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Flammability Studies of Polymer Layered Silicate Nanocomposites: Polyolefin, Epoxy, and Vinyl Ester Resins.


pdf icon Flammability Studies of Polymer Layered Silicate Nanocomposites: Polyolefin, Epoxy, and Vinyl Ester Resins. (1228 K)
Gilman, J. W.; Kashiwagi, T.; Nyden, M. R.; Brown, J. E. T.; Jackson, C. L.; Lomakin, S. M.; Giannelis, E. P.; Manias, E.

Chemistry and Technology of Polymer Additives. Chapter 14. 1999, Blackwell Science Inc., Malden, MA, Ak-Malaika, S.; Golovoy, A.; Wilkie, C. A., Editor(s)(s), 249-265 pp, 1999.

Keywords:

nanocomposites; polyolefins; epoxy resins; vinyl resins; flammability; fire retardants; cone calorimeters; heat release rate; char formation; thermal analysis

Abstract:

In the pursuit of improved approaches to fire retarding polymers a wide variety of concerns must be addressed, in addition to the flammability issues. For commodity polymers the low cost of these materials requires that the fire retardant (FR) approach also be of low cost. This limits solutions to the problem primarily to additive type approaches. These additives must be low cost and easily processed with the polymer. In addition, any additive must not excessively degrade the other performance properties of the polymer, and it must not create environmental problems in terms of recycling or disposal of the final product. Polymer layered silicate (PLS) nanocomposites are materials that may fulfil the above requirements for a high performance flame retardant. PLS nanocomposites are hybrid organic polymer-inorganic materials with unique properties when compared with conventional filled polymers. For example, the mechanical properties of a nylon-6 layered-silicate nanocomposite, with a silicate mass fraction of only 5%, show excellent improvement over those for the pure nylon 6. The nanocomposite exhibits a 40% higher tensile strength, 68% greater tensile modulus, 60% higher flexural strength, and a 126% increased flexural modulus. The heat distortion temperature (HDT) is increased from 65C to 152C. In some cases, increased thermal stability, an important property for improving flammability performance, as well as decreased gas permeability, and increased solvent resistance accompany the improved physical properties. We have reported on the flammability properties of delaminated nylon 6 layered silicate nanocomposites and intercalated polymer layered-silicate nanocomposites prepared from polystyrene (PS) and polypropylene-graft-maleic anhydride (PP-g-MA). Here, we will briefly review these results and report on our initial studies of the flammability of thermoset PLS nanocomposites: intercalated vinyl ester silicate and intercalated epoxy silicate nanocomposites.