PC ET3113 科思创---At present, the industrial units ofpolycarbonate vinegar basically adopt the interfacepolycondensation phosgene process. The main process is to preparebisphenol sodium salt from bisphenol and caustic soda solution, addphenol at the same time, and then send it to the phosgene reactor,add dichloromethane, pass phosgene for phosgene reaction. After thereaction, send the reaction solution to the polycondensationreactor, add triethylamine and caustic soda solution forpolycondensation
The creep resistance of PC is very good in thermoplasticengineering plastics, even better than that of nylon and POM. Thisis an important sign of its excellent dimensional stability. Stresscracking: (PC products are prone to stress cracking) the internalstress of plastics is mainly caused by the interaction betweenforced oriented macromolecular chains. Residual stress and stresscracking of PC products are prominent problems. When the bendingstrength of PC is flexed and placed for a certain time, microtearing will occur when the bending stress exceeds its limit value.When the molecular weight of PC is more than 24000, it can bear 35MPa, and when the molecular weight is 22000, it is about 20 MPa.Therefore, when the residual stress or the stress of the product isbelow this value, stress cracking will not occur. Even if theproduct only maintains at the micro tearing stage and does notfurther develop, its service performance will not be affected
PC is a medium wear resistant material (but much better thanmetal). It is worse than nylon, polyoxymethylene, chlorinatedpolyether and PTFE, but better than ABS, polysulfone andplexiglass. The wear resistance of PC can be improved by addingsome fillers, such as PTFE and glass fiber, which can reduce thefriction coefficient and wear amount and increase the PV value. PChas good heat resistance and cold resistance. It can be used in therange of - 100 ~ 130 ℃ for a long time. Its load deformationtemperature is high (130 ~ 140 ℃) and is less affected by load;When the embrittlement temperature is below - 100 ℃, even at - 180℃, it will not break like glass. PC has no obvious melting pointand is in melting state at 220 ~ 230 ℃. Because of the rigidity ofmacromolecular chain, its melt viscosity is much higher than otherthermoplastics
