High temperature reactions of an aryl-alkyl phosphine, an exceptionally efficient melt stabiliser for polyethylene

Gábor Pénzes, Attila Domján, Dóra Tátraaljai, Peter Staniek, Enikod́ Földes, Béla Pukánszky

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Bis(diphenylphosphino)-2,2-dimethylpropane (PMP) is a highly efficient melt stabiliser of polyethylene. This aryl-alkyl phosphine hinders the degradation of the polymer during processing even in small concentrations and in combination with a phenolic antioxidant its consumption rate is considerably slower than that of phosphites and phosphonites. In this study the reactions of PMP were studied at temperatures corresponding to those used for the processing of polyethylene in order to explore the processing stabilisation mechanism of this additive. Thermal and thermo-oxidative stability were determined by DSC and TGA, respectively by heating PMP in argon and oxygen at 200 and 240 °C. Reactions with peroxy, carbon-centred and oxy radicals, as well as with hydroperoxide were investigated at 200 °C. Reaction products were identified by FT-IR and solution-state NMR spectroscopy. The results revealed that the phosphine studied has sufficient thermal- and thermo-oxidative stability under the processing conditions of polyethylene. It oxidises easily with any oxidising agent including molecular oxygen of air. Consequently, PMP does not only decompose hydroperoxide groups and react with oxy macroradicals during the processing of polyethylene, as claimed by most references on phosphorous antioxidants, but it can also hinder the formation of peroxy macroradicals, i.e., the initiation reaction of thermo-oxidative degradation.

Original languageEnglish
Pages (from-to)1627-1635
Number of pages9
JournalPolymer Degradation and Stability
Volume95
Issue number9
DOIs
Publication statusPublished - Sep 1 2010

    Fingerprint

Keywords

  • Aryl-alkyl phosphine
  • Heat-stability
  • High temperature reactions
  • NMR
  • Oxidation
  • Stabilising mechanism

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Mechanics of Materials
  • Polymers and Plastics
  • Materials Chemistry

Cite this