What are the causes and treatment methods of plastic mold sticking?

What are the causes and treatment methods of plastic mold sticking?

The reasons for plastic mold sticking can be summarized into the following 7 aspects, the following to introduce the plastic mold sticking causes and treatment methods in detail:

1, mold surface rough:
(1) Cause: scratches, grooves or bumps on the surface of the mold will cause plastic parts to stick to the mold in these places.
(2) Treatment method: Improve the finish of the mold surface during processing, or apply anti-stick coating on the surface of the mold, such as silicone or PTFE.

2, mold temperature is too high:
(1) Reason: too high mold temperature will cause the plastic to produce excessive friction and adhesion on the mold surface, resulting in sticky mold.
(2) Treatment method: Reasonable control of mold temperature, generally can be controlled by cooling system.

3. Improper use of release agent:
(1) Reason: If the release agent used cannot effectively reduce the adhesion between the plastic and the mold, it will lead to sticky molds.
(2) Treatment method: Select release agents suitable for specific molds and plastic materials, such as silicone, PTFE, etc.

4, plastic material problems:
(1) Reason: Some plastic materials naturally have a higher risk of sticking. For example, some high polymer materials have high elastic modulus and viscoelasticity, which are easy to produce viscous mold phenomenon during demoulding.
(2) Treatment method: Try to change the plastic material, or add anti-adhesion agents to the material.

5, mold design problems:
(1) Reason: If some parts of the mold, such as side walls or holes, are not designed to take into account the shrinkage and expansion of the plastic parts, it may cause the plastic parts to produce sticky molds in these areas.
(2) Treatment method: Redesign the mold and take it into consideration to avoid such problems.

6, plasticizing process problems:
(1) Reason: If the plasticizing process is not set properly, such as temperature, pressure, time and other parameters are not set accurately, it will lead to excessive viscosity of the plastic in the mold, resulting in a sticky mold.
(2) Treatment method: precise control of plasticizing process parameters, such as temperature, pressure, time, etc.

7, injection process problems:
(1) Reason: If in the injection process, the injection speed is too fast or the injection pressure is too large, it will cause the plastic to generate too much heat in the mold, so that the plastic parts are bonded with the mold after cooling.
(2) Treatment method: Reasonable control of the injection molding process, such as reducing the injection speed or injection pressure, to avoid excessive heat generation.

To sum up, preventing plastic mold sticking needs to be considered and optimized from many aspects such as mold design, material selection, release agent use, mold temperature control, plasticizing process and injection molding process. In actual production, the appropriate treatment method should be selected according to the specific situation.