Mechanism of Action of Phosphorus-Based Flame Retardants in Nylon 6. II. Ammonium Polyphosphate/Talc

1995 ◽  
Vol 13 (1) ◽  
pp. 43-58 ◽  
Author(s):  
S.V. Levchik ◽  
G.F. Levchik ◽  
G. Camino ◽  
L. Costa

Talc added to PA-6 fire retardant with APP increases the oxygen index and upgrades the UL94 ranking to class V0. A chemical reaction of APP with talc, detected in the mixtures above 350°C, prevents volatilization of poly phosphoric acid and increases the amount of thermally stable solid residue. The inorganic phosphates that are formed improve the insulating properties of the intumescent layer on the surface of burning PA-6, as compared to the use of APP alone.

2020 ◽  
pp. 28-30
Author(s):  
I. U. Zolkina ◽  
S. A. Radzinsky ◽  
T. I. Andreeva ◽  
D. Kh. Safin ◽  
A. V. Presnyakov ◽  
...  

A brief review of the results of research on reducing the flammability of modified materials based on polycarbonate, the effect of flame retardants and additives that reduce dropping, as well as affecting the complex of properties of polycarbonate is presented. The optimal concentrations of modifying additives for obtaining fire-resistant compositions with high optical characteristics have been determined. It is shown that to achieve the maximum flammability category (PV-0 at a thickness of 2 mm) and oxygen index (42.3%) for thin-walled products, it is necessary to use a high- viscosity grade of polycarbonate (MFI 2.5±1.0 g/10 min), alkali metal sulfonates as a fire retardant and an anti-dripping additive.


1995 ◽  
Vol 19 (1) ◽  
pp. 1-10 ◽  
Author(s):  
S. V. Levchik ◽  
G. Camino ◽  
L. Costa ◽  
G. F. Levchik

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 435
Author(s):  
Feiyu Tian ◽  
Deliang Xu ◽  
Xinwu Xu

This study explored the feasibility of fabricating fire-retardant strandboard with low mechanical properties deterioration to the physico-mechanical properties. A hybrid fire-retardant system of ammonium polyphosphate (APP) and 1,3,5-tris(2,3-dibromopropyl)-1,3,5-triazinane-2,4,6-trione (TBC) was investigated. Thermogravimetric analysis results show that both APP and TBC enhance the thermal stability and incombustibility of wood strands. An infrared spectrum was applied to investigate the effect of flame retardants on the curing behaviors of polymeric diphenylmethane diisocyanate (PMDI) resin. Based on the results of limiting oxygen index (LOI) and Cone calorimetry (CONE), APP and TBC both lead to a higher fire retardancy to strandboard. It is worth mentioning that the two flame retardants lead to evidently differential influences on the modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB), and water-soaking thickness swelling (TS) properties of strandboard. Hence, a hybrid flame retardant is prominent in manufacturing strandboard with both good fire retardant and satisfying physico-mechanical properties.


Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3979
Author(s):  
Anna Strąkowska ◽  
Sylwia Członka ◽  
Karolina Miedzińska ◽  
Krzysztof Strzelec

The subject of the research was the production of silsesquioxane modified rigid polyurethane (PUR) foams (POSS-Cl) with chlorine functional groups (chlorobenzyl, chloropropyl, chlorobenzylethyl) characterized by reduced flammability. The foams were prepared in a one-step additive polymerization reaction of isocyanates with polyols, and the POSS modifier was added to the reaction system in an amount of 2 wt.% polyol. The influence of POSS was analyzed by performing a series of tests, such as determination of the kinetics of foam growth, determination of apparent density, and structure analysis. Compressive strength, three-point bending strength, hardness, and shape stability at reduced and elevated temperatures were tested, and the hydrophobicity of the surface was determined. The most important measurement was the determination of the thermal stability (TGA) and the flammability of the modified systems using a cone calorimeter. The obtained results, after comparing with the results for unmodified foam, showed a large influence of POSS modifiers on the functional properties, especially thermal and fire-retardant, of the obtained PUR-POSS-Cl systems.


Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 932
Author(s):  
Kamila Sałasińska ◽  
Maciej Celiński ◽  
Kamila Mizera ◽  
Mateusz Barczewski ◽  
Paweł Kozikowski ◽  
...  

