Multi-layer product

Abstract

Multilayer product comprising at least one layer of an acrylate-based foam carrier (S); and a multiphase polymer composition (P) applied to this layer; the multiphase polymer composition (P) comprising: a comb copolymer (A) which is obtainable by polymerization of at least one (meth)acrylate monomer in the presence of at least one macromer selected from the group consisting of polymerizable ethylene-butylene, ethylene-propylene, ethylene-butylene-propylene and isobutylene macromers, and which forms a continuous acrylate phase and a discontinuous hydrocarbon phase Kw; and at least one hydrocarbon component (B) which is soluble in the hydrocarbon phase Kw of the comb copolymer (A) and comprises at least one plasticizer resin and at least one solid resin;
the multiphase polymer composition (P) having a continuous acrylate phase with a static glass transition temperature Tg(Ac), measured by the DSC method, and a discontinuous hydrocarbon phase Kw1, comprising the hydrocarbon component (B) and having a static glass transition temperature Tg(Kw1), measured by the DSC method, where Tg(Kw1) is higher than Tg(Ac) by 35 to 60 kelvins.

Claims

1. Multilayer product comprising at least one layer of an acrylate-based foam carrier (S); and a multiphase polymer composition (P) applied to this layer; the multiphase polymer composition (P) comprising: a comb copolymer (A) obtained by polymerization of at least one (meth)acrylate monomer in the presence of at least one macromer selected from the group consisting of polymerizable ethylene-butylene, ethylene-propylene, ethylene-butylene-propylene and isobutylene macromers, and which forms a continuous acrylate phase and a discontinuous hydrocarbon phase Kw; a hydrocarbon component (B) which is soluble in the hydrocarbon phase Kw of the comb copolymer (A) and comprises at least one plasticizer resin and at least one solid resin; the multiphase polymer composition (P) having a continuous acrylate phase with a static glass transition temperature Tg(Ac), measured by the DSC method, and a discontinuous hydrocarbon phase Kw1, comprising the hydrocarbon component (B) and having a static glass transition temperature Tg(Kw1), measured by the DSC method, where Tg(Kw1) is higher than Tg(Ac) by 35 to 60 kelvins.

2. Multilayer product according to claim 1, wherein the acrylate-based foam carrier (S) is a viscoelastic foam carrier.

3. Multilayer product according to claim 1, wherein, the acrylate forming the layer of the foam carrier (S) is a polyacrylate obtained by free or controlled radical polymerization of one or more acrylates and alkyl acrylates.

4. Multilayer product according to claim 1, wherein, the acrylate forming the layer of the foam carrier (S) is a crosslinked polyacrylate.

5. Multilayer product according to claim 1, wherein, the acrylate forming the layer of the foam carrier (S) is a polyacrylate obtained by polymerization of monomers consisting of monomers of the following groups (a1) to (a3): (a1) 70 to 100 wt % of acrylic esters and/or methacrylic esters and/or a free acid as per structural formula (I): ##STR00004## where R.sup.1 is H or CH.sub.3 and R.sup.2 represents H or C.sub.1-C.sub.14 alkyl; (a2) 0 to 30 wt % of olefinically unsaturated monomers which are copolymerizable with the monomers of group (a1) and have at least one functional group; and (a3) optionally further acrylates and/or methacrylates and/or olefinically unsaturated monomers, which are copolymerizable with the monomers of group (a1) and have at least one functional group which leads by means of a coupling reagent to covalent crosslinking.

6. Multilayer product according to claim 5, wherein the monomers of group (a1) are selected from the group consisting of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, n-butyl acrylate, n-butyl methacrylate, n-pentyl acrylate, n-hexyl acrylate, n-hexyl methacrylate, n-heptyl acrylate, n-octyl acrylate, n-nonyl acrylate, lauryl acrylate, stearyl acrylate, stearyl methacrylate, behenyl acrylate and their branched isomers and mixtures thereof; and/or the monomers of group (a2) are selected from the group consisting of maleic anhydride, itaconic anhydride, glycidyl methacrylate, benzyl acrylate, benzyl methacrylate, phenyl acrylate, phenyl methacrylate, tert-butylphenyl acrylate, tert-butylphenyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, 2-butoxyethyl methacrylate, 2-butoxyethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, diethylaminoethyl methacrylate, diethylaminoethyl acrylate, tetrahydrofurfuryl acrylate, and mixtures thereof; and/or the monomers of group (a3) are selected from the group consisting of hydroxyethyl acrylate, 3-hydroxypropyl acrylate, hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, allyl alcohol, itaconic acid, acrylamide and cyanoethyl methacrylate, cyanoethyl acrylate, 6-hydroxyhexyl methacrylate, N-tert-butylacrylamide, N-methylolmethacrylamide, N-(butoxymethyl)methacrylamide, N-methylolacrylamide, N-(ethoxymethyl)acrylamide, N-isopropylacrylamide, vinylacetic acid, -acryloyloxypropionic acid, trichloroacrylic acid, fumaric acid, crotonic acid, aconitic acid, dimethylacrylic acid, 4-vinylbenzoic acid, and mixtures thereof.

7. Multilayer product according to claim 1, wherein, the multilayer product is an adhesive tape; and/or the layer of the foam carrier (S) is foamed through use of microballoons.

8. Multilayer product according to claim 1, wherein, the static glass transition temperature of the discontinuous hydrocarbon phase within the polymer composition (P), Tg(Kw1), is in a range from 5 to +15 C., and/or the static glass transition temperature of the continuous acrylate phase within the polymer composition (P), Tg(Ac), is below 10 C.

9. Multilayer product according to claim 1, wherein, the fraction of the comb copolymer (A) makes up 30-64 weight percent, based on the total weight of the comb copolymer (A) and of the at least one hydrocarbon component (B) within the polymer composition (P); and/or the macromer units within the comb copolymer (A) make up 5-25 weight percent, based on the total weight of the comb copolymer (A).

10. Multilayer product according to claim 1, wherein, the at least one (meth)acrylate monomer which can be used for preparing the comb copolymer (A) comprises at least one monomer selected from the group consisting of acrylic acid, methacrylic acid, 2-ethylhexyl acrylate, methyl acrylate, butyl acrylate, isobornyl acrylate, stearyl acrylate, isostearyl acrylate, amyl acrylate, isooctyl acrylate, decyl acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate and 4-hydroxybutyl acrylate, preferably from the group consisting of acrylic acid, methacrylic acid, 2-ethylhexyl acrylate, methyl acrylate, butyl acrylate, isobornyl acrylate, stearyl acrylate, isostearyl acrylate, amyl acrylate, isooctyl acrylate and decyl acrylate.

11. Multilayer product according to claim 1, wherein, the polymerization of the at least one (meth)acrylate monomer which can be used for preparing the comb copolymer (A) is carried out in the presence of at least one further copolymerizable monomer, this at least one further copolymerizable monomer being selected from the group consisting of itaconic acid, itaconic anhydride, maleic acid, maleic anhydride, vinyl acetate, vinyl butyrate, vinyl propionate, vinyl isobutyrate, vinyl valerate, vinyl versatates, N-vinylpyrrolidone and N-vinylcaprolactam.

12. Multilayer product according to claim 1, wherein, the plasticizer resin and the solid resin of the hydrocarbon component (B) have a number-average molecular weight Mn of 1000 g/mol or less, measured by the GPC method.

13. Multilayer product according to claim 12, wherein the polymer composition (P) further comprises a further hydrocarbon compound (C), whose number-average molecular weight Mn, measured by the GPC method, is more than 1000 g/mol, and the polymer composition optionally has a static glass transition temperature Tg(C) which lies between the glass transition temperatures of the continuous acrylate phase, Tg(Ac), and of the discontinuous hydrocarbon phase, Tg(Kw1).

