POM聚甲醛TheUnitedStatesdupont美国杜邦POM100BK602100AF100AL100B100KM100KMBK402100P100PBK602100PNC美国杜邦POM的其它级别高流动级***级挤出级押出级食品级脱模级阻燃级阻燃增强级阻燃耐高温级增强级)