Composition for protecting shaped articles from corrosion

Abstract

The present invention relates to a composition for protecting an article from corrosion, in which the corrosion protection composition comprises: (i) an amorphous polymer composition comprising one or more polyisobutylene, each of which has a glass transition temperature of-40 DEG C or less as determined by differential scanning calorimetry (DSC); (ii) one or more butyl rubbers; (iii) one or more antioxidants; and (iv) one or more filler materials wherein the one or more polyisobutylene is independently selected from the group consisting of low molecular weight polyisobutylene (LMW PIB) having an average molecular weight Mv in the range of about 500 to about 20,000, and medium molecular weight polyisobutylene (MMW PIB) having an average molecular weight Mv in the range of about 20,000 to about 120,000.

Description

TECHNICAL FIELD

[0001] The present invention relates to a composition for protecting an article, such as a shaped article. In particular, the present invention relates to a composition for corrosion protection of an article. The article can be made of or consist essentially of one or more metals, metal compositions or alloys. The present invention relates in particular to a composition for isolating and sealing an article from contact with salt, moisture, water and other corrosive substances, thereby protecting the article from corrosion. The present invention also relates to a composition which can be used for protecting underground and underwater articles from corrosion. In the present invention, the article is envisaged to encompass oil lines, oil pipes, gas lines, gas pipes, manhole covers, underground storage tanks, manhole covers, welded joints, flanges, crane hooks, aluminium thermite welds in underground divisible shafts and T-joints. The present invention also relates to a composition which can be used for protecting materials used in onshore and offshore wind farms (wind turbines). BACKGROUND

[0002] In order to protect (shaped) articles from corrosion, a variety of materials are used. Shaped articles such as manhole covers, underground storage tanks, pipes or lines are often made of metals, metal compositions or alloys, which are susceptible to corrosion due to contact with salt, moisture, water and other corrosive components. Corrosion is obviously not welcome as it impairs the strength of the respective material and therefore has to be prevented or inhibited in order to prolong the service life of the shaped article as much as possible.

[0003] Materials for preventing corrosion, in particular long-term corrosion, have to have long-term chemical, physical, mechanical and thermal stability. Furthermore, as is well known in the art, the application of such materials is often a laborious, time-consuming and expensive process. In addition, these materials also have to have a good adhesion to the materials used, such as metals, metal compositions, alloys and other materials such as other coatings already present on the metal structure, such as epoxy coatings, plastics materials or polymers, such as polyethylene and polypropylene. Another requirement is that they have a very low permeability to water, salt and moisture.

[0004] Several materials are known in the art for inhibiting or preventing corrosion. Examples of such materials include bitumen and synthetic thermosetting resins, such as epoxy coatings and polyurethane coatings. A disadvantage of these materials is that a hard coating or sealing layer is created, which is easily cracked or torn under the influence of, for example, mechanical stress. Another disadvantage of these materials is that, for example, during application of these materials, the use of volatile solvents or other environmentally and humanly hazardous components is required. After application of these materials, for example, the solvents can evaporate, thereby forming a microporous sealing layer or coating, which is at least permeable to corrosive substances, such as salt, water and humidity.

[0005] Bitumen is also water permeable and generally does not meet the criteria set by the Dutch Inspection Institute for Water Supply Articles (KIWA). Furthermore, the glass transition temperature of bitumen generally exceeds about 10°C. As a result, under low temperature conditions, such as in winter, cracks easily occur.

[0006] Synthetic thermosetting resins are also easily cracked or torn by mechanical stress. Furthermore, they are not easily removed from the shaped article, which is important when the shaped article needs to be repaired or the degree of damage to the protection provided by the thermosetting resin needs to be repaired. Moreover, cleaning of the shaped article is also difficult, which is required when a new sealing or coating is to be applied, and therefore complex and laborious cleaning techniques (such as sandblasting) have to be used to sufficiently clean the shaped article. It will be apparent to the person skilled in the art that, if the shaped article is a natural gas or oil pipeline or pipe that is hundreds of miles long, replacing or repairing a sealing or coating made of synthetic thermosetting resin is a time-consuming and expensive operation. Finally, the application of a sealing or coating based on synthetic thermosetting resin is in itself difficult and laborious.

[0007] US 5,898,044 discloses a composition having improved properties compared to the above-mentioned materials. The composition comprises a non-polar, non-thermosetting fluid polymer, such as polyisobutylene, having a glass transition temperature of less than -20 °C and a surface tension of less than 40 mN / m at a temperature above its glass transition temperature, and a filler material. The composition can comprise an antioxidant, such as 2,6-di-tert-butyl-4-methylphenol (BHT). The composition can be used in conjunction with shrink sleeves, tapes, belts, mats or tapes having an open cell structure. However, the composition according to US 5,898,044 suffers from certain disadvantages. For example, if the composition contains 2,6-di-tert-butyl-4-methylphenol as antioxidant, the inventors found that the antioxidant leaches out of the composition, thereby reducing the protective properties of the composition due to oxidative degradation of the non-thermosetting fluid polymer. This has an adverse effect, for example, when the composition is applied to a shaped article, its adhesive strength and / or impermeability can decrease over time. As a result, the service life of the sealing system is reduced, requiring maintenance or replacement earlier than intended. Since sealing systems are required to have a long service life, typically 50 years or more, and their application is costly and laborious, it is clear to the skilled person that there is a need for improvement of such sealing systems. Therefore, the inventors have investigated this technical problem and found that the decrease in adhesive strength is caused by the leaching of 2,6-di-tert-butyl-4-methylphenol.

[0008] WO 99 / 56055 discloses a method for protecting a metal pipe from corrosion by applying a film to the metal pipe. The film comprises an outer layer, an intermediate layer and an inner layer. The outer layer is preferably made of a polymer, in particular high density polyethylene. The intermediate layer is preferably made of a metal, in particular aluminum. The inner layer preferably comprises an adhesive or mastic. The film has to be applied by heating. It is clear to the skilled person that this method is laborious and time-consuming, even less so than the method disclosed in US 5,898,044.

[0009] WO 99 / 48997 discloses a composition comprising one organic material susceptible to oxidative, thermal or light induced degradation and two or more antioxidants, wherein the organic material can be selected from a variety of materials including polyisobutylene. According to WO 99 / 48997, the composition can be used in a very wide range of applications, for example in lubricating oils, hydraulic oils and metal working fluids. However, WO 99 / 48997 does not disclose that the composition can be used for protecting a shaped article from corrosion.

[0010] EP A 1086963 discloses an ethylene copolymer composition useful as a gasket, for example, a corrosion resistant pipe joint. The patent discloses a stretch wrapping film having a multi-layer structure, for example, a multi-layer film having a non-stick surface and a tacky surface. Such multi-layer film has a film layer comprising an ethylene / alpha-olefin copolymer as an intermediate layer, a LLDPE non-stick layer having a density higher than the ethylene / alpha-olefin copolymer, and a tacky layer comprising a composition of an ethylene / alpha-olefin copolymer and 2% to 10% of a liquid polyisobutylene, a liquid polybutadiene, or the like. The stretch wrapping film has a thickness of 10-50 μm. SUMMARY

[0011] The present invention relates to an anti-corrosion composition comprising: (i) an amorphous polymer composition comprising one or more polyisobutylenes each having a glass transition temperature of -40°C or lower as determined by differential scanning calorimetry (DSC); (ii) one or more butyl rubbers; (iii) one or more antioxidants; and (iv) one or more filler materials, wherein the one or more polyisobutylenes are independently selected from a low molecular weight polyisobutylene (LMW PIB) having an average molecular weight Mv in the range of about 500 to about 20,000, and a medium molecular weight polyisobutylene (MMW PIB) having an average molecular weight Mv in the range of about 20,000 to about 120,000. DETAILED DESCRIPTION

[0012] The term "comprising", used in the specification and / or claims, including its variants, is used in its non-limiting sense to mean that items following the word are included, but not to the exclusion of items not specifically recited.

[0013] The term "consisting of", used in the specification and / or claims, including its variants, is used in its restrictive sense to mean that items following the word are included, but not items not specifically recited.

[0014] The term "consisting essentially of", used in the specification and / or claims, including its variants, is used in its restrictive sense to mean that items following the word are included, and items not specifically recited can be added, provided the added items do not materially alter the basic nature of the composition.

[0015] Use of the indefinite article "a" or "an" to refer to a certain element does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements. The indefinite article "a" or "an" generally indicates "at least one".

[0016] The present specification also encompasses all possible combinations of the individual embodiments, even if these combinations are not expressly disclosed. In other words, those skilled in the art will recognize that the embodiments can be combined, unless explicitly stated otherwise. This can result in combinations of components in the anticorrosion composition that are not expressly disclosed, which combinations are also within the scope of the present application.

[0017] The term "average molecular weight" as used herein can refer to "number average molecular weight (Mn)", "viscosity average molecular weight (Mv)", or "weight average molecular weight (Mw)", if the kind of average molecular weight is not specifically defined.

[0018] The term "polymer" includes homopolymers and copolymers.

[0019] The term "copolymer" includes polymers composed of two or more different monomers.