14. Multilayer product according to claim 1, wherein, the polymer composition (P) is a pressure-sensitive adhesive; and/or the multiphase polymer composition (P) applied to the layer of the foam carrier (S) is applied in the form of a layer having a weight per unit area of 40 to 100 g/m.sup.2.

15. Method for producing a multilayer product according to claim 1, comprising the steps of: (i) providing a layer of an acrylate-based foam carrier (S) having a top side and a bottom side; and (ii) applying a multiphase polymer composition (P) to the top side and/or bottom side of the foam carrier (S), the multiphase polymer composition (P) comprising: a comb copolymer (A) obtained by polymerization of at least one (meth)acrylate monomer in the presence of at least one macromer selected from the group consisting of polymerizable ethylene-butylene, ethylene-propylene, ethylene-butylene-propylene and isobutylene macromers, and which forms a continuous acrylate phase and a discontinuous hydrocarbon phase Kw; a component (B) which is soluble in the hydrocarbon phase Kw of the comb copolymer (A) and comprises a plasticizer resin and a solid resin; the multiphase polymer composition (P) having a continuous acrylate phase with a static glass transition temperature Tg(Ac), measured by the DSC method, and a discontinuous hydrocarbon phase Kw1, comprising the hydrocarbon component (B) and having a static glass transition temperature Tg(Kw1), measured by the DSC method, where Tg(Kw1) is higher than Tg(Ac) by 35 to 60 kelvins.

16. Adhesive tape comprising a multilayer product of claim 1.

17. A method for adhesive bonding of articles, wherein said articles are bonded with a multilayer product of claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The process is elucidated in more detail below with reference to two figures, without any intention that the teaching according to the invention should be restricted unnecessarily by this exemplary representation. In the figures

(2) FIG. 1 shows an apparatus construction particularly useful for implementing the process, and

(3) FIG. 2 superimposed on the apparatus construction dealt with before, shows by way of example a locational assignment of the individual process steps and additionally, in particular, the parameters of temperature and pressure.

(4) The arrangement of the assemblies and process apparatus constituents, especially of the mixing assemblies, is presented by way of example, and can be varied according to the process regime.

(5) FIG. 1

(6) In a first assembly 1, as for example in a conveying assembly such as an extruder (more particularly a single-screw conveying extruder), the polymer forming the layer of the acrylate-based foam carrier (S) is melted and is conveyed, in particular by means of this conveying assembly 1, as a polymer melt, via a connecting section 11, more particularly a heatable connecting section 11 (for example, a hose or a pipe), into a second assembly 2, more particularly a mixing assembly such as a twin-screw extruder.

(7) Via one or more metering points 22, 23 in the second assembly, it is possible, jointly or separately from one another, for additives to be added to the base polymer melt, such as, for example, all the resins or some of the resins, the crosslinker system or parts thereof (more particularly crosslinker and/or accelerant), fillers, colour pastes or the like.

(8) Prior to departure from the assembly 2, in other words in particular from the twin-screw extruder, the polymer melt thus blended is degassed, more particularly via a vacuum dome V at a pressure of 175 mbar or less, and subsequently is conveyed via a second connecting section 24, more particularly a heatable connecting section 24 (for example, a hose or a pipe), into a third assembly 3, more particularly a second mixing assembly, as for example a planetary roller extruder provided with a sliding sealing ring 36.

(9) The third assembly 3, more particularly the planetary roller extruder, has one or more temperature-controllable mixing zones 31, 32 and one or more injection or metering facilities 33, 34, 35, for the polymer melt to be introduced and to be blended with further components and/or additives, the latter components and/or additives having more particularly already been degassed.

(10) Via a metering point 34, for example, a resin or a resin mixture is added. Advantageously the resin or resin mixture has been degassed beforehand in a separate vacuum dome V. Via a metering point 35 (here drawn in only schematically at the same point as 34, although it may well beand usually isa different metering point situated at a different point on the extruder), the microballoons embedded into a liquid are added. Via the same metering point or a further metering point, not shown in FIG. 1, the crosslinker system or parts thereof (in particular, hitherto absent components of the crosslinker system) may be added. Advantageously, the crosslinker system or parts thereofmore particularly crosslinker and/or accelerantmay be mixed in together with the microballoons, as a microballoon/crosslinker system mixture. In a heating zone 32 (heatable mixing zone), the polymer melt is compounded with the added components and/or additives, but at least with the microballoons.

(11) The resultant melt mixture is transferred via a further connecting section or a further conveying unit 37, such as a gear pump, for example, into a die 5. On departure from the die 5, in other words after a pressure drop, the incorporated microballoons undergo expansion, so giving rise to a foamed polymer composition, more particularly a foamed self-adhesive composition, which is subsequently shaped, being shaped, for example, as a web by means of a roll calender 4 (rolls 41, 42, and 43 of the calender; carrier material 44 onto which the polymer layer is deposited).

(12) FIG. 2

(13) The acrylate forming the layer of the acrylate-based foam carrier (S) is melted in a first assembly 1, as for example in a conveying assembly such as an extruder (more particularly a single-screw conveying extruder), and with this assembly is conveyed in the form of a polymer melt, via a heatable hose 11 or a similar connecting section (for example, a pipe), into a second assembly 2, as for example a mixing assembly such as a planetary roller extruder. In FIG. 2, by way of example for this, a modular-construction planetary roller extruder is provided which has four modules that can be temperature-controlled independently of one another (T.sub.1, T.sub.2, T.sub.3, T.sub.4).

(14) Via the metering port 22 it is possible for further components to be added, here in particular a melted resin or a melted resin mixture (for better miscibility, it may be advantageous to select a high temperature in the segment T.sub.2, and preferably in the segment T.sub.1 as well). There is also the possibility of supplying additional additives or fillers, such as colour pastes, for example, via further metering ports such as 22 present in the assembly 2 (not drawn in separately). At the metering point 23 it is possible with advantage to add the crosslinker. For this purpose it is advantageous to lower the temperature of the melt, in order to lower the reactivity of the crosslinker and thereby to increase the processing life (temperature in segment T.sub.4 low, advantageously low in the segment T.sub.3 as well).

(15) By means of a heatable hose 24b or a similar connecting section and a melt pump 24a or another conveying unit, the polymer melt is conveyed into a third assembly 3, such as a further mixing assembly, for example, such as a twin-screw extruder, and is fed into this assembly 3 at position 33. At the metering point 34, for example, the accelerant component is added. The design of the twin-screw extruder is advantageously such that it can be used as a degassing apparatus. Thus, for example, at the point shown, the entire mixture can be freed from all gas inclusions in a vacuum dome V at a pressure of 175 mbar or less. After the vacuum zone on the screw there is a blister B (a throttle point in the extrusion chamber, formed in particular as a circulating gap, such as an annular gap, for example, which serves, in particular, for adjusting the pressure of the melt processed in the extruder), which allows a build-up of pressure in the segment S that follows. Through appropriate control of the extruder speed and of the conveying unit downstream of the extruder, such as a melt pump 37a, for example, a pressure of 8 bar or more is built up in the segment S between blister B and melt pump 37a. In this segment S, at a metering point 35, the microballoon mixture (microballoons embedded into a liquid) is introduced, and is incorporated homogeneously into the polymer composition in the extruder.

(16) The resultant melt mixture is transferred by means of the conveying unit (melt pump 37a and a connecting section 37b, such as a hose, for example) into a die 5. On departure from the die 5, in other words after a drop in pressure, the incorporated microballoons undergo expansion, thereby forming a foamed polymer composition, more particularly a foamed carrier layer S, which is subsequently shaped, being shaped, for example, as a web by means of a roll calender 4.

