脱膜剂的种类

◆ 脱模剂
  脱模剂是为防止成型的复合材料制品在模具上粘着,而在制品与模具之间施加一类隔离膜,以便制品很容易从模具中脱出,同时保证制品表面质量和模具完好无损。常用的脱模剂主要有以下几类:
  (1)按脱模剂的使用方式不同有外脱模剂及内脱模剂之分。外脱模剂是直接将脱模剂涂敷在模具上;内脱模剂是一些熔点比普通模制温度稍低的化合物,在加热成型工艺中将其加入树脂中,它与液态树脂相容,但与固化树脂不相容,在一定加工温度条件下,从树脂基体渗出,在模具和制品之间形成一层隔离膜。
  (2)按脱模剂的状态不同有薄膜型(主要有聚酯、聚乙烯、聚氯乙烯、玻璃纸、氟塑料薄膜)、溶液型(主要有烃类、醇类、羧酸及羧酸酯、羧酸的金属盐、酮、酰胺和卤代烃)、膏状及蜡状(包括硅酯、HK-50耐热油膏、汽缸油、汽油与沥青的溶液及蜡型)脱模剂。基中蜡型脱模剂是应用最广泛的一类脱模剂,价格便宜、使用方便、无毒、脱模效果好,缺点是会使制品表面沾油污,影响表面上漆,漏涂时会使脱模困难。对于成型形状复杂的大型制品常与溶液型脱模剂复合使用。
  (3)按脱模剂的组合情况有单一型和复合型脱模剂(包括组分复合和使用方式上的复合)。
  (4)按脱模剂的使用温度有常温型和高温型脱模剂,如常温蜡、高温蜡及硬脂酸盐类。
  (5)按其化学组成有无机脱模剂(如滑石粉、高岭土等)和有机脱模剂。
  (6)按其复用次数有一次性脱模剂和多次性脱模剂。

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