Anionic graft copolymerization of methyl methacrylate with lithium diisopropylamide‐treated poly(methacrylate)s

Abstract

AbstractThe anionic grafting of methyl methacrylate onto several lithium diisopropylamide (LDA)‐treated polymers of methacrylates, such as 2‐acetoxyethyl methacrylate (1), 2‐propionyloxyethyl methacrylate (2), 2‐isobutyryloxyethyl methacrylate (3), 1‐methoxy‐carbonylethyl methacrylate (4), and methoxycarbonylmethyl methacrylate (5), or onto the LDA‐treated copolymers of the methacrylates with styrene was investigated. Graftings onto homopolymethacrylates and onto the copolymers of 1 and 2 with styrene did not occur due to the deactivation of the macromolecular lithium enolate by side reactions. Graftings onto copolymers P‐3, P‐4 and P‐5, from methacrylates 3, 4 and 5 with styrene, however, proceeded. The relative grafting efficiency decreases in the following order: P‐3 > P‐4 > P‐5. The grafting is highly influenced by the aggregation behavior of the macromolecular lithium enolates and the side reactions deactivating the lithium enolate. The aggregation behavior decreases the number of the activated points on the feed polymer, lowers the inititiation rate and the polymerization rate of the grafting, and causes a large polydispersity value (M̄w/M̄n) of the side‐chain poly(MMA).