Polyethylene terephthalate (PET) with high molecular weight can not be obtained due to backward reaction at equilibrium reaction by decreasing the byproduct removal rate because degree of polymerization(DP) increases and viscosity increase as reaction proceeds at the finishing stage of PET synthesis.
Therefore many types of reactor have been developed and presently are used to resolve this problems.
In this study to resolve this problems and enhance efficiency of polymerization Rotating Drum-type reactor was developed and its efficiency was tested.
Bis-2-hydroxy ethyl terephthalate (BHET) monomer is fed into the reactor of which temperature is kept 280℃.
Then volatile byproduct (EG) is continuously removed from the reaction mixture by controlling surface renewal time and pressure and product is abtained. Catalist used was $Sb_2O_3$ and stabilizer is not used.
Good result is obtained by giving the surface renewal action, the considerable factor to remove volatile byproduct.
Especially, as surface renewal time decreases to 0.5 sec, it was found that reactor efficiency increase rapidly.
Testing pressure with surface renewal action, pressure has to be kept about 1 torr when there is no surface renewal action but when there is surface renewal action final product can be obtained when pressure is kept about 20 torr.
