Ethylene / butene copolymer and adhesive composition comprising same

Abstract

The present invention relates to an ethylene / butene copolymer exhibiting excellent processability and adhesive properties, and to an adhesive composition comprising same.

Description

Ethylene / butene copolymer and adhesive composition containing the same

[0001] [Cross-reference with related applications]

[0002] This application claims the benefit of priority based on Korean patent application 10-2024-0195268 filed December 24, 2024, and all contents disclosed in the literature of said Korean patent applications are incorporated herein as part of this specification.

[0003]

[0004] [Technology Field]

[0005] The present invention relates to an ethylene / butene copolymer exhibiting excellent processability and adhesive properties, and an adhesive composition containing the same.

[0006]

[0007] Olefin polymerization catalyst systems can be classified into Ziegler-Natta and metallocene catalyst systems, and these two highly active catalyst systems have been developed according to their respective characteristics. Since its invention in the 1950s, the Ziegler-Natta catalyst has been widely applied in existing commercial processes. However, because it is a multi-site catalyst with multiple active sites, it is characterized by a wide molecular weight distribution of the polymer and has a problem in that there are limitations in securing desired properties due to the non-uniform compositional distribution of the comonomer.

[0008] Meanwhile, metallocene catalysts consist of a combination of a main catalyst, which is primarily composed of a transition metal compound, and a co-catalyst, which is an organometallic compound primarily composed of aluminum. Such catalysts are homogeneous complex catalysts and single-site catalysts; due to their single-site characteristics, they produce polymers with a narrow molecular weight distribution and a uniform compositional distribution of comonomers. Furthermore, they possess the ability to alter the stereoregularity, copolymerization characteristics, molecular weight, and degree of crystallinity of the polymer by modifying the catalyst's ligand structure and changing the polymerization conditions.

[0009] Meanwhile, linear low-density polyethylene is produced by copolymerizing ethylene and alpha-olefins at low pressure using a polymerization catalyst, and is a resin with a narrow molecular weight distribution, short chain branches of uniform length, and no long chain branches. In addition to the characteristics of general polyethylene, linear low-density polyethylene films have high breaking strength and elongation, as well as excellent tear strength and drop impact strength, so their use is increasing in stretch films and overlap films where it is difficult to apply conventional low-density polyethylene or high-density polyethylene.

[0010] However, when manufacturing linear low-density polyethylene using 1-butene or 1-hexene as a comonomer, productivity is higher compared to the process using 1-octene comonomer, but due to limitations in catalyst technology and process technology, the physical properties of these products are significantly inferior to those using 1-octene comonomer, and there is a problem of poor processability due to a narrow molecular weight distribution.

[0011] In addition, even if processability is improved, there is a problem in that the dispersion state according to molecular weight within the unit particles is not uniform, resulting in a rough extrusion appearance and unstable physical properties even under relatively good extrusion conditions.

[0012] Against this backdrop, there is a constant demand for the manufacture of superior products that strike a balance between physical properties and processability, and in particular, there is an increasing need for polyethylene copolymers with excellent processability.

[0013]

[0014] [Prior Art Literature]

[0015] [Patent Literature]

[0016] (Patent Document 1) U.S. Registered Patent No. 5,064,802

[0017]

[0018] The objective of the present invention is to provide an ethylene / butene copolymer that exhibits excellent processability and adhesive properties by controlling density, viscosity, and melt index, and an adhesive composition using the same.

[0019]

[0020] (1) The present invention provides an ethylene / butene copolymer that satisfies the following conditions (a) to (c).

[0021] (a) Density: 0.867 g / cc to 0.889 g / cc

[0022] (b) Viscosity: 4,500 cP to 16,000 cP at 177°C

[0023] (c) Melt index (190°C, 2.16 kg load condition): 500 dg / min to 1,600 dg / min

[0024] (2) The present invention provides an ethylene / butene copolymer according to (1), wherein the density is 0.868 g / cc to 0.888 g / cc.

[0025] (3) The present invention provides an ethylene / butene copolymer according to (1) or (2), wherein the viscosity is 4,600 cP to 15,900 cP at 177°C.

[0026] (4) The present invention provides an ethylene / butene copolymer in any one of (1) to (3), wherein the melt index (at 190°C, under 2.16 kg load conditions) is 520 dg / min to 1,580 dg / min.

[0027] (5) The present invention provides an ethylene / butene copolymer in which, in any one of (1) to (4), the number of vinyl functional groups per 1,000 carbons measured by nuclear magnetic spectroscopy is 0.01 to 2.0.

[0028] (6) The present invention provides an ethylene / butene copolymer in which, in any one of (1) to (5), the number of vinylidene functional groups per 1,000 carbons measured by nuclear magnetic spectroscopy is 0.01 to 0.9.

[0029] (7) The present invention provides an ethylene / butene copolymer in which, in any one of (1) to (6), the number of vinylene functional groups per 1,000 carbons measured by nuclear magnetic spectroscopy is 0.1 to 1.9.

