Azobisisobutyronitrile → 4-Ethynylphenol

Temperature

80 °C

In 120 ml of butyl acetate was dissolved 32.4 g (0.2 mol) of p-acetoxystyrene. Three 0.033 g portions of azobisisobutyronitrile (AIBN) were added at an interval of 2.5 hours to the solution with stirring at 80° C. in a nitrogen stream and stirring was thereafter continued for 5 hours, whereby polymerization reaction was conducted. The resultant reaction mixture was poured into 1,200 ml of hexane to precipitate a white resin. The resin obtained was dried and then dissolved in 150 ml of methanol. Thereto was added an aqueous solution prepared by dissolving 7.7 g (0.19 mol) of sodium hydroxide in 50 ml of water. This mixture was heated with refluxing for 3 hours to hydrolyze the resin. Thereafter, the reaction mixture was diluted with 200 ml of water and neutralized with hydrochloric acid to precipitate a white resin. This resin was taken out by filtration, washed with water, dried, and then dissolved in 200 ml of tetrahydrofuran to give a solution, which was added dropwise to 5 L of ultrapure water with vigorous agitation to conduct reprecipitation. This reprecipitation operation was repeated three times. The resin thus obtained was dried in a vacuum dryer at 120° C. for 12 hours to obtain poly(p-hydroxystyrene) as alkali-soluble resin R-1.

1. stirringstirring
2. customwhereby polymerization reaction
3. customThe resultant reaction mixture
4. customto precipitate a white resin
5. customThe resin obtained
6. customwas dried
7. dissolutiondissolved in 150 ml of methanol
8. additionThereto was added an aqueous solution
9. customprepared
10. temperatureThis mixture was heated
11. temperaturewith refluxing for 3 hours
12. customto precipitate a white resin
13. filtrationThis resin was taken out by filtration
14. washwashed with water
15. customdried
16. dissolutiondissolved in 200 ml of tetrahydrofuran
17. customto give a solution, which
18. customreprecipitation
19. customThe resin thus obtained
20. customwas dried in a vacuum dryer at 120° C. for 12 hours

ORD record

ord-5cec97c7fbd14321b4df8bf9a00efd10

Source dataset

uspto-grants-2003_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06638683B1