| 											PC materials
PC (Polycarbonate) 											Typical Applications
Electronic and business equipment (computer parts, connectors, etc.),   appliances (food processors, refrigerator drawers, etc.), transportation (head   lights, tail lights, instrument panels, etc.). 											Injection Molding Processing Conditions
													
     
	
     | 	Drying
 | PC grades are hygroscopic and pre-drying is important. Recommended drying   conditions are 100 - 120 C (212 - 248 F) for 3 to 4 hours. Moisture content must   be less than 0.02% prior to processing. |  
	
     | 	Melt Temperature
 | 260 - 340 C (500 - 644 F); higher range for low MFR grades and   vice-versa |  
	
     | 	Mold Temperature
 | 70 - 120 C (158 - 248 F); higher range for low MFR grades and   vice-versa |  
	
     | 	Material Injection Pressure
 | As high as possible for rapid molding |  
	
     | 	Injection Speed
 | Slow injection speeds when small or edge gates are used; high speeds for   other types of gates |  											Chemical and Physical Properties
Polycarbonate is a polyester of carbonic acid. All general-purpose   polycarbonates are based on bisphenol A. The bisphenol A component of the   molecule contributes to the high glass transition temperature (150 C / 302 F).   The rotational mobility of the carbonyl group within the molecule contributes to   the high ductility and toughness of the material. PC is an amorphous engineering material with exceptionally good impact   strength, heat resistance, clarity, sterilizability, flame retardancy, and stain   resistance. The notched Izod impact strength of PC is very high and mold   shrinkage is low and consistent (.1 -.2 mm/mm). High molecular weight PCs (which translate to low melt flow rate) have higher   mechanical properties, but processibility of such grades becomes difficult. The   type of PC chosen for a particular application should be based on the desired   criteria (for high impact properties, use a low-MFR PC; conversely, for optimal   processibility, use a high-MFR PC). The melt viscosities are typically Newtonian up to shear rates of 1000 1/s   and decrease beyond that. The Heat Deflection Temperature Under Load is   typically between 130 -140 C (266 - 284 F) and the Vicat Softening Point is   typically around 155 C (311 F). 
  
  
  
      
  
      
  
  
  
  
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