Polymers have a propensity to stick more or less into cavities of moulds. Some drawbacks are obvious, particularly the impossibility to automatically demould, which disturbs processing and increases wastes, labour and cost. Other effects are more hidden such as the lack of accuracy of precision details, the initiation of cracks or tears, the fouling needing more frequent cleaning of the moulds…
To obviate these difficulties it is possible to use release agents whose choice is a delicate exercise taking into account the nature of the compound, the complexity of the part to be produced, the nature of the mould material, the processing parameters…
Apart from corrosion coming with specific polymers:
* All compounds contain oligomers, organic derivatives, mineral fillers…
* Walls of moulds are not perfectly smooth and clean
* Parts comprise grooves, folds, small cavities or holes etc. keeping the compound…
All these features lead to chemical, physical and/or mechanical adhesion. If this one is high enough.
* Light and soft parts cannot release and disturb processing increasing costs, wastes and decreasing productivity.