Abstract:
The invention provides meltable and UV-crosslinkable pressure-sensitive adhesives, such as acrylate hotmelts or hotmelt formulations, which can be processed by commonplace hotmelt processes and also on customary hotmelt coating lines, without any immediate alteration in the product properties in the event of (unwanted) deviation in the operational parameters. The compositions of the invention are UV-crosslinkable and meltable pressure-sensitive adhesives comprising (i) mixtures of UV-crosslinkable polyacrylate polymers selected from a) mixtures of UV-crosslinkable polymers with at least one photoinitiator bonded covalently to the backbone of the polymers, and b) mixtures of UV-crosslinkable polyacrylate polymers, monomers and at least one photoinitiator, and also (ii) at least one UV stabilizer, and also methods for producing them and the use thereof as bonding agents.
Abstract:
End-group-functionalized oligomers with controlled degrees of functionality based on styrene are produced by reacting the monomer with a regulator by means of free-radical polymerization. At least some of the quantity of regulator is added according to a prescribed program so that at every juncture t the value of the quantitative fraction added up to said juncture does not fall short of the value of the respective conversion U(t) in the polymerization reaction at said juncture t by more than 5 percentage points and does not exceed said value U(t) by more than 5 percentage points.
Abstract:
Composite made of two substrates for use for optical, electronic and/or precision-engineered equipment, comprising a first substrate and a second substrate and, arranged so as to connect the first substrate to the second substrate, an adhesive layer, wherein the adhesive layer comprises an adhesive which has, relative to the mixture, (a) from 60% by weight to 90% by weight of a first polymer component based on polyacrylate and (b) from 10% by weight to 40% by weight of a second polymer component based on elastomers, where the second polymer component is essentially not miscible with the first polymer component, so that the adhesive is present in at least two separate phases in the adhesive layer.
Abstract:
The invention describes a double-sided, carrierless self-adhesive tape which can be used in particular for achieving very durable adhesive bonding of a variety of articles. This double-sided, carrierless self-adhesive tape is composed of a homogeneously crosslinked pressure-sensitive acrylate hotmelt composition of single-layer construction, which may have been lined with release materials such as siliconized release papers or release films. The double-sided, carrierless pressure-sensitive adhesive tape is characterized in that it is composed of a photoinitiator-free, thermally homogeneously crosslinked acrylate hotmelt which is crosslinked predominantly by way of urethane units. It is notable in particular for the fact that it is homogeneously chemically crosslinked through the layer and, in contrast to acrylate layers crosslinked by radiation (UV/EBC), does not exhibit any profile of crosslinking through the layer. It can be used in particular as an adhesive transfer tape for the permanent attachment of articles to a variety of substrates.
Abstract:
The invention provides meltable and UV-crosslinkable pressure-sensitive adhesives, such as acrylate hotmelts or hotmelt formulations, which can be processed by commonplace hotmelt processes and also on customary hotmelt coating lines, without any immediate alteration in the product properties in the event of (unwanted) deviation in the operational parameters. The compositions of the invention are UV-crosslinkable and meltable pressure-sensitive adhesives comprising (i) mixtures of UV-crosslinkable polyacrylate polymers selected from a) mixtures of UV-crosslinkable polymers with at least one photoinitiator bonded covalently to the backbone of the polymers, and b) mixtures of UV-crosslinkable polyacrylate polymers, monomers and at least one photoinitiator, and also (ii) at least one UV stabilizer, and also methods for producing them and the use thereof as bonding agents.
Abstract:
Crosslinked pressure-sensitive adhesives (PSAs) based on polymers of branched macromolecules each comprising a main chain and one or more sidechains pendent to the main chain, the constitutional units thereof originating from a) X wt % of one or more acrylic and/or methacrylic esters, with 80 =1000 g/mol, and the respective amounts of constitutional units originating from a), b) and c) can be the same in each case or differ by not more than 1%, and where a), b) and c) may in each case be the same or different monomers, have detachment properties which can be set independently of one another.
Abstract:
Crosslinker-accelerator system for the thermal crosslinking of polyacrylates with functional groups suitable for entering into linking reactions with cyclic ethers, more particularly epoxide groups or oxetane groups, comprising at least one substance containing epoxide or oxetane groups (crosslinker) and at least one substance with an accelerating action for the linking reaction at a temperature below the melting temperature of the polyacrylate (accelerator).