Triarylphosphine Oxide Containing Nylon 6,6 Copolymers.
Triarylphosphine Oxide Containing Nylon 6,6 Copolymers.
(561 K)
Wan, I. Y.; McGrath, J. E.; Kashiwagi, T.
Chapter 2; ACS Symposium Series 599;
American Chemical Society. Fire and Polymers II:
Materials and Tests for Hazard Prevention. National
Meeting, 208th. ACS Symposium Series 599. August 21-26,
1994, Washington, DC, American Chemical Society,
Washington, DC, Nelson, G. L., Editor(s), 29-40 pp,
1995.
Sponsor:
National Science Foundation, Washington, DC
Keywords:
fire retardants; flame retardants; nylon (trademark);
copolymers; monomers; polymerization; cone calorimeters
Abstract:
A hydrolytically stable triarylphosphine oxide
containing dicarboxylic acid monomer
bis(4-carboxyphenyl) phenyl phosphine oxide
P(O)(Ph)(C6H4COOH)2 was synthesized via Friedel-Crafts
reactions and chemically incorporated into the
poly(hexamethylene adipamide) backbone to produce melt
processible, improved flame resistant copolymers. The
content of triarylphosphine oxide comonomer in the melt
synthesized copolymers was controlled from 0-30 mole%.
The copolymers were crystallizable at 10 and 20 mole%
incorporation of the phosphine oxide comonomer and
produced tough solvent resistant films. The
crystallinity was totally disrupted at 30 mole%, but the
Tg values systematically increased from 58 deg C to 89
deg C. Dynamic TGA results in air at 10 deg C/minute
showed that the char yield increased with phosphine
oxide content. Cone calorimetric tests in a constant
heat environment (40 kW/m2) were employed to investigate
the fundamental flame retardancy behavior of the
copolymers. Significantly depressed heat release rates
were observed for the copolymers containing phosphine
oxide, although carbon monoxide values appeared to
increase. ESCA studies of the char show that the
phosphorus surface concentration was significantly
increased relative to copolymer composition. It was
concluded that the triaryl phosphine oxide containing
nylon 6,6 copolymers had improved flame resistance and
that tough melt processible films and fibers could be
produced from these modified copolyamides.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899