摘要:

AbstractThe combustion of polypropylene flame‐retarded by the synergistic action between Sb2O3and bromine‐containing flame retardants has been studied. From the relationship between a number of the variables, a parameter quantatively reflecting the flame retardant effect has been found. With the addition of flame retardant, the rate of weight loss, the CO and CO2emission rates and heat release all decrease while smoke density increases. These effects were considered to depend on the concentration of HBr gas in the pyrolysates released into the gas phase (i.e., dWHBr/dW, HBr flux ensity), and the following equations were obtained:\documentclass{article}\pagestyle{empty}\begin{document}$$ \frac{1}{W_0}\left(\frac{\rm d{W}}{\rm d{t}}\right)_{\max} \propto\left(\frac{\rm d{W_{HBr}}}{\rm d{W}}\right)^{-0.64}\quad\quad {\rm and}\quad\quad\eta^{\rm *} =\frac{W_{\rm[C], CO + CO_2}}{W_{0[\rm C]}}\,\propto \left(\frac{\rm d{W_{HBr}}}{\rm d{W}}\right)^{-0.37} $$\end{document}η*(dW/dt)max, which approximately corresponds to the oxidation velocity of pyrolized hydrocarbon, is inversely proportional to the HBr flux density. As the conversion of CO to CO2was almost independent of the amount of flame retardants added, the flame retardant effect of bromine‐containing flame retardants was considered to be a retardant effect of the initial oxidation reaction at the gas liquid interface. Moreover, η* is almost proportional to the combustion efficiency η, which was obtained from the heat release measured in the flaming region. The heat release is therefore considered to be governed by the HBr flux

ISSN:0308-0501    

DOI:10.1002/fam.810060102

出版商:Wiley Heyden Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractThe thermal behaviour in air of lignins modified by chlorophosphazenes as well as that of the raw materials of lignins has been investigated using thermogravimetry (TG), derivative thermogravimetry (DTG) and differential thermal analysis (DTA). The thermogravimetry and derivative thermogravimetry studies of lignins modified by chlorophosphazenes have shown their thermal resistance to be relatively higher than that of the intital raw materials of lignins in concrete kraft lignin and sodium ligninosulfonate. The differential thermal studies have demonstrated that the thermal degradation of products investigated takes place via exothermic processes. The lignins modified by chlorophosphazenes have been shown to be thermal and flame‐resistant material

ISSN:0308-0501    

DOI:10.1002/fam.810060103

出版商:Wiley Heyden Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractThermal analysis and limiting oxygen index flammability tests were used for elucidation of details in phosphorous‐nitrogen synergism in cotton modified with methylol phosphonopropionamide and subsequently hydrolyzed by acid. The results indicate that not all the phosphorus incorporated into the material is effective for flame retardancy purposes in the condensed phase. The comparison of modified and acid hydrolyzed cotton has shown the important influence of nitrogen in the structure of the flame retardant. A simplified theory of nitrogen‐phosphorus synergism, considering this influence, is propo

ISSN:0308-0501    

DOI:10.1002/fam.810060104

出版商:Wiley Heyden Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractThermal degradation products of nitrogen‐containing polymeric materials were analysed for hydrogen cyanide. A spectrophotometric method was used for the determination of cyanides using the formation of a characteristic absorption peak of cyanonickel(II) ion in the ultraviolet spectral region. Pyrolysis and thermooxidation products were studied and conclusions on the reproducibility of the degradation process were drawn. The effect of temperature on the quantity of hydrogen cyanide formed was studied as wel

ISSN:0308-0501    

DOI:10.1002/fam.810060105

出版商:Wiley Heyden Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractThe fire risk posed by soft furnishings such as bedding materials and upholstered furniture and the strategies being developed to reduce the number of fire‐related casualities are reviewed from a Canadian point of view. Statistics from Canada, the United States and the United Kingdom indicate that a substantial reduction in the number of fire deaths would be possible if the ability of assemblies of materials to resist ignition by smokers' materials, such as cigarettes and matches, could be improved. The post‐ignition performance of furnishings that results in generation of heat, smoke and toxic gases is also important from a safety point of view. A need exists for both full‐scale and small‐scale fire tests, and for mathematical modelling for present and future control str

ISSN:0308-0501    

DOI:10.1002/fam.810060106

出版商:Wiley Heyden Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractAn apparatus has been designed and a procedure adopted for studing the oxygen index of materials over a range of pressures. It has been found that the oxygen index falls with increase in pressure so that materials become more flammable, the effect being more marked with the less flammable materials. An empirical method has been devised for predicting the oxygen index at varying pressures.

ISSN:0308-0501    

DOI:10.1002/fam.810060107

出版商:Wiley Heyden Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractIt is demonstrated that he normalized heat load is a suitable parameter for ranking various enclosure fires on a ‘potential for destruction’ scale. This parameter is convertible to the familiar fire resista

ISSN:0308-0501    

DOI:10.1002/fam.810060108

出版商:Wiley Heyden Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractConcentrations of elements were determined in tracheal specimeans of fatal fire casualties and of non‐fire fatalities. Elevated concentrations of antimony, bromine, zinc, chromium, cobalt, iron, lead, cadmium and gold found in the group exposed to the fire environment were associated with deposition of soot. The presence of raised concentrations of antimony in fatalities was found to occur in association with increased content of carboxyhaemoglobin in blood and was greatest in fires involving major destruction of property. A relationship between the increased concentration of this element and the use of antimony containing fire‐retardants in construction materials could not be demonstra

ISSN:0308-0501    

DOI:10.1002/fam.810060109

出版商:Wiley Heyden Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractThis study was performed to establish the appropriate moisture level for textile flammability test specimens. Three investigations were carried out: into the effect of the level of humidity in dwellings; into the moisture content of garments worn at various distances from the body; and into the effect of relatively short exposures to heat on the moisture content of fabrics (simulating the case of a person standing in front of an open fire or space heater). The moisture content of ambient air in dwellings was found to be primarily governed by the moisture content of the air outside and can be quite low, ten to twenty percent, especially in winter (unless, of course, humidifying equipment is used). The moisture content of garment parts which are at some distance from the body (e.g., the loosely fitting parts of skirts) is governed by the relative humidity of the room. Closely fitting parts are more likely to be exposed to ignition sources than closely fitting parts. Fabric specimens exposed at a short distance from an electric space heater had moisture contents similar to specimens which has been oven‐dried and cooled in a desiccator. The results of these studies indicate that oven‐drying is a reasonable conditioning requirement for testing the flammability of apparel and home furnishing fabr

ISSN:0308-0501    

DOI:10.1002/fam.810060110

出版商:Wiley Heyden Ltd.    

年代:1982

数据来源: WILEY

摘要:

AbstractOxidation processes involved in processing, atmospheric ageing and the pre‐burning stages of hydrocarbon polymers are outlined. Open problems based on up‐to‐date knowledge of the mechanisms of oxidation and stabilization processes are considered. Stabilizers used to assist processing and long‐term stability are transformed during their service‐time. Some of the products thus formed, as well as the products of polymer oxidation, should be considered as inherent impurities of polymers and play an active role in the degradation. Because of safety consideration, some of the products have to be protected also against catastrophic oxidation, i.e. burning. Significant changes in the mechanisms of degradation take place in the pre‐burning step in the phases of high temperature oxidation and oxidative pyrolysis. Fuller understanding of the mutual relationships in the mixtures of antioxidants and/or light stabilizers with flame‐retardan

ISSN:0308-0501    

DOI:10.1002/fam.810060111

出版商:Wiley Heyden Ltd.    

年代:1982

数据来源: WILEY