Effect of Et3Al and 9,9-bis(methoxymethyl)fluorine on propylene polymerization at high temperature with TiCl4/MgCl2 catalysts

A study of the effect of ET3Al and a diether, 9,9-bis(methoxymethyl)fluorine (BMMF), on propylene polymerization at high temperature with the use of MgCL2-supported catalysts is reported. BMMF could be extracted from a TiCl4/MgCl2/BMMF catalyst by Et3Al at 100degreesC, and Et3Al is an efficient chain-transfer agent in the presence of BMMF at 100degreesC. The results obained from differential scanning calorimetry (DSC) and C-13 NMR spectroscopy showed that the isotactic poly(propylene) (iPPs) produced by the catalysts containing ethylene units. This phenomenon was not found in the iPP chains obtained with donor ar 100degreesC. It is suggested that the decomposition of Et3Al did not take place in the absence of any donar and took place in the presence of BMMF at 100degreesC. [GRAPHIC] C-13 NMR spectrum of an iPP sample.