Contact Adhesives

Abstract

The invention relates to contact adhesive compounds containing 5 to 50 wt % copolymers of propylene having ethylene and/or having olefins, selected from the group of 1-olefins having 4 to 20 C atoms, wherein the copolymers have been produced with the aid of metallocene catalysts and are characterized by a) a flow point, measured in accordance with ASTM D97, of <50 C., b) a viscosity at 170 C. in the range from 20 to 3000 mPa.Math.s, measured with a rotary viscometer to DIN 53019, c) a density in the range from 0.84 to 0.90 g/cm.sup.3, measured at 23 C. in accordance with ISO 1183, d) a glass transition temperature of <35 C., measured in accordance with the DSC method according to DIN EN ISO 11357-2:2014.

Claims

1. A pressure-sensitive adhesive composition containing 5% to 50% by weight of copolymers of propylene with ethylene and/or with olefins selected from the group of the 1-olefins having 4 to 20 carbon atoms, where the copolymers have been prepared with the aid of metallocene catalysts and are characterized by a) a flow point, measured to ASTM D97, of <50 C., b) a viscosity at 170 C. in the range from 20 to 3000 mPa.Math.s, measured with a rotary viscometer to DIN 53019, c) a density in the range from 0.84 to 0.90 g/cm.sup.3, measured at 23 C. to ISO 1183, d) a glass transition temperature of <35 C., measured by the DSC method to DIN EN ISO 11357-2:2014.

2. The pressure-sensitive adhesive composition as claimed in claim 1, wherein the 1-olefin copolymers consist to an extent of 70-95% by weight of the propylene structural unit and to an extent of 5-30% by weight of structural units selected from ethylene and/or the group of the 1-olefins having 4 to 20 carbon atoms.

3. The pressure-sensitive adhesive composition as claimed in claim 1, wherein the 1-olefin copolymers consist to an extent of 70-95% by weight of the propylene structural unit and to an extent of 5-30% by weight of the ethylene structural unit.

4. The pressure-sensitive adhesive composition as claimed in claim 1, wherein the copolymers of propylene have polar modification.

5. The pressure-sensitive adhesive composition as claimed in claim 1, containing 50-95% by weight of one or more components selected from the group of the further polyolefins, the resins, the waxes, the plasticizers, the natural or synthetic rubbers, polyacrylates, polyesters, polychloroprenes, polyvinyl ethers or polyurethanes, the pigments, the fillers, the stabilizers and the antioxidants.

6. The use of pressure-sensitive adhesives as claimed in claim 1 for bonding of adherends.

Description

EXAMPLE 1

[0102] Preparation of a propylene ethylene copolymer of the invention (in accordance with EP 0384264A1, examples 1-16)

[0103] A dry 16 dm.sup.3 tank was purged with nitrogen and charged with 50 dm.sup.3 (STP) (corresponding to 3.1 bar) of hydrogen and with 10 dm.sup.3 of liquid propylene. Then 30 cm.sup.3 of toluenic methylaluminoxane solution (corresponding to 40 mmol of Al, average degree of oligomerization of the methylaluminoxane n=20) and 100 g of ethylene were added, and the mixture was stirred at 30 C. for 15 minutes.

[0104] In parallel, 8.0 mg of the metallocene dimethylsilyl-bis(1-indenylzirconium dichloride) were dissolved in 15 cm.sup.3 of toluenic methylaluminoxane solution (20 mmol of Al) and pre-activated by leaving it to stand for 15 minutes. The orange-red solution was introduced into the tank. The polymerization system was brought to 80 C. and kept at this temperature by appropriate cooling during the polymerization time (60 min). During the polymerization time, a further 330 g of ethylene were metered in homogeneously.

[0105] The resultant propylene-ethylene copolymer (yield 1.95 kg) had a propylene content of 79.5% by weight. The determination was made by .sup.13C NMR spectroscopy according to Ser van der Ven, Polypropylene and other Polyolefins, ch. 13, p. 568 ff., Amsterdam, Oxford, New York, Tokyo 1990. The copolymer showed the following indices:

[0106] Viscosity at 170 C.: 210 mPa.Math.s;

[0107] Density at 23 C.: 0.85 g/cm.sup.3;

[0108] Flow point: 21 C.;

[0109] Glass transition temperature: 48 C.

[0110] Performance Tests

[0111] Mixtures were produced according to tables 1 and 2. For this purpose, the stated components were stirred homogeneously with one another at about 170 C. in the molten state in the proportions by weight specified. The molten mass (about 150 g) was divided into two roughly equal portions on silicone-coated paper. One portion was introduced into the melt tank of a roll application machine of the Thermo 150 type (manufacturer: Hardo Maschinenbau GmbH) and discharged again after 5 minutes (preliminary flush of the machine). The second portion served to coat a glass plate (520 cm). The coat weight was determined by weighing. The glass plate was stored with the coated side downward on a silicone paper at room temperature for about 1 week. Then the coated side was bonded to a polyester film and compressed by pulling and pushing a contact roller over the bond 10 times with a load of 5 kg. Subsequently, the bonded test specimen was clamped into a peel tester (manufacturer: Zwick Roell), and the peel value was ascertained to DIN EN 1464, June 2010 (dry peel test).

TABLE-US-00001 TABLE 1 Application examples (inventive)/(use amounts in % by weight) AE 1 AE 2 AE 3 AE 4 AE 5 AE 6 AE 7 AE 8 AE 9 AE 10 AE 11 AE 12 Propylene-ethylene 30 30 30 30 30 30 30 30 30 30 30 30 copolymer according to ex. 1 Vestoplast 828 15 Vestoplast 888 15 Eastoflex 1060 15 Versify DE 4301.01 15 15 5 Licocene PP 1602 15 Vistamaxx 6102 10 Infuse 9807 15 Infuse 9817 15 Engage 8407 20 15 10 Sukorez SU 100 55 55 55 55 55 55 55 55 55 55 55 Dertophene T 55 Melt [mPa .Math. s] 3989 4265 1255 16570 610 14500 8200 937 43000 10500 3790 3200 viscosity (150 C.) Peel value [N/mm] 0.9 0.53 1.12 1.11 0.91 0.85 0.97 0.47 0.54 0.70 0.66 0.62 immediate

TABLE-US-00002 TABLE 2 Use examples (noninventive)/(use amounts in % by weight) AV 1 AV 2 AV 3 AV 4 Propylene-ethylene copolymer 55 70 according to example 1 Versify DE 4301.01 15 15 15 Engage 8407 15 Sukorez SU 100 55 55 30 15 Regalite 1010 20 20 Shell Catenex T145 10 10 Melt viscosity (150 C.) [mPa .Math. s] 4000 1500 7000 5000 Peel value immediate [N/mm] 0.20 0.34 0.21 0

[0112] Raw Materials Used:

[0113] Vestoplast and Eastoflex are amorphous poly--olefins (APAOs) from Evonik and Eastman respectively.

[0114] Versify, Infuse and Engage and Vistamaxx are ethylene copolymers from the manufacturers Dow and ExxonMobil respectively.

[0115] Licocene PP 1602 is a propylene-ethylene copolymer from the manufacturer Clariant.

[0116] Sukorez SU 100 and Regalite 1010 are hydrogenated hydrocarbon resins from the manufacturers Kolon Ind. and Eastman respectively; Dertophen T is a terpene-phenol resin from the manufacturer DRT.

[0117] Catenex T145 is a paraffin oil from Shell.