Meaning
A high-performance amorphous thermoplastic polymer featuring carbon groups linked to bisphenol A offers exceptional optical clarity, impact resistance, and high heat distortion temperatures. Manufacturers utilize polycarbonate to produce shatterproof lenses, protective face shields, and durable housings for medical devices. This polymer resists high-energy impacts that would shatter other transparent plastics.
Optical Clarity
Light transmission rates comparable to glass allow the material to replace silica in many critical applications. When a manufacturer designs safety goggles or instrument covers, polycarbonate provides both high visibility and superior impact protection. The resin does not yellow quickly under normal indoor lighting conditions.
Additives are often incorporated to protect the material from ultraviolet radiation during outdoor exposure.
Impact Strength
Toughness remains high across a wide temperature range from sub-zero conditions up to the boiling point of water. Industrial helmets and bullet-resistant windows utilize polycarbonate for its ability to deform elastically under sudden load rather than cracking. This ductile behavior during sudden impact prevents catastrophic failures in protective gear.
Processors must avoid blending different grades to maintain this high impact resistance.
Drying Requirement
Moisture removal before processing is mandatory to prevent aesthetic and structural degradation. If a operator processes polycarbonate that contains trace moisture, the water causes hydrolytic degradation at melt temperatures. This cleavage of polymer chains reduces the mechanical strength and creates fine silver streaks on the molded surface.
Standard procedures dictate drying the resin in a desiccant dryer to a very low moisture level before mold injection. This pre-treatment ensures that the optical and mechanical specifications of the finished lens are met.
