High -Temp Materials
Robin Brain
November 22, 2008
The processing of materials like Peek Polyetheretherketone can easily make a molder tensed and send nervous tremors through his body. A molder is a person who learns the art of crafting of PP or PE closures along with their melting temperatures and cold moulds. Peek is a thermoplastic resin which can be molded safely by applying a few precautions. Peek is considered to be the most demandable and chief performing thermoplastics available in the market these days. The properties of this thermoplastic more than justify the tribulations and trials a person may encounter with its processing. Peek is a semi-crystalline thermoplastic which is linearly aromatic. It has an excellent wearing properties along with chemical and hydrolysis resistance. This thermoplastic has a very low smoke toxicity and is an excellent conductor of electricity. These properties add to its advantages which a person can use in many fields.
The processing of Peek is done at a very high melting temperature of 720o F. the press barrel and the controls must be capable of doing this, then only the processing of this thermoplastic can be done successfully. Many of the molding machines support software which is capable of handling high temperatures and it is recommended to select the ceramic high temperature heat bands if it is possible in the molding machine. Always a special barrel and screw are not required for the molding purposes but they should be considered while handling filled Peek resins. Typically, sliding ring non-return valves are used and ball checks or shut off nozzles are not generally recommended. A mould with high temperature is the key of the crystallinity in the Peek parts. The hotter is the mold the higher is the crystallinity of the Peek resins.
The purging of Peek allows a person to see the crystallization of translucent parts of the Peek resins turn into solid colored parts which are in pure crystalline form. If the temperature of the mould is not that hot, then the Peek resins would have partial translucency and the state of the final product will not be a pure crystalline and would be compromised. Generally the temperature of the mould should be around 350o -450o F. to maintain this level of temperature, oil or cartridge heat are required. Oil is the preferred option for this as there are complex part in the system which need more accurate controlling of the temperature.
The processing of Peek is done at a very high melting temperature of 720o F. the press barrel and the controls must be capable of doing this, then only the processing of this thermoplastic can be done successfully. Many of the molding machines support software which is capable of handling high temperatures and it is recommended to select the ceramic high temperature heat bands if it is possible in the molding machine. Always a special barrel and screw are not required for the molding purposes but they should be considered while handling filled Peek resins. Typically, sliding ring non-return valves are used and ball checks or shut off nozzles are not generally recommended. A mould with high temperature is the key of the crystallinity in the Peek parts. The hotter is the mold the higher is the crystallinity of the Peek resins.
The purging of Peek allows a person to see the crystallization of translucent parts of the Peek resins turn into solid colored parts which are in pure crystalline form. If the temperature of the mould is not that hot, then the Peek resins would have partial translucency and the state of the final product will not be a pure crystalline and would be compromised. Generally the temperature of the mould should be around 350o -450o F. to maintain this level of temperature, oil or cartridge heat are required. Oil is the preferred option for this as there are complex part in the system which need more accurate controlling of the temperature.
To Get more information on Peek Polyetheretherketone and Arlon.