Synthesis And Feasibility Study Of Poly(p-phenylenebenzobisoxazole)

poly(p-phenylenebenzobisoxazole)(PBO) fiber has a wide range of application prospects due to its high modulus, strength and heat resistance. Though many studies have been conducted on the preparation and property of PBO, non industrial production line of PBO is built in domestic at present because of high difficulties in preparation and processing. In this thesis, we carry out an easy way to sythesize high quality 4,6-diaminoresorcinol(DAR) of which is the most important monomer to prepare PBO. Then, PBO is synthesized by DAR and terephthalic acid(PTA). On this basis, we prove the feasibility of industrialization of the PBO project andthe following results are obtained.1. Firstly, 4,6-diaceticresoriol was synthesized by Friedel-Crafts reaction using resoriol and acetic anhydride; then dioxime was obtained when reacting with hydroxylammonium chloride; thereafter DAR monomer was got by Beckmann rearrangement; finally, DAR was purified with a product yield of 17.0%. by recrystallization.The PBO polycondensation reaction was conducted between self-synthesized DAR and commercial PTA. The polymer was verified by the viscosity analysis,infrared analysis, elemental analysis, and thermal analysis, and the viscosity average molecular weight of sample is 3.6×104 g/mol.3. Based on the lab test result, a scale-up experiment was discussed by use the technology of Chongqing Chemical Engineering Design &Research Institute(CCEDRI) and Chongqing Wintinwe Chlor-alkali Company. A pilot plant with a scale of 110 kg, which contained synthetic device and spinning device, was designed by these two companies.4. By benefit and technical risk analysis, the overall risk of the project is controllable,and the potential of the project is proved good, so that the project construction scheme is feasible after further improved.