Glycolide → Hydroxyacetic acid--2-hydroxypropanoic acid (1/1)

A PFA-made cylinder was charged with 100 g of recrystallized L-(-)-lactide and 100 g of glycolide, and the contents were dried at room temperature for about 30 minutes while introducing nitrogen gas. Then, 0.048 g of tin octanoate as a catalyst was added, and the contents were held at 130° C. for 20 hours while introducing nitrogen gas therein, thereby polymerizing the monomers. After completion of the polymerization, a bulk polymer taken out of the cylinder was ground into fine particles having a particle size of about 3 mm or smaller, and the fine particles were dried overnight at about 50° C. under reduced pressure of about 0.1 kPa to remove remaining monomers, thereby obtaining a glycolic acid/lactic acid copolymer [Polymer (P-C3)]. The same process was conducted repeatedly to prepare a necessary amount of Polymer (P-C3). The polymer thus obtained had a glass transition temperature, Tg of about 44° C. and was a noncrystalline amorphous substance.

1. customthe contents were dried at room temperature for about 30 minutes
2. additionwhile introducing nitrogen gas
3. additionThen, 0.048 g of tin octanoate as a catalyst was added
4. additionwhile introducing nitrogen gas
5. custompolymerizing the monomers
6. customAfter completion of the polymerization
7. customthe fine particles were dried overnight at about 50° C. under reduced pressure of about 0.1 kPa
8. customto remove

ORD record

ord-5958ba3f6a7842929054467883e6c635

Source dataset

uspto-grants-2000_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06159416