How to Optimize Barrel Temperature Profiling for Recycled Polymers > 자유게시판

Tailoring barrel thermal settings for recycled polymers demands careful consideration due to their frequent contamination, chain scission, and variable feedstock quality

The first step is to understand اکسیر پلیمر the thermal history of the recycled material

Each reprocessing cycle tends to break polymer chains, decreasing molecular weight and changing how the material responds to heat

Consequently, these materials typically exhibit reduced melting points and heightened susceptibility to thermal breakdown

Prioritize detailed physical and thermal profiling of the recycled batch

Employ DSC and MFI analyses to map out the thermal transition points and flow behavior

Your temperature zones must be calibrated based on this empirical evidence

Avoid using the same profiles you would for virgin material, as this can lead to thermal degradation, discoloration, or inconsistent flow

Establish a smooth thermal gradient across all barrel sections

Maintain the feed zone temperature slightly above Tg to ensure smooth material intake without clumping

The compression zone should rise steadily to ensure complete melting without excessive shear heat

Set the metering zone temperature to stay safely beneath the onset of thermal breakdown

Track real-time melt viscosity via an accurate inline sensor

This real-time feedback is critical because recycled materials can vary batch to batch

Overheating? Dial back rear zone temps and slow the screw to minimize friction

If the melt is too cool, increase the front zone temperatures slightly and consider increasing screw RPM to generate more shear, but only if the material can tolerate it

Reduce the time material spends in the barrel

Prolonged heat exposure accelerates breakdown—streamline cycles and eliminate extended dwell times

Clean the barrel and screw regularly to remove degraded material that can act as a nucleation point for further degradation

If feasible, mix in 5–15% virgin resin to stabilize processing

This can improve process stability and reduce the need for aggressive temperature adjustments

Run pilot trials and record the impact of every thermal adjustment on finish, hue, and strength

Over time, you’ll build a reliable profile tailored to your specific recycled stream