Semiinterpenetrating polymer network latexes via concentrated emulsion polymerization

✍ Scribed by Eli Ruckenstein; Hangquan Li

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 842 KB
• Volume: 55
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1995.070550614

✦ Synopsis

Latexes of semiinterpenetrating polymer networks (SIPN) of polyurethane (PU) and poly(methy1 methacrylate) (PMMA) were prepared via the concentrated emulsion polymerization. In this procedure, a partially cross-linked PU was first prepared in a low polarity solvent from the appropriate precursors. Subsequently, MMA and an initiator were introduced into the solution, and the solution was used as the dispersed phase of a concentrated emulsion in water. Finally, SIPN latexes were obtained via the polymerization of the concentrated emulsion. For comparison purposes, SIPN materials have been also prepared via bulk polymerization. The studies with differential scanning calorimetry and transmission electronic microscopy showed that partial interpenetration was achieved in the SIPN latexes. The tensile behavior and particle morphology of the SIPN materials were investigated by changing the proportion of PU, the molar ratio of NCO/OH, the theoretical cross-link density, and the concentration of the initiator. The SIPN latexes prepared possess a high toughness.