Preparation method of hydroxy-terminated perfluoropolyether compound

Abstract

The invention relates to a preparation method of a hydroxy-terminated perfluoropolyether compound. Perfluoropolyether carboxylic acid or ester used as a raw material is subjected to reducing reaction to obtain the hydroxy-terminated perfluoropolyether compound, wherein hydrogen is used as the reducer of the reducing reaction, an activated carbon supported ruthenium or rhodium catalyst is used as the catalyst, and the reaction is carried out at 80-200 DEG C under the pressure of 10-50MPa. Compared with the prior art, the invention has the advantages of high reaction yield, simple after-treatment and fewer three wastes, and is simple to operate.

Description

technical field

[0001] The invention relates to a preparation method of a hydroxyl-terminated perfluoropolyether compound. Background technique

[0002] Hydroxyl-terminated perfluoropolyether is a very useful fluorine-containing compound, which can be used not only as a disk lubricant, but also as an intermediate for the preparation of fluorine-containing surfactants, fluorine-containing polyurethanes, fluorine-containing medicines, pesticides, and fluorine-containing polymers wait. The hydroxyl-terminated perfluoropolyether can be prepared by reducing perfluoropolyether esterified products, perfluoropolyether carboxylic acid, perfluoropolyether acid halide, etc. with metal hydride. For example, in the patent GB1309401, the inventor uses LiAlH 4 Reduction of linear perfluoropolyether carboxylic acid to prepare hydroxyl-terminated perfluoropolyether; in patents US5220076 and US5237108, the inventor used NaBH 4 Reduction of perfluoropolyether esterification to prepare...

Examples

Embodiment 1

[0031] 200.0g perfluoropolyether carboxylic acid C 3 F 7 O(CF(CF 3 ) CF 2 O) b CF(CF 3 )COOH (weight-average molecular weight 2000) and 10.0g (5%Ru / C) were added to a 250ml Monel alloy autoclave. Stop the reaction, empty the autoclave, remove the catalyst by filtration, distill off a small amount of low-boiling components at 120°C, and the residue weighs 175.6g. Infrared detection shows that the perfluoropolyether carboxylic acid is completely converted into product C 3 F 7 O(CF(CF 3 ) CF 2 O) b CF(CF 3 )CH 2 OH, yield 87.9%.

Embodiment 2

[0033] 152.2g methyl perfluoropolyether carboxylate C 3 F 7 O(CF(CF 3 ) CF 2 O) b CF(CF 3 ) COOCH 3 (weight average molecular weight 3000) and 5.5g (5%Ru / C) were added to a 250ml Monel alloy autoclave, vacuum-nitrogen was replaced three times, hydrogen was introduced to 11MPa, and then the temperature was gradually raised to 130°C, and the reaction was stopped after 8 hours. Empty the autoclave, remove the catalyst by filtration, and distill off the low-boiling components at 125°C. The residue weighs 130.3g. Infrared detection shows that methyl perfluoropolyether carboxylate is completely converted into product C 3 F 7 O(CF(CF 3 ) CF 2 O) b CF(CF 3 )CH 2 OH, yield 86.1%.

Embodiment 3

[0035] 140.2g C a F 2a+1 O(CF(CF 3 ) CF 2 O) b (CF 2 CF 2 CF 2 O) d CF 2 CF 2 COOCH 3 (weight-average molecular weight 2800) and 5.1g (5%Ru / C) were added to a 250ml Monel alloy autoclave, vacuum-nitrogen was replaced three times, hydrogen was introduced to 10MPa, and then the temperature was gradually raised to 140°C, and the reaction was stopped after 7 hours. Empty the autoclave, remove the catalyst by filtration, and distill off the low-boiling components at 125°C. The residue weighs 116.8g. Infrared detection shows that all the raw materials are converted into product C a F 2a+1 O(CF(CF 3 ) CF 2 O) b (CF 2 CF 2 CF 2 O) d CF 2 CF 2 CH 2 OH, yield 83.8%.

technical field

[0001] The invention relates to a preparation method of a hydroxyl-terminated perfluoropolyether compound. Background technique

[0002] Hydroxyl-terminated perfluoropolyether is a very useful fluorine-containing compound, which can be used not only as a disk lubricant, but also as an intermediate for the preparation of fluorine-containing surfactants, fluorine-containing polyurethanes, fluorine-containing medicines, pesticides, and fluorine-containing polymers wait. The hydroxyl-terminated perfluoropolyether can be prepared by reducing perfluoropolyether esterified products, perfluoropolyether carboxylic acid, perfluoropolyether acid halide, etc. with metal hydride. For example, in the patent GB1309401, the inventor uses LiAlH 4 Reduction of linear perfluoropolyether carboxylic acid to prepare hydroxyl-terminated perfluoropolyether; in patents US5220076 and US5237108, the inventor used NaBH 4 Reduction of perfluoropolyether esterification to prepare...

Examples

Embodiment 1

[0031] 200.0g perfluoropolyether carboxylic acid C 3 F 7 O(CF(CF 3 ) CF 2 O) b CF(CF 3 )COOH (weight-average molecular weight 2000) and 10.0g (5%Ru / C) were added to a 250ml Monel alloy autoclave. Stop the reaction, empty the autoclave, remove the catalyst by filtration, distill off a small amount of low-boiling components at 120°C, and the residue weighs 175.6g. Infrared detection shows that the perfluoropolyether carboxylic acid is completely converted into product C 3 F 7 O(CF(CF 3 ) CF 2 O) b CF(CF 3 )CH 2 OH, yield 87.9%.

Embodiment 2

[0033] 152.2g methyl perfluoropolyether carboxylate C 3 F 7 O(CF(CF 3 ) CF 2 O) b CF(CF 3 ) COOCH 3 (weight average molecular weight 3000) and 5.5g (5%Ru / C) were added to a 250ml Monel alloy autoclave, vacuum-nitrogen was replaced three times, hydrogen was introduced to 11MPa, and then the temperature was gradually raised to 130°C, and the reaction was stopped after 8 hours. Empty the autoclave, remove the catalyst by filtration, and distill off the low-boiling components at 125°C. The residue weighs 130.3g. Infrared detection shows that methyl perfluoropolyether carboxylate is completely converted into product C 3 F 7 O(CF(CF 3 ) CF 2 O) b CF(CF 3 )CH 2 OH, yield 86.1%.

Embodiment 3

[0035] 140.2g C a F 2a+1 O(CF(CF 3 ) CF 2 O) b (CF 2 CF 2 CF 2 O) d CF 2 CF 2 COOCH 3 (weight-average molecular weight 2800) and 5.1g (5%Ru / C) were added to a 250ml Monel alloy autoclave, vacuum-nitrogen was replaced three times, hydrogen was introduced to 10MPa, and then the temperature was gradually raised to 140°C, and the reaction was stopped after 7 hours. Empty the autoclave, remove the catalyst by filtration, and distill off the low-boiling components at 125°C. The residue weighs 116.8g. Infrared detection shows that all the raw materials are converted into product C a F 2a+1 O(CF(CF 3 ) CF 2 O) b (CF 2 CF 2 CF 2 O) d CF 2 CF 2 CH 2 OH, yield 83.8%.