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This specification covers the material characteristics of virgin poly(glycolide) and poly(glycolide-co-lactide) resins with mole fractions within the specified range used in surgical implants. This does not cover packaged and sterilized finished implants fabricated from the same materials. Since some characteristics may be altered by processing techniques when used to produces a specific part or device, properties of fabricated forms of the resins should be evaluated independently using appropriate test methods. The identity of the poly(glycolide) homopolymer, poly(glycolide-co-lactide) copolymer, and poly(glycolide-co-lactide) polymer must be confirmed through nuclear magnetic resonance (NMR).1.1 This specification covers both virgin poly(glycolide) homopolymer and poly(glycolide-co-lactide) copolymer resins intended for use in surgical implants. The poly(glycolide-colactide) copolymers covered by this specification possess nominal mole fractions greater than or equal to 70 % glycolide (65.3 % in mass fraction). This specification is also 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.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.1.3 This specification is specifically not applicable to amorphous poly(lactide-co-glycolide) or poly(lactide)-based resins able to be fully solvated at 30°C by either methylene chloride (dichloromethane) or chloroform (trichloromethane), which are covered in Specification F2579 and typically possess molar glycolide levels of ~50 % or less. This specification is not applicable to lactide-based polymers or copolymers that possess isotactic polymeric segments sufficient in size to carry potential for lactide-based crystallization, which are covered by Specification F1925 and typically possess nominal mole fractions that equal or exceed 50 % l-lactide.1.4 This specification addresses material characteristics of both virgin poly(glycolide) and poly(>70 % glycolide-co-lactide) resins intended for use in surgical implants and does not apply to packaged and sterilized finished implants fabricated from these materials.1.5 As with any material, some characteristics may be altered by processing techniques (such as molding, extrusion, machining, assembly, sterilization, and so forth) required for the production of a specific part or device. Therefore, properties of fabricated forms of this resin should be evaluated independently using appropriate test methods to assure safety and efficacy.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This specification covers quenched and tempered high-strength low-alloy structural steel plates for welded, riveted, or bolted construction. It is intended primarily for use in welded bridges and buildings where savings in weight, added durability, and good notch toughness are important. When properly exposed to the atmosphere, this steel can be used bare (unpainted) for many applications. The steel shall conform on heat and product analysis to the chemical composition requirements prescribed for carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, copper, and vanadium. Tensile test requirements shall include: yield strength, tensile strength, and elongation. The requirements for manufacturing, heat treatment, and longitudinal Charpy V-notch impact testing are given as well.1.1 This specification covers quenched and tempered high-strength low-alloy structural steel plates for welded, riveted, or bolted construction. It is intended primarily for use in welded bridges and buildings where savings in weight, added durability, and good notch toughness are important. The atmospheric corrosion resistance of this steel in most environments is substantially better than that of carbon structural steels with or without copper addition (see Note 1). When properly exposed to the atmosphere, this steel can be used bare (unpainted) for many applications. Welding technique is of fundamental importance, and it is presupposed that the welding procedure will be suitable for the steel and the intended service. This specification is limited to material up to 4 in. [100 mm], inclusive, in thickness. See Appendix X3 of Specification A 6/A 6M for information on weldability. Note 1—For methods of estimating the atmospheric corrosion resistance of low-alloy steels, see Guide G 101.1.2 Plates produced under this specification are impact tested at a temperature not higher than 50°F [10°C].1.3 The values stated in inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each item are not exact equivalents. Therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with this specification.

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定价: 1044元 / 折扣价: 888 加购物车

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