[0030] (8) The present invention provides an ethylene / butene copolymer in which, in any one of (1) to (7), the number of trisubstituted vinyl functional groups per 1,000 carbons measured by nuclear magnetic spectroscopy is 0.01 to 0.8.

[0031] (9) The present invention provides an ethylene / butene copolymer in any one of (1) to (8), wherein the ethylene / butene copolymer has a melting temperature of 50°C to 90°C.

[0032] (10) The present invention provides an ethylene / butene copolymer in any one of (1) to (9), wherein the ethylene / butene copolymer has a crystallization temperature of 30°C to 70°C.

[0033] (11) The present invention provides an adhesive composition comprising an ethylene / butene copolymer according to any one of (1) to (10); and a tackifier.

[0034] (12) The present invention provides an adhesive composition in which, in (11) above, the adhesive agent is one or more selected from the group consisting of modified C5 hydrocarbon resin, styrene-modified terpene resin, fully or partially hydrogenated C9 hydrocarbon resin, hydrogenated cyclic aliphatic hydrocarbon resin and hydrogenated aromatic modified cyclic aliphatic hydrocarbon resin.

[0035] (13) The present invention provides an adhesive composition according to (11) or (12) wherein the adhesive composition has a viscosity of 350 cP to 1,250 cP at 177°C.

[0036]

[0037] The ethylene / butene copolymer of the present invention exhibits excellent processability and adhesive properties.

[0038]

[0039] Hereinafter, the present invention will be described in more detail to aid in understanding the invention.

[0040]

[0041] Terms and words used in the description and claims of the present invention shall not be interpreted as being limited to their ordinary or dictionary meanings, and shall be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0042]

[0043] Ethylene / butene copolymer

[0044] The ethylene / butene copolymer of the present invention satisfies the following conditions (a) to (c).

[0045] (a) Density: 0.867 g / cc to 0.889 g / cc

[0046] (b) Viscosity: 4,500 cP to 16,000 cP at 177°C

[0047] (c) Melt index (190°C, 2.16 kg load condition): 500 dg / min to 1,600 dg / min

[0048]

[0049] The inventors confirmed that by controlling the density, viscosity, and melt index of an ethylene / butene copolymer within a specific range, excellent processability and adhesive properties can be achieved during the manufacture of adhesives, and thus completed the present invention. In particular, by using butene as the alpha-olefin, the adhesive strength at low temperatures is superior compared to copolymers using other alpha-olefins such as ethylene / octene and ethylene / hexene, and the production cost of manufacturing the copolymer can be reduced.

[0050]

[0051] The ethylene / butene copolymer of the present invention has a density of 0.867 g / cc to 0.889 g / cc as measured according to ASTM D-792. The density may be 0.868 g / cc or higher, 0.869 g / cc or higher, or 0.870 g / cc or higher, and may be 0.888 g / cc or lower, 0.886 g / cc or lower, or 0.885 g / cc or lower, for example, 0.868 g / cc to 0.888 g / cc.

[0052] As the ethylene / butene copolymer has the above density, it exhibits excellent processability and excellent low-temperature adhesion.

[0053]

[0054] The ethylene / butene copolymer of the present invention has a viscosity of 4,500 cP to 16,000 cP at 177°C. Specifically, the viscosity may be 4,600 cP or more, 4,700 cP or more, 4,900 cP or more, or 5,000 cP or more, and may be 15,900 cP or less, 15,800 cP or less, 15,700 cP or less, 15,600 cP or less, 15,500 cP or less, or 15,400 cP or less, and for example, may be 4,600 cP to 15,900 cP at 177°C.

[0055] As the ethylene / butene copolymer has the above viscosity, it exhibits excellent processability and excellent adhesion at room temperature and low temperature.

[0056]

[0057] The ethylene / butene copolymer of the present invention has a melt index (at 190°C, under a 2.16 kg load condition) of 500 dg / min to 1,600 dg / min.

[0058] Specifically, the melt index may be 520 dg / min or more, 550 dg / min or more, or 570 dg / min or more, and may be 1,580 dg / min or less, 1,560 dg / min or less, or 1,550 dg / min or less, for example, 520 dg / min to 1,580 dg / min.

[0059] By having the above melt index, the ethylene / butene copolymer secures mechanical strength within the adhesive composition and simultaneously enables an appropriate working temperature when using the adhesive, and exhibits excellent adhesion at room temperature and low temperature.

[0060]

[0061] In the present invention, the melting temperature (Tm) of the ethylene / butene copolymer may be 50°C to 90°C. Specifically, it may be 51°C or higher, 53°C or higher, 55°C or higher, 88°C or lower, 85°C or lower, or 82°C or lower.

[0062] In the present invention, the crystallization temperature (Tc) of the ethylene / butene copolymer may be 30°C to 70°C. Specifically, it may be 32°C or higher, 34°C or higher, 36°C or higher, 68°C or lower, 65°C or lower, or 62°C or lower.

[0063] When the above melting temperature and crystallization temperature are met, low-temperature adhesion is excellent and processability is improved.