[0020] In general, the term "polyisobutylene" (PIB) is used in a broad sense by those skilled in the art to refer to amorphous polymers that contain isobutylene monomers as the main component and optionally contain other monomers, such as 1-butene, 2-butene and / or butadiene. These amorphous polymers have similar properties, especially in terms of glass transition temperature and surface tension. Depending on the desired purity of the polyisobutylene, they can be prepared by various methods (see Ullmanns "Encyklopadie der technischen Chemie", 4th edition, volume 19, pages 216-223, 1980, and volume 13, pages 621-623, 1977). The term "polyisobutylene" includes polymers containing isobutylene monomers and optionally monomers selected from C2-C 12 olefins, C4-C 12 dienes and mixtures thereof, the content of isobutylene monomers being, for example, at least about 50 wt.%, at least about 75 wt.%, at least about 90 wt.% or at least about 95 wt.%, and the content of the optionally present monomers being, for example, about 50 wt.% or less, about 25 wt.% or less, about 10 wt.% or less, about 5 wt.% or less, calculated on the total weight of the polyisobutylene.

[0021] The term "polyisobutylene homopolymer" is used herein to distinguish polyisobutylenes having a very high isobutylene monomer content from, for example, the above-described polyisobutylenes having a lower isobutylene monomer content as well as the polybutylenes and butyl rubbers described below. Thus, the term "polyisobutylene homopolymer" as used herein refers to a polymer consisting essentially of isobutylene monomers, i.e., a polymer comprising a weight content of isobutylene in excess of about 98% to about 100%, preferably about 99% to about 100%, more preferably about 99.5% to about 100%, even more preferably about 99.7% to about 100%, and in particular about 99.9% to about 100%, based on the total weight of the polymer. In a preferred embodiment of the present application, the polyisobutylene is a polyisobutylene homopolymer.

[0022] The term "polybutylene" as used herein refers to a polymer prepared from a C4 fraction obtained in a petroleum refinery process, e.g., a C4 fraction comprising 1-butene, 2-butene, isobutylene, and optionally butadiene.

[0023] "butyl rubber" refers to a polymer based on about 95 wt% to 98 wt% isobutylene and about 2 wt% to 5 wt% isoprene, based on the total weight of the polymer. This includes vulcanized butyl rubber and non-vulcanized butyl rubber. In addition, halogenated butyl rubbers are also included.

[0024] The terms "mechanical protection layer" and "outer wrap layer" are used interchangeably herein and both refer to a layer that mechanically protects one or more layers below from external influences.

[0025] Throughout the application, the terms "article" and "shaped article" are used interchangeably.

[0026] The corrosion protection composition of the present invention provides improved adhesion to various surfaces and has improved mechanical strength and improved mechanical load bearing capacity. Thus, the advantage of the present invention is that the composition of the present invention has improved solidification properties on the shaped article to be sealed or coated, including improved deformability and excellent adhesion, i.e. excellent adhesion to the surface of the shaped article. The composition of the present invention does not solidify, thus remains soft, and is water, moisture, salt tight, and has a tight porosity. The permeability can be adjusted, for example, by using and adding filler materials. The amount of filler material should not exceed a certain threshold, but should be below the critical value known to the skilled person. Another very important feature of the composition of the present invention is that if a coating or seal made from the composition of the present invention is subjected to a relatively small mechanical deformation, this damage will be automatically repaired in a relatively short time due to the fluid-like and / or visco-elastic properties of the composition of the present invention. That is, the composition has self-repairing properties, any deformation or damage will be repaired by the composition flowing into the holes or cavities caused by the mechanical deformation or soil stress. The self-repairing effect is especially obtained when the composition is wrapped around, for example, a tubular object and is completely covered by a flexible outer wrapping layer to which a tension is applied. The residual tension in the outer layer presses the composition towards the damaged site. Thus, the seal or coating comprising the composition of the present invention is not only smooth when applied, but even if indentations, imprints, dents, cavities, etc. are created due to mechanical forces, they will disappear over time and the smooth surface of the seal or coating will reappear. Obviously, due to this fluid-like property, any seal or coating comprising the composition of the present invention will not tear or break and will not develop internal stresses. Also, irregularities in the surface of the shaped article can be perfectly filled or wrapped by the composition of the present invention, whereas materials in the prior art often have problems in such cases.

[0027] According to the present invention, the composition of the present invention can be used in combination with a backing layer, forming a wrapping tape (to be defined in more detail below) for protecting an article against corrosion. Such a wrapping tape can be applied with a (outer) mechanical protection layer as defined above, thereby providing a complete coating according to the present invention. In addition to the above-mentioned properties, the composition of the present invention has improved resistance against dripping, i.e. in the T max+ No composition dripping was observed after 48 hours at 20°C (minimum temperature 80°C). This anti-dripping property was tested on a packaging tape, which means that the composite was extruded, calendered or rolled to a thickness of, for example, 2 mm, and the product also comprises a grid or mesh incorporated in the composite, and optionally a polymeric backing (e.g. PE) on one side of the product. The composition also exhibits good adhesion to steel and factory coatings (such as PE, PP, etc.) as measured by a peel test at a 10 mm / min peel rate, with a peel strength at 23°C of > 0.2 N / mm, and at T max (85°C) of > 0.02 N / mm (tested according to ISO 21809-3). For example, the peel strength of the inventive composition at 23°C is > about 0.3 N / mm, > about 0.4 N / mm, or > about 0.5 N / mm. In particular, the peel strength of the inventive composition at 23°C is > about 0.4 N / mm. Furthermore, in addition to the above, the peel strength of the inventive composition at 85°C is > about 0.03 N / mm, > about 0.04 N / mm, > about 0.05 N / mm, or > about 0.06 N / mm. The cohesive separation mode and the coverage of the substrate by the remaining composition is > 95%. Lap shear tests at a shear rate of 10 mm / min show that the lap shear strength at 23°C is > 0.004 N / mm 2 , and at T max > 0.002 N / mm 2 , and the cohesive separation mode and the coverage of the substrate by the remaining composition is > 95%. The specific electrical insulation resistance of the inventive composition is > 10E+08 Ohm-m 2 . We also observed that the impact resistance of the complete coating, including one layer of packaging tape and two layers of suitable overwrap, at 23°C is > 15 Joule, tested according to the ISO 21809-3 standard. Furthermore, the cathodic disbondment performance of the complete coating at 23°C and T max is 0 mm disbondment, no coating leakage was observed, and self-repairing has been completed.

[0028] In addition to the above, the inventive composition also exhibits tackiness (i.e. instant adhesion) and ease of use at different ambient temperatures. The ambient temperature depends on the location and can differ in the northern and southern hemispheres. The tackiness of the inventive composition is present at any ambient temperature.

[0029] Other advantages of the composition of the present invention are high chemical stability and resistance in a wide pH range, excellent electrochemical impedance, high cathodic protection performance, and substantially no cathodic disbondment. In addition, the composition can be used in an operating temperature range of -50 to 120°C, such as -50 to 100°C, -50 to 85°C, or -45 to 85°C. Any temperature, such as -40°C, -35°C, -30°C, -25°C, -20°C, -15°C, -10°C, -5°C, -0°C, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, or 110°C, can be combined with any of the above ranges.

[0030] The composition of the present invention has other advantages. Most protective systems require the use of a primer to provide adequate adhesion before being applied to a shaped article. The composition of the present invention does not require the use of a primer, which means that the composition can be applied in less time, thereby reducing the cost of application. Thus, in one preferred embodiment provided herein, the composition of the present invention does not require the use of a primer.

[0031] In desert-like environments, sandstorms often occur. Any protective system that must be applied by spray techniques cannot be used in such situations. However, the inventors have found that the composition of the present invention can be applied in such environments without resulting in a decrease in the quality of the protective layer.

[0032] Shaped articles can also be coated directly with the composition of the present invention under wet conditions, which is generally not possible with most systems in the prior art. Thus, in one embodiment, the corrosion-protective composition of the present invention can be applied to a wet or damp surface. In one embodiment, condensation should not occur when the composition of the present invention is applied.

[0033] Because the protective layer of the composition of the present invention is easily removed, shaped articles protected by the composition of the present invention are easily inspected and can be reapplied after inspection. Most materials in the prior art are much more difficult to remove. In addition, after removal of such prior art materials, the surface of the shaped article must be thoroughly cleaned before the material can be reapplied. This is not necessary with the present invention. Obviously, the protective layer of the composition of the present invention is also more easily tested. Amorphous polymer composition

[0034] The amorphous polymer composition of the present invention comprises one or more amorphous polymers. Amorphous polymers according to the present invention are polymers that do not have an ordered pattern in their molecular structure that would lead to a lack of crystallinity. According to the present invention, the amorphous polymer composition comprises one or more polyisobutylenes (PIB) having a glass transition temperature of -40°C or less as determined by differential scanning calorimetry (DSC). The amorphous polymer composition can also comprise one or more other amorphous polymers, preferably hydrocarbonaceous polymers. Preferably such hydrocarbon polymers are non-vulcanized (non-crosslinked) in nature such that their cold flow properties are optimized. In a preferred embodiment, the amorphous polymer composition comprises only one or more polyisobutylenes. The amorphous polymer composition of the present invention does not comprise any butyl rubber.