In this paper, the fire behavior of unsaturated polyester resin (UP) modified with L-histidinium dihydrogen phosphate-phosphoric acid (LHP), being a novel intumescent fire retardant (IFR), was investigated. Thermal and thermomechanical properties of the UP with different amounts of LHP (from 10 to 30 wt. %) were determined by thermogravimetric analysis (TG) as well as dynamic mechanical thermal analysis (DMTA). Reaction to small flames was studied by horizontal burning (HB) test, while fire behavior and smoke emission were investigated with the cone calorimeter (CC) and smoke density chamber. Further, the analysis of volatile products was conducted (TGA/FT-IR). It was observed that the addition of LHP resulted in the formation of carbonaceous char inhibiting the thermal decomposition, burning rate and smoke emission. The most promising results were obtained for the UP containing 30 wt. % of LHP, for which the highest reduction in maximum values of heat release rate (200 kW/m2) and total smoke release (3535 m2/m2) compared to unmodified polymer (792 kW/m2 and 6895 m2/m2) were recorded. However, some important disadvantage with respect to water resistance was observed.


1983 ◽  
Vol 1 (2) ◽  
pp. 145-154 ◽  
Author(s):  
John V. Beninate ◽  
Brenda J. Trask ◽  
Timothy A. Calamari ◽  
George L. Drake

Durable phosphorus-based flame retardants were applied to twill fabrics con taining cotton and wool to study the effect of wool on the flame retardancy and physical properties of the blend fabrics. The presence of wool in untreated blend fabrics caused burning rates to decrease and oxygen index values to increase as wool content increased in the blends. These effects were also observed in cotton/ wool blends treated with low levels of the Thps-urea-TMM flame retardant, but were less pronounced in fabrics treated at high levels. Thermogravimetric analyses were conducted to study the thermal degradation of the treated and untreated fabrics. The presence of wool in treated blend fabrics did not sig nificantly change strength retention, area shrinkage and wrinkle recovery values in comparison to similarly treated 100% cotton fabrics.


1993 ◽  
Vol 11 (5) ◽  
pp. 442-456 ◽  
Author(s):  
Jun Zhang ◽  
Michael E. Hall ◽  
A. Richard Horrocks

This paper is the first in a series of four which investigates the burning behaviour and the influence of flame retardant species on the flam mability of fibre-forming polymer and copolymers of acrylonitrile. A pressed powdered polymer sheet technique is described that enables a range of polymer compositions in the presence and absence of flame retardants to be assessed for limiting oxygen index, burning rate and char residue deter minations. The method offers a rapid, reproducible and convenient means of screening possible flame retardant systems, and LOI values compare favourably with those of films and fabrics comprising the same polymeric type. Burning rates, however, are sensitive to changes in physical sample character such as form (film vs. powder sheet) and density. Thus the technique forms an excellent basis for the generation of burning data which will enable comprehensive studies of acrylic polymer flammability and flame retardancy to be undertaken.


Author(s):  
Lyubov Vakhitova ◽  
◽  
Nadiya Taran ◽  
Konstantin Kalafat ◽  
◽  
...  

Purpose. Identification of the main directions of evolution of scientific researches concerning development and improvement of fire protective reactive coatings of intumescent type for steel constructions. Methods. Analysis of literature sources, study and generalization of information, classification and modeling of chemical processes. Results. As a result of the performed researches it has been shown that of all the developed reactive fire protection systems for increasing the fire resistance of steel structures the intumescent composition of ammonium polyphosphate/ pentaerythritol / melamine / polymer is the most widespread and economically justified. To reduce the cost of fire protection measures, it is necessary to improve the coatings of the intumescent type in the following main areas: increasing of fire protection efficiency with a decrease in the thickness of the fire protection layer; prolongation of life time with strengthening of resistance to external factors; reducing the cost of the prescription composition of intumescent paint due to the use of nanomaterials. Scientific novelty. It has been established that nanoclays, nanooxides of metals and silicon, LDH compounds and their analogues should be considered the most promising and multifunctional. The presence of nanomaterials in intumescent compositions allows to increase the environmental parameters of fire-retardant treatment due to the rejection of halogen flame retardants, boron compounds, formaldehyde resins. In addition, the presence of nanocompounds in intumescent coatings significantly reduces smoke in fire. Practical significance. The conclusions obtained from the literature review are of practical importance for the development of new approaches to the design of fire-fighting materials with improved performance through the use of nanomaterials, which provides a strong fire retardant foam char layer and provides rigidity of the insulation frame.


Sign in / Sign up

Export Citation Format

Share Document