Method of utilizing dinuclear amine imine magnesium complex to catalyze caprolactone polymerization

Abstract

The invention discloses a method of utilizing dinuclear amine imine magnesium complex to catalyze caprolactone polymerization. The method includes: taking the dinuclear ammine imine magnesium complexas a catalyst and epsilon-caprolactone as a raw material to catalyze epsilon-caprolactone polymerization without water and oxygen and under gas protection to obtain poly caprolactone. The dinuclear amine imine magnesium complex which is own-developed is taken as the catalyst for caprolactone ring-opening polymerization reaction, the catalyst is simple in preparation method, low in cost, high in product yield, diverse in structure and high in catalytic activity, three-dimensional selectivity and reaction rate, metal center magnesium is coordinated with N, N atoms of ligand, and no cocatalyst isneeded; obtained polymer is narrow in molecular weight distribution, controllable in molecular weight and high in yield.

Description

technical field

[0001] The invention relates to a method for catalyzing the polymerization of caprolactone, in particular to a method for catalyzing the polymerization of caprolactone by using a dinuclear amine imine magnesium complex. Background technique

[0002] With the enhancement of people's awareness of environmental protection, the development of degradable biomaterials that can reduce environmental pollution has become one of the important research fields of polymer materials. Polylactone is a biodegradable, green and environment-friendly polymer material, and it has attracted more and more attention as a substitute for petroleum products. In the natural living environment, waste polylactone materials can be completely decomposed into small molecules by microorganisms in the soil. Because polyester is non-toxic, non-irritating, and has good biocompatibility, it is widely used in medical and environmental protection fields, such as surgical sutures, packaging, drug ...

Examples

Embodiment 1

[0035] The structural formula of the ligand used is the above formula (A), where R is hydrogen, and the reaction process is as follows: under a nitrogen atmosphere, slowly add 5 mL of benzyl alcohol tetrahydrofuran solution (2.0 mol / L) to an equimolar amount of Mg( n Bu) 2 Hexane solution (2.0 mol / L, 5 mL) was reacted for 1 hour, 2.09 g of the ligand was dissolved in 20 mL of dry toluene, and added to Mg( n Bu) 2 In the reaction mixture with benzyl alcohol, after adding, the reaction liquid was naturally raised to room temperature, and then heated to 60°C for 3 hours. After the reaction, the solvent was vacuum-dried, and the residue was washed with dry n-hexane, filtered, and then the product was collected and dried. Weighed to obtain 2.75 g of solid, yield 81.2%.

Embodiment 2

[0037] The structural formula of the ligand used is the above formula (A), where R is a methyl group, and the reaction process is as follows: under a nitrogen atmosphere, slowly add 5 mL of benzyl alcohol tetrahydrofuran solution (2.0 mol / L) to an equimolar amount of Mg( n Bu) 2 Hexane solution (2.0 mol / L, 5 mL) was reacted for 1 hour, 2.37 g of the ligand was dissolved in 20 mL of dry toluene, and added to Mg( n Bu)2 and benzyl alcohol reaction mixture, after adding, the reaction liquid was naturally raised to room temperature, and then heated to 40 ° C for 12 hours, after the reaction was completed, the solvent was vacuum-dried, and the residue was washed with dry n-hexane, filtered, and then the product was collected and dried Weighed to obtain 3.27 g of solid, yield 89.1%.

Embodiment 3

[0039] The structural formula of the ligand used is the above formula (A), where R is ethyl, and the reaction process is as follows: under a nitrogen atmosphere, slowly add 5 mL of benzyl alcohol tetrahydrofuran solution (2.0 mol / L) to an equimolar amount of Mg( n Bu) 2 Hexane solution (2.0 mol / L, 5 mL) was reacted for 1 hour, 2.65 g of the ligand was dissolved in 30 mL of dry toluene, and added to Mg( n Bu) 2 In the reaction mixture with benzyl alcohol, after adding, the reaction liquid was naturally raised to room temperature, and then heated to 50 ° C for 4 hours. After the reaction was completed, the solvent was vacuum-dried, and the residue was washed with dry n-hexane, filtered, and then the product was collected and dried. Weighed to obtain 3.17 g of solid, yield 80.3%.

technical field

[0001] The invention relates to a method for catalyzing the polymerization of caprolactone, in particular to a method for catalyzing the polymerization of caprolactone by using a dinuclear amine imine magnesium complex. Background technique

[0002] With the enhancement of people's awareness of environmental protection, the development of degradable biomaterials that can reduce environmental pollution has become one of the important research fields of polymer materials. Polylactone is a biodegradable, green and environment-friendly polymer material, and it has attracted more and more attention as a substitute for petroleum products. In the natural living environment, waste polylactone materials can be completely decomposed into small molecules by microorganisms in the soil. Because polyester is non-toxic, non-irritating, and has good biocompatibility, it is widely used in medical and environmental protection fields, such as surgical sutures, packaging, drug ...

Examples

Embodiment 1

[0035] The structural formula of the ligand used is the above formula (A), where R is hydrogen, and the reaction process is as follows: under a nitrogen atmosphere, slowly add 5 mL of benzyl alcohol tetrahydrofuran solution (2.0 mol / L) to an equimolar amount of Mg( n Bu) 2 Hexane solution (2.0 mol / L, 5 mL) was reacted for 1 hour, 2.09 g of the ligand was dissolved in 20 mL of dry toluene, and added to Mg( n Bu) 2 In the reaction mixture with benzyl alcohol, after adding, the reaction liquid was naturally raised to room temperature, and then heated to 60°C for 3 hours. After the reaction, the solvent was vacuum-dried, and the residue was washed with dry n-hexane, filtered, and then the product was collected and dried. Weighed to obtain 2.75 g of solid, yield 81.2%.

Embodiment 2

[0037] The structural formula of the ligand used is the above formula (A), where R is a methyl group, and the reaction process is as follows: under a nitrogen atmosphere, slowly add 5 mL of benzyl alcohol tetrahydrofuran solution (2.0 mol / L) to an equimolar amount of Mg( n Bu) 2 Hexane solution (2.0 mol / L, 5 mL) was reacted for 1 hour, 2.37 g of the ligand was dissolved in 20 mL of dry toluene, and added to Mg( n Bu)2 and benzyl alcohol reaction mixture, after adding, the reaction liquid was naturally raised to room temperature, and then heated to 40 ° C for 12 hours, after the reaction was completed, the solvent was vacuum-dried, and the residue was washed with dry n-hexane, filtered, and then the product was collected and dried Weighed to obtain 3.27 g of solid, yield 89.1%.

Embodiment 3

[0039] The structural formula of the ligand used is the above formula (A), where R is ethyl, and the reaction process is as follows: under a nitrogen atmosphere, slowly add 5 mL of benzyl alcohol tetrahydrofuran solution (2.0 mol / L) to an equimolar amount of Mg( n Bu) 2 Hexane solution (2.0 mol / L, 5 mL) was reacted for 1 hour, 2.65 g of the ligand was dissolved in 30 mL of dry toluene, and added to Mg( n Bu) 2 In the reaction mixture with benzyl alcohol, after adding, the reaction liquid was naturally raised to room temperature, and then heated to 50 ° C for 4 hours. After the reaction was completed, the solvent was vacuum-dried, and the residue was washed with dry n-hexane, filtered, and then the product was collected and dried. Weighed to obtain 3.17 g of solid, yield 80.3%.

Images