Designation:D4634−16StandardClassificationSystemandBasisforSpecificationforStyrene-MaleicAnhydrideMoldingandExtrusionMaterials(S/MA)1ThisstandardisissuedunderthefixeddesignationD4634;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope*1.1Thisclassificationsystemcoversstyrene-maleicanhy-dridematerialssuitableformoldingorextrusion.Thisclassi-ficationsystemdoesnotapplytoalloysorblendsofstyrene-maleicanhydridematerialswithnon-elastomericthermoplastics.Styrene-maleicanhydridematerials,beingthermoplastic,arereprocessableandrecyclable.Thisclassifi-cationsystemallowsfortheuseofthosematerialsprovidedthatallthespecificrequirementsofthisclassificationsystemaremet.1.2Thepropertiesincludedinthisstandardarethoserequiredtoidentifythecompositionscovered.Otherrequire-mentsnecessarytoidentifyparticularcharacteristicsimportanttospecializedapplicationsaretobespecifiedbyusingthesuffixesasgiveninSection5.1.3Thisclassificationsystemandsubsequentlinecallout(specification)areintendedtoprovidemeansofcallingoutpropertiesofplasticmaterialsusedinthefabricationofenditemsorparts.Itisnotintendedfortheselectionofmaterials.Materialsshouldbeselectedbythosehavingexpertiseintheplasticsfieldaftercarefulconsiderationofthedesignandtheperformancerequiredofthepart,theenvironmenttowhichitwillbeexposed,thefabricationprocesstobeemployed,costsinvolved,andtheinherentpropertiesofthematerialotherthanthosecoveredbythisclassificationsystem.1.4ThevaluesstatedinSIunitsaretoberegardedasthestandard.1.5Thefollowingprecautionarycaveatpertainsonlytothetestmethodsportion,Section11,ofthisclassificationsystem.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoesta...
