“Polydentate phosphine oxides as new electron-donor components of titanium-magnesium catalysts for the synthesis of isotactic poly(1-butene)”

Application of successive self-nucleation and annealing (SSA) to poly(1-butene) prepared by Ziegler–Natta catalysts with different external donors

“…In this study, poly(1-butene) was prepared by Ziegler-Natta catalysts using silane external donors. The inuence of steric hindrance of the external donor on the structure of poly-(1-butene) was studied by DSC and 13 C NMR. The crystallization behavior and sequence length distribution of poly(1-butene) samples were studied by the successive self-nucleation and annealing calorimetric technique.…”

“…Analysis of 13 C NMR spectrum. The high-temperature 13 C NMR spectrum of the iPB is shown in Fig. 2.…”

“…However, because the stereoregularity of the obtained iPB was higher, the content of atactic PB was very low; thus, the intensity of the peak of the atactic structure was very weak and the instrumental resolution was lower. Therefore, the stereoregularity of iPB was difficult to accurately calculate from 13 C NMR.…”

“…Although there are many reports on the inuence of external donors on propylene polymerization and polypropylene, investigations of the effect of external donors on 1-butene polymerization and poly(1-butene) are few. Kudinova et al 13 reported that use of polydentate phosphine oxides as electron donors for TiCl 4 -MgCl 2 catalysts could obtain highly isotactic poly-(1-butene) and the isotactic index could reach 92.4% when the external donor was iso-AmP(O) (CH 2 OMe) 2 . Ren et al 14 studied diphenyl-dimethoxysilane and cyclohexyl-methyldimethoxysilane as external donors for TiCl 4 -MgCl 2 catalysts.…”

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Alkoxysilane compounds R 1 R 2 Si(OMe) 2 were used as external donors in 1-butene polymerization with MgCl 2 -supported Ziegler-Natta catalysts. The structure of the prepared iPB was characterized by 13 C NMR and GPC. The thermal properties of poly(1-butene) (iPB) were studied by DSC.

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