| The technology for manufacturing cellulose fiber traditionally by Viscose spinning is of long history and well-developed in industry, but it has many disadvantages such as complex process, large energy consume, and serious pollution to the environment during it production process. The innovation on the traditional technology to develop new ones for manufacturing cellulose fiber with non-pollute to the environment is, therefore, drawing great attentions of the experts. In addition, modifications in fire-retardant on cellulose fiber, especially by employing non-halogen containing, little toxic, little smoke and high effective fire retardants is also one of hot research pot in the art.Cellulose fiber made from cellulose carbamate(CC) is named eco-friendly cellulose fiber. In this paper, an eco-friendly fire-retardant cellulose fiber was prepared. Based on the investigation on the changes of the cellulose structure after its activation by alkali, ammonia, electronic beam radiation, steam explosion, ammonia explosion and ultrasonic respectively, the synthesis of the cellulose carbamate was discussed. In addition, three phosphorus based fire retardants were synthesis. Thus, the fire retardant cellulose fiber was prepared by blending spinning. And at last, the fire retardant properties of the fiber and the fire retardant mechanism were discussed.The innovated content in this paper are as follows:1 . The important aspect of this paper is that through physical or chemical pretreatment to cellulose, the active surface was increased, the micro-cavity structure was improved, the penetration, diffusion and swelling of the agent to it was promoted, and therefore the activity of the cellulose was enhanced. The active methods of electronic beam radiation, steam explosion, ammonia explosion are firstly employed in domestic to activate the cellulose and follow to prepare CC, among which ammonia explosion method has not been reported yet abroad. We comprehensively and systematically studied the changes of the structures and properties of cellulose in the process of cellulose activation and reaction by means of various techniques, including Fourier Transform Infrared Absorption Spectrum(FTIR),Wide-angle X-rayIVDiffraction(WAXD?Scanning Electron Microscopy(SEM?Optical Microscopy, Differential Scanning Calorimetry(DSC),Kjeldahl Nitrogen Element Analysis, Degree of Polymerization of Cellulose and Fiber Mechanical Property Measurement etc. The results show that the degree of the polymerization decreases, the distribution of molecular weight gets narrow, and its reactivity rises. Electronic radiation has hardly effects on the lattice and crystallinity, but the lattice form converted from cellulose I to cellulose II and the crystallinity of cellulose decreased after ammonia explosion.2. Three phosphorus based fire retardants, l,2-bis(2-oxy-5,5- dimethyl-l,3,2-dioxaphosphorinane-2,2'-disulfide)(DDPS),l,2-bis(2-oxy-5,5-dimethyl-l,3,2-di oxaphosphorinane phosphoryl amide) ethane (DDPN) and l,2-bis(2-oxy-5,5-dimethyl-l,3,2- dioxaphosphorinane -2,2- disulfide phosphoryl amide) ethane (DDPSN) , were synthesized. All the three fire retardants were identified by elemental analysis > TG-DTA, DSC, FTIR,'HNMR, MS. Among them, DDPS is the best with an initial decomposition temperature of 205癈 and good carbon-forming ability, and DDPN is the worst with an initial decomposition temperature of 285癈 and bad carbon-forming ability. In addition, the synthesis technology was optimized and the yields are all above 85%.3. Nonisothermal kinetics researches on DDPS were carried out using dynamic thermalgravity. The aspect activation energy and A was calculated using Kissinger and integral methods. Based on the thermalgravity line of DDPS at an elevating rateof 1 0癈/min, its thermal decomposition function was set up as [- ln(l - a)]1/3 =kt ,which shows that the mechanism of thermal decomposition of DDPS is random nuclear f...
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