(17) Furthermore, all of the chemical and physical foaming methods familiar to the skilled person may be used for converting the acrylate that forms the layer of the acrylate-based foam carrier (S) into a foam. Here, however, it should be ensured that the acrylate forming the layer of the acrylate-based foam carrier (S) remains thermally crosslinkable where necessary.

(18) In a further aspect, the present invention relates to a method for producing the multilayer products of the invention, which comprises (i) providing the herein-described layer of the acrylate-based foam carrier (S) having a top side and a bottom side; and (ii) applying the herein-described multiphase polymer composition (P) to the top side and/or bottom side of the foam carrier (S).

(19) Step (i) of the method of the invention here preferably comprises the following steps: (a) providing one or more acrylates and alkyl acrylates which are polymerizable by means of free or controlled radical polymerization; (b) polymerizing the acrylates and alkyl acrylates provided in method step (a), to form the herein-described polyacrylate; and (c) convertering the resulting polyacrylate into the herein-described polyacrylate foam, preferably foaming the resulting polyacrylate to form the polyacrylate foam, more preferably crosslinking and foaming or foaming and crosslinking the polyacrylate to form a crosslinked polyacrylate foam; and (d) shaping the polyacrylate foam into a layer of the herein-described foam carrier (S).

(20) In view of the herein-described suitability of the multiphase polymer composition (P) for the adhesive bonding of articles, more particularly for the adhesive bonding of articles having low-energy surfaces, the present invention further relates to an adhesive tape comprising the multilayer product of the invention, and also to the use of the multilayer product for adhesive bonding of articles, more particularly for adhesive bonding of surfaces with low energy.

(21) The multilayer products of the invention are particularly suitable for the adhesive bonding of different materials and components such as emblems, mouldings made of plastic (e.g. bumpers) and rubber seals on the bodywork of motor vehicles. Bonding in this case, in particular, is also possible only after a step of bodywork coating with an LSE varnish, thereby giving the surface of the bodywork the properties of low-energy materials.

(22) In the text below, the invention is illustrated in more detail with reference to specific examples.

EXAMPLES

(23) Measurement Methods (General):

(24) K Value (According to Fikentscher) (Method A1):

(25) The K value is a measure of the average molecule size in high-polymer compounds. For the measurement, one per cent strength (1 g/100 mL) toluenic polymer solutions were prepared, and their kinematic viscosities were determined using a Vogel-Ossag viscometer. Following standardization to the viscosity of toluene, the relative viscosity is obtained, and can be used to calculate the K value according to Fikentscher (Polymer 1967, 8, 381 ff.)

(26) Gel Permeation Chromatography GPC (Method A2):

(27) The figures in this specification for the weight-average molecular weight M.sub.w, and the polydispersity PD relate to the determination by gel permeation chromatography. The determination takes place on 100 L samples subjected to clarifying filtration (sample concentration 4 g/L). The eluent used is tetrahydrofuran with 0.1 vol % of trifluoroacetic acid. Measurement takes place at 25 C. The preliminary column used is a PSS-SDV column, 5, 10.sup.3 , ID 8.0 mm50 mm. Separation takes place using the columns PSS-SDV, 5, 10.sup.3 and also 10.sup.5 and 10.sup.6 , each of ID 8.0 mm300 mm (columns from Polymer Standards Service; detection using Shodex RI71 differential refractometer). The flow rate is 1.0 mL per minute. Calibration takes place against PMMA standards (polymethyl methacrylate calibration).

(28) Solids Content (Method A3):

(29) The solids content is a measure of the fraction of unevaporable constituents in a polymer solution. It is determined gravimetrically, with the solution being weighed, then the vaporizable fractions being evaporated off in a drying cabinet at 120 C. for 2 hours, and the residue weighed again.

(30) Static Glass Transition Temperature T.sub.g (Method A4):

(31) The static glass transition temperature is determined by dynamic scanning calorimetry in accordance with DIN 53765. The figures given for the glass transition temperature T.sub.g relate to the glass transformation temperature value T.sub.g according to DIN 53765:1994-03, unless indicated otherwise specifically.

(32) Density Determination by Pycnometer (Method A5a):

(33) The principle of the measurement is based on the displacement of the liquid located within the pycnometer. First, the empty pycnometer or the pycnometer filled with liquid is weighed, and then the body to be measured is placed into the vessel.

(34) The density of the body is calculated from the differences in weight:

(35) Let m.sub.0 be the mass of the empty pycnometer, m.sub.1 be the mass of the pycnometer filled with water, m.sub.2 be the mass of the pycnometer with the solid body, m.sub.3 be the mass of the pycnometer with the solid body, filled up with water, .sub.W be the density of the water at the corresponding temperature, .sub.F be the density of the solid body.

(36) The density of the solid body is then given by:

(37) ${}_F=\frac{\left(m_2-m_0\right)}{\left(m_1-m_0\right)-\left(m_3-m_2\right)}.Math.{}_W$

(38) One triplicate determination is carried out for each specimen. It should be noted that this method gives the unadjusted density (in the case of porous solid bodies, in the present case a foam, the density based on the volume including the pore spaces).

(39) Quick Method for Density Determination from the Coatweight and the Layer Thickness (Method A5b):

(40) The weight per unit volume or density p of the applied layer is determined via the ratio of the weight per unit area to the respective film thickness:

(41) $=\frac{m}{V}=\frac{\mathrm{MA}}{d}\left[\right]=\frac{\left[\mathrm{kg}\right]}{\left[m^2\right].Math.\left[m\right]}=\left[\frac{\mathrm{kg}}{m^3}\right]$

(42) MA=coatweight/weight per unit area (excluding liner weight) in [kg/m.sup.2]

(43) d=layer thickness (excluding liner thickness) in [m]

(44) This method as well gives the unadjusted density.

(45) This density determination is suitable in particular for determining the total density of finished products, including multi-layer products.

(46) Measurement Methods (PSAs Especially):

(47) 180 Bond Strength Test (Method H1):

(48) A strip 20 mm wide of an acrylate PSA applied to polyester as a layer was applied to a steel plate which beforehand had been washed twice with acetone and once with isopropanol. The pressure-sensitive adhesive strip was pressed onto the substrate twice with an applied pressure corresponding to a weight of 2 kg. The adhesive tape was then immediately removed from the substrate with a velocity of 300 mm/min and at an angle of 180. All measurements were conducted at room temperature.

(49) The results are reported in N/cm and have been averaged from three measurements. In the same way, determinations were made of the bond strength to polyethylene (PE) and varnish. The varnish usedfor examples measured by Method H2 as wellin each case was the Uregloss colourless varnish (product no. FF79-0060 0900) from BASF.

(50) 90 Bond Strength to SteelOpen and Lined Sides (Method H2):

(51) The bond strength to steel is determined under test conditions of 23 C.+/1 C. temperature and 50%+/5% relative atmospheric humidity. The specimens were cut to a width of 20 mm and adhered to a steel plate. Prior to the measurement, the steel plate is cleaned and conditioned. This is done by first wiping the plate with acetone and then leaving it to lie in the air for 5 minutes so that the solvent can evaporate. The side of the three-layer assembly facing away from the test substrate was then lined with a 50 m aluminium foil, to prevent the specimen stretching in the course of the measurement. After that, the test specimen was rolled onto the steel substrate. For this purpose, a 2 kg roller was passed five times back and forth over the tape with a rolling speed of 10 m/min. Immediately after rolling, the steel plate was inserted into a special mount which allows the specimen to be peeled off vertically upwards at an angle of 90. Bond strength measurement was carried out using a tensile tester from Zwick. When the lined side is applied to the steel plate, the open side of the three-layer assembly is first laminated to the 50 m aluminium foil, the release material is removed and the assembly is adhered to the steel plate, rolled analogously, and subjected to measurement.

