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In recent years, fire accidents occurred frequently, reportedly, of those deaths due to fire accident in the world, more than 90% because of the burning of polymer materials emit smoke and toxic gas makes suffocate, therefore, developed without toxic pollution-free flame retardant polymer materials has become an important topic in today's scientific development. Polyvinyl alcohol (PVA) is an excellent, a wide range of uses of the polyhydroxy polymer. Into the fiber resistance and adhesion, etc., and having good mechanical properties, due to the polyvinyl alcohol has a good compatibility, film formability, having a wide range of uses in fibers, films, adhesives, and biomedical materials field . In this article, synergies through the study of several flame retardants on flame retardant properties of PVA prepared retardant properties of PVA composite fibers. Combustion of the phosphorus-based flame retardant in the surface of the material to generate carbon layer through the barrier to achieve the purpose of flame retardancy to the contact of the material with the fire source; nonflammable gas such as nitrogen, water vapor is generated in the combustion of a nitrogen-based flame retardant, reducing combustion environment oxygen concentration, which has a flame-retardant properties; inorganic flame retardant combustion process absorbs heat, and the release of water vapor and other gases, can achieve the effect of the flame retardant and smoke suppression. In this issue, were used the United Artists phosphorus flame retardant FR-106 melamine MA, LDH three kinds of nano-hydrotalcite flame retardant different proportions of mixed research synergy flame retardant properties of PVA. (1) phosphorus-based flame retardant (FR) may be added to improve flame retardant properties, when the FR added amount reached 20%, the one component of the flame-retardant effect of the PVA film. Proved, this is due to FR added amount exceeds 20%, FR the phenomenon of phase separation, thus affecting the flame retardant properties of the composite film will be generated in the PVA solution. (2) Phosphorus-based flame retardant (FR) and an inorganic flame retardants (LDH) in the PVA solution can achieve a synergistic flame retardant effect when both the proportion of 40% of the PVA content: 8%, the flame retardant effect Jia. This is due to the LDH in water-insoluble FR exist conditions can be well dispersed in the PVA solution, it can be better play their synergistic flame retardant. (3) a nitrogen-based flame retardant (MA) one-component added to the PVA solution, and does not significantly improve the flame retardant properties of the PVA composite film, LDH deposition continue to add to this solution, the film does not have good barrier burning effect. This is due to the MA and LDH are not well dissolved in the PVA solution, the phenomenon of agglomeration occurs in solution, resulting in the flame retarding effect of the two not play. (4) a phosphorus-based flame retardant (FR) with the nitrogen-based flame retardant (MA) between the two can be formed a good synergistic effect when FR: MA = 20%: 20%, the composite film flame retardant properties , mechanical properties, thermal properties to achieve the best two flame retardants in this ratio under the maximum extent possible to create synergies. Added to the composite solution LDH, When the LDH dosage 8%, the the composite film retardant best performance, LOI values ??up to 31. (5) in accordance with the best ratio FR: MA: LDH = 205:20%: 8% Preparation of PVA spinning solution, spinning solution and spinning process are discussed, the results showed that: FR / MA / LDH / PVA spinning the silk dope presents typical shear-thinning phenomenon. Prepared by wet spinning flame retardant modified PVA fibers, studies have shown that the the modified fiber better performance by limiting oxygen index test, the composite fiber LOI value of 28.
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