PROCUREMENT OF PRIMARY REFERENCE MATERIALS

建议的工作涉及合成大量无添加剂的 聚四亚甲基(PTMO)、4，4-二苯基甲烷二异硫酸盐(MDI)和 聚氨基甲酸酯尿素(PUU)他们将研究整体和表面特性， 并制作成管子和板材。试点数量材料目标有 已被确认身份。提供了制造细节。无菌包装 将对聚氨酯尿素的样品进行表征，以确定 伽马辐射的影响，并评估与时间相关的地表变化 聚氨基甲酸乙酯尿素一级标准物质。这些研究的目的是 在确定由伽马辐射引起的退化效应时 灭菌技术。此外，调查人员还将解决 在应用程序之前的存储期间可能发生的与时间相关的更改。

The proposed work involves the synthesis of a lot of additive-free polytetramethylene (PTMO), 4, 4 diphenylmethane diisothionate (MDI), and polyurethaneurea (PUU). They will study bulk and surface characterization, and fabrication into tubes and sheets. Pilot quantity material goals have been identified. Fabrication details are provided. Sterile, packaged samples of the polyurethaneurea will be characterized to determine the effect of gamma radiation and to assess time dependent surface changes in the polyurethaneurea primary reference materials. These studies are aimed at determining the effect of degradation by the gamma irradiation sterilization technique. In addition, the investigators will also address time-dependent changes that might occur during storage prior to application.