(52) The results of measurement for both sides, open and lined, are reported in N/cm and have been averaged from three measurements.

(53) Holding Power (PSA on PET Film, Method H3):

(54) A strip of the adhesive tape 13 mm wide and more than 20 mm long (30 mm for example) was applied to a smooth steel surface which had been cleaned three times with acetone and once with isopropanol. The bonding area was 20 mm13 mm (lengthwidth), with the adhesive tape overhanging the test plate (for example by 10 mm in accordance with above-stated length of 30 mm). The adhesive tape was then pressed onto the steel support four times with an applied pressure corresponding to a weight of 2 kg. This sample was suspended vertically, so that the projecting end of the adhesive tape points downwards.

(55) At room temperature a weight of 1 kg was affixed to the projecting end of the adhesive tape. Measurement is conducted under standard conditions (23 C.+/1 C., 55%+/5% atmospheric humidity) and at 70 C. in a heating cabinet, the sample being loaded with a weight of 0.5 kg for this measurement.

(56) The holding powers measured (times which elapse before complete detachment of the adhesive tape from the substrate; measurement discontinued after 10 000 minutes) are reported in minutes and correspond to the average of three measurements.

(57) Holding PowerOpen and Lined Sides (Adhesive Tape Articles, Method H4):

(58) Preparation of specimens was carried out under test conditions of 23 C.+/1 C. temperature and 50%+/5% relative atmospheric humidity. The test specimen was cut to 13 mm and adhered to a steel plate. The bonding area is 20 mm13 mm (lengthwidth). Prior to the measurement the steel plate was cleaned and conditioned. This is done by first wiping the plate with acetone and then leaving it to lie in the air for 5 minutes to allow the solvent to evaporate. After bonding had been performed, the open side was reinforced with a 50 m aluminium foil and a 2 kg roller was passed twice back and forth over the assembly. A belt loop was then placed on the projecting end of the three-layer assembly. The system was then suspended from a suitable apparatus and subjected to a load of 10 N. The suspension apparatus is of a type such that the weight subjects the sample to load at an angle of 179+/1. This ensures that the three-layer assembly cannot peel from the bottom edge of the plate. The holding power measured, the time between the specimen being suspended and its fall, is reported in minutes and corresponds to the average from three measurements. For the measurement of the lined side, the open side is first reinforced with the 50 m aluminium foil, the release material is removed, and the specimen is adhered to the test plate in analogy to the description of the open side. The measurement is conducted under standard conditions (23 C., 55% humidity).

(59) Dynamic Shear Strength (Method H5):

(60) A square adhesive transfer tape with an edge length of 25 mm is bonded between two steel plates and pressed down for 1 minute at 0.9 kN (force P). After a storage time of 24 hours, the assembly is parted in a tensile testing machine from Zwick at 50 mm/min and at 23 C. and 50% relative humidity in such a way that the two steel plates are pulled apart from one another at an angle of 180 . The maximum force is determined in N/cm.sup.2.

(61) Chemical Resistance Particularly to 60/95 Spirit, Engine Oil and Diesel Fuel (Method H6):

(62) Sample preparation and measurement are as for Method H1. The specimen, already bonded, is placed in the investigation solvent, which has been conditioned at 23 C., for 10 minutes. The specimen is then taken from the solvent bath and wiped down, and the residual solvent is evaporated over 10 minutes, after which the bond strength is measured by comparison with a sample of the same adhesive tape which had the same contact time with the substrate that was not kept in a solvent.

(63) The table below contains the commercially available chemicals used in the examples described here.

(64) TABLE-US-00001 Chemical compound Trade name Manufacturer CAS No. 1,3-Butadiene, homopolymer, L-1253 Kuraray 260057-97-4 hydrogenated, hydroxy- terminated, monomethacrylate Isostearyl acrylate ISTA ISA Co., Ltd. 93841-48-6 2,2-Azobis(2-methylbutyronitrile) Vazo 67 DuPont 13472-08-7 Bis(4-tert-butylcyclohexyl)peroxydicarbonate Perkadox 16 Akzo Nobel 15520-11-3 Aluminium acetylacetonate Sigma-Aldrich 13963-57-0 Liquid hydrocarbon resin (C.sub.5- Wingtack 10 Cray Valley 26813-14-9 based) Hydrocarbon resin (C.sub.5-based, low Piccotac 1095-N Eastman aromatics fraction, softening point (Ring & Ball) 94 C.) Hydrogenated liquid polyisoprene LIR-290 Kuraray 151789-04-7 SBS (about 16 wt % diblock, block Kraton D 1101 Kraton Polymers 9003-55-8 polystyrene content: 31 wt %) SBS (about 76 wt % diblock, block Kraton D 1118 E Kraton Polymers 9003-55-8 polystyrene content: 31 wt %) Hydrocarbon resin (C.sub.5- and C.sub.9- Escorez 2203 Exxon Mobil 64742-16-1 based with low aromatics fraction, softening point (Ring & Ball) about 95 C.) Naphthenic oil Shellflex 371 Shell 64742-2-5 2,2-Azobis(isobutyronitrile) Vazo 64 DuPont 78-67-1 (AIBN) 3,4-Epoxycyclohexylmethyl 3,4- Uvacure 1500 Cytec Industries 2386-87-0 epoxycyclohexanecarboxylate Inc. Resorcinol bis(diphenyl Reofos RDP Chemtura 57583-54-7 phosphate) Pentaerythritol tetraglycidyl ether Polypox R16 UPPC AG 3126-63-4 N-(3-(Dimethylamino)propyl)- Jeffcat Z-130 Huntsman 6711-48-4 N,N-dimethyl-1,3- propanediamine Microballoons (MB) Expancel 051 DU Expancel Nobel (Dry-unexpanded microspheres, 40 Industries diameter 9-15 m, expansion initiation temperature 106-111 C., TMA density 25 kg/m.sup.3)

I Preparation of the Comb Compolymers (A)P 1 to P 4

(65) Described below is the preparation of exemplary comb copolymers (A).

Example P 1

(66) A 100 L glass reactor conventional for radical polymerizations was charged with 1.2 kg of acrylic acid (AA, 3%), 20.97 kg of 2-ethylhexyl acrylate (EHA, 52.43%), 9.83 kg of butyl acrylate (BA, 24.57%), 4.0 kg of isobornyl acrylate (IBOA, 10%), 4.0 kg of macromer L-1253 (10%) and 20.8 kg of acetone/60/95 spirit (1:1). After nitrogen gas had been passed through the reactor for 45 minutes, with stirring, the reactor was heated up to 58 C. and 0.8 kg of Vazo 67 was added. Thereafter the external heating bath was heated to 75 C. and the reaction was carried out constantly at this external temperature. After a reaction time of 1 hour, a further 0.8 kg of Vazo 67 was added. Over a period of 5 hours (counted from the last addition of Vazo 67), dilution took place at hourly intervals with 5.0 to 10.0 kg, depending on the rise in viscosity, of 60/95 spirit, and so adequate mixing was ensured. In order to reduce the level of residual monomers, additions of 1.5 kg each time of bis(4-tert-butylcyclohexyl) peroxydicarbonate were made after 6 hours and after 7 hours from the start of reaction (i.e. counting from the first addition of Vazo 67), with dilution in between with 15 kg of 60/95 spirit. After a reaction time of 24 hours, the reaction was discontinued by cooling to room temperature.

(67) Comb Popolymers (A)P 2 to P 4

(68) Comb copolymers P 2 to P 4 were prepared as for Example P 1. The percentage mass figures of each of the monomers used are listed in Table 1. Ethyl acetate was used both for polymerization of hybrid polymer P 3 and for all dilutions carried out during the preparation of P 3.

