Mold release agent is a functional material between the mold and the finished product. Mold release agents are chemically resistant and do not dissolve when contacted with the chemical constituents of different resins, especially styrene and amines. Mold release agent also has heat and stress properties, not easy to break down or wear; mold release agent is bonded to the workpiece is not transferred to be processed, without prejudice to painting or other secondary processing operations. Due to the rapid development of injection molding, extrusion, calendering, molding, laminating and other processes, the amount of mold release agent is also greatly increased.
The specific role principle of release agent
1. Polar chemical bond with the mold surface through the interaction to form a regenerative adsorption film;
Silicone bonds in polysiloxanes can be regarded as weak dipoles (Si + -O-). When the mold release agent spreads in the uniaxial orientation on the mold surface, the molecules adopt a unique stretching chain configuration.
3. The free surface is densely covered by alkyl, and the demoulding ability increases with the density of alkyl groups. However, when the alkyl group occupies a larger steric hindrance, the extension configuration is limited and the demoulding ability will be reduced.
4. Release agent molecular size and viscosity are also related to the release ability, molecular weight hours, good spreading, but poor heat resistance.
Release agent selection points
1. Mold release is excellent, the surface tension of spray mold release agent is between 17 ~ 23 N / m.
2. With heat resistance, heat does not occur carbonization decomposition.
3. Stable chemical properties, not with the molded product chemical reaction.
4. Does not affect the secondary processing of plastic properties.
5. Does not corrode the mold, does not pollute the products, odor and toxicity is small.
6. The appearance of smooth and beautiful.
7. Easy coating, high production efficiency.