US 12,187,867 B2
PMMA-based cast polymers having improved mechanical properties
Thomas Richter, Darmstadt (DE); Christoph Seipel, Babenhausen (DE); and Kay Bernhard, Darmstadt (DE)
Assigned to Evonik Operations GmbH, Essen (DE)
Appl. No. 17/632,983
Filed by Evonik Operations GmbH, Essen (DE)
PCT Filed Jul. 3, 2020, PCT No. PCT/EP2020/068757
§ 371(c)(1), (2) Date Feb. 4, 2022,
PCT Pub. No. WO2021/023444, PCT Pub. Date Feb. 11, 2021.
Claims priority of application No. 19190732 (EP), filed on Aug. 8, 2019.
Prior Publication US 2022/0275160 A1, Sep. 1, 2022
Int. Cl. C08J 9/06 (2006.01); C08J 9/00 (2006.01); C08J 9/02 (2006.01); C08J 9/10 (2006.01); C08K 13/02 (2006.01)
CPC C08J 9/02 (2013.01) [C08J 9/008 (2013.01); C08J 9/06 (2013.01); C08J 9/10 (2013.01); C08K 13/02 (2013.01); C08J 2203/04 (2013.01); C08J 2333/12 (2013.01)] 16 Claims
 
1. A composition for producing a poly(methyl methacrylate)-based (PMMA-based) cast polymer, wherein the composition contains:
1% to 10% by weight of urea and/or a urea derivative,
0.001% to 2.0% by weight of an initiator,
0% to 20% by weight of a further non-polymerizable blowing agent,
0% to 5% by weight of a chain-transfer agent,
0.5% to 10% by weight of a hydrophilic inorganic compound essentially not soluble in the composition, and
53% to 98.498% by weight of a monomer mixture consisting of
60% to 95% by weight of methyl methacrylate (MMA),
5% to 40% by weight of acrylic acid, methacrylic acid, and/or itaconic acid,
and 0% to 35% by weight of a further MMA-copolymerizable monomer other than urea derivatives,
wherein the hydrophilic inorganic compound has a methanol wettability of less than 30% by volume of methanol in a methanol/water mixture,
the monomer mixture contains essentially no styrene, α-methylstyrene, and/or chlorostyrene and excludes methacrylamide, N-alkyl(meth)acrylamides and N,N-dialkylmethacrylamides, and
the hydrophilic inorganic compound is selected from the group consisting of silica, a metal oxide, a metal hydroxide, a metal silicate, talcum, and a mixture thereof,
wherein a PMMA-based cast polymer produced from the composition has an elastic modulus of at least 4,500 MPa, measured at room temperature.