[0064] The melting temperature and crystallization temperature mentioned above can be measured using a Differential Scanning Calorimeter (DSC). Specifically, the copolymer is heated to 150°C and maintained for 5 minutes, then lowered to 20°C, and then the temperature is increased again. At this time, the rate of increase and decrease in temperature are each controlled to 10°C / min, and the result measured during the second temperature increase is used as the melting temperature, while the result measured during the temperature decrease is used as the crystallization temperature.

[0065]

[0066] In the present invention, the number of vinyl functional groups per 1,000 carbons measured by nuclear magnetic spectroscopy of the ethylene / butene copolymer may be 0.01 to 2.0. Specifically, it may be 0.02 or more, 0.03 or more, 0.04 or more, 1.8 or less, 1.5 or less, or 1.2 or less.

[0067] In addition, the ethylene / butene copolymer of the present invention may have 0.01 to 0.9 vinylidene functional groups per 1,000 carbon atoms. Specifically, it may be 0.02 or more, 0.8 or less, 0.7 or less, or 0.6 or less.

[0068] In addition, the ethylene / butene copolymer of the present invention may have 0.1 to 1.9 vinylene functional groups per 1,000 carbons as measured by nuclear magnetic spectroscopy. Specifically, it may be 0.11 or more, 0.12 or more, 1.8 or less, 1.7 or less, or 1.6 or less.

[0069] In addition, the ethylene / butene copolymer of the present invention may have 0.01 to 0.8 trisubstituted vinyl functional groups per 1,000 carbon atoms. Specifically, it may be 0.02 or more, 0.7 or less, 0.6 or less, or 0.5 or less.

[0070] The ethylene / butene copolymer according to the present invention has a number of tri-substituted vinyl functional groups as described above, thereby improving adhesion at low and room temperatures and excellent processability, while also exhibiting excellent long-term physical properties.

[0071] In addition, the ethylene / butene copolymer of the present invention may have a total number of unsaturated functional groups per 1,000 carbon atoms measured by nuclear magnetic spectroscopy of 0.2 to 5.5. More specifically, it may be 0.21 or more, 0.22 or more, 5.0 or less, 4.5 or less, or 4.0 or less.

[0072] The ethylene / butene copolymer according to the present invention has an unsaturated number of functional groups as described above, thereby improving adhesion at low and room temperatures and exhibiting excellent processability, while also showing excellent long-term physical properties.

[0073]

[0074] The vinyl group has the structure R-CH=CH2, the trisubstituted vinyl group has the structure RCH=CR'R", the vinylene has the structure RCH=CHR'(E-form) or Z-RCH=CHR'(Z-form), and the vinylidene has the structure RR'C=CH2. Here, R, R', and R" may each independently be a polymer chain or a branched chain of an alpha-olefin that is a comonomer.

[0075] In the present invention, the content of vinyl, vinylidene, vinylene, and trisubstituted vinyl in the copolymer can be calculated from the results of NMR analysis. Specifically, the copolymer can be dissolved in 1,1,2,2-tetrachloroethane D2 (TCE-d2) solvent and then measured using a Bruker AVANCE III 500 MHz NMR instrument at 393 K. 1The TCE-d2 peak in the H NMR spectrum is corrected to 6.0 ppm, and the content ratio of the comonomers is calculated using the integrated values ​​in the 1.4 ppm and 0.96 ppm regions. The content of each vinyl group, vinylidene group, vinylene group, and trisubstituted vinyl group observed at 4.7 ppm to 5.6 ppm is calculated (analytical method: AMT-3863). For peak assignment, refer to the literature [Macromolecules 2014, 47, 3282-3790].

[0076]

[0077] In addition, the ethylene / butene copolymer of the present invention may have a molecular weight distribution (MWD) of 1.5 to 3.5. Specifically, it may be 1.6 or more, 1.7 or more, or 1.8 or more, and 3.4 or less, 3.3 or less, or 3.2 or less.

[0078] According to one embodiment of the present invention, the ethylene / butene copolymer may have a weight-average molecular weight (Mw) of 16,000 g / mol to 29,000 g / mol. Specifically, it may be 17,000 g / mol or more, 18,000 g / mol or more, 19,000 g / mol or more, 28,000 g / mol or less, 27,000 g / mol or less, or 26,000 g / mol or less.

[0079] When the weight-average molecular weight satisfies the above range, a significant improvement in processability can be expected in conjunction with the viscosity of the adhesive composition containing it. That is, the mechanical properties, impact strength, and viscosity of the ethylene / butene copolymer can be controlled by adjusting the amount of catalyst used along with the type of catalyst used in the polymerization process, and in conjunction with the above conditions, improved processability can be exhibited while maintaining excellent mechanical properties.

[0080] Meanwhile, in the present invention, the weight-average molecular weight (Mw) and the number-average molecular weight (Mn) are polystyrene equivalent molecular weights analyzed by gel permeation chromatography (GPC), and the molecular weight distribution can be calculated from the ratio of Mw / Mn.

