Dimensionally stable adhesive and its use for glue sticks
A dimensionally stable adhesive can be applied at room or ambient temperature to substrate surfaces. It comprises at least one, or two or more, polyfin(s) prepared in the presence of metallocene catalyst and having a ring & ball softening point in the range from 50 to 165° C., a needle penetration number of <50×0.1 mm, and a melt viscosity, measured at a temperature of 170° C., in the range from 20 to 40 000 mPa·s. The adhesive is water- and solvent-free and is used as a glue stick in the form of sticks, blocks, figures, spheres or cones.
1 . A dimensionally stable adhesive which can be applied at room or ambient temperature to a surface of a substrate, comprising at least one polyolefin prepared in the presence of a metallocene catalyst, wherein the at least one polyolefin has a ring & ball softening point in the range from 50 to 165° C., a needle penetration number of <50×0.1 mm, and a melt viscosity, measured at a temperature of 170° C., in the range from 20 to 40 000 mPa·s.
2 . The dimensionally stable adhesive as claimed in claim 1 , wherein the adhesive is water- and solvent-free.
3 . The dimensionally stable adhesive as claimed in claim 1 , wherein the at least one polyolefin has a drop point or ring & ball softening point in the range from 60 to 165° C.
4 . The dimensionally stable adhesive as claimed in claim 1 , wherein the at least one polyolefin has a number-average molar mass M n in the range from 500 to 20 000 g/mol, and a weight-average molar mass M w in the range from 1000 to 40 000 g/mol.
5 . The dimensionally stable adhesive as claimed in claim 1 , wherein the at least one polyolefin is a homopolymer of linear or branched 1-olefins having 3 to 20 carbon atoms or are olefin copolymers comprising linear or branched 1-olefins having 3 to 20 carbon atoms and, optionally, ethylene.
6 . The dimensionally stable adhesive as claimed in claim 1 , wherein the wherein the at least one polyolefin is a propylene homopolymer or copolymer of propylene with one or more further monomers selected from the group consisting of ethylene and linear or branched 1-olefins having 4 to 20 carbon atoms, the amount of structural units originating from polypropylene in the case of the copolymers being between 70% and 99.9%.
7 . The dimensionally stable adhesive as claimed in claim 1 , further comprising one or more polar-modified olefin homopolymers, copolymers or a mixture thereof.
8 . The dimensionally stable adhesive as claimed in claim 1 , wherein the amount of the at least one polyolefin is in the range from 2% to 100% by weight.
9 . The dimensionally stable adhesive as claimed in claim 1 , further comprising one or more resins in an amount in the range from 0% to 60%.
10 . The dimensionally stable adhesive as claimed in one claim 1 , further comprising one or more plasticizers.
11 . The dimensionally stable adhesive as claimed in claim 1 , further comprising an additional, a polar or polar, polyolefin, wax, colorant, filler, stabilizer, antioxidant or a mixture thereof.
12 . A glue product comprising the dimensionally stable adhesive as claimed in claim 1 .
13 . The dimensionally stable adhesive as claimed in claim 1 , wherein the melt viscosity, measured at a temperature of 170° C., of the at least one polyolefin is from 50 to 30 000 mPa·s.
14 . The dimensionally stable adhesive as claimed in claim 1 , wherein the melt viscosity, measured at a temperature of 170° C., of the at least one polyolefin is from 10 to 20 000 mPa·s.
15 . The dimensionally stable adhesive as claimed in claim 1 , wherein the at least one polyolefin has a drop point or ring & ball softening point in the range from 70 to 150° C.
16 . The dimensionally stable adhesive as claimed in claim 1 , wherein the at least one polyolefin has a drop point or ring & ball softening point in the range from 80 to 140° C.
17 . The dimensionally stable adhesive as claimed in claim 1 , wherein the at least one polyolefin has a number-average molar mass M n in the range from 800 to 10 000 g/mol, and a weight-average molar mass M w in the range from 1600 to 30 000 g/mol.
18 . The dimensionally stable adhesive as claimed in claim 6 , wherein the the amount of structural units originating from polypropylene in the case of copolymers being between 80% and 99% by weight.
19 . The dimensionally stable adhesive as claimed in claim 1 , wherein the amount of the at least one polyolefin is in the range from 30% to 90% by weight.
20 . The dimensionally stable adhesive as claimed in claim 1 , wherein the amount of the at least one polyolefin is in the range from 40% to 70% by weight.
21 . The dimensionally stable adhesive as claimed in claim 1 , wherein the amount of the at least one polyolefin is in the range from 50% to 60% by weight.
22 . The dimensionally stable adhesive as claimed in claim 1 , further comprising one or more resins in an amount in the range from from 10% to 50% by weight.
23 . The dimensionally stable adhesive as claimed in claim 1 , further comprising one or more resins in an amount in the range from 20% to 40% by weight.
24 . The glue product as claimed in claim 12 , wherein the glue product is in the form of a stick, block, figure, sphere or cone.