Microstructure of polypropylene and active center in Ziegler-Natta catalyst: effect of novel salicylate internal donor

	Microstructure of polypropylene and active center in Ziegler-Natta catalyst: effect of novel salicylate internal donor
	Zhou, Qian 1; Wang, Ailian 1; Li, Huayi 2; Luo, Zhi 1; Zheng, Tao 1; Zhang, Liaoyun 1; Hu, Youliang 2
刊名	RSC ADVANCES
	2016
卷号	6 期号:79 页码:75023-75031
英文摘要	Five salicylates with different sizes of hydrocarbon substituents were firstly synthesized and employed as ecofriendly internal donors of the Ziegler-Natta catalyst for propylene polymerization. The influences of these salicylates and traditional, industrial, internal donor diisobutyl phthalates on the microstructure of polypropylene and active center in a Ziegler-Natta catalyst were studied. It was found that the catalyst activities of the catalysts containing salicylate internal donors with a proper volume were higher than the catalysts containing diisobutyl phthalate internal donors. GPC results showed that the molecular weights of polypropylene prepared by salicylate internal donors were lower than those prepared by diisobutyl phthalate, which indicated that the polypropylene chains produced by salicylate internal donors were easier to transfer than those prepared by diisobutyl phthalate internal donors. Deconvolution of the GPC curves exhibited that as the volume of the salicylate internal donor increased some of the active centers for low molecular weight transferred into the active centers for high molecular weight. The results of C-13-NMR and SSA both suggested that a salicylate internal donor with an appropriate catalyst size volume was beneficial for increasing the isotactic sequence length, isotacticity index and regular triads "mm" of polypropylene. However, further increasing the volume of the salicylate internal donor in a catalyst would lead to the polypropylene chain containing more stereo-defects. Moreover, the active centers with different stereospecificity parameters, p(iso), in the catalyst could explain the trend of stereo-defects in polypropylene chains when different internal donors were used. In addition, it was found that the isotactic sequence length and isotacticity index of polypropylene prepared by isobutyl 2-benzyloxy3,5-isopropyl benzoate were close to that produced by a diisobutyl phthalate internal donor. Moreover, the lamella thickness distribution of the polypropylene produced by a salicylate internal donor was broad, which might have potential application for expanded polypropylene materials.
收录类别	SCI
语种	英语
内容类型	期刊论文
源URL	[http://ir.iccas.ac.cn/handle/121111/35364]
专题	化学研究所_工程塑料实验室
作者单位	1.Univ Chinese Acad Sci, Coll Chem & Chem Engn, Beijing 100049, Peoples R China 2.Chinese Acad Sci, Beijing Natl Lab Mol Sci, Inst Chem, CAS Key Lab Engn Plast, Beijing 100190, Peoples R China
推荐引用方式 GB/T 7714	Zhou, Qian,Wang, Ailian,Li, Huayi,et al. Microstructure of polypropylene and active center in Ziegler-Natta catalyst: effect of novel salicylate internal donor[J]. RSC ADVANCES,2016,6(79):75023-75031.
APA	Zhou, Qian.,Wang, Ailian.,Li, Huayi.,Luo, Zhi.,Zheng, Tao.,...&Hu, Youliang.(2016).Microstructure of polypropylene and active center in Ziegler-Natta catalyst: effect of novel salicylate internal donor.RSC ADVANCES,6(79),75023-75031.
MLA	Zhou, Qian,et al."Microstructure of polypropylene and active center in Ziegler-Natta catalyst: effect of novel salicylate internal donor".RSC ADVANCES 6.79(2016):75023-75031.