PROCUREMENT OF PRIMARY REFERENCE MATERIALS

本工作涉及大量无添加剂的合成， 聚四亚甲基（PTMO），4，4-二苯基甲烷二异硫代磺酸酯 (MDI)和聚脲（PUU）。 他们将大量学习， 表面表征和制造成管和板。 已确定试点的数量和材料目标。 制造 提供了细节。 无菌包装样品 将对聚脲进行表征，以确定 伽马辐射和评估时间依赖的表面变化， 聚脲一级标准物质。 这些研究 旨在确定伽马辐照降解的影响， 辐照灭菌技术 此外，调查人员 还将解决可能发生的与时间有关的变化， 应用前的存储。

The proposed work involves the synthesis of a lot of additivefree polytetramethylene (PTMO), 4, 4 diphenylmethane diisothionate (MDI), and polyurethaneurea (PUU). They will study bulk and surface characterization, and fabrication into tubes and sheets. Pilots quantity material goals have been identified. Fabrication details are provides. Sterile, packages 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 timedependent changes that might occur during storage prior to application.