Flame retardency testing

There are many flame retardant tests used with some frequency for nonwovens. 

The second substrate utilized was a high loft polyester, representative of material used in air filters, furniture padding, and automobile interior pads. The material used here is constructed of 1 1/2 denier fiber, weighs 1 1/2 ounces per square yard, and is relatively open in construction. Polyester as a material is water resistant and flammable. This fiber ignites at around 520°C, but melts at about 265°C. In many flame retardant tests, the polyester will melt and shrink" away from the flame, giving spurrious results. Once again, not all binders have an affinity for this substrate, and flame retardancy is affected. 

EVCL s are compatible with all flame retardants tested, and perform well with all but one. 

Another experimental program was conducted with binder-flame retardant combinations on rando-rayon. The eighteen flame retardants were paired with a latex binder and screened for performance in an NFPA-701 flame retardant test. Seven of the best performing flame retardants were chosen for further study. Additionally, since all seven happened to be non-durable, the best performing durable flame retardant was added at a higher add-on and flame retardant level. 

The performance of several latex binders in flame retardant testing of nonwoven polyester or rayon substrates with and without added flame retardants has been investigated. Correlation of coating flammability (i.e. by oxygen index) to actual performance on a substrate is poor. Results generated on both rayon and polyester... 

Since combustion is subject to many variables, tests for flame retardancy may not correctly predict flame resistance under unusual conditions. Thus, a disclaimer stating that flame retardancy tests do not predict performance in an actual fire must accompany all flame-retardant products. Flame retardants, like many organic compounds, may be toxic or may produce toxic gases when burned. Hence, care must be exercised when using fabrics or other polymers treated with flame retardants. 

Morgan, A.B., Jurs, J.L., and Tour, J.M. 2000. Synthesis, flame retardancy testing, and preliminary mechanism studies of nonhalogenated aromatic boronic acids. J. Appl. Polym. Sci. 76, 1257. 

Selected diblock polymers are provided in Table 1. Izod impact strength and flame retardancy testing are provided in Table 2. Flame retardancy was measured according to the UL-94 standard. 

Note Flame retardancy testing was measured according to the UL-94 standard. 

For all methods, strict adherence to the testing protocol is crucial to obtaining reliable and repeatable resnlts. However, it is important to recognise that if a fabric passes a particular test, it j ust means that the fabric passed this particnlar test. There are no other performance guarantees. More detailed information on actual flame retardancy test methods and an outlook on their development have been published. ... 

It is the actual geometry of a final product in combination with the energy input of the flame retardant test or fire that determines what the degree of flame retardancy will be. The laws of mass and heat transport dictate that when the geometry changes, mass and heat transfer will change in a strong non-linear way. As a consequence, actual fire behaviour can be vastly different on end products compared to FR tests on small-scale test specimens of the materials out of which these products are made. 

An invention which provided an additive for polyethylene that produced polyethylene with self-extinguishing properties xmder an ASTM flammability test and flame-retarding properties according to an Underwriters Laboratories flame retardant test, was disclosed in U.S. Patent 2,480,298 issued to WB. Happoldt on August 30, 1948, and assigned to DuPont Company. The combination of antimony trioxide (20-35 wt%), at least... 

ATH and MH are used primarily in wire and cables in poly( vinyl chloride) (PVC), polyethylene, and various elastomers. There is also some limited application of MH in polyamide-6. To pass flame retardancy tests, 35 to 65 wt% of metal hydroxide is required. Decreasing the loading of metal hydroxides will result in a significant gain in physical properties, especially low-temperature flexibility therefore, combinations with red phosphorus, sUicones, boron compounds, nanoclays (treated montmorillonites), and charring agents have been explored. Surface treatment of metal hydroxides also helps to improve physical properties and sometimes improves flame retardancy, due to better dispersion. 

TABLE 6 Standardized methods for flame retardant testing... 

Flame retardancy tests were performed following the procedure of Underwriter s Laboratory Bulletin 94 entitled Tests for Flammability of Plastic Materials, UL94. According to this procedure, materials may be classified as HB, VO, VI, V2, VA and/or VB on the basis of the test results obtained for five samples. In this study, UL test was done at 0.8 mm thickness for all samples. Heat deflection Temperature (HDT, ISO 75/Be flat, 1.8 Mpa load) and Vicat softening temperature (Vicat, ISO 306, Vicat B, heating rate 120 °C/min load of 50 N) were used to determine thermal properties of compositions. Standard impact bars were used to measure these properties. Duplicate measurements were done and average of two samples were reported. 

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