Material Analysis
2 views
Quality fluctuation caused by regrind use of high impact polystyrene
Problem Phenomenon
After using regrind, product quality fluctuates, color changes, strength decreases, or black specks appear.
Cause Analysis
(1) Regrind repeatedly processed many times, molecular weight gradually decreases
(2) Different materials or impurities mixed into the regrind
(3) Regrind pelletizing temperature too high, material partially degrades
(4) Uneven regrind particle size, unstable feeding
(5) Regrind ratio too high or inconsistent
Solution
(1) Control regrind ratio not exceeding 15-20%
(2) Regrind used no more than twice repeatedly
(3) Regrind stored by classification, different materials must not be mixed
(4) Regrind pelletizing temperature controlled at the lower value within the 180-240°C range
(5) Regrind sieved after crushing
Key Takeaway
Regrind use needs to control ratio and number of times; classified management is key.
Was this helpful?
0 people found this helpful
Thank you for your feedback!