At a glance
Regrind is a manufactured feedstock with its own size distribution and handling behaviour. It should not be described only by the percentage added to a WPC recipe.
Key points
- Grinding conditions and the source components influence what enters the next process.
- Record source identity, grinding method and a suitable particle-size check.
- Set reuse boundaries through qualification rather than an arbitrary universal percentage.
Technical context #
Grinding conditions and the source components influence what enters the next process. Fine material and larger fragments may feed differently. A blend containing the same nominal regrind fraction can therefore behave differently between batches.
What to measure and document #
Record source identity, grinding method and a suitable particle-size check. Keep contaminants and incompatible product variants out of the approved stream. Compare feeding stability and finished-product results when changing the regrind preparation process.
Implications for development and specification #
Set reuse boundaries through qualification rather than an arbitrary universal percentage. Internal production scrap and recovered outdoor products are different feedstock situations. Traceability should distinguish them so a recycled-content claim does not conceal uncontrolled material history.
Related reading and evidence limits #
A reprocessing study of a specific PVC-based WPC; other matrices require their own evidence. Use the linked work as related reading. The practical checks above are editorial recommendations, not reported test results or a substitute for product qualification.
Evidence checklist for regrind particle-size control before recompounding
| Review step | Evidence to retain |
|---|---|
| Material and geometry | Exact specimen or product identity |
| Verification | Method, conditions and individual observations |
| Decision | Approved scope and documented limitations |
Common questions
What evidence is needed for regrind particle-size control before recompounding?
Record source identity, grinding method and a suitable particle-size check. Keep contaminants and incompatible product variants out of the approved stream. Compare feeding stability and finished-product results when changing the regrind preparation process.
Question permalink ↗Sources & further reading
- Reprocessing PVC-based wood-plastic composites ↗Polymers · web · 2026-10-14
Cite this page
J. A. Gill. “Regrind particle-size control before recompounding” Version 1. Updated 2026-10-15. https://woodplasticcomposite.net/guides/regrind-particle-size-control-before-recompounding/
Author profile
Author: J. A. Gill
WPC and natural-fibre composite specialist · Innovator, inventor, product designer and entrepreneur
New focused technical draft; not a product certification or production recipe.
General material information is not product certification or project-specific engineering advice.
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