Any of various resins,widely varying in flexibility,used in tough chemical - resistant coatings,adhesives,and foams.

 
  • 聚氨基甲酸乙酯;聚氨酯一種在韌性上差別很大的樹(shù)脂,用于堅固的抗化學(xué)物質(zhì)涂面、黏合劑和泡沫中
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