Polymerization of Glycolic Acid

Poly(glycolic acid) (PGA) is the simplest linear aliphatic polyester. Both PGA and the copol)oner polyCglycolic acid - co - lactic acid) (PGA/PL) are used as degradable and absorbable sutures. 

X - Number of units of lactic acid Y - Number of units of giycolic acid 

Polygalactin 910 is a copolymer of glycolide and lactide, obtained from glycolic and lactic acid in 9 1 ratio. The multi-fiber threads, called Victyl or Pohsorb, are coated, transparent, or dyed purple. For Vicryl Rapid threads a material with smaller relative molecular mass is used, and as a result is absorbed more rapidly. 

Mexon is a synthetic single-fiber thread with slow absorption characteristics, made of a copolymer of glycolic acid and trimethyl carbonate. Three weeks after implantation it retains about 55% of its initial resistance complete absorption takes place after 26-30 weeks. The products of hydrolytic thread decomposition are carbon dioxide, -hydroxybutyric acid, and glycolic acid. 

Monocryl (Poliglecaprone 25) is a glycolide and -caprolactone copolymer. The thread is nontoxic, but causes a delicate reaction during absorption, which takes place in vivo by way of hydrolysis. 

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