Thermoset Epoxy–Clay Nanocomposites: The Dual Role of α,ω-Diamines as Clay Surface Modifiers and Polymer Curing Agents
✍ Scribed by Costas S. Triantafillidis; Peter C. LeBaron; Thomas J. Pinnavaia
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 343 KB
- Volume
- 167
- Category
- Article
- ISSN
- 0022-4596
No coin nor oath required. For personal study only.
✦ Synopsis
IN HONOR OF PROFESSOR GALEN STUCKY ON THE OCCASION OF HIS 65TH BIRTHDAY
Diprotonated forms of polyoxypropylene diamines of the type , -[NH 3 CHCH 3 CH 2 (OCH 2 CHCH 3 ) x NH 3 ] 2 > with x"2.6, 5.6, and 33.1, have been intercalated into montmorillonite and 6uorohectorite clays and subsequently evaluated for the formation of glassy epoxy}clay nanocomposites. The intercalated onium ions functioned concomitantly as a clay surface modi5er, intragallery polymerization catalyst, and curing agent. Depending on the chain length of the diamine, di4erent orientations of the propylene oxide chains were adopted in the clay galleries, resulting in basal spacings from &14 A s (lateral monolayer, x"2.6) to &45 A s (folded structure, x"33.1). The initial clay basal spacings were correlated with the formation of intercalated and exfoliated clay}epoxy nanocomposites with improved mechanical properties and high thermal stabilities. In comparison to clay}monoamine intercalates, the use of diamine intercalates greatly reduced the plasticizing e4ect of the alkyl chains on the polymer matrix, resulting in improved mechanical properties while at the same time reducing the cost and time needed for nanocomposite fabrication.
2002 Elsevier Science (USA)