[0081]

[0082] In addition, in the above ethylene / butene copolymer, the content of butene, which is the comonomer, can be appropriately selected within a range that satisfies the above physical property requirements, specifically greater than 0 and less than or equal to 99 mol%, or 10 to 50 mol%.

[0083]

[0084] The ethylene / butene copolymer of the present invention can be produced by thermally decomposing a conventional ethylene / butene copolymer at an appropriate temperature and time. Any conventional ethylene / butene copolymer that can be easily obtained by a person skilled in the art, regardless of the route, such as a commercially available ethylene / butene copolymer or an ethylene / butene copolymer produced by a known method, may be used. More specifically, an ethylene / butene copolymer having a melt index (MI, under conditions of 190°C and a 2.16 kg load) of 5.0 g / 10 min to 15.0 g / 10 min and a density of 0.850 g / cc to 0.890 g / cc may be used, but is not limited thereto.

[0085] The above pyrolysis may specifically be heated at 350°C to 450°C, or at 360°C or higher, 370°C or higher, 380°C or higher, 390°C or higher, 440°C or lower, 430°C or lower, 420°C or lower, or 410°C or lower, for example, at 390°C to 410°C.

[0086] In addition, pyrolysis can be performed for 1 to 7 hours under the above temperature conditions, specifically for 1 hour or more, 6 hours or less, 5 hours or less, 4 hours or less, or 3 hours or less, more specifically for 1 to 3 hours, but is not limited thereto.

[0087]

[0088] In addition, the ethylene / butene copolymer of the present invention can be manufactured through a manufacturing method of polymerizing ethylene and butene while introducing hydrogen under a catalyst composition containing a metallocene compound.

[0089] The above hydrogen input amount may be 100 cc / min to 700 cc / min, 150 cc / min or more, 170 cc / min or more, 200 cc / min or more, 250 cc / min or more, 600 cc / min or less, 500 cc / min or less, 400 cc / min or less, or 350 cc / min or less, but is not limited thereto.

[0090]

[0091] Adhesive composition

[0092] The present invention provides an adhesive composition comprising the ethylene / butene copolymer and a tackifier.

[0093]

[0094] In the present invention, the adhesive composition may have a viscosity of 350 cP to 1,250 cP at 177°C. Specifically, the viscosity may be 360 ​​cP or more, 370 cP or more, 380 cP or more, 390 cP or more, or 400 cP or more, and may be 1,230 cP or less, 1,200 cP or less, 1,180 cP or less, 1,150 cP or less, or 1,120 cP or less.

[0095]

[0096] The above tackifier may be an aliphatic hydrocarbon resin, for example, a modified C5 hydrocarbon resin (C5 / C9 resin), a styrene-derived terpene resin, a fully or partially hydrogenated C9 hydrocarbon resin, a hydrogenated cyclic aliphatic hydrocarbon resin, a hydrogenated aromatic modified cyclic aliphatic hydrocarbon resin, and a mixture thereof.

[0097] The above tackifier is not particularly limited, but may be included in an amount of 5 to 70 parts by weight per 100 parts by weight of the adhesive composition, specifically in an amount of 20 to 70 parts by weight. If the tack resin is included in an amount less than 5 parts by weight, the viscosity of the adhesive composition may increase and processability may decrease, and if it is included in an amount exceeding 70 parts by weight, heat resistance may decrease.

[0098] The above ethylene / butene copolymer may be included in an amount of 10 to 50 parts by weight per 100 parts by weight of the adhesive composition, specifically in an amount of 15 to 30 parts by weight. Excellent adhesive properties can be maintained when the above numerical range is satisfied.

[0099]

[0100] In addition, the adhesive composition may further include a plasticizer. The plasticizer is not particularly limited, but may be, for example, a paraffinic or naphthenic plasticizing oil. Specifically, it may be a low molecular weight polymer such as an olefin oligomer, liquid polybutene, polyisoprene copolymer, liquid styrene-isoprene copolymer, or liquid hydrogenated styrene-conjugated diene copolymer, vegetable oil and derivatives thereof, or microcrystalline wax.

[0101] The above plasticizer is not particularly limited, but may be included in an amount of 10 to 50 parts by weight, specifically 20 to 40 parts by weight, relative to 100 parts by weight of the adhesive composition. If the above plasticizer is included in an amount less than 10 parts by weight, the adhesive strength of the adhesive composition may increase, which may reduce processability, and if it is included in an amount exceeding 50 parts by weight, the adhesive properties may decrease.

[0102]

[0103] In addition, the adhesive composition may further include an antioxidant to improve heat resistance and color.

[0104] At this time, the antioxidant is not particularly limited and may be used if it is commonly known in the art, and may be included in an amount of 0.01 to 5 parts by weight, or 0.01 to 1 part by weight, or 0.05 to 0.75 parts by weight per 100 parts by weight of the adhesive composition.