(69) TABLE-US-00002 TABLE 1 Hybrid polymers P2 to P4 AA BA EHA IBOA ISTA L-1253 P 2 3.0% 26.9% 60.1% 10.0% P 3 5.0% 25.5% 54.5% 15.0% P 4 5.0% 25.5% 54.5% 5.0% 10.0%

(70) Table 2 shows the molar mass distributions as measured by GPC and the static glass transition temperatures as measured by DSC for hybrid polymers P 1 to P 4.

(71) TABLE-US-00003 TABLE 2 Polymer data for hybrid polymers P 1 to P 4 stat. Tg.sub.1 stat. Tg.sub.2 M.sub.n [g/mol].sup.a) M.sub.w [g/mol].sup.a) PD [].sup.a) [ C.].sup.b) [ C.].sup.b) P 1 64 800 1 570 000 24.23 67.7 39.6 P 2 64 900 1 550 000 23.88 67.7 50.5 P 3 68 500 1 620 000 23.65 67.7 49.4 P 4 58 100 1 620 000 27.88 53.4 49.9 .sup.a)Measured by Method A2. .sup.b)Measured by Method A4.

II Preparation of Multiphase Polymer Compositions (P)PSA 1 to PSA 4 and of Comparative Compositions VPSA 5 to VPSA 7

(72) Described below is the preparation of exemplary multiphase polymer compositions (P). All examples PSA 1 to PSA 4 and also comparative examples VPSA 5 to VPSA 7 were prepared in solution, then coated onto a 36 m PET film (Kemafoil HPH 100, Covema) or onto a siliconized release film for lamination to a layer of an acrylate-based foam carrier, and subsequently dried. The coatweight was 50 g/m.sup.2 in each case.

(73) The multiphase polymer compositions PSA 1 to PSA 4 and also comparative example VPSA 5, based on an acrylate-hydrocarbon hybrid polymer, were prepared in solution from the hybrid polymers P 1 to P 4. For this purpose, they were diluted to a solids content of 30% with spirit, 0.3 wt % of the aluminum acetylacetonate crosslinker, and the resin or resins according to Table 3, were added to the solution, followed by coating and subsequent drying. For coating and drying an apparatus was used in which a drying tunnel with different temperature zones was located after a comma bar (coating rate 2.5 m/min, drying tunnel 15 m, temperatureszone 1: 40 C., zone 2: 70 C., zone 3: 95 C., zone 4: 105 C.).

(74) The resin fractions and glass transition temperatures of the acrylate phase and hydrocarbon phase of the multiphase polymer composition (P) are listed in Table 3; the technical adhesive data for examples PSA 1 to PSA 4 and also comparative examples VPSA 5 to VPSA 7 are listed in Table 4.

(75) TABLE-US-00004 TABLE 3 Hybrid examples PSA 1 to PSA 4 and comparative example VPSA 5 Hydrocarbon Hydrocarbon Solid HC Piccotac fraction, fraction, resin fraction, stat. stat. 1095-N Wingtack 10 LIR-290 total on macromer on total resin Tg HC phase Tg Ac phase Tg Polymer [%] [%] [%] [%] [%] [%] [ C.].sup.b) [ C.].sup.b) [K] PSA 1 P1 30.0 16.0 10.0 56.0 92.7 65.2 1 39.6 40.6 PSA 2 P2 27.9 23.2 51.1 91.4 54.6 6.3 50.5 56.8 PSA 3 P3 30.3 23.0 53.3 86.9 56.8 6.4 49.4 55.8 PSA 4 P4 30.3 23.0 53.3 86.9 56.8 6.4 49.9 56.3 VPSA 5 P1 16.3 30.0 46.3 88.4 35.2 6.0 39.9 33.9 .sup.b)Measured by Method A4.

Comparative Example

Crosslinked Synthetic Rubber PSA (VPSA 6)

(76) For comparative example PSA 5, 33.0 kg of Kraton D 1101, 17 kg of Kraton D 1118, 48.0 kg of Escorez 2203 hydrocarbon resin and 2.0 kg of Shellflex 371 oil were dissolved in 100 kg of toluene. After coating out (film thickness: 50 g/m.sup.2) and drying, the material was additionally crosslinked by means of electron beam curing (EBC). This electron beam curing was done using a unit from Electron Crosslinking AB (Halmstad, Sweden) and using an accelerator voltage of 220 keV and also a dose of 35 kGy with a belt speed of 3 m/min.

Comparative Example

Polyacrylate PSA (VPSA 7)

(77) A 100 L glass reactor conventional for radical polymerizations was charged with 2.0 kg of acrylic acid, 25.0 kg of butyl acrylate, 13.0 kg of 2-ethylhexyl acrylate and 26.7 kg of acetone/ 60/95 spirit (1:1). After nitrogen gas had been passed through the reactor for 45 minutes with stirring, the reactor was heated up to 58 C. and 30 g of AIBN were added. After that the external heating bath was heated to 75 C. and the reaction was carried out constantly at this external temperature. After a reaction time of 1 hour a further 30 g of AIBN were added. After 4 hours and 8 hours, dilution took place with 10 kg of acetone/60/95 spirit (1:1) mixture each time. In order to reduce the level of residual initiators, 90 g portions of bis(4-tert-butylcyclohexyl) peroxydicarbonate were added after 8 hours and again after 10 hours. The reaction was terminated after a time of 24 hours by cooling to room temperature. The resulting polyacrylate had a K value of 49.3, an average molecular weight of M.sub.w=1 058 800 g/mol, a polydispersity of D (M.sub.w/M.sub.n)=15.1 and a static glass transition temperature of Tg=15.3 C. The polyacrylate was subsequently blended with 0.2 wt % of Uvacure 1500, diluted to a solids content of 30% with acetone, and then coated from solution onto a siliconized release film (50 m polyester) or onto a 23 m, etched PET film. (Coating rate 2.5 m/min, drying tunnel 15 m, temperatureszone 1: 40 C., zone 2: 70 C., zone 3: 95 C., zone 4: 105 C.). The coatweight was 50 g/m.sup.2.

(78) TABLE-US-00005 TABLE 4 Technical adhesive data for multiphase polymer compositions (P) - PSA 1 to PSA 4 and comparative examples VPSA 5 to VPSA 7 BS instant. steel BS instant. FF-79 BS instant. PE HP RT Ex. [N/cm] [N/cm] [N/cm] [min] PSA 1 9.65 6.2 6.12 >10 000 PSA 2 12.79 10.52 5.89 >10 000 PSA 3 15.74 15.39 7.56 7200 (K) PSA 4 15.36 14.99 7.87 7108 (K) VPSA 5 8.63 6.7 4.42 3682 (A) VPAS 6 3.8 1.2 0.5 >10 000 VPSA 7 4.4 1.3 1.0 >10 000 The bond strength (BS) measurements, instantaneous, took place by Method H1; the holding power (HP) time measurements at room temperature took place by Method H3. A: adhesive fraction, K: cohesive fracture.

III Preparation of Exemplary Polyacrylates for the Layer of the Acrylate-based Foam Carrier (S)VT 1 and VT 2

(79) Described below is the preparation of the starting polymers. The polymers investigated are prepared conventionally in solution via a free radical polymerization.