[0035] The amorphous polymer can comprise at least one low molecular weight polymer. The amorphous polymer can comprise at least one medium molecular weight polymer. Number average molecular weight and molecular weight distribution can be determined by gel permeation chromatography (GPC) as known in the art.

[0036] Average molecular weight can be expressed as number average molecular weight (Mn), viscosity average molecular weight (Mv), or weight average molecular weight (Mw). In one embodiment, the average molecular weight is viscosity average molecular weight (Mv).

[0037] The amorphous polymer has a glass transition temperature Tg of less than about -40°C, preferably less than about -50°C, more preferably less than about -60°C. According to general requirements, the amorphous polymer does not have a melting point or crystallization point when measured by differential scanning calorimetry (DSC) in the temperature range of -120 to +190°C. The amorphous polymer can have a surface tension at 20°C of less than about 50 mN / m, preferably less than about 40 mN / m. The glass transition temperature can be determined by DSC as known in the art, e.g. ISO 11357-2. The surface tension can be determined by methods known in the art (see S. Wu, J. Colloid. Interface. Sci., 31, 153, 1969; D. G. LeGrand, G. L. Gaines, Jr., J. Colloid. Interface. Sci., 31, 162, 1969).

[0038] According to the present invention, the polyisobutylene employed in the composition of the present invention has a glass transition temperature of less than -40°C, preferably less than -50°C, more preferably less than -60°C. At temperatures above the glass transition temperature of the polyisobutylene, the polyisobutylene can have a surface tension of less than 40 mN / m.

[0039] Surface tension parameters are also used to define certain types of polyisobutylenes. Generally, polymers with a relatively low surface tension have better flow, wetting, and adhesion properties than polymers with a relatively high surface tension. Furthermore, it is well known in the art that the surface tension increases with increasing molecular weight (also with increasing viscosity), although the increase in surface tension is generally negligible for molecular weights above 2000-3000, and the value approaches about 1 mN / m for an infinite molecular weight. See, for example, Polymer Handbook, 3rd edition, J. Bandrup and EH Immergut, page VI / 412 (1989). Thus, in the present application, surface tension is used to distinguish between very low molecular weight polyisobutylenes and the polyisobutylenes described herein, and thereby define a minimum value for the molecular weight. Thus, the polyisobutylenes according to the present application have a surface tension of less than 40 mN / m at a temperature above the glass transition temperature.

[0040] The one or more polyisobutylenes can comprise at least one low molecular weight polyisobutylene (LMW PIB). The low molecular weight polyisobutylene has an average molecular weight in the range of about 500 to about 20,000. The polyisobutylenes can also comprise at least one medium molecular weight polyisobutylene (MMW PIB). The medium molecular weight polyisobutylene has an average molecular weight in the range of about 20,000 to about 100,000. In one embodiment, the medium molecular weight polyisobutylene has an average molecular weight in the range of about 20,000 to about 120,000.

[0041] The polyisobutylenes according to the present application do not comprise any high molecular weight polyisobutylenes (HMW PIB), i.e. polyisobutylenes having an average molecular weight higher than 120,000. In one embodiment, the one or more polyisobutylenes according to the present application do not comprise any polyisobutylene having a viscosity average molecular weight Mv higher than 80,000.

[0042] The amorphous polymer composition comprises one or more polyisobutylenes independently selected from: a) a polyisobutylene having a number average molecular weight Mn of 500 to 5,000; b) a polyisobutylene having a viscosity average molecular weight Mv of 5,000 to 20,000; c) a polyisobutylene having a viscosity average molecular weight Mv of 20,000 to 35,000; d) a polyisobutylene having a viscosity average molecular weight Mv of 35,000 to 45,000; e) a polyisobutylene having a viscosity average molecular weight Mv of 45,000 to 55,000; f) a polyisobutylene having a viscosity average molecular weight Mv of 55,000 to 65,000; g) polyisobutylene having a viscosity average molecular weight Mv of 65,000 - 75,000; h) polyisobutylene having a viscosity average molecular weight Mv of 75,000 - 85,000; and i) polyisobutylene having a viscosity average molecular weight Mv of 85,000 - 120,000.

[0043] In one embodiment, the polyisobutylene (a) can have a viscosity average molecular weight Mv of 500 - 5,000. In any of the above disclosures, the average molecular weight can be number average molecular weight (Mn), viscosity average molecular weight (Mv), or weight average molecular weight (Mw). In one embodiment, the average molecular weight is viscosity average molecular weight (Mv) or can be defined as follows. In one embodiment, all of the above molecular weight ranges are number average molecular weight ranges (Mn). In one embodiment, all of the above molecular weight ranges are weight average molecular weight ranges (Mw). In one embodiment, all of the above molecular weight ranges are viscosity average molecular weight ranges (Mv). Polyisobutylenes having a viscosity average molecular weight, number average molecular weight, or weight average polymer weight in any one of ranges (a) to (i) above can be combined.

[0044] In one embodiment, the amorphous polymer composition can include only one of the polyisobutylenes described above. In another embodiment, the amorphous polymer composition can include two of the polyisobutylenes described above. In another embodiment, the amorphous polymer composition can include three of the polyisobutylenes described above. In another embodiment, the amorphous polymer composition can include four of the polyisobutylenes described above. In another embodiment, the amorphous polymer composition can include five of the polyisobutylenes described above. In another embodiment, the amorphous polymer composition can include six or more of the polyisobutylenes described above.

[0045] In one embodiment, the amorphous polymer composition comprises at least one LMW PIB, such as at least one polyisobutylene from group (a) and (b) above. In another embodiment, the amorphous polymer composition comprises at least one LMW PIB, such as at least one polyisobutylene from group (a) and (b) above, and at least one MMW PIB, such as at least one polyisobutylene from group (c) and (i) above. In another preferred embodiment, the amorphous polymer composition comprises only one LMW PIB from group (a) and (b) above, and only one MMW PIB from group (c) and (i) above. In a further embodiment, the amorphous polymer composition comprises at least one MMW PIB, such as at least one polyisobutylene from group (c) to (i) above. In a preferred embodiment, the amorphous polymer composition comprises only one MMW PIB, such as only one polyisobutylene selected from group (c) to (i) above; more preferably only one polyisobutylene selected from group (c) to (h) above. In a particularly preferred embodiment, the amorphous polymer composition comprises only one MMW PIB selected from group (c) to (g) above.

[0046] Without being bound by a particular theory, low molecular weight polyisobutylenes can provide tack, flow, and faster substrate wetting, while medium molecular weight polyisobutylenes can provide stronger adhesion and shear resistance. By using a mixture of polyisobutylenes of different molecular weights, the resulting compositions of the present application have not only improved properties in terms of tack, but also improved durability. Medium molecular weight grades of polyisobutylenes can serve as valuable elastomer bases; they have higher cohesive strength. Low molecular weight grades of polyisobutylenes are liquid-like, are suitable tackifiers, and can promote wetting and adhesion.

[0047] Mixtures of at least two polyisobutylenes of different molecular weights can harmonize competing factors, such as the ability of the adhesive to spread and wet the probe, and the composition's resistance to withdrawal.

[0048] In one embodiment, the one or more polyisobutylenes are used in an amount of about 10 to 70 weight percent. For example, the one or more polyisobutylenes can be used in an amount of about 15 to 65 weight percent, about 20 to 60 weight percent, about 25 to 55 weight percent, or about 30 to 50 weight percent. In a preferred embodiment, the one or more polyisobutylenes are used in an amount of about 30 to 50 weight percent. All based on the total weight of the corrosion protection composition. In a preferred embodiment, the one or more polyisobutylenes are used in an amount of about 40 to 60 weight percent, such as 40 to 55 weight percent. In a more preferred embodiment, only one polyisobutylene is used in an amount of about 40 to 60 weight percent, such as 40 to 55 weight percent.

[0049] In another embodiment, if two polyisobutylenes are used, the weight ratio is about 1 : 1, about 2: 1, about 3: 1, about 4: 1, or about 5: 1.

[0050] According to the present application, the amorphous polymer composition comprises from about 50 to about 100 weight percent of one or more polyisobutylenes, and from about 0 to about 50 weight percent of one or more other amorphous polymers, based on the total weight of the amorphous polymer composition. In a preferred embodiment, the amorphous polymer composition comprises from about 80 to about 100 weight percent of one or more polyisobutylenes, and from about 0 to about 20 weight percent of one or more other amorphous polymers, based on the total weight of the amorphous polymer composition. In a more preferred embodiment, the amorphous polymer composition comprises from about 90 to about 100 weight percent of one or more polyisobutylenes, and from about 0 to about 10 weight percent of one or more other amorphous polymers, based on the total weight of the amorphous polymer composition. In one embodiment, the amorphous polymer composition comprises more than 95 weight percent of one or more polyisobutylenes, such as more than 98 weight percent of one or more polyisobutylenes, more than 99 weight percent of one or more polyisobutylenes, or more than 99.5 weight percent of one or more polyisobutylenes, based on the total weight of the amorphous polymer composition. Most preferably, the amorphous polymer composition comprises about 100 weight percent of one or more polyisobutylenes. In yet another embodiment, the amorphous polymer composition comprises 100 weight percent of one or more polyisobutylenes. In yet another preferred embodiment, the amorphous polymer composition comprises 100 weight percent of one polyisobutylene. All of the above values are based on the total weight of the amorphous polymer composition.

