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Use of pyrazoles as ligands greatly enhances the catalytic activity of titanium iso-propoxide for the ring-opening polymerization of l-lactide: a cooperation effect.

ABSTRACT: Using TiOⁱPr₄ with a pyrazole ligand for one-pot LA polymerization improved catalytic activity compared with using TiOⁱPr₄ only. At 60 °C, TiOⁱPr₄ with ^furPz exhibited a higher catalytic activity (approximately 3-fold) than TiOⁱPr₄. At room temperature, TiOⁱPr₄ with ^BuPz exhibited a higher catalytic activity (approximately 17-fold) than TiOⁱPr₄. High molecular mass PLA (M _{n_GPC} = 51 100, and Đ = 1.10) could be produced by using TiOⁱPr₄ with ^furPz in melt polymerization ([TiOⁱPr₄] : [^furPz] = 1000 : 1 : 1 at 100 °C, 240 min). The crystal structure of ^MePz₂Ti₂OⁱPr₇ revealed the cooperative activation between two Ti atoms during LA polymerization.

SUBMITTER: Wang TF

PROVIDER: S-EPMC9057761 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Use of pyrazoles as ligands greatly enhances the catalytic activity of titanium iso-propoxide for the ring-opening polymerization of l-lactide: a cooperation effect.

Wang Tzu-Fang TF Kosuru Someswara Rao SR Yu Shu-Chun SC Chang Yung-Chi YC Lai Hsin-Yu HY Chang Yu-Lun YL Wu Kuo-Hui KH Ding Shangwu S Chen Hsuan-Ying HY

RSC advances 20201109 67

Using TiOiPr4 with a pyrazole ligand for one-pot LA polymerization improved catalytic activity compared with using TiOiPr4 only. At 60 °C, TiOiPr4 with furPz exhibited a higher catalytic activity (approximately 3-fold) than TiOiPr4. At room temperature, TiOiPr4 with BuPz exhibited a higher catalytic activity (approximately 17-fold) than TiOiPr4 ...[more]

PMID: 35519227

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