ASTM F 2579

1.1 This specification covers virgin poly(lactide) and poly(lactide-co-glycolide) resins able to be fully solvated at 30°C by either methylene chloride (dichloromethane) or chloroform (trichloromethane). The poly(d,l-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(d,l-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 enantiomeric specificity and therefore also encompasses the isotactic d-PLA and l-PLA moieties, each of which carries potential for crystallization. Therefore, specific reference to d,l-PLA is essential to appropriately differentiate the amorphous atactic/syndiotactic d,l-lactide based polymers and copolymers covered by this specification. 1.3 This specification is not applicable to lactide based polymers or copolymers that possess isotactic polymeric segments sufficient in size to deliver potential for lactide based crystallization. This specification is not applicable to lactide-co-glycolide copolymers that possess glycolide segments sufficient in size to deliver potential for glycolide based crystallization, thereby requiring fluorinated solvents for complete dissolution under room temperature conditions. This specification is specifically not ap ....(abbreviated)