[0105] In addition, the adhesive composition may further include one or more additives selected from the group consisting of UV stabilizers, colorants or pigments, fillers, flow aids, coupling agents, crosslinking agents, surfactants, solvents, and combinations thereof.

[0106] The above filler may be selected from sand, talc, dolomite, calcium carbonate, clay, silica, mica, wollastonite, feldspar, aluminum silicate, alumina, hydrated alumina, glass beads, glass microspheres, ceramic microspheres, thermoplastic microspheres, barite, wood powder, or a combination thereof, and the filler may be present in an amount of 80 weight percent or less of the total composition.

[0107]

[0108] In the present invention, the adhesive composition may be a hot melt adhesive composition.

[0109] The present invention provides an article comprising a substrate coated with the adhesive composition. The article may be selected from, but is not limited to, tape, label, transfer paper, box, cardboard, tray, medical device, bandage, and sanitary product.

[0110]

[0111] Examples

[0112] The present invention will be explained in more detail below through examples. However, the following examples are intended to illustrate the present invention and do not limit the scope of the present invention.

[0113]

[0114] Example 1

[0115] 1 kg of ethylene / butene copolymer (LG Chem LUCENE LC675, MI: 14 g / 10 min, density: 0.877 g / cc) was weighed, placed in a 5 L batch reactor, and under vacuum to remove moisture and oxygen. Once removal was complete, the beaker was filled with argon (Ar) gas to inert it. A mechanical stirrer and impeller were connected to the beaker containing the ethylene / butene copolymer, and it was heated at 390°C for 2 hours while stirring at 100 rpm to pyrolyze it. After cooling the pyrolyzed copolymer sufficiently under argon (Ar), the beaker was opened to obtain the product.

[0116]

[0117] Example 2

[0118] 1 kg of ethylene / butene copolymer (LG Chem LUCENE LC675, MI: 14 g / 10 min, density: 0.877 g / cc) was weighed, placed in a 5 L batch reactor, and under vacuum to remove moisture and oxygen. Once removal was complete, the beaker was filled with argon (Ar) gas to inert it. A mechanical stirrer and impeller were connected to the beaker containing the ethylene / butene copolymer, and it was heated at 400°C for 2 hours while stirring at a speed of 100 rpm to pyrolyze it. After cooling the pyrolyzed copolymer sufficiently under argon (Ar), the beaker was opened to obtain the product.

[0119]

[0120] Example 3

[0121] 1 kg of ethylene / butene copolymer (LG Chem LUCENE LC675, MI: 14 g / 10 min, density: 0.877 g / cc) was weighed, placed in a 5 L batch reactor, and under vacuum to remove moisture and oxygen. Once removal was complete, the beaker was filled with argon (Ar) gas to inert it. A mechanical stirrer and impeller were connected to the beaker containing the ethylene / butene copolymer, and it was heated at 410°C for 3 hours while stirring at a speed of 200 rpm to pyrolyze it. After sufficiently cooling the pyrolyzed copolymer under argon (Ar), the beaker was opened to obtain the product.

[0122]

[0123] Example 4

[0124] A 1.5L continuous process reactor was preheated to 150°C while introducing 5.0 kg / h of hexane solvent and 0.8 kg / h of 1-butene. Triisobutylaluminum compound (0.045 mmol / min), metallocene catalyst (obtained according to KR 10-2236921 B1) (0.240 μmol / min), and dimethylanilinium tetrakis(pentafluorophenyl)borate co-catalyst (2.288 μmol / min) were simultaneously introduced into the reactor. Subsequently, ethylene (0.87 kg / h) and hydrogen gas (350 cc / min) were introduced into the reactor, and the copolymerization reaction was carried out by maintaining the reactor at 150.1°C for at least 60 minutes under a continuous process pressure of 89 bar to obtain an ethylene / butene copolymer. Afterward, the physical properties were measured after drying in a vacuum oven for at least 12 hours.

[0125]

[0126] Example 5

[0127] 1 kg of ethylene / butene copolymer (LG Chem LUCENE LF686, MI: 14 g / 10 min, density: 0.881 g / cc) was weighed, placed in a 5 L batch reactor, and under vacuum to remove moisture and oxygen. Once removal was complete, the beaker was filled with argon (Ar) gas to make it inert. A mechanical stirrer and impeller were connected to the beaker containing the ethylene / butene copolymer, and the copolymer was heated at 400°C for 1 hour while stirring at a speed of 100 rpm to perform pyrolysis. After cooling the pyrolyzed copolymer sufficiently under argon (Ar), the beaker was opened to obtain the product.

[0128]

[0129] Example 6

[0130] A 1.5L continuous process reactor was preheated to 140°C while introducing 5.0 kg / h of hexane solvent and 0.9 kg / h of 1-butene. Triisobutylaluminum compound (0.045 mmol / min), metallocene catalyst (obtained according to KR 10-2236921 B1) (0.180 μmol / min), and dimethylanilinium tetrakis(pentafluorophenyl)borate co-catalyst (1.716 μmol / min) were simultaneously introduced into the reactor. Subsequently, ethylene (0.87 kg / h) and hydrogen gas (250 cc / min) were introduced into the reactor, and the copolymerization reaction was carried out by maintaining the reactor at 140.1°C for at least 60 minutes under a continuous process pressure of 89 bar to obtain an ethylene / butene copolymer. Afterward, the physical properties were measured after drying in a vacuum oven for at least 12 hours.

