ASTM F 2579

1.1 This specification covers virgin amorphous poly(lactide) homopolymer and poly(lactide-co-glycolide) copolymer resins intended for use in surgical implants. The poly( dl -lactide) homopolymers covered by this specification are considered to be amorphous (that is, void of crystallinity) and are polymerized either from meso -lactide or from equimolar (racemic) combinations of d -lactide and l -lactide. The poly( dl -lactide-co-glycolide) copolymers covered by this specification are also considered to be amorphous and are co-polymerized from a combination of glycolide and either meso-lactide or racemic quantities of d -lactide and l -lactide, and typically possess nominal mole fractions that equal or exceed 50 % lactide. 1.2 Since poly(glycolide) is commonly abbreviated as PGA for poly(glycolic acid) and poly(lactide) is commonly abbreviated as PLA for poly(lactic acid), these polymers are commonly referred to as PGA, PLA, and PLA:PGA resins for the hydrolytic byproducts to which they respectively degrade. PLA is a term that carries no stereoisomeric specificity and therefore encompasses both the amorphous atactic/syndiotactic dl -lactide-based polymers and copolymers as well as the isotactic d -PLA and l -PLA moieties, each of which carries potential for crystallization. Therefore, specific reference to dl -PLA is essential to appropriately differentiate the amorphous atactic/syndiotactic dl -lactide-based polymers and copolymers covered by this specification. Thus, inclusion of stereoisomeric specificity within the lactic acid-based acronyms results in the following: poly( l -lactide) as P l LA for poly( l -lactic acid), poly( d -lactide) as P d LA for poly( d -lactic acid), and poly( dl -lactide) as P dl LA for poly( dl -lactic acid). 1.3 This specification covers virgin amorphous poly(lactide)-based resins able to be fully solvated at 30 ° C by either methylene chloride (dichloromethane) or chloroform (trichlorom ....(abbreviated)