The cause of color-changing of unplasticized polyvinyl chloride(PVC-U) profile in the process of window-making and storage and its prevention are presented.
介绍硬质聚氯乙烯（ PVC U）异型材在储存、成窗的过程中产生变色的原因及其预防措施；
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Plastics piping systems for buried and above-ground drainage and sewerage under pressure - Unplasticized poly (vinyl chloride) (PVC-U) - Part 1: specifications for piping components and the system.