Hammett Relations in Anionic Polymerization. Reaction of Polystyrylakali Salts with Disubstituted 1,1-Diphenylethylenes

Monomer sequence determination in the living anionic copolymerization of styrene and asymmetric bi-functionalized 1,1-diphenylethylene derivatives

“…40,41 That is, k can be adjusted by varying the type (electron withdrawing or donating) and quantity of functional groups as well as the substituted positions on the phenyl rings of DPE. 42 Therefore, the copolymerization system of styrene and DPE derivatives can easily synthesize polymers with strictly controlled sequences and arrangements. In addition, the design of DPE is the first and most important step in polymeric sequence control.…”

“…The advantage of this method is that the sequence structure of binary copolymers synthesized from bi-functionalized DPE derivatives is controlled more easily and distinctly than that of the ternary copolymers synthesized from monofunctionalized DPE derivatives. Furthermore, DPE derivatives with precisely designed reactivity ratios can be obtained 42 by varying the types of functional substituents and their position on benzyl rings using the Hammett equation. 47 Two types of asymmetric bi-functionalized DPE derivatives, DPE-SiH/OMe and DPE-SiH/NMe 2 , were designed and synthesized.…”

Anionic synthesis of aromatic amide and carboxyl functionalized polymers. Chain-end functionalization of poly(styryl)lithium withN,N-diisopropyl-4-(1-phenylethenyl)benzamide

“…Recently, a general synthetic route for the preparation of well-defined funcytio-N,N-diisopropylamide group as protecting group and reported the quantitative synthesis of polynalized polymers was developed, which involves the reactions of simple and polymeric organo-[N,N-diisopropyl-4-vinylbenzamide) by the oligo(a-methylstyryl)lithium-initiated polymerizalithium compounds with 1,1-diphenylethylene 12 and substituted 1,1-diphenylethylenes with polar tion of N,N-diisopropyl-4-vinylbenzamide in THF at 078ЊC. Herein, we report the chain-end funcgroups 13 as well as protected protic substituents such as the phenolic hydroxyl group 14,15 and the tionalization reaction poly(styryl)lithium with N,N-diisopropyl-4-(1-phenylethenyl)benzamide primary amine group.…”

Sequence Determination and Regulation in the Living Anionic Copolymerization of Styrene and 1,1‐Diphenylethylene (DPE) Derivatives

“…The substituent –SiH group exhibited a weak electron‐withdrawing property (σ = +0.04), while the sequence was determined as a DPE‐SiH unit gradient decreasing along the chain. As we know, the substituent groups in the DPE structure showed remarkable effect on the corresponding living anionic copolymerization . Therefore, we changed the substituent groups of DPE derivatives and especially introduced different electron‐donating groups to adjust the copolymerization and investigate the corresponding variations in the sequence structure.…”