Daim ntawv thov: nylon engineering plastics raws li tus nqi loj, dav siv hauv tshuab, tsheb, khoom siv, khoom siv textile, khoom siv tshuaj, aviation, metallurgy thiab lwm yam haujlwm. Txhua qhov chaw ntawm lub neej kom dhau los ua cov khoom siv tsis tseem ceeb, xws li ua txhua yam ntawm cov kabmob, rub ...
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