[0051] The one or more other amorphous polymers are selected from suitable polymers such as, but not limited to, ethylene-propylene copolymers, ethylene-butene copolymers, ethylene-propylene-butene terpolymers, amorphous propylene copolymers, atactic polypropylene, poly(2-methyl-l-pentene), and mixtures thereof. According to a more preferred embodiment of the present application, the one or more other amorphous polymers are selected from polybutenes, atactic polypropylene, copolymers of propylene with C2-C12 olefins (and optionally dienes) other than propylene, copolymers of ethylene with C2-C12 olefins (and optionally dienes) other than ethylene, and mixtures thereof. According to a more preferred embodiment of the present application, the one or more other amorphous polymers are selected from ethylene-propylene copolymers, ethylene-butene copolymers, ethylene-propylene-butene terpolymers, ethylene-propylene-diene copolymers, polybutenes, atactic polypropylene, and mixtures thereof. In one embodiment, the amorphous polymer is selected only from the polyisobutylenes defined above.

[0052] The glass transition temperature of the one or more other amorphous polymers can be less than about -20°C, more preferably less than -40°C, most preferably less than -60°C. Further, it is preferred that the olefin polymer has a surface tension at 20°C of less than 40 mN / m. butyl rubber

[0053] The corrosion protection composition of the present application comprises one or more butyl rubbers. As described above, the term "butyl rubber" refers to a polymer based on about 95 wt% to about 98 wt% isobutylene and about 2 wt% to about 5 wt% isoprene, based on the total weight of the polymer. Both vulcanized and non-vulcanized butyl rubbers are contemplated. In a preferred embodiment, the butyl rubber is a non-vulcanized butyl rubber. The definition of butyl rubber as described in the present application also includes halogenated butyl rubbers. In one embodiment, halogenated butyl rubbers are not used.

[0054] In one embodiment of the present application, the corrosion protection composition comprises one butyl rubber. In another embodiment, the corrosion protection composition comprises a mixture of two butyl rubbers. In another embodiment, the corrosion protection composition comprises a mixture of three or more butyl rubbers. In a preferred embodiment, the corrosion protection composition comprises one butyl rubber.

[0055] The corrosion protection composition comprises about 5-25 wt% of one or more butyl rubbers. For example, the corrosion protection composition can comprise about 6-24 wt%, about 7-23 wt%, or about 8-20 wt% of one or more butyl rubbers, all amounts based on the total weight of the corrosion protection composition. In one embodiment, the amount of butyl rubber should not exceed 10 wt%. In another embodiment, the amount of one or more butyl rubbers is less than 10 wt% (but greater than 0 wt%). In another embodiment, one butyl rubber is used in an amount less than 10 wt% (but greater than 0 wt%). All amounts are based on the total amount of the corrosion protection composition.

[0056] The one or more butyl rubbers can have a Mooney viscosity (ML 1+8 at 125°C) in the range of about 25 MU to about 100 MU, for example, about 30 MU to about 75 MU, about 30 MU to about 50 MU, or about 30 MU to about 45 MU, measured according to ISO 289-1 or according to ASTM D1646. In one embodiment, the one or more butyl rubbers have a Mooney viscosity (ML 1+8 at 125°C) of < 55 MU according to ISO 289-1 or a Mooney viscosity (ML 1+8 at 125°C) of < 45 MU according to ASTM D1646. filler material

[0057] The composition of the present application comprises one or more (inert) fillers (i.e. filler materials).

[0058] In one embodiment, the filler comprises one or more inert inorganic fillers and / or one or more organic fillers. Examples of (inert) inorganic fillers are inorganic minerals, salts and / or oxides such as chalk, barium sulfate, calcium carbonate, calcium sulfate, calcium oxide, aluminum hydroxide, aluminum oxide, magnesium oxide, silicon dioxide, fumed silicon dioxide, titanium dioxide, quartz powder, glass, talc, slate and kaolin. In a preferred embodiment, the filler comprises calcium carbonate. In one embodiment, the filler comprises fumed silicon dioxide. In one embodiment, the filler comprises kaolin. In one embodiment, the filler comprises calcium carbonate and kaolin. In one embodiment, the filler comprises calcium carbonate and fumed silicon dioxide. In one embodiment, the filler comprises calcium carbonate, kaolin and fumed silicon dioxide. In a preferred embodiment, the filler is calcium carbonate.

[0059] In one embodiment, the corrosion protection composition of the present application further comprises one or more fillers in the form of pigments. The pigments can be selected from any pigment commonly used in the art. The corrosion protection composition can comprise 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt% or 0.5 wt% or more of the pigment, all amounts based on the total weight of the composition. In one embodiment, the corrosion protection composition comprises one pigment. In another embodiment, the corrosion protection composition comprises a mixture of two or more pigments.

[0060] In one embodiment, the filler comprises one or more organic fillers. Organic fillers can be, but are not limited to, cellulose, polystyrene, polyvinyl chloride, polyethylene, polypropylene, polyisoprene, polyamide and polyester or mixtures thereof. Polyethylene and polypropylene can be present in the amorphous polymer composition that makes up the corrosion protection composition. In one embodiment, the organic filler is a polymeric filler. When the polymer is used as a filler material, it is not necessary to meet the glass transition temperature or molecular weight requirements specified for the amorphous polymer composition. Syndiotactic polypropylene having a glass transition temperature higher than -20 °C can be used as a filler. In one embodiment, the corrosion protection composition does not comprise an organic filler.

[0061] The total amount of the one or more fillers in the corrosion protection composition is from 25 to 80 weight %, preferably from 30 to 75 weight %, more preferably from 35 to 70 weight %, more preferably from 40 to 70 weight %, more preferably from 40 to 60 weight %, most preferably from 40 to 55 weight %, all based on the total weight of the corrosion protection composition. In a more preferred embodiment, the one or more fillers are present in an amount of from about 30 to 60 weight %, for example more than 40 weight % but less than 60 weight %. In one embodiment, the total amount of fillers in the corrosion protection composition is at least 30 weight %, at least 40 weight %, at least 50 weight %, or at least 60 weight %, all based on the total weight of the corrosion protection composition. In one embodiment, the amount of fillers present is less than 60 weight % or less than 55 weight %.

[0062] According to the present application, all combinations of the above-mentioned fillers are encompassed. In one embodiment, the present application encompasses mixtures of two or more of any of the above-mentioned fillers in any of the above-mentioned amounts, for example three or more of any of the above-mentioned fillers, four or more of any of the above-mentioned fillers, five or more of any of the above-mentioned fillers, six or more of any of the above-mentioned fillers, or even more different fillers. In one embodiment, only one filler is used. In one embodiment, the corrosion protection composition of the present application does not contain any fibrous mineral filler material. Antioxidants

[0063] The properties of polymers, such as polyisobutylenes, can be strongly influenced by degradation reactions that can occur during production and use. In many cases, these degradation reactions are initiated by oxygen, which can be catalyzed by light, heat, water, and metal ions. Free radicals are formed in the initiation reaction, and unstable hydroperoxides are formed in chain transfer reactions. Hydroperoxides are the primary initiators of thermal and photo degradation processes. Antioxidants are often used to prevent such degradation reactions.

[0064] The antioxidants used in the present application can be one or more primary antioxidants and / or secondary antioxidants, one or more multifunctional antioxidants (i.e., antioxidants that function as both primary and secondary antioxidants) or lactones. According to the present application, primary antioxidants directly interfere with the propagation reactions that lead to degradation, i.e., terminate such chain transfer reactions, while secondary antioxidants induce the decomposition of hydroperoxides. The antioxidant can comprise a combination of two or more antioxidants. In one embodiment, the corrosion protection composition comprises two antioxidants. In one embodiment, the corrosion protection composition comprises three antioxidants. More preferably, the antioxidant is an antioxidant combination comprising at least two antioxidants, wherein preferably the antioxidant combination comprises a primary antioxidant and a secondary antioxidant. According to a preferred embodiment, the primary antioxidant is selected from sterically hindered phenolic compounds.

[0065] The one or more antioxidant(s) are present in an amount of up to 5% by weight. For example, the one or more antioxidant(s) are present in an amount of from about 0.01% to about 5% by weight, such as from about 0.05% to about 5% by weight, preferably from about 0.1% to about 4% by weight, more preferably from about 0.2% to about 3% by weight, most preferably from about 0.3% to about 2% by weight, all amounts based on the total weight of the corrosion protection composition of the present application. In one embodiment, the one or more antioxidant(s) are present in an amount of about 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1% by weight, based on the total weight of the composition of the present application. In one embodiment, the one or more antioxidant(s) are present in an amount of about 0.3% by weight. In another embodiment, the one or more antioxidant(s) are present in an amount of about 0.4% by weight. In another embodiment, the one or more antioxidant(s) are present in an amount of about 0.5% by weight.

