{"id":"wpc-tech100-article-097-en","slug":"regrind-particle-size-control-before-recompounding","locale":"en","url":"https://woodplasticcomposite.net/guides/regrind-particle-size-control-before-recompounding/","title":"Regrind particle-size control before recompounding","answer":"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.","author":"NFC & WPC Knowledge Reference","faqIds":["wpc-tech100-faq-097-en"],"tagIds":[],"noindex":false,"related":["wpc-tech100-article-098-en"],"version":1,"modified":"2026-10-15","reviewer":"","sections":[{"id":"technical-context","text":"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.","heading":"Technical context","references":[],"url":"https://woodplasticcomposite.net/guides/regrind-particle-size-control-before-recompounding/#technical-context"},{"id":"verification-plan","text":"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.","heading":"What to measure and document","references":[],"url":"https://woodplasticcomposite.net/guides/regrind-particle-size-control-before-recompounding/#verification-plan"},{"id":"practical-decision","text":"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.","heading":"Implications for development and specification","references":[],"url":"https://woodplasticcomposite.net/guides/regrind-particle-size-control-before-recompounding/#practical-decision"},{"id":"reading-scope","text":"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.","heading":"Related reading and evidence limits","references":[1],"url":"https://woodplasticcomposite.net/guides/regrind-particle-size-control-before-recompounding/#reading-scope"}],"seoTitle":"Regrind particle-size control before recompounding | WPC Reference","topicIds":[],"published":"2026-10-15","tableText":"Review step | Evidence to retain\nMaterial and geometry | Exact specimen or product identity\nVerification | Method, conditions and individual observations\nDecision | Approved scope and documented limitations","takeaways":"Grinding conditions and the source components influence what enters the next process.\nRecord source identity, grinding method and a suitable particle-size check.\nSet reuse boundaries through qualification rather than an arbitrary universal percentage.","aiAssisted":true,"categoryId":"wpc-tech100-category-4","reviewedAt":"","change_note":"New focused technical draft; not a product certification or production recipe.","description":"Regrind is a manufactured feedstock with its own size distribution and handling behaviour.","heroImageId":"","referenceIds":["wpc-tech100-ref-reprocessing"],"review_status":"AI-assisted English editorial draft. Human technical review has not been recorded.","table_caption":"Evidence checklist for regrind particle-size control before recompounding","seoDescription":"Regrind is a manufactured feedstock with its own size distribution and handling behaviour.","translationGroup":"wpc-tech100-097-2026","references":[{"url":"https://doi.org/10.3390/polym18121509","type":"web","title":"Reprocessing PVC-based wood-plastic composites","noindex":false,"accessed":"2026-10-14","seoTitle":"Reprocessing PVC-based wood-plastic composites","publisher":"Polymers","description":"Related reading; scope and limitations are identified in each article.","seoDescription":"Related reading; scope and limitations are identified in each article."}],"faqs":[{"question":"What evidence is needed for regrind particle-size control before recompounding?","answer":"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."}]}