Anionic polymerization of alkyl methacrylates and molecular weight distributions of the resulting polymers

Anionic polymerization of alkyl methacrylates using flow microreactor systems

“…even at temperatures higher than 0 • C. n-Butyl methacrylate underwent the polymerization in a highly controlled manner even at 0 • C to give the polymers of narrow molecular-weight distribution. tert-Butyl methacrylate also underwent the polymerization at the same controlled manner to give the polymers of narrow molecularweight distribution even at 24 • C. Presumably the bulkiness of the alkyl group seems to suppress side reactions such as the attack of propagating enolate on the carbonyl group [58]. These results indicate that flow microreactor systems open a new possibility of living anionic polymerization of alkyl methacrylates.…”

Anionic polymerization of alkyl methacrylates in the presence of diethylzinc

“…These peaks can be attributed to the base PMMA, the propagating end of which is deactivated before the addition of TBMA. Based on the molecular weight and the relative peak area of the GPC, the amounts of the deactivated PMMA at -78 "C for 1, 30 (4,35) TBMA (6,ll) MMA (4,56) TBMA (7,92) MMA (3,48) TBMA (8,35) MMA (2,85) TBMA (4,73) MMA (5,64) IPMA (5,06) TBMA (5,38) IPMA (4,07) IPMA (5,15) TBMA (5,21) TBMA (4,70) 19,20, and 21), respectively. Quirk mentioned that GPC measurement was useful to estimate the amount of deactivated base polymer contaminated in the block or post polymer through the sequential polymerization and that the limitation of accuracy was inevitable 5).…”

Synthesis of Arborescent Copolymers by a One‐Pot Method

“…Two major side reactions are known in the polymerization of these monomers: carbonyl group attack and α ‐proton abstraction (for the acrylates), particularly during the initiation step 23, 24. Bulky alkyl substituents such as the tert ‐butyl group can help prevent attack of the carbonyl moiety 25. Highly hindered modifiers like 1,1‐diphenylethylene25, 26 are widely used to reduce the reactivity of initiators including butyllithium and polystyryllithium.…”

“…Bulky alkyl substituents such as the tert ‐butyl group can help prevent attack of the carbonyl moiety 25. Highly hindered modifiers like 1,1‐diphenylethylene25, 26 are widely used to reduce the reactivity of initiators including butyllithium and polystyryllithium. In the system under investigation, the initiating centers obtained by activation of the isopropenyl moieties are sterically hindered, and similar in structure to poly( α ‐methylstyryl) anions.…”