1、Designation:F257910Standard Specification forAmorphous Poly(lactide)and Poly(lactide-co-glycolide)Resins for Surgical Implants1This standard is issued under the fixed designation F2579;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,
2、the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers virgin amorphous poly(lactide)homopolymer and poly(lactide-co-glycolide)copolymer res
3、insintended for use in surgical implants.The poly(DL-lactide)homopolymers covered by this specification are considered tobe amorphous(that is,void of crystallinity)and are polymer-ized either from meso-lactide or from equimolar(racemic)combinations ofD-lactide andL-lactide.The poly(DL-lactide-co-gly
4、colide)copolymers covered by this specification are alsoconsidered to be amorphous and are co-polymerized from acombination of glycolide and either meso-lactide or racemicquantities ofD-lactide andL-lactide,and typically possessnominal mole fractions that equal or exceed 50%lactide.1.2 Since poly(gl
5、ycolide)is commonly abbreviated as PGAfor poly(glycolic acid)and poly(lactide)is commonly abbre-viated as PLA for poly(lactic acid),these polymers are com-monly referred to as PGA,PLA,and PLA:PGA resins for thehydrolytic byproducts to which they respectively degrade.PLAis a term that carries no ster
6、eoisomeric specificity and thereforeencompasses both the amorphous atactic/syndiotacticDL-lactide-based polymers and copolymers as well as the isotacticD-PLA andL-PLA moieties,each of which carries potential forcrystallization.Therefore,specific reference toDL-PLA isessential to appropriately differ
7、entiate the amorphous atactic/syndiotacticDL-lactide-based polymers and copolymers cov-ered by this specification.Thus,inclusion of stereoisomericspecificity within the lactic acid-based acronyms results in thefollowing:poly(L-lactide)as PLLA for poly(L-lactic acid),poly(D-lactide)as PDLA for poly(D
8、-lactic acid),and poly(DL-lactide)as PDLLA for poly(DL-lactic acid).1.3 Thisspecificationcoversvirginamorphouspoly(lactide)-based resins able to be fully solvated at 30C byeither methylene chloride(dichloromethane)or chloroform(trichloromethane).This specification is not applicable tolactide-based p
9、olymers or copolymers that possess isotacticpolymeric segments sufficient in size to carry potential forlactide-based crystallization,which are covered by Specifica-tion F1925 and typically possess nominal mole fractions thatequal or exceed 50%L-lactide.This specification is notapplicable to lactide
10、-co-glycolide copolymers that possessglycolide segments sufficient in size to deliver potential forglycolide-based crystallization,thereby requiring fluorinatedsolvents for complete dissolution under room temperatureconditions.This specification is specifically not applicable tolactide-co-glycolide
11、copolymers with glycolide mole fractionsgreater than or equal to 70%(65.3%in mass fraction),whichare covered by Specification F2313.This specification is notapplicable to block copolymers or to polymers or copolymerssynthesized from combinations ofD-lactide andL-lactide thatdiffer by more than 1.5 t
12、otal mole percent(1.5%of totalmoles).1.4 This specification addresses material characteristics ofboth poly(DL-lactide)and poly(DL-lactide-co-glycolide)resinsintended for use in surgical implants and does not apply topackaged and sterilized finished implants fabricated from thesematerials.1.5 As with
13、 any material,some characteristics may bealtered by processing techniques(such as molding,extrusion,machining,assembly,sterilization,and so forth)required forthe production of a specific part or device.Therefore,proper-ties of fabricated forms of this resin should be evaluatedindependently using app
14、ropriate test methods to assure safetyand efficacy.1.6 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.7 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility
15、 of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1This specification is under the jurisdiction of ASTM Committee F04 onMedical and Surgical Materials and Devices and is the direct responsibilit
16、y ofSubcommittee F04.11 on Polymeric Materials.Current edition approved Dec.1,2010.Published January 2011.Originallyapproved in 2006.Last previous edition approved in 2008 as F2579 08.DOI:10.1520/F2579-10.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 2.Referenced Documents2.1 ASTM Standards:2D1505 Test Method for Density of Plastics by the Density-Gradient TechniqueD2857 Practice for Dilute Solution Viscosity of PolymersD4603 Test M
