Ethylene-Free Synthesis of Polyethylene Copolymers and Block Copolymers

Abstract

Herein, we report on a new and innovative post-polymerization modification procedure for the ethylene-free synthesis of polyethylene copolymers and block copolymers. Poly[N-(acryloyloxy)phthalimide] statistical and block copolymers synthesized by straightforward reversible-deactivation radical polymerization are used for thermally and photochemically induced metal-catalyzed decarboxylation yielding polyethylenes by the formation of a secondary radical at the polymer backbone that is able to react with a hydrogen source. The presented route toward various polyethylene structures via decarboxylation reactions establishes a new synthetic method in polymer chemistry, namely, the straightforward and efficient synthesis of different polyethylene block copolymers.

Synthesizing Polyethylene from Polyacrylates: A Decarboxylation Approach

“…15 An alternative to the employment of ethylene gas was already demonstrated by Shea et al using polyhomologation. 12,16 In a similar study to our previous study on decarboxylation of activated ester polymers, 17 the indirect synthesis of polyolefins from an activated ester was demonstrated by Stenzel et al, who used dialkyl zinc reagents to synthesize polyolefins, but not polyethylene, showing the potential of those methods. 18 In a previous study, we could already demonstrate the combination of decarboxylation chemistry in a post-polymerization approach to yield PE copolymers and block copolymers via a new and innovative synthetic method.…”

“…18 In a previous study, we could already demonstrate the combination of decarboxylation chemistry in a post-polymerization approach to yield PE copolymers and block copolymers via a new and innovative synthetic method. 17 Our approach took advantage of the compatibility of well-known activated ester monomers with the RAFT polymerization. 17,19 The utilization of an activated ester combined with an acrylatebased structural motif offers enormous synthetic possibilities.…”

“…17 Our approach took advantage of the compatibility of well-known activated ester monomers with the RAFT polymerization. 17,19 The utilization of an activated ester combined with an acrylatebased structural motif offers enormous synthetic possibilities. 19−21 In this regard, the N-(acryloyloxy)phthalimide structural motif features great synthetic versatility and can be utilized in numerous reactions ranging from aminolysis to photoinduced cross-coupling reactions.…”

Decarboxylation of Poly[N‐(acryloyloxy)phthalimide] as a Versatile Tool for Postpolymerization Modification

“…For the exploration of Michael-type addition experiments homopolymer P1 featuring a molar mass of M n = 6700 g mol −1 and a dispersity of Ð = 1.20 was used (for detailed information see Table S1 in the Supporting Information). Following our previous study of decarboxylation reactions on PAP for the synthesis of PE and PE-block copolymers with a hydrogen-donor, [9,10] we utilize our optimized photochemical decarboxylation method employing Ru(bpy) 3 Cl 2 •6H 2 O as catalyst for the functionalization of PAP.…”

“…In two former studies we used this secondary radical at the backbone in combination with a hydrogen donor for the synthesis of polyethylene homopolymers, copolymers and block copolymers. [9,10] More recently, Sumerlin and co-workers published a similar method to synthesize polyolefins based on a different catalytic system. [11] But the scope of decarboxylation of polymeric materials is by far not only limited to the synthesis of polyolefins.…”