New Phosphonated Methacrylates: Synthesis, Photocuring and Study of their Thermal and Flame-Retardant Properties

✍ Scribed by Boulos Youssef; Laurence Lecamp; Wassef El Khatib; Claude Bunel; Bruno Mortaigne

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 154 KB
• Volume: 204
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200300025

✦ Synopsis

Abstract

In this work, a new methacrylate phosphonate monomer synthesis was described according to two routes: firstly, by condensation of methacrylic acid with a phosphonate epoxide and secondly by an esterification between methacryloyl chloride and a phosphonate diol. The photoinduced polymerization of this new monomer was studied as a function of reaction temperature. The optimal conversion of the photopolymerization was 81% for temperatures below 60 °C. Above 60 °C, the existence of a thermal polymerization leads to a decrease in the apparent photochemical yield. This new monomer is less reactive than the commercial dimethacrylate polyether of Bisphenol A we have used for copolymerization. Mechanical and thermal properties of the final copolymers were studied as a function of methacrylate phosphonate monomer content. T~g~ of the copolymers reaches a maximum when the phosphorus content is about 2%. The addition of phosphorus leads to an improvement of the thermal and flame‐retardant properties. Thus, addition of 2% phosphorus allows us to decrease the degradation rate, to increase the amount of remaining residue after combustion up to 12%, and finally to increase the Limiting Oxygen Index (LOI) from 16.8 (0% P) to 21.4 (2% P).

Synthetic routes to methacrylate phosphonated monomer.

magnified imageSynthetic routes to methacrylate phosphonated monomer.