[0066] According to the present application, the primary antioxidant can be selected from the group consisting of sterically hindered phenolic compounds, sterically hindered alkylthiomethylphenol or arylthiomethylphenol compounds, and secondary aromatic amines, but is not limited thereto.

[0067] In one embodiment, the sterically hindered phenolic compound is selected from the group consisting of compounds according to formula (I): wherein R1is C1-C4alkyl; n is 1, 2, 3 or 4; X is -CH2-, -CH2-CH2-C(O)-Y- or -CH2-C(O)-CH2-CH2-; Y is -O- or -NH-; and if n = 2, X is -CH2-CH2-C(O)-Y- wherein Y is bound to R2and R2is C2-C 12 alkylene, C4-C10alkyl interrupted by one or more oxygen atoms or sulfur atoms, C4-C10alkylene interrupted by one or more oxygen atoms or sulfur atoms, or a direct bond; and if n = 4, X is -CH2-CH2-C(O)-Y- wherein Y is bound to R2and R2is C4-C10alkyl interrupted by one or more oxygen atoms or sulfur atoms, C4-C10alkylene interrupted by one or more oxygen atoms or sulfur atoms, or a direct bond. 12 alkylene, C4-C10alkyl interrupted by one or more oxygen atoms or sulfur atoms, C4-C10alkylene interrupted by one or more oxygen atoms or sulfur atoms, or a direct bond; and if n = 4, X is -CH2-CH2-C(O)-Y- wherein Y is bound to R2and R2is C4-C10alkyl interrupted by one or more oxygen atoms or sulfur atoms, C4-C10alkylene interrupted by one or more oxygen atoms or sulfur atoms, or a direct bond. 10 alkyltetradyl.

[0068] C1-C4alkyl includes methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl and t-butyl. According to the present application, a preferred meaning of R1is t-butyl.

[0069] C2-C 12 C2-C10alkylene is preferably branched or straight. Examples of such groups are ethylene, propylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, decamethylene and dodecamethylene. R2is preferably C2-C10alkyl, more preferably C2-C6alkyl, even more preferably C2-C4alkyl, and most preferably C2-C3alkyl. 10Alkylene, more preferably C2-C8 alkylene, and especially C4-C8 alkylene, is typically hexamethylene.

[0070] C4-C interrupted by one or more oxygen or sulfur atoms 12 Alkylene is preferably C4-C 10 Alkylene, more preferably C4-C8 alkylene, especially C4-C6 alkylene. Suitable examples of groups are -CH2-O-CH2-CH2-O-CH2-, -CH2-(O-CH2-CH2)2-O-CH2-, -CH2-(O-CH2-CH2)3-O-CH2-, -CH2-(O-CH2-CH2-)4-O-CH2-, -CH2-CH2-O-CH2-CH2-O-CH2-CH2- and -CH2CH2-S-CH2-CH2-.

[0071] Particularly preferred C4-C atoms are spaced apart by one or more oxygen or sulfur atoms. 12 The alkylene groups are -CH2-CH2-O-CH2-CH2-O-CH2-CH2- and -CH2-CH2-S-CH2-CH2-.

[0072] According to the present invention, C4-C 10 -Alkyl tetrayl is preferably (-CH2)4C.

[0073] The preferred sterically hindered phenolic compound of this invention is one in formula (I) where n = 1 and R2 is C2-C. 20 Alkyl compounds. However, more preferred compounds are those in formula (I) where n = 2, R2 is a C2-C8 alkylene group, a C4-C8 alkylene group separated by sulfur or oxygen atoms, or, if Y is -NH-, R2 may also be a direct bond compound, and those in formula (I) where n = 4 and R2 is a C4-C8 alkyltetrayl group. Other preferred sterically hindered phenolic compounds of the present invention are those in formula (I) where R1 is tert-butyl, n = 1, 2 or 4, X is -CH2-CH2-C(O)-Y-, Y is an oxygen atom or -NH-, and if n = 1, R2 is a C4-C8 alkyltetrayl group. 14 -C 18 Alkyl compounds; if n=2, then R2 is a C4-C6 alkylene compound or a C4-C6 alkylene compound separated by oxygen atoms; if n=4, then R2 is a C4-C8 alkyltetramethyl compound.

[0074] Such sterically hindered phenolic compounds can be, for example, 2,6-di-tert-butyl-4-methylphenol, Irganox ® 1330, Irganox ® 1010, Irganox ® 1098, Irganox® 1076, Irganox ® 245, Irganox ® 259, Irganox ® 1035, Irganox ® 2246, Irganox ® 3114 and Irganox ® 3125, sterically hindered alkylthiomethylphenol Irganox ® 1520 (i.e. 2,4-dioctylthiomethyl-6-methylphenol) and aromatic based co-antioxidants comprising (polymeric) 1,2-dihydro-2,2,4-trimethylquinoline, such as Agerite ® MA.

[0075] Instead of or in addition to the sterically hindered phenol compound, a sterically hindered alkylthiomethylphenol or arylthiomethylphenol compound or a mixture of such compounds can be used. Such compounds are for example disclosed in US 4,358,616. A suitable and preferred example of a sterically hindered alkylthiomethylphenol or arylthiomethylphenol compound is Irganox 1520, i.e. 2,4-dioctylthiomethyl-6-methylphenol.

[0076] According to the present application, the co-antioxidant can be selected from the group consisting of phosphites and thioesters, but is not limited thereto. Suitable phosphites are for example disclosed in US 5,763,512. According to the present application, the phosphite is preferably selected from the group consisting of compounds of formula (II-IV): wherein R is a carbon atom, a nitrogen atom or an oxygen atom, and wherein n is 2, 3 or 4; wherein R5is a Ci-C4alkyl group, and X is a group as defined above for R2of formula (I) or a C6-Ci4hydrocarbyl group, wherein the hydrocarbyl group comprises one or more arylene groups. 18 hydrocarbyl group, wherein the hydrocarbyl group comprises one or more arylene groups.

[0077] According to the present application, the co-antioxidant is preferably selected from the group consisting of phosphites and thioesters. Suitable co-antioxidants are for example Irgafos ® 168, Irgafos ® 12 and Irgafos ® P-EPQ (both phosphites), and Lowinox ® TBM- 6, BNX ® DLTDP (CAS No. 123-28-4) and Morstille 18 DSTDP (both thioesters). The thioester is preferably selected from the group consisting of compounds of formula (VI): S-(R6-COOR7)2, wherein R6is a Ci-Ci4hydrocarbyl group, wherein the hydrocarbyl group comprises one or more arylene groups. 12alkyl, C6-C 12 alkyl, C6-C 12 aryl, C7-C 12 alkyl, C6-C 12 aryl, C7-C

[0078] In addition to the primary antioxidant and the secondary antioxidant, the antioxidant composition preferably comprises a further antioxidant selected from the group of lactones represented by formula (V): wherein R8-R 11 are independently hydrogen, halogen or C1-C 12 alkyl, and wherein R 12 -R 16 are independently hydrogen, halogen or C1-C 12 alkyl. Preferably, R8-R 11 and R 12 -R 16 are independently hydrogen or C1-C 12 alkyl. More preferably, R8and R 10 are C1-C6alkyl, R9and R 11 are hydrogen, and R 12 -R 16 are independently hydrogen or C1-C 12 alkyl. Even more preferably, R8and R 10 are C1-C6alkyl, R9and R 11 are hydrogen, R 14 and R 15 are C1-C6alkyl, and R 12 , R 13 and R 16 are hydrogen. Such lactones are for example disclosed in US 6,310,220.

[0079] The multifunctional antioxidant preferably comprises a primary antioxidant function and a secondary antioxidant function. Examples of multifunctional antioxidants include Irganox® L 115 and Irganox® 565.

[0080] An example of a lactone which can be used as antioxidant is Irganox® HP-136.

[0081] According to the present application, the composition preferably comprises a primary antioxidant, wherein the primary antioxidant is preferably selected from the group of sterically hindered phenolic compounds and secondary aromatic amines, most preferably from the group of sterically hindered phenolic compounds.

[0082] The composition can comprise a secondary antioxidant, wherein the secondary antioxidant is preferably selected from the group of phosphites.

[0083] In one embodiment, the composition comprises a combination of a primary antioxidant and a secondary antioxidant, preferably a combination of a primary antioxidant and a secondary antioxidant having a synergistic effect. Suitable combinations are combinations of Irganox and Irgafos antioxidants, for example Irganox® 1010 and Irgafos® 168.

[0084] In one embodiment, the composition comprises a combination of a primary antioxidant, a secondary antioxidant and a lactone. In one embodiment, the lactone is Irganox® HP - 136.

