| Flame retardant (FR) is a kind of additive which can enhance the material's flame resistance. Among the organic flame retardants, brominated and phosphorus- containing flame retardants are the most important. Although "dioxin" problem of polybromodiphenyl ethers made it be challenged, brominated flame retardant will keep its leading position in FRs. In this dissertation, two brominated FRs and two phosphorous-containing FRs were prepared and their preliminary applications in polymers were also discussed.The first brominated FR was a novel, high efficient and low toxic flame retardant decabromo-diphenyl ethane (DBDPE), the ideal substitution of decabromo-diphenyl ether. DBDPE has a high bromine content, with low toxicity when burns. It can be used widely in polyolefin, engineering plastics, electric wire and cable, rubber and so on. First of all, the key intermediate product of DBDPE-- diphenylethane (DPE) was studied. In an easy-to-industrialized way, two methods were choosed. First was alkylation reaction, this method used benzene and dichloroethane as raw materials. The optimum processing conditions were determined, furthermore, the recycle of benzene and catalyze were also discussed. Second was coupling reaction, using benzyl chloride and powdered iron as raw materials. After an orthogonal experiment, the process optimization was established. In addition, the effects of the influencing factors were compared. During the post-treatment, the redundant iron was resolved by acid, then after separation, the product was directly recrystallized. This process has many advantages such as high productivity, low equipment investment, simple operation and low energy consumption etc. The comparison between these methods indicated that: the former alkylation's has superiorities in feed stock cost, but the latter has vantages in environmental protection, operation and equipment investment. Subsequently, the FR DBDPE was synthesized. The process was optimized. Firstly solved problem was how to dropwise continuously in liquid state. Secondly was to upraise the quality of products. After a long-term grind and baking under high temperature, the product reached high quality.The second synthesized brominated FR was a new reactive-type flame retardant 2,3-Dibromosuccinic Anhydride. Contrast to the additive FR, reactive FRs seldom interfere with the material's excellent performance, and bestow the material permanent flame retardancy at the same time. By a direct addition reaction, bromine was utilized utterly, without corrosion to the equipments. The solvent selected has no toxicity, no pollution and easy to recycled, while the reaction needs no catalyst. To purify the rough product, a new method was established, we called it distillatory recrystallization.The first phosphorus-containing FR synthesized was flame retarding plasticizer isopropylphenyldiphenyl phosphate ester (IPP). Flame retarding plasticizer has double functions: good flame retardancy and plasticity as well, as is appreciated by many consumers. The most popular flame retarding plasticizer was trimethylphenyl phosphate ester (TCP) once, but it is toxic and costs high. IPP has low toxicity and cost, with outstanding performance as TCP, which makes it the substitution of TCP. IPP was synthesized from POCl3, phenol and propene etc. The alkylation catalyst phenol sulfonic acid was selected. Meanwhile, the optimum alkylation and esterification reaction conditions were determined. During the after-treatment process, the esterification catalyst AlCl3 was removed with a physical and chemical combined process. This process has advantages as simple operation, low pollution and high quality of products. Eventually, the quality inspection manifested that the product coincided the classy of the national standard. The last FR was an intumescent flame retardant (IFR), N, N'-di (2-oxo-5, 5-dimethyl -1, 3, 2-dioxy-phosphacyclohexane)-2, 2'-m-phenylene diamine (BPMPA).IFR was considered the develop direction of the FRs. It can be used alone, nee... |
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