Study On The Thermal Degradation Of Treated Wool (K₂MF₆ Systems)

This thesis consists of three chapters.In the first chapter, the type, effect and development of flame-retardants on treatment of wool were reviewed, as well as the resent studies on the thermal degradation of wool treated with flame-retardants. The purpose, significance and result in this paper were also summarized. Seventy-eight references were cited.In the second chapter, wool were treated by K2TiF6 and dicarboxylic acids system, K2ZrF6 and dicarboxylic acids system, K2TiF6 and inorganic compounds system. The flame retardance and thermal degradation of wool treated with flame retardanrs were studied in air by thermal analysis, IR, limiting oxygen index and char yield. Compared with pure wool, in the treated wool, there is (a) lowing in thermal degradation onset temperature, (b) increase in limiting oxygen index, (c) increase in char yield, and (d) decrease in energies of activation. Effect of the different systems on degradation behaviors has been proposed. During the process of wool, flame-retardants catalyze the thermal decomposition of wool, and lower decomposition temperature and burning ability of wool, and increase LOI value and char index. The presence of decarboxylic acids stabilizes K2TiF6 or K2ZrF6. The combination of K2TiF6 and inorganic compounds increase the flame retardance of wool.In the third chapter, the flame retardance of wool treated with TBPA and inorganic compounds was characterized by systemic analysis methods, and thermal degradation behavior of treated wool was minutely studied. From the different properties of pure and treated wool, we know that the flame retardance of treated wool was greatly improved. Moreover, the flame retardant mechanism and effects on the thermal degradation of samples for different flame-retardant reagents were proposed. Hydrogen bromide, which operates in the gaseous phase, formed in the thermal degradation of wool as radical scavengers block the process of flame, which leads to slow down major weight loss. And inorganic compounds operate in the solid phase catalyzing the decomposition of wool and forming a heavy char.