Views: 24 Author: Site Editor Publish Time: 2019-02-17 Origin: Site
The fluidity of PMMA sheets is worse than PS and ABS. Melt viscosity is sensitive to temperature changes. During the forming process, the melt viscosity is mainly affected by the injection temperature. Polymethyl methacrylate is an amorphous polymer having a melting temperature of more than 160 ° C and a decomposition temperature of 2 70 ° C.
The PMMA sheet has a water absorption of 0.3 to 0.4, and the injection molding temperature must be less than 0.1%, usually 0.04. The presence of water causes bubbles, gas lines, and reduced transparency in the melt. Good work. Drying temperature 80~90 °C, drying time is more than 3h.
Recycled materials can be used 100% in some cases. The actual quantity depends on the quality requirements, usually more than 30%. The recycled materials must avoid contamination, otherwise it will affect the transparency and properties of the finished product.
It can be measured by air jet method. According to the information provided by the suppliers, the range ranges from 210 to 270.
It can be injected quickly, but in order to avoid high internal stress, multi-stage injection should be used, such as slow-fast-slow, injection thick parts, slow speed and so on.
