Approaches to phthalimido and amino end-functional polystyrene by atom transfer radical polymerisation (ATRP)

Almar Postma, Thomas P. Davis, Graeme Moad, Michael S. O'Shea

Research output: Contribution to journalArticleResearchpeer-review

31 Citations (Scopus)

Abstract

Approaches to the synthesis of amine end-functional polystyrenes through intermediary phthalimido end-functional polystyrenes have been explored. Phthalimido groups can be quantitatively converted to amine groups by hydrazinolysis according to an Ing-Manske procedure. Approaches based on α- (functional initiator) and ω-functionalisation (end-group substitution) were examined. Thus, well defined, low molecular weight, ω-bromopolystyrenes, prepared by atom transfer radical polymerisation (ATRP) with copper(I) bromide, 4,4′-di-(nonyl)-2,2′ bipyridine (dNbpy) and 1-bromoethylbenzene initiator, were transformed into ω-phthalimidopolystyrenes by substitution with potassium phthalimide. However, elimination of the terminal bromine to form an unsaturated chain end was observed as a side reaction. Various α-phthalimidopolystyrenes were successfully prepared using phthalimido-functional initiators. Phthalimido-functional bromo isobutyrate derivatives proved very effective in yielding very low polydispersity polystyrene (Mw/Mn ∼ 1.1). However, the conversion of the derived α-phthalimidopolystyrense to an α-aminopolystyrene was problematic because of concomitant hydrazinolysis of the isobutyrate ester linkage and other side reactions. N-(Bromomethyl)phthalimide was successfully used as an ATRP initiator to prepare low polydispersity α-pthalimidopolystyrene (Mw/Mn ∼ 1.3) and thence α-aminopolystyrene with a high degree of end-group purity. End-group interconversions were followed by 1H NMR.

Original languageEnglish
Pages (from-to)137-147
Number of pages11
JournalReactive and Functional Polymers
Volume66
Issue number1
DOIs
Publication statusPublished - 1 Jan 2006
Externally publishedYes

Keywords

  • α- and ω-end-functional
  • Amine
  • Atom transfer radical polymerisation (ATRP)
  • Phthalimido
  • Polystyrene

Cite this