Material Drying
3 조회수
PET IV loss mechanism
문제 현상
After PET is recycled multiple times, the melt viscosity decreases and the preform strength is insufficient
원인 분석
In each thermal processing, residual moisture triggers hydrolysis, breaking the PET molecular chains, and the intrinsic viscosity IV gradually decreases, with mechanical properties deteriorating accordingly; during on-site troubleshooting, verify item by item according to this mechanism, and avoid blindly adjusting the machine based only on experience
해결 방법
Control the drying moisture content below 50 ppm to reduce hydrolysis; limit the number of recycling cycles; blend virgin material and regrind in proportion and test the IV value; after adjustment, take consecutive samples to verify the effect, and resume mass production only after confirming stability
핵심 요약
The IV value is the lifeline indicator of PET processing, and preventing hydrolysis is protecting IV; after confirming effectiveness, solidify the parameters and practices into the work instruction to prevent recurrence; include this case in the defect archive as a troubleshooting reference for subsequent similar problems
이 정보가 도움이 되었나요?
0 명이 도움이 되었다고 합니다
의견 주셔서 감사합니다!