[0085] Other antioxidants that can be used in the present application are known in the art, for example described in “Additives for polyolefins”, Elsevier Sciences (2015), “Handbook of antioxidants”, Elsevier Science (2020), “Hand Book of Pressure Sensitive Adhesives and Coatings”, Notion Press (2018), “Stabilisers for Polyolefins”, Rapra Technology Limited (2001) and the like, the content of which is incorporated herein by reference. Exemplary corrosion protection composition

[0086] Any combination of polyisobutylenes, other amorphous polymers, butyl rubbers, antioxidants and fillers provided herein can be used in the corrosion protection composition. The sum of the weight percentages of all components provided herein is 100 wt.%. If additional components are present in the corrosion protection composition of the present application, the sum of the weight percentages of all components provided and the sum of the weight percentages of these additional components is 100 wt.%.

[0087] Any of the disclosure below can be combined with the general disclosure above. In other words, the present application encompasses any combination of the components described herein within the ranges described herein.

[0088] The corrosion protection composition of the present application can comprise (a) at least one LMW PIB, or (b) at least one MMW PIB and one or more butyl rubbers in a total amount of at most 10 wt.%, or (c) at least one MMW PIB and at most one butyl rubber, or (d) one MMW PIB and one butyl rubber, and / or (e) one or more butyl rubbers having a Mooney viscosity (1+8) at 125°C according to ISO 289 of < 55 MU.

[0089] The corrosion protection composition of the present application can comprise (a) at least one LMW PIB and one or more butyl rubbers, or (b) at least one MMW PIB and one or more butyl rubbers, or (c) at least one LMW PIB and at least one MMW PIB and one or more butyl rubbers, and (d) one or more butyl rubbers having a Mooney viscosity (1+8) at 125°C according to ISO 289 of < 55 MU.

[0090] In one embodiment of the present application, the corrosion protection composition consists of any combination of components provided herein. In other words, in the general description and embodiments provided herein, the term "comprising" can be replaced by the term "consisting of." Furthermore, in another embodiment, the term "comprising" can be replaced by the term "consisting essentially of."

[0091] An exemplary corrosion protection composition can comprise about 10 to 40 wt% of one or more LMW PIBs, about 5 to 20 wt% of one or more butyl rubbers, about 30 to 60 wt% of one or more fillers, and about 0.01 to 1 wt% of one or more antioxidants. The sum of all components is 100 wt%, all based on the total weight of the corrosion protection composition.

[0092] An exemplary corrosion protection composition can comprise about 10 to 40 wt% of one LMW PIB, about 5 to 20 wt% of one or more butyl rubbers, about 30 to 60 wt% of one or more fillers, and about 0.01 to 1 wt% of one or more antioxidants. The sum of all components is 100 wt%, all based on the total weight of the corrosion protection composition.

[0093] An exemplary corrosion protection composition can comprise about 10 to 40 wt% of one LMW PIB, about 5 to 20 wt% of one butyl rubber, about 30 to 60 wt% of one or more fillers, and about 0.01 to 1 wt% of one or more antioxidants. The sum of all components is 100 wt%, all based on the total weight of the corrosion protection composition.

[0094] An exemplary corrosion protection composition can comprise about 10 to 40 wt% of one LMW PIB, about 5 to 20 wt% of one butyl rubber, about 30 to 60 wt% of one filler, and about 0.01 to 1 wt% of one or more antioxidants. The sum of all components is 100 wt%, all based on the total weight of the corrosion protection composition.

[0095] Another exemplary corrosion protection composition can include about 10-40 wt% of one or more MMW PIBs, about 5-20 wt% of one or more butyl rubbers, about 30-60 wt% of one or more fillers, and about 0.01-1 wt% of one or more antioxidants. The sum of all components is 100 wt%, all based on the total weight of the corrosion protection composition.

[0096] Another exemplary corrosion protection composition can include about 10-40 wt% of one MMW PIB, about 5-20 wt% of one or more butyl rubbers, about 30-60 wt% of one or more fillers, and about 0.01-1 wt% of one or more antioxidants. The sum of all components is 100 wt%, all based on the total weight of the corrosion protection composition.

[0097] Another exemplary corrosion protection composition can include about 10-40 wt% of one MMW PIB, about 5-20 wt% of one butyl rubber, about 30-60 wt% of one or more fillers, and about 0.01-1 wt% of one or more antioxidants. The sum of all components is 100 wt%, all based on the total weight of the corrosion protection composition.

[0098] Another exemplary corrosion protection composition can include about 10-40 wt% of one MMW PIB, about 5-20 wt% of one butyl rubber, about 30-60 wt% of one filler, and about 0.01-1 wt% of one or more antioxidants. The sum of all components is 100 wt%, all based on the total weight of the corrosion protection composition.

[0099] Another exemplary corrosion protection composition can include about 40-50 wt% of one MMW PIB, about 5-10 wt% of one butyl rubber, about 30-60 wt% of one filler, and about 0.01-1 wt% of one or more antioxidants. The sum of all components is 100 wt%, all based on the total weight of the corrosion protection composition.

[0100] Another exemplary corrosion protection composition can include about 40-50 wt% of one MMW PIB, about 5-10 wt% of one butyl rubber, about 30-60 wt% of one filler, and about 0.01-1 wt% of one or more antioxidants. The sum of all components is 100 wt%, all based on the total weight of the corrosion protection composition.

[0101] A further exemplary corrosion protection composition can comprise about 10-40 wt.% of one or more LMW PIBs, about 10-40 wt.% of one or more MMW PIBs, about 5-20 wt.% of one or more butyl rubbers, about 30-60 wt.% of one or more fillers, and about 0.01-1 wt.% of one or more antioxidants. The sum of all components is 100 wt.%, all based on the total weight of the corrosion protection composition.

[0102] A further exemplary corrosion protection composition can comprise about 10-40 wt.% of one or more LMW PIBs, about 10-40 wt.% of one or more MMW PIBs, about 5-20 wt.% of one or more butyl rubbers, about 30-60 wt.% of one or more fillers, and about 0.01-1 wt.% of one or more antioxidants. The sum of all components is 100 wt.%, all based on the total weight of the corrosion protection composition. Packaging tape

[0103] The present application also relates to a tape for protecting an article against corrosion, wherein the tape comprises a layer comprising the corrosion protection composition according to the present application. Thus, the present application also solves the above-mentioned problems by providing a tape for protecting an article against corrosion. "Tape" and "packaging tape" are used interchangeably herein.

[0104] Provided herein is a (packaging) tape comprising a layer comprising a corrosion protection composition, said corrosion protection composition comprising: (i) an amorphous polymer composition comprising one or more polyisobutylenes, each having a glass transition temperature of -40 °C or lower as determined by differential scanning calorimetry (DSC); (ii) one or more butyl rubbers; (iii) one or more antioxidants; and (iv) one or more filler materials, wherein the amorphous polymer composition comprises one or more polyisobutylenes independently selected from low molecular weight polyisobutylenes (LMW PIBs) having an average molecular weight Mv in the range of about 500 to about 20,000, and medium molecular weight polyisobutylenes (MMW PIBs) having an average molecular weight Mv in the range of about 20,000 to about 120,000. The composition of the individual components is as detailed above.

[0105] Further, the tape comprises a first layer (a) comprising a backing (film, nonwoven, etc.) made of a polymer or copolymer as defined below, for example. The corrosion protection composition according to the present application is coated as a second layer (b) on one side of the first layer (a).

[0106] Due to the easy deformability of the second layer, the packaging tape according to the present application can be easily applied to the shaped article to be protected. Moreover, after application, the packaging tape can also be removed. Although the packaging tape can leave some residues on the surface of the shaped article due to cohesive breakage (cohesive breakage leaves 95% or more of the substrate surface covered with the composition according to the present application according to general industrial requirements and standards), these residues can be easily removed by scraping or any other suitable removal technique. Moreover, the packaging tape is particularly suitable for pipes, such as T-junctions, elbows, bends, flanges, etc. Moreover, the packaging tape according to the present application can be suitably used for repairing damaged or corroded shaped articles already equipped with some protective material according to the prior art, provided that the surface of the shaped article is cleaned to a minimum cleanliness grade St 2 according to ISO 8501-1.

[0107] If desired, the packaging tape can comprise a further layer (c) to protect the second layer (b). The protective layer (c) makes the tape easy to wind on a spool, reel or other suitable device during transport and prevents the layers of the tape from sticking to each other.

[0108] Layer (c) can be used as a release substrate, which can be removed from the tape when applying the tape. Layer (c) can comprise any material suitable for use as a release substrate, such as paper, siliconized PET, one or more C2-C20 olefin polymers or copolymers, polyvinyl chloride (PVC), polyurethane, etc. Moreover, this layer can also be used as a barrier layer to improve the ease of application and as a layer that allows proper adhesion to a subsequently applied mechanical protection layer. Due to the fluid and / or viscoelastic properties of the second layer (b), the use of a mechanical protection layer provides a self-repairing property.

[0109] Moreover, in one embodiment, the packaging tape preferably has a further layer (d) between layer (a) and layer (b), which comprises a reinforcing mesh layer having a woven, knitted or spool-knitted structure and which is deformable in two orthogonal directions. The reinforcing mesh layer can be made of polyolefin fibers, such as fibers made of ethane homopolymers or copolymers, propylene homopolymers or copolymers, polyesters, but is not limited thereto, these fibers being well known in the art.

