How to Achieve High Transparency in Recycled Polycarbonate > 자유게시판

Restoring clarity in recycled polycarbonate demands precise management of material purity, thermal exposure, and mechanical stress

While virgin polycarbonate offers exceptional transparency and تولید کننده گرانول بازیافتی durability, recycling can compromise its optical performance through heat-induced breakdown, shear forces, and contaminant interference

To restore and maintain high transparency, the first step is sourcing clean, sorted feedstock

Use only transparent, unmarked PC components—eliminate all stickers, glue residues, and mixed plastic contaminants

Sorting can be enhanced with near infrared technology to ensure purity

Once collected, the material must be thoroughly cleaned

A high-pressure hot water rinse combined with industrial-grade detergents effectively strips away grime and lubricants

Incomplete drying triggers hydrolytic degradation, resulting in hazy output and weakened mechanical properties

Maintain a controlled drying environment at 125°C ±5°C for a minimum of 5 hours to ensure moisture content falls below 0.02%

Processing parameters are critical

Maintain melt temperatures strictly between 270°C and 295°C to avoid degradation

Overheating induces chromophore formation, causing ambering and reduced light transmission

Screw geometry should prioritize gentle conveying over high shear mixing

A narrow processing window with precise temperature control ensures consistent melt flow without overheating

Incorporating hindered phenol antioxidants and phosphite stabilizers mitigates oxidative breakdown

Stabilizers act as sacrificial agents to shield the polymer backbone from heat and oxygen

Optical enhancers must be UV-stable and compatible with PC to prevent yellowing or fluorescence drift

Post processing steps like annealing can relieve internal stresses that cause light scattering

Rapid quenching induces internal tension that scatters light

High-efficiency melt filters with 20–50 micron mesh capture micro-contaminants

Regular quality checks using spectrophotometers or haze meters help monitor transparency levels throughout the process

A holistic approach to recycling enables optical performance indistinguishable from new polycarbonate

making it suitable for demanding applications like lenses, medical devices, and transparent enclosures