US 12,252,661 B2
Process for preparing homo- and copolymers of alkyl (meth)acrylates with low residual monomer content
Frank-Olaf Mähling, Mannheim (DE); Maria Stimeier, Darmstadt (DE); Thomas Schimmel, Shanghai (CN); Stefan Karl Maier, Ober-Ramstadt (DE); and Sofia Sirak, Plymouth Meeting, PA (US)
Assigned to Evonik Operations GmbH, Essen (DE)
Appl. No. 18/257,675
Filed by Evonik Operations GmbH, Essen (DE)
PCT Filed Dec. 17, 2021, PCT No. PCT/EP2021/086447
§ 371(c)(1), (2) Date Jun. 15, 2023,
PCT Pub. No. WO2022/129495, PCT Pub. Date Jun. 23, 2022.
Claims priority of application No. 20215325 (EP), filed on Dec. 18, 2020.
Prior Publication US 2024/0043768 A1, Feb. 8, 2024
Int. Cl. C10M 145/14 (2006.01); C08F 293/00 (2006.01); C10M 169/04 (2006.01); C10N 20/00 (2006.01)
CPC C10M 145/14 (2013.01) [C08F 293/005 (2013.01); C10M 169/041 (2013.01); C10M 2203/003 (2013.01); C10M 2209/084 (2013.01); C10N 2020/071 (2020.05)] 20 Claims
OG exemplary drawing
 
1. A method for preparing a polyalkyl (meth)acrylate, the method comprising:
(i) preparing a reaction mixture comprising:
(A) at least two different alkyl (meth)acrylates;
(B) optionally, a chain transfer agent; and
(C) optionally, a base oil,
(ii) charging the reaction mixture prepared under (i) to a reaction vessel;
(iii) heating the reaction mixture to a desired reaction temperature;
(iv) adding 0.1 wt. % to 4 wt. %, based on a total amount of monomers used, of a free radical initiator 1, either continuously or stepwise;
(v) adding, after a monomer conversion of at least 95% was achieved, 0.05 wt. % to 0.2 wt. %, based on the total amount of monomers used, of an initiator 2, and less than 1 wt. %, based on the total amount of monomers used, of an additional monomer selected from the group consisting of C4-14 alkyl acrylates, C4-14 alkyl methacrylates, C4-14 alkyl maleates, C4-14 alkyl fumarates, and styrene, to the reaction mixture; and
(vi) optionally, further processing of the reaction mixture to receive the targeted polyalkyl (meth)acrylate,
wherein the monomer conversion is determined by measuring a residual monomer content by high performance liquid chromatography (HPLC) method.