[0131]

[0132] Comparative Example 1

[0133] 1 kg of ethylene / butene copolymer (LG Chem LUCENE LC675, MI: 14 g / 10 min, density: 0.877 g / cc) was weighed, placed in a 5 L batch reactor, and under vacuum to remove moisture and oxygen. Once removal was complete, the beaker was filled with argon (Ar) gas to inert it. A mechanical stirrer and impeller were connected to the beaker containing the ethylene / butene copolymer, and it was heated at 380°C for 3 hours while stirring at a speed of 100 rpm to pyrolyze it. After sufficiently cooling the pyrolyzed copolymer under argon (Ar), the beaker was opened to obtain the product.

[0134]

[0135] Comparative Example 2

[0136] 1 kg of ethylene / butene copolymer (LG Chem LUCENE LC675, MI: 14 g / 10 min, density: 0.877 g / cc) was weighed, placed in a 5 L batch reactor, and under vacuum to remove moisture and oxygen. Once removal was complete, the beaker was filled with argon (Ar) gas to inert it. A mechanical stirrer and impeller were connected to the beaker containing the ethylene / butene copolymer, and it was heated at 420°C for 2 hours while stirring at a speed of 200 rpm to pyrolyze it. After sufficiently cooling the pyrolyzed copolymer under argon (Ar), the beaker was opened to obtain the product.

[0137]

[0138] Comparative Example 3

[0139] A 1.5L continuous process reactor was preheated to 140°C while introducing 5.0 kg / h of hexane solvent and 0.6 kg / h of 1-butene. Triisobutylaluminum compound (0.045 mmol / min), metallocene catalyst (obtained according to KR 10-2236921 B1) (0.180 μmol / min), and dimethylanilinium tetrakis(pentafluorophenyl)borate co-catalyst (1.716 μmol / min) were simultaneously introduced into the reactor. Subsequently, ethylene (0.87 kg / h) and hydrogen gas (300 cc / min) were introduced into the reactor, and the copolymerization reaction was carried out by maintaining the reactor at 140.1°C for at least 60 minutes under a continuous process pressure of 89 bar to obtain an ethylene / butene copolymer. Afterward, the physical properties were measured after drying in a vacuum oven for at least 12 hours.

[0140]

[0141] Comparative Example 4

[0142] A 1.5L continuous process reactor was preheated to 140°C while introducing 5.0 kg / h of hexane solvent and 0.95 kg / h of 1-butene. Triisobutylaluminum compound (0.045 mmol / min), metallocene catalyst (obtained according to KR 10-2236921 B1) (0.180 μmol / min), and dimethylanilinium tetrakis(pentafluorophenyl)borate co-catalyst (1.716 μmol / min) were simultaneously introduced into the reactor. Subsequently, ethylene (0.87 kg / h) and hydrogen gas (200 cc / min) were introduced into the reactor, and the copolymerization reaction was carried out in a continuous process at 140.1°C for at least 60 minutes under a pressure of 89 bar to obtain an ethylene / butene copolymer. Afterward, the physical properties were measured after drying in a vacuum oven for at least 12 hours.

[0143]

[0144] Comparative Example 5

[0145] A 1.5L continuous process reactor was preheated to 140°C while introducing 5.0 kg / h of hexane solvent and 1.4 kg / h of 1-octene. Triisobutylaluminum compound (0.045 mmol / min), metallocene catalyst (obtained according to KR 10-2236921 B1) (0.180 μmol / min), and dimethylanilinium tetrakis(pentafluorophenyl)borate co-catalyst (1.716 μmol / min) were simultaneously introduced into the reactor. Subsequently, ethylene (0.87 kg / h) and hydrogen gas (250 cc / min) were introduced into the reactor, and the copolymerization reaction was carried out by maintaining the reactor at 140.1°C for at least 60 minutes under a continuous process pressure of 89 bar to obtain an ethylene / octene copolymer. Afterward, the physical properties were measured after drying in a vacuum oven for at least 12 hours.

[0146]

[0147] Comparative Example 6

[0148] A 1.5L continuous process reactor was preheated to 150°C while introducing 5.0 kg / h of hexane solvent and 1.4 kg / h of 1-octene. Triisobutylaluminum compound (0.045 mmol / min), metallocene catalyst (obtained according to KR 10-2236921 B1) (0.240 μmol / min), and dimethylanilinium tetrakis(pentafluorophenyl)borate co-catalyst (2.288 μmol / min) were simultaneously introduced into the reactor. Subsequently, ethylene (0.87 kg / h) and hydrogen gas (350 cc / min) were introduced into the reactor, and the copolymerization reaction was carried out in a continuous process at 150.1°C for at least 60 minutes under a pressure of 89 bar to obtain an ethylene / octene copolymer. Afterward, the physical properties were measured after drying in a vacuum oven for at least 12 hours.