[0110] The layer (a) of the packaging tape can comprise a polymer or copolymer. For example, the layer (a) can be made of one or more a-olefins and / or di-olefins, ethylene-tetrafluoroethylene (ETFE), nylon, polyurethane, etc. Further examples of such polymers and copolymers are EP(D)M elastomers, ethylene homopolymers, ethylene-a-olefin copolymers, propylene homopolymers and propylene-a-olefin copolymers. If the copolymer is an ethylene copolymer, which is the preferred embodiment of the present application, the a-olefin is preferably a C3-C12-a-olefin, in particular a C3-C8-a-olefin. Examples of suitable a-olefins are propylene, 1 -butene, 1 -hexene and 1 -octene. The ethylene copolymer preferably comprises 0.1 to 30 wt.%, in particular 0.1 to 20 wt.% of the a-olefin. The density of the ethylene homopolymer or copolymer (measured according to ASTM D 1248) is preferably 0.800 to 0.975 g / cm 3 , in particular 0.850-0.950 g / cm 3 . The melt index of the ethylene homopolymer or copolymer (measured according to ASTM D 1238) is preferably 0.1 to 50 g / min, in particular 0.2 to 20 g / min. The layer (a) of the packaging tape preferably comprises one or more of the following polymers: low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), ethylene propylene copolymer, ethylene propylene diene copolymer. According to a preferred embodiment of the present application, the layer (a) of the packaging tape comprises LDPE, MDPE, HDPE or LLDPE or a combination thereof, for example preferably a combination of LDPE and MDPE.

[0111] The layer (a) can comprise multiple layers, for example, it can be a multi-layer film comprising an outer layer of LLDPE and an inner layer of HDPE. Such multi-layer films are well known in the art. The layer (a) can also comprise different additives, for example pigments and fillers. In one embodiment, the layer (a) is only one layer.

[0112] The adhesive tape of the present application has a total thickness suitable for the intended use. For example, the total thickness of the adhesive tape is from about 1 to about 20 millimeters, more preferably from about 1 to about 15 millimeters, from about 1 to about 10 millimeters, from about 1 to about 7 millimeters, from about 1 to about 5 millimeters, or from about 1 to about 3 millimeters. In a preferred embodiment, the thickness is about 2 millimeters. The width of the adhesive tape can be adjusted as desired or appropriate, but is preferably from about 2.0 to about 100.0 centimeters, more preferably from about 2.5 to about 75.0 centimeters, even more preferably from about 3.0 to about 70.0 centimeters, even more preferably from about 4.0 to about 65.0 centimeters, and most preferably from about 5.0 to about 60.0 centimeters. The length of the adhesive tape can also be adjusted as desired or appropriate. For example, the adhesive tape can be several meters long and can be wound on a spool or reel prior to use. However, the adhesive tape can also be in a sheet form, and the length and width can be adjusted as desired or appropriate.

[0113] In one embodiment, the adhesive tape is applied to the article to be protected while the article to be protected is in a dry environment. The surface of the article to be protected typically does not require extensive pre-treatment. However, some pre-treatment can enhance the adhesive properties of the adhesive composition. For example, the article can comprise a pre-coated base layer, such as a pre-coat based on epoxy resin. In another embodiment of the present application, the article can have a polyolefin layer as a base layer. Thus, one application of the adhesive composition is in a process for manufacturing pre-coated steel pipes, wherein the pipes are provided with a pre-coat, preferably a polyolefin coating, preferably a polyethylene or polypropylene coating. In one embodiment, there is no base layer.

[0114] The present application also relates to a method for manufacturing a packaging tape for protecting a shaped article against corrosion, the packaging tape having a composition as provided herein. Furthermore, in the method for manufacturing a packaging tape for protecting an article against corrosion, the corrosion-protecting composition of the present application is laminated to a film as described above and preferably comprising a polymer or copolymer of one or more (substituted) a-olefins and / or diolefins (such as one or more C2-C20 a-olefins and / or diolefins), polyvinyl chloride (PVC), polyurethane or a polyester nonwoven, as defined above for layer (c) of the packaging tape of the present application.

[0115] After the lamination step, the surface of layer (b) not in contact with layer (a) is preferably protected by layer (c), wherein layer (c) can be any suitable material as described above.

[0116] If, as described above, layer (d) is present between layers (a) and (b), layer (a) and (d) are first laminated, and then layer (b) is applied to the surface of layer (d) opposite the surface in contact with layer (a). The thickness of layer (b) can be controlled by, for example, a knife.

[0117] After the packaging tape has been manufactured, it is preferably wound on a spool or reel.

[0118] Another important advantage of the packaging tape of the present invention is as follows. It is known in the art that sulfate-reducing bacteria often appear in defects in the protective layer of a formed article in the ground. These bacteria are capable of producing hydrogen sulfide, which is known to promote corrosion of metals (see, for example, S. Grobe et al., Materials and Corrosion, Vol. 47, pp. 413-424, 1996; M.J. Feijo et al., Materials and Corrosion, Vol. 651, pp. 691-697, 2000). Since infection and inclusions can occur during application of the protective layer, it is necessary to ensure that components that promote the growth of bacteria do not penetrate into the protective layer. Furthermore, it is believed that, in order to prevent the growth of such bacteria, at least one essential element (in particular, carbon, hydrogen, sulfur, and nitrogen) must be absent. Since the packaging tape of the present invention has low permeability to gases (air, i.e., nitrogen, oxygen, and water vapor) and is water-repellent, and does not contain nitrogen- and sulfur-containing compounds (unless a specific antioxidant containing nitrogen is used; but it is believed that this is not harmful, since only a small amount of antioxidant is added), the inventors believe that corrosion problems caused by these microorganisms do not occur with the packaging tape of the present invention.

[0119] Finally, it is worth noting that a protective system like butyl rubber (applied in a spiral to a formed article such as a pipeline) suffers from corrosion in the overlapping region between the different winding layers ("spiral corrosion"), because in the overlapping region the relatively hard butyl rubber winding layers do not come into close contact, resulting in air and water vapor being trapped. However, since layer (b) is fluid and / or viscoelastic, such problems do not occur with the packaging tape of the present invention.

[0120] The present invention also relates to a method for covering a formed article with a packaging tape, wherein the packaging tape comprises: (a) a first layer comprising a film comprising one or more polymers or copolymers of alpha-olefins and / or diolefins, and (b) a second layer comprising a composition comprising: (i) an amorphous polymer composition comprising one or more polyisobutylene blends, each of which has a glass transition temperature of -40°C or lower as determined by differential scanning calorimetry (DSC); (ii) one or more butyl rubbers; (iii) one or more antioxidants; and (iv) one or more filler materials, wherein the amorphous polymer composition comprises one or more polyisobutylenes selected from low molecular weight polyisobutylenes (LMW PIB) having an average molecular weight Mv in the range of from about 500 to about 20,000, and medium molecular weight polyisobutylenes (MMW PIB) having an average molecular weight Mv in the range of from about 20,000 to about 120,000.

[0121] According to the present application, the steel surface of the shaped article should be cleaned according to ISO 8501-1 standard to a minimum St 2 degree of cleanliness before the application of the packaging tape. St 2 degree is defined as "thorough hand and power tool cleaning" which can be achieved by techniques such as scraping, wire brushing, machine brushing and abrasion, which is further defined by ISO 8504-3. After the hand and power tool cleaning, the surface should be free of loose dirt and debris. The surface should be free of visible oil, grease and dirt, as well as poorly adhered mill scale, rust, paint coatings and foreign matter when viewed without magnification. The surface should have a faint metallic sheen and be free of anchor pattern. The surface of the shaped article can also be made of any of the polymers or copolymers described above.

[0122] The packaging tape is preferably wound on the shaped article such that subsequent layers of packaging tape overlap each other, wherein the width of the overlap is preferably at least 1.0 mm, more preferably at least 5.0 mm, and especially preferably at least 10.0 mm, depending on the thickness of the tape. Greater widths, such as about 50.0 mm, are also possible, but this is also dependent on the width of the packaging tape used, which will be apparent to the person skilled in the art. However, in order to achieve a proper seal, the width of the overlap must be at least 1.0 mm. Furthermore, the first and last turns are preferably wound substantially perpendicular to the direction of winding, that is to say, if the shaped article is, for example, a pipeline, the first and last turns are wound substantially in the circumferential direction and substantially perpendicular to the length direction of the pipeline. If the first strip of packaging tape has run out, a second strip of packaging tape can be applied at the end of the first strip, but the longitudinal overlap should be at least 1.0 mm, preferably at least 5.0 mm, and most preferably at least 10.0 mm. The packaging tape is preferably applied in a tension-free state.

