than 10% by weight, preferably not more than 5% by weight.

6. The adhesive composition according to claim 5, wherein the at least one styrene block copolymer SC2 is a styrene-isoprene-styrene (SIS) triblock copolymer or a styrene-butadiene-styrene (SBS) triblock copolymer, preferably a styrene-isoprene-styrene (SIS) triblock copolymer.

7. The adhesive composition according to claim 5 or 6, comprising 0.5-20% by weight, preferably 2.5-15% by weight, of the at least one styrene block copolymer SC2.

8. The adhesive composition according to any one of the preceding claims, comprising no more than 15% by weight, preferably no more than 10% by weight, of a styrene block copolymer, said styrene block copolymer having a diblock content of more than 15% by weight, preferably more than 10% by weight.

9. The adhesive composition according to any one of the preceding claims, comprising 30-70% by weight, preferably 35-65% by weight, of the at least one tackifying resin TR.

10. The adhesive composition according to any one of the preceding claims, wherein the at least one thermoplastic resin TP has a softening point of 115°C or higher, preferably 120°C or higher, as determined by the ring and ball method according to EN 1238:2011, and / or the at least one polyolefin wax PW is a maleic anhydride-functionalized polyolefin wax.

11. The adhesive composition according to any one of the preceding claims, wherein the total amount of the at least one thermoplastic resin TP and the at least one polyolefin wax PW accounts for 2.5-35% by weight, preferably 5-30% by weight, of the total weight of the adhesive composition.

12. The adhesive composition according to any one of the preceding claims, wherein the adhesion value measured according to the method defined in the specification is not greater than 20 N / 50 mm, preferably not greater than 15 N / 50 mm.

13. An adhesive article comprising: i) A fiber material layer having an upper main surface and a lower main surface, and ii) An adhesive layer that at least covers a portion of one of the main surfaces of the fibrous material layer. The adhesive layer comprises: a) Styrene block copolymer component SC, b) at least one tackifying resin TR, and c) At least one thermoplastic resin TP and / or at least one polyolefin wax PW, Furthermore, the styrene block copolymer component SC comprises at least one styrene block copolymer SC1, which has a polystyrene content of at least 25% by weight, preferably at least 30% by weight, and a diblock content of no more than 10% by weight, preferably no more than 5% by weight.

14. The adhesive article of claim 13, wherein the adhesive layer comprises or is composed of an adhesive composition according to any one of claims 1-12.

15. The adhesive article according to claim 13 or 14, wherein the fibrous material layer is a nonwoven fabric, preferably comprising synthetic organic and / or inorganic fibers.

16. Use of the adhesive article according to any one of claims 13-15 as a condensation control membrane.

17. A composite metal roofing panel comprising a metal plate having an upper main surface and a lower main surface and an adhesive article according to any one of claims 13-15, the adhesive article being adhered to one of the main surfaces of the metal plate via the adhesive layer.

18. The composite metal roofing panel according to claim 17, wherein, The fibrous material layer of the adhesive article is a nonwoven fabric containing synthetic organic fibers.

19. A composite insulation panel comprising an insulation panel having an upper main surface and a lower main surface, and an adhesive article according to any one of claims 13-15, the adhesive article being adhered to at least one of the main surfaces of the insulation panel via the adhesive layer.

20. The composite insulation board according to claim 19, wherein the insulation board is a glass wool board or a foam board, preferably selected from molded expanded polystyrene (EPS) foam board, extruded expanded polystyrene (XPS) foam board, polyurethane foam board (PUR) or polyisocyanurate (PIR) foam board.

21. The composite insulation panel according to claim 19 or 20, wherein the fiber material layer of the adhesive article is a nonwoven fabric comprising inorganic fibers, preferably glass fibers.

22. A method for preparing a composite metal roofing panel or a composite insulation panel, the method comprising the following steps: I) Provide an adhesive article according to any one of claims 13-15, II) Heat the adhesive layer to an elevated temperature, and III) Bring the heated adhesive layer into contact with the surface of the metal sheet or the heat insulation board, and apply sufficient pressure to achieve adhesion between the adhesive product and the metal sheet or heat insulation board.

23. The method according to claim 22, wherein in step II), the adhesive layer is heated to a temperature of 85°C or higher, preferably 100°C or higher.

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