Polymethylmethacrylate bone cement with adjustable initial viscosity, and method for producing a bone cement dough with variable initial viscosity

A method for producing a polymerizable bone cement by mixing two components A and B with each other, wherein

• the component A is present as a powder and comprises
• (a.1) at least one powdered polymethylmethacrylate-co-polymer or a powdered mixture comprising polymethylmethacrylate-co-polymers, wherein the polymethylmethacrylate-co-polymer or powdered mixture comprises at least one particulate polymethylmethacrylate-polymer-co-polymer with a molar mass Mn of more than or equal to 200,000 g/mol to less than or equal to 1,000,000 g/mol, and the at least one polymethylmethacrylate-co-polymer or the powdered mixture is obtained by polymerization of a mixture of more than or equal to 90.0% by weight of methylmethacrylate and from 1% to 10.0% by weight by weight of one or more comonomers selected from the group consisting of at least one alkylacrylate with 1 to 5 C-atoms in the alkyl group, diene, isoprene and a mixture of said comonomers, and the total composition of the at least one polymethylmethacrylate-co-polymer or the powdered mixture accounts for 100% by weight relative to said mixture;
• (a.2) at least one radiopaquer;
• and
• (a.3) at least one polymerization initiator;
• and
• the component B is present as a liquid and comprises
• (b.1) at least one monomer for radical polymerization;
• (b.2) at least one polymerization accelerator;
• and
• (b.3) at least one stabilizer;
• wherein the weight ratio of component A to component B is approximately 2.0:1.0 to 3.4:1.0, and components A and B are mixed at a weight ratio selected from
• a) less than 2.2:1.0,
• b) from 2.2:1.0 to less than 3.3:1.0, or
• c) from more than or equal to 3.3:1.0.

A kit for producing polymerizable bone cements, comprising component A and, optionally, component B, wherein the component A is present as a powder and comprises

• (a.1) at least one powdered polymethylmethacrylate-co-polymer or a powdered mixture of polymethylmethacrylate-co-polymers, wherein the at least one powdered polymethylmethacrylate-co-polymer or the powdered mixture comprises at least one particulate polymethylmethacrylate-polymer-co-polymer with a molar mass Mn of more than or equal to 200,000 g/mol to less than or equal to 1,000,000 g/mol, and the at least one polymethylmethacrylate-co-polymer or the powdered mixture is obtained by polymerization of a mixture of at least 90.0% by weight of methylmethacrylate and from 1% to 10.0% by weight of one or more comonomers selected from the group consisting of at least one alkylacrylate with 1 to 5 C-atoms in the alkyl group, diene, isoprene and a mixture of said comonomers, and the total composition accounts for 100% by weight relative to said mixture;
• (a.2) at least one radiopaquer;
• and
• (a.3) at least one polymerization initiator;
• and
• the optional component B is present as a liquid and comprises (b.1) at least one monomer for radical polymerization;
• (b.2) optionally, at least one polymerization accelerator;
• and
• (b.3i) optionally at least one stabilizer;
• wherein the component A is present in an internal space of a cartridge, wherein the cartridge comprises a cartridge connector with an internal thread on one end and a dispensing plunger on the other opposite end, wherein a mixing rod is attached to or is arranged on a mixing facility on an inside of the cartridge through a feed-through, wherein the mixing facility is operated from outside by moving the mixing rod along an axis of the internal space of the cartridge, and, optionally,
• component B is contained in a disposable monomer container.