[0123] In one embodiment of the present application, an outer packaging layer is wrapped around the shaped article, preferably after the application of the packaging tape. In one embodiment, the outer packaging layer is a polymeric tape or a heat shrinkable sleeve. Preferably, the outer packaging layer is made of a material comprising one or more polyolefins, preferably selected from the group consisting of ethylene homopolymers, ethylene copolymers, ethylene vinyl chloride copolymers, vinyl chloride polymers and ethylene vinyl acetate copolymers. According to a preferred embodiment of the present application, the outer packaging tape is a PVC film. The outer packaging tape is preferably applied under tension.

[0124] Preferably, the outer wrapping polymer tape is wrapped such that the width of overlap is at least 20% of the width of the outer wrapping polymer tape, preferably at least 40% of the width of the outer wrapping polymer tape.

[0125] The use of the composition according to the present application is particularly suitable for the field of corrosion protection. Thus, according to the present application, the article includes, but is not limited to: oil lines, oil pipes, gas lines, gas pipes, manhole covers, underground storage tanks, manhole covers, welded joints, flanges, crane hooks, aluminum thermite welds in underground divisible shafts, aluminum thermite welds in bridges, aluminum thermite welds in buildings, aluminum thermite welds in vehicles, and aluminum thermite welds in T-joints, etc. The article to be protected can also be any component of an onshore or offshore wind turbine or wind farm. Furthermore, it is preferred that the article is made mainly of metal, metal composition or metal alloy, most preferably of steel. The corrosion protection composition according to the present application can also be used for the protection of plastic materials, i.e. to prevent any form of degradation of the plastic (polymeric) material, or for the protection of concrete or concrete materials.

[0126] The composition according to the present application meets all the necessary industry requirements, such as the main standard of the oil and gas industry (ISO 21809-3:2016). Article to be protected

[0127] The present application also relates to an article comprising: (a) a layer of the corrosion protection composition as defined above on the surface of the article; and (b) a mechanical protection layer for protecting the layer of the corrosion protection composition.

[0128] The article can optionally comprise additional layers. In a preferred embodiment, the article further comprises a water protection layer. In another preferred embodiment, the mechanical protection layer (b) is itself water protective.

[0129] The mechanical protection layer (b) is applied on top of the corrosion protection layer (a) and covers the corrosion protection layer (a) completely. Suitable protection layers are provided, for example, by high shear tapes as known in the art. High shear tapes are disclosed, for example, in US 5,817,413 and US 6,033,776.

[0130] A layer of the corrosion protection composition of the present application can be comprised in a tape of the present application. The mechanical protection layer (b) can be applied to the article alone or, alternatively, the mechanical protection layer (b) can also be comprised in the tape. The present application also relates to an article comprising a tape of the present application. In said article, the surface of the article is covered by the tape.

[0131] In a preferred embodiment, the article is mainly made of metal, in particular steel. Alternatively, the surface of the article is mainly made of metal, in particular steel, while the interior of the article can comprise different materials. The article can for example be a tubular article, such as a natural gas or oil pipeline or line. The article can also be a column of an oil drilling or production rig or platform, a wind power tower, a support foundation or a bridge pier of a bridge, a support foundation or a concrete wall of a dam.

[0132] The present application will be further illustrated by the following examples, which however do not limit the scope of the present application in any way. Example Composition

[0133] Several compositions of the present application were prepared by mixing the components listed in Table 1 below (in wt%): Table 1 : Corrosion protection composition

[0134] The compositions were prepared as follows: first, a part of the components was mixed at about 160°C. After completion of the mixing process, a second part of the components was added and mixed again at 160°C. Finally, the remaining part of the components was added and mixed again at 160°C to obtain the final corrosion protection composition of the present application. Peeling test

[0135] Adhesion tests were performed on the packaging tapes comprising the backing and mesh described herein according to the peeling strength test method specified in ISO 21809-3:2016 Annex H. The requirements of ISO 21809-3:2016 Table 12 were used. The tensile testing machine was used to test and record the peel strength at a peel rate of 10 millimeters / minute, after which the test specimen was inspected for evidence of cohesive separation (expected performance), adhesive failure, and coverage of the substrate by the remaining film of the composition. The results are summarized in Table 2. Table 2: Adhesion

[0136] All tests showed a cohesive separation mode, no signs of adhesive failure were observed.

[0137] The results shown in Table 2 demonstrate that the corrosion protection compositions of the present application have a good adhesion.

Claims

1. An anticorrosion composition comprising: (i) an amorphous polymer composition comprising one or more polyisobutylenes, each having a glass transition temperature of -40 °C or lower as determined by differential scanning calorimetry (DSC); (ii) one or more butyl rubbers; (iii) one or more antioxidants; and (iv) one or more filler materials, wherein said one or more polyisobutylenes are independently selected from low molecular weight polyisobutylenes (LMW PIB) having an average molecular weight Mv in the range of from about 500 to about 20,000, and medium molecular weight polyisobutylenes (MMW PIB) having an average molecular weight Mv in the range of from about 20,000 to about 120,000.

2. The anticorrosion composition according to claim 1, wherein the anticorrosion composition comprises: • at least one LMW PIB, or • at least one MMW PIB and one or more butyl rubbers in a total amount of up to 10 wt.%, or • at least one MMW PIB and up to one butyl rubber, and / or • one or more butyl rubbers having a Mooney viscosity (1+8) at 125 °C according to ISO 289 of < 55 MU.

3. The anticorrosion composition according to any one of the preceding claims, wherein the one or more PIBs are selected from: a) polyisobutylenes having a number average molecular weight Mn of 500 - 5,000; b) polyisobutylenes having a viscosity average molecular weight Mv of 5,000 - 20,000; c) polyisobutylenes having a viscosity average molecular weight Mv of 20,000 - 35,000; d) polyisobutylenes having a viscosity average molecular weight Mv of 35,000 - 45,000; e) polyisobutylenes having a viscosity average molecular weight Mv of 45,000 - 55,000; f) polyisobutylenes having a viscosity average molecular weight Mv of 55,000 - 65,000; g) polyisobutylenes having a viscosity average molecular weight Mv of 65,000 - 75,000; h) polyisobutylenes having a viscosity average molecular weight Mv of 75,000 - 85,000; and i) polyisobutylenes having a viscosity average molecular weight Mv of 85,000 - 120,000.

4. The anticorrosion composition according to any one of the preceding claims, wherein the one or more PIBs are present in an amount of 10 - 70 wt.% based on the total weight of the anticorrosion composition.

5. The anticorrosion composition according to any one of the preceding claims, wherein the one or more butyl rubbers are present in an amount of 5 - 25 wt.% based on the total weight of the anticorrosion composition.

6. The corrosion protection composition according to any one of the preceding claims, wherein the one or more antioxidants comprise one or more primary antioxidants and one or more secondary antioxidants, the one or more primary antioxidants comprising a sterically hindered phenol compound, a sterically hindered alkylthiomethylphenol or arylthiomethylphenol compound and a secondary aromatic amine, with the proviso that the sterically hindered phenol compound is not 2,6-di-tert-butyl-4-methylphenol, and wherein the antioxidants are present in an amount of up to 5 wt.%, based on the total weight of the corrosion protection composition.

7. The corrosion protection composition according to claim 6, wherein the sterically hindered phenol compound comprises at least two sterically hindered phenol groups, and / or wherein the secondary antioxidant is selected from the group consisting of phosphites and thioesters.

8. The corrosion protection composition according to claim 6 or 7, wherein the antioxidant composition further comprises a lactone.

9. The corrosion protection composition according to any one of the preceding claims, wherein the content of one or more filler materials is in the range of 25 to 70 wt.%, based on the total weight of the corrosion protection composition.

10. A packaging tape for protecting an article, comprising (a) a first layer, and (b) a second layer comprising the corrosion protection composition according to any one of claims 1 to 8.

11. The packaging tape according to claim 10, wherein the first layer is a film comprising one or more polymers or copolymers of alpha-olefins and / or diolefins.

12. Use of a composition for protecting an article against corrosion, comprising: (a) applying a layer of the corrosion protection composition according to any one of claims 1 to 9 or the packaging tape according to claim 10 or 11; and, optionally, (b) applying a mechanical protection layer on top of the layer of the corrosion protection composition or the packaging tape.

13. A method of manufacturing a packaging tape, wherein a corrosion protection composition is laminated to a film, the film comprising a polymer or copolymer, and the corrosion protection composition comprises: (i) an amorphous polymer composition comprising one or more polyisobutylenes, each having a glass transition temperature of -40 °C or lower as determined by differential scanning calorimetry (DSC); (ii) one or more butyl rubbers; (iii) one or more antioxidants; and (iv) one or more filler materials, wherein the one or more polyisobutylenes being independently selected from low molecular weight polyisobutylenes (LMW PIB) having an average molecular weight Mv in the range of about 500 to about 20,000, and medium molecular weight polyisobutylenes (MMW PIB) having an average molecular weight Mv in the range of about 20,000 to about 120,000.

14. A method of covering a shaped article with a packaging tape according to claim 10 or 11.

15. The method of covering a molded article with packaging tape according to claim 14, wherein, The packaging tape is wrapped around the shaped article such that subsequent layers of the packaging tape overlap each other.

16. The method according to claim 14 or 15, wherein after applying the packaging tape, a mechanical protection layer is wrapped around the shaped article.

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