(80) Polyacrylate VT 1

(81) A reactor conventional for radical polymerizations was charged with 54.4 kg of 2-ethylhexyl acrylate, 20.0 kg of methyl acrylate, 5.6 kg of acrylic acid and 53.3 kg of acetone/isopropanol (94:6). After nitrogen gas had been passed through the reactor for 45 minutes, with stirring, the reactor was heated up to 58 C. and 40 g of 2,2-azobis(2-methylbutyronitrile) were added. Thereafter the external heating bath was heated to 75 C. and the reaction was carried out constantly at this external temperature. After 1 hour a further 40 g of 2,2-azobis(2-methylbutyronitrile) were added and after 4 hours dilution took place with 10 kg of acetone/isopropanol mixture (94:6). After 5 hours and again after 7 hours, re-initiation was carried out with 120 g of bis(4-tert-butylcyclohexyl) peroxydicarbonate. After a reaction time of 22 hours, cooling took place to room temperature. The polyacrylate has a K value of 58.8, a solids content of 55.9%, an average molecular weight of M.sub.w=746 000 g/mol, polydispersity (M.sub.w/M.sub.n)=8.9 and a static glass transition temperature of T.sub.g=11.0 C.

(82) Polyacrylate VT 2

(83) A reactor conventional for radical polymerizations was charged with 30 kg of 2-ethylhexyl acrylate, 67 kg of n-butyl acrylate, 3 kg of acrylic acid and 66 kg of acetone/isopropanol (96:4). After nitrogen gas had been passed through the reactor for 45 minutes, with stirring, the reactor was heated up to 58 C. and 50 g of 2,2-azobis(2-methylbutyronitrile) were added. Thereafter the external heating bath was heated to 75 C. and the reaction was carried out constantly at this external temperature. After 1 hour a further 50 g of 2,2-azobis(2-methylbutyronitrile) were added and after 4 hours dilution took place with 20 kg of acetone/isopropanol mixture (96:4).

(84) After 5 hours and again after 7 hours, re-initiation was carried out with 150 g of bis(4-tert-butylcyclohexyl) peroxydicarbonate, and dilution with 23 kg of acetone/isopropanol mixture (96:4). After a reaction time of 22 hours the polymerization was discontinued by cooling to room temperature. The polyacrylate has a K value of 75.1, a solids content of 50.2%, an average molecular weight of M.sub.w=1 480 000 g/mol, polydispersity (M.sub.w/M.sub.n)=16.1 and a static glass transition temperature of T.sub.g=38.5 C.

(85) IV Production of Microballoon Mixtures

(86) The microballoons are placed in a container which has been charged with Reofos RDP as liquid component (dispersant) as reported in the individual examples. Stirring then took place in a planetary stirrer mechanism from PC-LABORSYSTEM under a pressure of 5 mbar with a rotary speed of 600 rpm for 30 minutes.

(87) Process 1: Concentration/Preparation of the Polyacrylate Melt

(88) The acrylate copolymers (base polymers VT 1 and VT 2) are very largely freed from the solvent by means of a single-screw extruder (feeder extruder 1, Troester GmbH & Co KG, Germany) (residual solvent content 0.3 wt %; cf. the individual examples). The parameters given here by way of example are those for the concentration of polyacrylate VT 1. The screw speed was 150 rpm, the motor current 15 A, and a throughput of 60.0 kg liquid/h was realized. For concentration, a vacuum was applied at three different domes. The reduced pressures were, respectively, between 20 mbar and 300 mbar. The exit temperature of the concentrated hotmelt is approximately 115 C. The solids content after this concentration step was 99.8%.

(89) Process 2: Preparation of Foamed Composition

(90) Foaming takes place in an experimental unit which corresponds to the illustration in FIG. 2.

(91) The corresponding polyacrylate (VT 1 and VT 2) is melted as per Process 1 in a feeder extruder 1 and is conveyed by this extruder, in the form of a polymer melt, via a heatable hose 11 into a planetary roller extruder 2 (PRE) from Entex (Bochum) (more particularly a PRE with four modules heatable independently of one another, T.sub.1, T.sub.2, T.sub.3 and T.sub.4, was used). Via the metering port 22, there exists the possibility of supplying additional additives or fillers, such as colour pastes, for example. At point 23, the crosslinker is added. All of the components are mixed to form a homogeneous polymer melt.

(92) By means of a melt pump 24a and a heatable hose 24b, the polymer melt is transferred into a twin-screw extruder 3 (from Berstorff) (feed position 33). At position 34, the accelerator component is added. Subsequently the mixture as a whole is freed from all of the gas inclusions in a vacuum dome V at a pressure of 175 mbar (for the criterion for freedom from gas, see above). Downstream of the vacuum zone, on the screw, there is a blister B, which allows a build-up of pressure in the subsequent segment S. Through appropriate control of the extruder speed and of the melt pump 37a, a pressure of greater than 8 bar is built up in the segment S between blister B and melt pump 37a, and at the metering point 35 the microballoon mixture (microballoons embedded into the dispersing assistant in accordance with the details given for the experimental series) is added, and is incorporated homogeneously into the premix by means of a mixing element. The resultant melt mixture is transferred into a die 5.

(93) Following departure from the die 5, in other words after a drop in pressure, the incorporated microballoons undergo expansion, and the drop in pressure results in a low-shear, more particularly no-shear, cooling of the polymer composition. This produces an acrylate-based foam which subsequently, to form a layer of an acrylate-based foam carrier (S), is coated between two release materials, more particularly between a release material which can be used again after being removed (in-process liner), and is shaped to a web by means of a roll calender 4.

(94) TABLE-US-00006 TABLE 5 Viscoelastic acrylate-based foam carriers VT 1 and VT 2 Example VT 1 VT 2 Components Polyacrylate [wt %] 97.8 97.1 Expancel 051 DU 40 1.5 2.0 Polypox R16 0.139 0.222 Jeffcat Z130 0.144 0.154 Reofos RDP 0.41 0.48 Construction Thickness [m] 1092 1124 Density (I.2) [kg/m.sup.3] 749 670 Performance HP [min] RT 20 N [min] 1874 5232 70 C. 10 N 1282 2954 Bond strength to steel [N/cm] instantaneous [N/cm] 24.5 A 21.0 A 3 d 33.4 A 64.3 K 14 d 35.1 A 65.2 K Density: Method A5a, bond strength: Method H2, HP (holding power): Method H4
V Multilayer Products MT 1 to MT 8; Comparative Examples VMT 9 to VMT 11

(95) In all examples, both sides of the acrylate-based foam carriers were coated with the same PSA. The coatweight of the respective multiphase polymer composition on the viscoelastic carrier is in all cases 50 g/m.sup.2.

(96) In order to improve the anchoring of the PSA on the shaped, viscoelastic carrier layer, not only the PSA but also the viscoelastic carrier are corona-treated prior to the laminating step (corona unit from Vitaphone, Denmark, 100 W.Math.min/m.sup.2). After the three-layer assembly has been produced, this treatment leads to improved chemical attachment to the viscoelastic carrier layer. The web speed when travelling through the laminating unit is 30 m/min. Prior to lamination, any anti-adhesive support, more particularly an in-process liner, is removed, and the completed three-layer product is wound up together with a remaining, second anti-adhesive support.

(97) Presented below are specific examples of the inventive multilayer products (MT) and also non-inventive comparative products (VMT), without any intention to impose unnecessary restriction on the invention by the choice of the specified formulations, configurations, operational parameters and/or product designs.

