脱模剂或称离型剂,是一种在将合成树脂、合成橡胶等成型之前,涂于模具上的处理加工助剂,防止合成树脂、合成橡胶等粘在模具上,并易于脱离模具,使模具表面无残留物质,加快生产进度。[1] 脱模剂是塑胶生产中使用的众多添加剂之一。[2]

脱模剂在成型表面和基材之间提供屏障,促进固化零件与模具的分离。如果没有这样的屏障,基材就会熔合到模具表面,导致清理困难并严重降低生产效率。即使使用脱模剂,不规则的应用或脱模剂选择不当等因素也可能对成品的品质和一致性产生巨大影响。[1]

应用领域

沥青

沥青脱模剂作为柴油和溶剂的替代品,通常用于清洁与热拌沥青混凝土相关的设备。

混凝土

在混凝土建筑行业中,脱模剂可防止新浇筑的混凝土粘附到成型表面,通常是胶合板、覆盖胶合板、

隔离脱模剂透过在成型表面和混凝土之间 形成物理膜或隔离层来防止黏附。

反应性脱模剂具有化学活性,透过脱模剂与新拌混凝土中的游离石灰之间的化学反应过程发挥作用。形成一层膜,防止黏附。由于这是一种化学反应过程,因此成型表面或混凝土上通常几乎没有残留物或未反应的产物,这提供了更清洁的过程。

食品加工

脱模剂用于帮助烘焙或烘烤后食品与烹饪容器分离。传统上使用脂肪面粉,但在工业食品加工中可能会使用其他化学物质。

金属铸造

脱模剂也可用于铝、铝合金、锌、锌合金、镁等金属的压铸或金属锻造制程。

在工业造纸中,脱模剂用于使纸张在加工设备中获得滑爽效果。

药品

将脱模剂(例如:硬脂酸镁)添加到粉末状和颗粒状的药物组合物中,以便在压片过程中用作脱模剂。

塑胶

是在模制和铸造中涂有脱模剂,以防止黏合剂黏合到塑胶表面。有助于将模具与被模制的材料分离并减少模制表面的缺陷。

橡皮

There are two types of release agents used in the molding of rubber products. Both are silicone based. The decision on which to use has to do with lubricity and release. Water-diluted silicone is used when you have rubber sliding over a hot mold (sheets or slugs). The silicone keeps the rubber from sticking to the mold but just as important it lubricates the rubber so it will slide over the hot mold as it is loaded. Diluted silicone typically has to be applied every cycle. Semi-permanent mold release builds a silicone matrix on the mold that becomes a barrier between the rubber and the metal surface of the mold. The matrix is created by the other ingredients in the semi-permanent mold release. Applications of semi-permanent mold release vary from every cycle to once daily applications depending on the compound being molded and the design and quality of the mold. Silicone-based rubber products, however, require a non-silicone based releasing agent.

参考文献

  1. ^ 1.0 1.1 Lammerting, Helmut, Release Agents, Ullmann's Encyclopedia of Industrial Chemistry, Weinheim: Wiley-VCH, 2005, doi:10.1002/14356007.a23_067 
  2. ^ Stevens, Malcolm P. Polymer Additives: III. Surface Property and Processing Modifiers. Journal of Chemical Education. 1993, 70 (9): 713. Bibcode:1993JChEd..70..713S. doi:10.1021/ed070p713.