phthalate etc various additives can also be included in the formulation to improve the performance further known lubricants can be included such as calcium stearate or other salts of fatty acids calcium stearoyl lactylate sodium stearoyl lactylate a bioabsorbable polyester carbonate salt or a bioabsorbable polyester salt such as str2 wherein m is an alkali metal for example sodium an alkaline earth for example calcium or magnesium or hydrogen or a combination of these the bioabsorbable polyester salts of formulas i and ii are discloed respectively in u s pat no 4 010 196 with the proviso as taught by this patent that m is not calcium and great britain pat no 1 207 588 these patents are incorporated herein by reference finally a water soluble lubricant such as poly alkylene oxide can be added the random copolymer of this invention is not soluble in body fluids the copolymer therefore will not be washed off by the first pass of a coated suture through tissue also the copolymer can retain its lubricant properties while wet poly glycolide co trimethylene carbonate s are bioabsorbable materials they offer good biocompatibility and are specially useful as coatings or coating binders for bioabsorbable multifilament sutures when used as coating materials glycolide trimethylene carbonate random copolymers improve the knot run down performance of multifilament sutures the polymers can also be used as binders to hold lubricants in place on the surface of a suture in order.