Block Copolymers of Polyolefins with Polyacrylates: Analyzing and Improving the Blocking Efficiencies Using MILRad/ATRP Approach

Macromol Rapid Commun. 2024 Apr;45(8):e2300675. doi: 10.1002/marc.202300675. Epub 2024 Jan 9.

Abstract

Despite their industrial ubiquity, polyolefin-polyacrylate block copolymers are challenging to synthesize due to the distinct polymerization pathways necessary for respective blocks. This study utilizes MILRad, metal-organic insertion light-initiated radical polymerization, to synthesize polyolefin-b-poly(methyl acrylate) copolymer by combining palladium-catalyzed insertion-coordination polymerization and atom transfer radical polymerization (ATRP). Brookhart-type Pd complexes used for the living polymerization of olefins are homolytically cleaved by blue-light irradiation, generating polyolefin-based macroradicals, which are trapped with functional nitroxide derivatives forming ATRP macroinitiators. ATRP in the presence of Cu(0), that is, supplemental activators and reducing agents , is used to polymerize methyl acrylate. An increase in the functionalization efficiency of up to 71% is demonstrated in this study by modifying the light source and optimizing the radical trapping condition. Regardless of the radical trapping efficiency, essentially quantitative chain extension of polyolefin-Br macroinitiator with acrylates is consistently demonstrated, indicating successful second block formation.

Keywords: atom transfer radical polymerization; block copolymers; copolymerization; metal–organic insertion light‐initiated radical; polyolefins.

MeSH terms

  • Acrylates / chemistry
  • Acrylic Resins* / chemical synthesis
  • Acrylic Resins* / chemistry
  • Catalysis
  • Light
  • Molecular Structure
  • Palladium / chemistry
  • Polyenes* / chemical synthesis
  • Polyenes* / chemistry
  • Polymerization*
  • Polymers / chemical synthesis
  • Polymers / chemistry

Substances

  • Polyenes
  • PL 732
  • Acrylic Resins
  • Polymers
  • carbopol 940
  • Palladium
  • Acrylates