(98) TABLE-US-00007 TABLE 6 Examples MT 1 to MT 8 and comparative examples VMT 9 to VMT 11 BS to varnish FF- HP 10 N, HP 10 N, Dyn. shear Viscoel. BS to steel BS to PE 79 RT 70 C. strength Ex. PSA carrier [N/cm] [N/cm] [N/cm] [min] [min] [N/cm.sup.2] MT 1 PSA 1 VT 1 50 f.s. 48 50 f.s. >10 000 >10 000 60 MT 2 PSA 1 VT 2 50 f.s. 49 50 f.s. >10 000 1200 63 MT 3 PSA 2 VT 1 50 f.s. 47 42 >10 000 >10 000 44 MT 4 PSA 2 VT 2 50 f.s. 48 50 f.s. >10 000 5200 54 MT 5 PSA 3 VT 1 50 f.s. 48 50 f.s. >10 000 >10 000 65 MT 6 PSA 3 VT 2 50 f.s. 50 f.s. 50 f.s. >10 000 >10 000 68 MT 7 PSA 4 VT 1 50 f.s. 42 42 >10 000 >10 000 60 MT 8 PSA 4 VT 2 50 f.s. 46 45 >10 000 2200 44 VMT 9 VPSA 5 VT 2 50 f.s. 34 44 >10 000 5500 52 VMT 10 VPSA 6 VT 2 41 23 41 7500 (A) 380 (A) 65 VMT 11 VPSA 7 VT 2 25 10 23 >10 000 2200 41 Bond strength (BS): Method H2, HP (holding power): Method H4, dynamic shear strength: Method H5, A: Adhesive fracture f.s.: foam split (cohesive splitting of the viscoelastic carrier)
VI Peel Increase Behaviour of the Three-Layer Products MT 6 and Comparative Examples VMT 9 to VMT 11

(99) TABLE-US-00008 TABLE 7 Peel increase behaviour BS to PE instan. BS to PE 20 min BS to PE 1 d BS to PE 3 d BS to FF-79 BS to FF-79 BS to FF-79 1 d BS to FF-79 3 d Ex. [N/cm] [N/cm] [N/cm] [N/cm] instan. [N/cm] 20 min [N/cm] [N/cm] [N/cm] MT 6 50 f.s. 50 f.s. 50 f.s. 50 f.s. 50 f.s. 50 f.s. 50 f.s. 50 f.s. VMT 9 34 38 39 39 44 49 50 f.s. 50 f.s. VMT 10 23 30 30 30 41 50 f.s. 50 f.s. 50 f.s. VMT 11 10 18 26 35 23 35 42 79 Bond strength (BS): Method H2, f.s.: foam split (cohesive splitting of the viscoelastic carrier)
VII Stability of the Three-Layer Products MT 6 and Also of Comparative Examples VMT 9 to VMT 11 Towards 60/95 Spirit

(100) TABLE-US-00009 TABLE 8 Spirit stability BS steel without BS steel after Bond strength spirit storage spirit storage reduction Spirit Ex. [N/cm] [N/cm] [%] stability MT 6 50 f.s. 44 12.0 very good VMT 9 50 f.s. 38 24.0 good VMT 10 41 2 95.1 poor VMT 11 25 22 12.0 very good Measurement method H5, f.s.: foam split (cohesive splitting in viscoelastic carrier)
Preferred Embodiments of the Invention

(101) Summarized below are particularly preferred embodiments of the invention, in the form of embodiments EMB 1 to EMB 31:

(102) EMB 1. Multilayer product comprising at least one layer of an acrylate-based foam carrier (S); and a multiphase polymer composition (P) applied to this layer;
the multiphase polymer composition (P) comprising: a comb copolymer (A) which is obtainable by polymerization of at least one (meth)acrylate monomer in the presence of at least one macromer selected from the group consisting of polymerizable ethylene-butylene, ethylene-propylene, ethylene-butylene-propylene and isobutylene macromers, and which forms a continuous acrylate phase and a discontinuous hydrocarbon phase Kw; and at least one hydrocarbon component (B) which is soluble in the hydrocarbon phase Kw of the comb copolymer (A) and comprises at least one plasticizer resin and at least one solid resin;
the multiphase polymer composition (P) having a continuous acrylate phase with a static glass transition temperature Tg(Ac), measured by the DSC method, and a discontinuous hydrocarbon phase Kw1, comprising the hydrocarbon component (B) and having a static glass transition temperature Tg(Kw1), measured by the DSC method, where Tg(Kw1) is higher than Tg(Ac) by 35 to 60 kelvins, preferably by 40 to 60 kelvins, more preferably by 45 to 60 kelvins.

(103) EMB 2. Multilayer product according to EMB 1, the acrylate-based foam carrier (S) being a viscoelastic foam carrier.

(104) EMB 3. Multilayer product according to either of preceding EMB 1 and EMB 2, the acrylate forming the layer of the foam carrier (S) being a polyacrylate which is obtainable by free or controlled radical polymerization of one or more acrylates and alkyl acrylates.

(105) EMB 4. Multilayer product according to any of preceding EMB 1 to EMB 3, the acrylate forming the layer of the foam carrier (S) being a crosslinked polyacrylate, preferably a thermally crosslinked polyacrylate.

(106) EMB 5. Multilayer product according to any of preceding EMB 1 to EMB 4, the acrylate forming the layer of the foam carrier (S) being a polyacrylate which is obtainable by polymerization of monomers consisting of monomers of the following groups (a1) to (a3):

(107) (a1) 70 to 100 wt %, based on all monomers participating in the polymerization, of acrylic esters and/or methacrylic esters and/or a free acid as per structural formula (I):

(108) ##STR00003##
where R.sup.1 is H or CH.sub.3 and R.sup.2 represents H or C.sub.1-C.sub.14 alkyl;

(109) (a2) 0 to 30 wt %, based on all monomers participating in the polymerization, of olefinically unsaturated monomers which are copolymerizable with the monomers of group (a1) and have at least one functional group; and

(110) (a3) optionally further acrylates and/or methacrylates and/or olefinically unsaturated monomers, preferably in a fraction of 0 to 5 wt %, based on all monomers participating in the polymerization, which are copolymerizable with the monomers of group (a1) and have at least one functional group which leads by means of a coupling reagent to covalent crosslinking.

(111) EMB 6. Multilayer product according to EMB 5, the monomers of group (a1) being selected from methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, n-butyl acrylate, n-butyl methacrylate, n-pentyl acrylate, n-hexyl acrylate, n-hexyl methacrylate, n-heptyl acrylate, n-octyl acrylate, n-nonyl acrylate, lauryl acrylate, stearyl acrylate, stearyl methacrylate, behenyl acrylate and their branched isomers such as, for example, 2-ethylhexyl acrylate, and also mixtures thereof; and/or the monomers of group (a2) being selected from maleic anhydride, itaconic anhydride, glycidyl methacrylate, benzyl acrylate, benzyl methacrylate, phenyl acrylate, phenyl methacrylate, tert-butylphenyl acrylate, tert-butylphenyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, 2-butoxyethyl methacrylate, 2-butoxyethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, diethylaminoethyl methacrylate, diethylaminoethyl acrylate and tetrahydrofurfuryl acrylate, and also mixtures thereof; and/or the monomers of group (a3) being selected from hydroxyethyl acrylate, 3-hydroxypropyl acrylate, hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, allyl alcohol, itaconic acid, acrylamide and cyanoethyl methacrylate, cyanoethyl acrylate, 6-hydroxyhexyl methacrylate, N-tert-butylacrylamide, N-methylolmethacrylamide, N-(butoxymethyl)methacrylamide, N-methylolacrylamide, N-(ethoxymethyl)acrylamide, N-isopropylacrylamide, vinylacetic acid, -acryloyloxpropionic acid, trichloroacrylic acid, fumaric acid, crotonic acid, aconitic acid, dimethylacrylic acid and 4-vinylbenzoic acid, and also mixtures thereof.

(112) EMB 7. Multilayer product according to any of preceding EMB 1 to EMB 6, the multilayer product being an adhesive tape.

(113) EMB 8. Multilayer product according to any of EMB 5 to EMB 7, the monomers of groups (a1) to (a3) being selected such that the static glass transition temperature, Tg(A), measured by the DSC method, of the acrylate forming the layer of the foam carrier (S) is 15 C. or less.