[0149]

[0150] Experimental Example 1

[0151] The physical properties of each copolymer prepared in the above examples and comparative examples were compared and analyzed. The measurement conditions and methods are as follows.

[0152]

[0153] * Density

[0154] According to ASTM D-792, a sheet with a thickness of 3 mm and a radius of 2 cm was prepared using a 180°C press mold and cooled at 10°C / min and measured on a Mettler balance.

[0155]

[0156] * Viscosity (cP)

[0157] Measurements were taken using a Brookfield RVDV3T viscometer according to the following method. Specifically, a sample was placed in a 13 ml sample chamber and heated to 177°C using a Brookfield Thermosel. Once the sample was completely melted, the viscometer device was lowered and the spindle was fixed in the sample chamber. The rotation speed of the spindle (SC-29 high-temperature melting spindle) was fixed at 10 rpm, and readings were taken for at least 20 minutes or until the value stabilized, and the final value was recorded.

[0158]

[0159] * Melt Index (MI)

[0160] MI according to ASTM D-1238 2.16 (Condition E, 190℃, 2.16 kg load) was measured.

[0161]

[0162] * Molecular weight distribution

[0163] The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the produced copolymer were measured under the following gel permeation chromatography (GPC) analysis conditions.

[0164] - Column: Agilent Olexis

[0165] - Solvent: Trichlorobenzene (TCB)

[0166] - Flow rate: 1.0 ml / min

[0167] - Sample concentration: 1.0 mg / ml

[0168] - Injection volume: 200 µl

[0169] - Column temperature: 160℃

[0170] - Detector: Agilent High Temperature RI detector

[0171] - Standard: Polystyrene (corrected by a cubic function)

[0172] - Data processing: Cirrus

[0173] The molecular weight distribution was calculated from the ratio of Mw / Mn.

[0174]

[0175] * Melting temperature, crystallization temperature

[0176] The melting temperature (Tm) and crystallization temperature (Tc) can be obtained using a Differential Scanning Calorimeter (DSC 6000) manufactured by PerkinElmer. Specifically, using DSC, the temperature of the copolymer was increased to 200°C and maintained for 5 minutes under a nitrogen atmosphere, then cooled to 30°C, and the temperature was increased again while observing the DSC curve. At this time, the heating rate and cooling rate were each set to 10°C / min.

[0177] In the measured DSC curve, the melting temperature was determined as the maximum point of the endothermic peak during the second heating increase, and the crystallization temperature was determined as the maximum point of the exothermic peak during cooling.

[0178]

[0179] Referring to Table 1 above, it was confirmed that the ethylene / butene copolymers of Examples 1 to 6 according to the present invention have a density of 0.867 g / cc to 0.889 g / cc, a viscosity of 4,500 cP to 16,000 cP at 177°C, and a melt index (under conditions of 190°C, 2.16 kg load) of 500 dg / min to 1,600 dg / min. Meanwhile, the ethylene / butene copolymers of Comparative Examples 1 to 4 did not satisfy at least one of the density, viscosity, and melt index, and ethylene / octene copolymers were prepared in Comparative Examples 5 and 6.

[0180]

[0181] * Number of unsaturated functional groups

[0182] In addition, the number of each functional group of vinylene, trisubstituted vinyl, vinyl, and vinylidene per 1,000 carbon atoms in the copolymer was measured through nuclear magnetic spectroscopy analysis according to the following method.

[0183] The copolymer was dissolved in 1,1,2,2-tetrachloroethane D2 (TCE-d2) solvent and measured at 393K using a Bruker AVANCE III 500MHz NMR instrument.

[0184] 1 The TCE-d2 peak in the H NMR spectrum was corrected to 6.0 ppm, and the comonomer content ratio was calculated using the integrated values ​​in the 1.4 ppm and 0.96 ppm regions. The content of vinyl groups, vinylidene groups, vinylene groups, and trisubstituted vinyl groups observed at 4.7 ppm to 5.6 ppm was calculated (analytical method: AMT-3863). Peak assignment was referenced from the literature [Macromolecules 2014, 47, 3282-3790].

[0185]

[0186]

[0187] Experimental Example 2

[0188] 200g of the ethylene / alpha-olefin copolymer of the above-described examples and comparative examples, 200g of Eastman’s Regaltac H100W, 100g of Sasol’s H1, and 2.5g of an antioxidant were placed in a beaker, heated with a heating mantle to melt them, and then thoroughly stirred and mixed with an impeller to prepare an adhesive.

[0189]

[0190] * Viscosity measurement

[0191] Measurements were taken using a Brookfield RVDV3T viscometer according to the following method. Specifically, an 8 mL sample was placed in the sample chamber and heated to 150°C using a Brookfield Thermosel. Once the sample was completely melted, the viscometer device was lowered and the spindle was fixed in the sample chamber. The rotation speed of the spindle (SC-21 high-temperature melting spindle) was fixed at 5 rpm, and readings were taken for at least 20 minutes or until the value stabilized, and the final value was recorded.

