超高氮量硝化纤维素的塑化及性能表征OA

In order to study the plasticization processing of ultra-highly nitrated nitrocellulose(UHNC),the effects of dissolved cottons mass ratio(solvent/UHNC),solvent ratio(EtOH/AC),plasticizer,and plasticization time on the plasticizing effect of UHNC were studied by using ethanol-acetone as the solvent to plasticize NC with a nitrogen content of 13.45％via a conical twin-screw extruder.The plasticizing effect,morphology,structure,mechanical properties and combustion properties of UHNC were characterized by HAAKE MinLab Ⅱ hybrid rheometer,FE-SEM,density measuring instrument,universal tensile tes-ting instrument and high-speed camera.The results show that the optimal mass ratio is achieved with the dissolved cotton mass ratio(solvent/UHNC)of 1∶1 and the solvent ratio(EtOH/AC)of 2∶3.During the plasticization process,the apparent vis-cosity of the samples increases with the extension of the plasticization time.When the plasticizing time exceeds 90minutes,the macroscopic morphology,surface and internal defects of the UHNC products are significantly improved.When the plasticizing time is 120minutes,the sample exhibits the best density(1.571g/cm3)and mechanical properties(tensile strength is 37.97MPa).The addition of DBP and DOP increased the elongation at break of the sample by 28.1％and 15.7％,respec-tively.The apparent burning rate of the sample under normal temperature and pressure decreases with an increase in DBP and DOP content,decreasing by 16.6％and 18.7％,respectively.