(114) EMB 9. Multilayer product according to any of preceding EMB 1 to EMB 8, the layer of the foam carrier (S) comprising at least one tackifying resin in addition to the acrylate forming this layer.

(115) EMB 10. Multilayer product according to any of preceding EMB 1 to EMB 9, the layer of the foam carrier (S) being foamed through use of microballoons.

(116) EMB 11. Multilayer product according to any of preceding EMB 1 to EMB 10, the layer of the foam carrier (S) having a layer thickness of 0.3 to 5 mm.

(117) EMB 12. Multilayer product according to any of preceding EMB 1 to EMB 11, the static glass transition temperature of the discontinuous hydrocarbon phase Kw1 within the polymer composition (P), Tg(Kw1), being in a range from 5 to +15 C., preferably 0 to +10 C.

(118) EMB 13. Multilayer product according to any of preceding EMB 1 to EMB 12, the static glass transition temperature of the continuous acrylate phase within the polymer composition (P), Tg(Ac), being below 10 C., preferably in a range from 60 to 20 C., more preferably in a range from 50 to 30 C.

(119) EMB 14. Multilayer product according to any of preceding EMB 1 to EMB 13, the macromer having a number-average molecular weight Mn, measured by the GPC method, of 1000 to 500 000 g/mol, preferably of 2000 to 30 000.

(120) EMB 15. Multilayer product according to any of preceding EMB 1 to EMB 14, the fraction of the comb copolymer (A) making up 30-64 weight percent, preferably 45-60 weight percent, based on the total weight of the comb copolymer (A) and of the at least one hydrocarbon component (B) within the polymer composition (P).

(121) EMB 16. Multilayer product according to any of preceding EMB 1 to EMB 15, the macromer units within the comb copolymer (A) making up 5-25 weight percent, preferably 10-15 weight percent, based on the total weight of the comb copolymer (A).

(122) EMB 17. Multilayer product according to any of preceding EMB 1 to EMB 16, the at least one (meth)acrylate monomer which can be used for preparing the comb copolymer (A) comprising at least one monomer which is selected from the group consisting of acrylic acid, methacrylic acid, 2-ethylhexyl acrylate, methyl acrylate, butyl acrylate, isobornyl acrylate, stearyl acrylate, isostearyl acrylate, amyl acrylate, isooctyl acrylate, decyl acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate and 4-hydroxybutyl acrylate, preferably from the group consisting of acrylic acid, methacrylic acid, 2-ethylhexyl acrylate, methyl acrylate, butyl acrylate, isobornyl acrylate, stearyl acrylate, isostearyl acrylate, amyl acrylate, isooctyl acrylate and decyl acrylate.

(123) EMB 18. Multilayer product according to any of preceding EMB 1 to EMB 17, the polymerization of the at least one (meth)acrylate monomer which can be used for preparing the comb copolymer (A) being carried out in the presence of at least one further copolymerizable monomer, this at least one further copolymerizable monomer being selected from the group consisting of itaconic acid, itaconic anhydride, maleic acid, maleic anhydride, vinyl acetate, vinyl butyrate, vinyl propionate, vinyl isobutyrate, vinyl valerate, vinyl versatates, N-vinylpyrrolidone and N-vinylcaprolactam.

(124) EMB 19. Multilayer product according to any of preceding EMB 1 to EMB 18, the comb copolymer (A) being obtainable by polymerization of a comonomer mixture comprising acrylic acid, butyl acrylate and 2-ethylhexyl acrylate in the presence of the at least one macromer.

(125) EMB 20. Multilayer product according to any of preceding EMB 1 to EMB 19, the polymerization of the at least one (meth)acrylate monomer which can be used for preparing the comb copolymer (A) being carried out in the presence of at least one further non-polyolefinic macromer, the further non-polyolefinic macromer being preferably selected from the group of the polymethacrylates, polystyrenes, polydimethylsiloxanes, polyethylene oxides and polypropylene oxides.

(126) EMB 21. Multilayer product according to any of preceding EMB 1 to EMB 20, the plasticizer resin and the solid resin of the hydrocarbon component (B) of the polymer composition (P) having a number-average molecular weight Mn of 1000 g/mol or less, measured by the GPC method.

(127) EMB 22. Multilayer product according to any of preceding EMB 1 to EMB 21, the hydrocarbon component (B) of the polymer composition (P) consisting of a plasticizer resin and a solid resin.

(128) EMB 23. Multilayer product according to any of preceding EMB 1 to EMB 22, the polymer composition (P) further comprising a further hydrocarbon compound (C), whose number-average molecular weight Mn, measured by the GPC method, is more than 1000 g/mol, and the polymer composition preferably having a static glass transition temperature Tg(C) which lies between the glass transition temperatures of the continuous acrylate phase, Tg(Ac), and of the discontinuous hydrocarbon phase, Tg(Kw1).

(129) EMB 24. Multilayer product according to any of preceding EMB 1 to EMB 23, the polymer composition (P) further comprising at least one additive selected from the group consisting of plasticizers, oils and resins soluble in the acrylate phase of the comb copolymer, preferably rosin esters and/or terpene-phenolic resins.

(130) EMB 25. Multilayer product according to any of preceding EMB 1 to EMB 24, the total amount of the hydrocarbon component (B) and, if present, of the hydrocarbon compound (C) of the polymer composition (P) being 80 weight percent or more, based on the total fraction of the discontinuous hydrocarbon phase within the polymer composition (P).

(131) EMB 26. Multilayer product according to any of preceding EMB 1 to EMB 25, the polymer composition (P) being a pressure-sensitive adhesive.

(132) EMB 27. Multilayer product according to any of preceding EMB 1 to EMB 26, the multiphase polymer composition (P) applied to the layer of the foam carrier (S) being applied in the form of a layer having a weight per unit area of 40 to 100 g/m.sup.2.

(133) EMB 28. Method for producing a multilayer product according to any of preceding EMB 1 to EMB 27, comprising the steps of: (i) providing a layer of an acrylate-based foam carrier (S) having a top side and a bottom side; and (ii) applying a multiphase polymer composition (P) to the top side and/or bottom side of the foam carrier (S),
the multiphase polymer composition (P) comprising: a comb copolymer (A) which is obtainable by polymerization of at least one (meth)acrylate monomer in the presence of at least one macromer selected from the group consisting of polymerizable ethylene-butylene, ethylene-propylene, ethylene-butylene-propylene and isobutylene macromers, and which forms a continuous acrylate phase and a discontinuous hydrocarbon phase Kw; and at least one hydrocarbon component (B) which is soluble in the hydrocarbon phase Kw of the comb copolymer (A) and comprises at least one plasticizer resin and at least one solid resin;
the multiphase polymer composition (P) having a continuous acrylate phase with a static glass transition temperature Tg(Ac), measured by the DSC method, and a discontinuous hydrocarbon phase Kw1, comprising the hydrocarbon component (B) and having a static glass transition temperature Tg(Kw1), measured by the DSC method, where Tg(Kw1) is higher than Tg(Ac) by 35 to 60 kelvins, preferably by 40 to 60 kelvins, more preferably by 45 to 60 kelvins.

(134) EMB 29. Method according to EMB 28, step (i) comprising the following method steps: (a) providing one or more acrylates and alkyl acrylates which are polymerizable by means of free or controlled radical polymerization; (b) polymerizing the acrylates and alkyl acrylates provided in method step (a), to form a polyacrylate; (c) converting the resulting polyacrylate into a polyacrylate foam; and (d) shaping the polyacrylate foam into a layer of a foam carrier (S).

(135) EMB 30. Adhesive tape comprising a multilayer product according to any of EMB 1 to EMB 27.

(136) EMB 31. Use of the multilayer product according to any of EMB 1 to EMB 27 for adhesive bonding of articles.