脫模劑或稱離型劑,是一種在將合成樹脂、合成橡膠等成型之前,塗於模具上的處理加工助劑,防止合成樹脂、合成橡膠等粘在模具上,並易於脫離模具,使模具表面無殘留物質,加快生產進度。[1] 脫模劑是塑膠生產中使用的眾多添加劑之一。[2]

脫模劑在成型表面和基材之間提供屏障,促進固化零件與模具的分離。如果沒有這樣的屏障,基材就會熔合到模具表面,導致清理困難並嚴重降低生產效率。即使使用脫模劑,不規則的應用或脫模劑選擇不當等因素也可能對成品的品質和一致性產生巨大影響。[1]

應用領域

瀝青

瀝青脫模劑作為柴油和溶劑的替代品,通常用於清潔與熱拌瀝青混凝土相關的設備。

混凝土

在混凝土建築行業中,脫模劑可防止新澆築的混凝土粘附到成型表面,通常是膠合板、覆蓋膠合板、

隔離脫模劑透過在成型表面和混凝土之間 形成物理膜或隔離層來防止黏附。

反應性脫模劑具有化學活性,透過脫模劑與新拌混凝土中的遊離石灰之間的化學反應過程發揮作用。形成一層膜,防止黏附。由於這是一種化學反應過程,因此成型表面或混凝土上通常幾乎沒有殘留物或未反應的產物,這提供了更清潔的過程。

食品加工

脫模劑用於幫助烘焙或烘烤後食品與烹飪容器分離。傳統上使用脂肪麵粉,但在工業食品加工中可能會使用其他化學物質。

金屬鑄造

脫模劑也可用於鋁、鋁合金、鋅、鋅合金、鎂等金屬的壓鑄或金屬鍛造製程。

在工業造紙中,脫模劑用於使紙張在加工設備中獲得滑爽效果。

藥品

將脫模劑(例如:硬脂酸鎂)添加到粉末狀和顆粒狀的藥物組合物中,以便在壓片過程中用作脫模劑。

塑膠

是在模製和鑄造中塗有脫模劑,以防止黏合劑黏合到塑膠表面。有助於將模具與被模製的材料分離並減少模製表面的缺陷。

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.

參考文獻

  1. ^ 移至: 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.