[0192] The viscosity was measured using the same method when the heating temperature was set to 177℃.

[0193]

[0194] * Fiber Tear Measurement

[0195] The obtained adhesive was used to obtain a film of uniform thickness using a roll coater, transferred onto kraft paper, and adhered. The film was then stored in an oven at -30℃ and 25℃. After storage for a certain period, the film was peeled off, and the ratio of the adhered area was calculated to determine the fiber tear.

[0196] The evaluation was conducted according to the criteria below and is shown in Table 3.

[0197] ◎: Fiber Tear Exceeds 75%

[0198] ○: Fiber Tear Exceeds 50%

[0199] △: Fiber Tear Exceeds 25%

[0200] ×: Fiber Tear 25% or less

[0201]

[0202] * Set time measurement

[0203] After placing the adhesive in an oven at 180℃ and melting it sufficiently, it was applied to kraft paper to a uniform thickness. Kraft paper was then quickly attached over it. The time required for the bonded area to exceed 50% was measured while peeling off the kraft paper at 1-second intervals. A shorter set time indicates superior productivity, as it takes less time for the adhesive to solidify and acquire adhesive strength.

[0204] The evaluation was conducted according to the criteria below and is shown in Table 3.

[0205] ◎: Set time less than 5s

[0206] ○: Set time less than 10s

[0207] △: set time less than 15s

[0208] ×: set time 15s or more

[0209]

[0210] If the viscosity of the adhesive is excessively high, the room-temperature adhesive strength is improved, but the flowability is low, resulting in reduced processability; conversely, if the viscosity is excessively low, processability is good, but the adhesive strength is reduced, leading to a deterioration in performance as an adhesive. Meanwhile, if the density is low, the low-temperature adhesive strength is excellent, but the set time is long, resulting in reduced productivity; if the density is high, productivity is improved, but the low-temperature adhesive strength is reduced. In this regard, by using the ethylene / butene copolymer of the present invention, it is possible to manufacture an adhesive with optimal physical properties that can simultaneously exhibit excellent performance and processability. Meanwhile, in Comparative Examples 1 to 4 using an ethylene / butene copolymer that does not satisfy the density, viscosity, and melt index of the present invention, and Comparative Examples 5 and 6 using an ethylene / octene copolymer, it was confirmed that the physical properties of the adhesive were reduced compared to the examples.

Claims

1. An ethylene / butene copolymer satisfying the following conditions (a) to (c): (a) Density: 0.867 g / cc to 0.889 g / cc (b) Viscosity: 4,500 cP to 16,000 cP at 177°C (c) Melt index (190℃, 2.16 kg load condition): 500 dg / min to 1,600 dg / min.

2. In Claim 1, The above ethylene / butene copolymer having a density of 0.868 g / cc to 0.888 g / cc.

3. In Claim 1, The above viscosity is 4,600 cP to 15,900 cP of an ethylene / butene copolymer at 177°C.

4. In Claim 1, The above ethylene / butene copolymer has a melt index (under conditions of 190°C, 2.16 kg load) of 520 dg / min to 1,580 dg / min.

5. In Claim 1, The above ethylene / butene copolymer is an ethylene / butene copolymer having 0.01 to 2.0 vinyl functional groups per 1,000 carbons as measured by nuclear magnetic spectroscopy.

6. In Claim 1, The above ethylene / butene copolymer is an ethylene / butene copolymer having 0.01 to 0.9 vinylidene functional groups per 1,000 carbons as measured by nuclear magnetic spectroscopy.

7. In Claim 1, The above ethylene / butene copolymer is an ethylene / butene copolymer having 0.1 to 1.9 vinylene functional groups per 1,000 carbons as measured by nuclear magnetic spectroscopy.

8. In Claim 1, The above ethylene / butene copolymer is an ethylene / butene copolymer having 0.01 to 0.8 trisubstituted vinyl functional groups per 1,000 carbons as measured by nuclear magnetic spectroscopy.

9. In Claim 1, The above ethylene / butene copolymer is an ethylene / butene copolymer having a melting temperature of 50°C to 90°C.

10. In Claim 1, The above ethylene / butene copolymer is an ethylene / butene copolymer having a crystallization temperature of 30°C to 70°C.

11. An adhesive composition comprising an ethylene / butene copolymer according to any one of claims 1 to 10; and a tackifier.

12. In Claim 11, The adhesive composition wherein the above tackifier is one or more selected from the group consisting of modified C5 hydrocarbon resin, styrene-modified terpene resin, fully or partially hydrogenated C9 hydrocarbon resin, hydrogenated cyclic aliphatic hydrocarbon resin, and hydrogenated aromatic modified cyclic aliphatic hydrocarbon resin.

13. In Claim 11, The above adhesive composition is an adhesive composition having a viscosity of 350 cP to 1,250 cP at 177°C.

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