NatuClothes

REPREVE Recycled Polyester: Properties, Production, and Verified Sustainability Data

By FabricData Research Team Published:

REPREVE is a branded recycled polyester fiber produced by Unifi, Inc. (Greensboro, NC) since 2007, made primarily from post-consumer PET bottles via thermomechanical recycling. Chemically, REPREVE is identical to virgin polyester — both are polyethylene terephthalate (PET) with density approximately 1.38 g/cm³, melting point 250-260 °C, and moisture regain ~0.4%. Unifi’s 2023 peer-reviewed Life Cycle Assessment reports 42% lower greenhouse gas emissions for REPREVE filament yarn versus virgin filament, alongside 67% lower freshwater consumption and 66% lower fossil fuel depletion. Independent 2025 testing by Çukurova University and the Changing Markets Foundation (n=51 garments) found that mechanically recycled polyester sheds approximately 54.8% more microfibers per gram than virgin polyester. The sustainability picture is impact-category-dependent — strong on energy and carbon, contested on microfiber shedding.

The data below replaces marketing equivalencies with measured polymer values, peer-reviewed citations, and standardized test references. For the broader context of mechanical rPET versus virgin PET — including BPA residues, antimony, and price premium ranges — see the recycled polyester data overview.

What REPREVE Is (and What It Isn’t)

REPREVE is a brand of recycled polyester fiber, not a distinct fiber chemistry. The polymer is polyethylene terephthalate, abbreviated PET, with the repeating unit (C₁₀H₈O₄)ₙ. Every strand carries Unifi’s FiberPrint tracer — a proprietary additive blended at the resin stage that enables independent laboratories to verify REPREVE content in finished fabric.

What REPREVE is not:

  • Not “natural” or “plant-based.” PET is a synthetic petroleum-derived polymer regardless of feedstock. Recycled feedstock postpones disposal of an existing PET bottle but does not regenerate the polymer from biological inputs.
  • Not biodegradable (with one exception). PET fibers are not recognized by microorganisms that drive biodegradation; published estimates for synthetic-fiber landfill persistence range from 20 to 200+ years (industry textile-degradation reviews). Only REPREVE with CiCLO® — launched April 2025 — contains an additive intended to promote biodegradation in soil and marine environments.
  • Not “ocean plastic.” Only the REPREVE Our Ocean variant uses bottles collected within 50 km of coastline (per OceanCycle certification criteria). Standard REPREVE feedstock comes from curbside and municipal post-consumer bottle collection.
  • Not chemically distinct from virgin PET. The polymer chemistry is identical; the differences are at the molecular-weight level (lower intrinsic viscosity in mechanically recycled PET) and at the verification level (FiberPrint, U-TRUST, GRS).

The brand-versus-polymer distinction matters because every measurable performance property of REPREVE — tenacity, moisture regain, melting point, abrasion resistance — is governed by PET chemistry and the mechanical recycling process, not by the REPREVE label itself.

Polymer and Fiber-Level Properties

No top-ranking competitor for “REPREVE recycled polyester” publishes polymer-level specifications side by side with virgin PET. The values below come from primary textile science references and peer-reviewed recycling studies.

PropertyREPREVE (mechanical rPET)Virgin PETSource / standard
PolymerPET (C₁₀H₈O₄)ₙPET (C₁₀H₈O₄)ₙUnifi product spec
ISO 2076:2021 classSyntheticSyntheticISO 2076:2021
Density (g/cm³)~1.38~1.38Welle 2011
Melting point (°C)250-260250-260Welle 2011
Glass transition Tg (°C)67-7570-80Awaja & Pavel 2005
Intrinsic viscosity (dL/g)0.65-0.72 (post-recycle)0.78-0.85Welle 2011
Moisture regain (%)~0.4~0.4ASTM D2654 (typical)
Tenacity, filament (cN/dtex)4.0-5.55.0-6.5Akyildiz et al. 2024
Tenacity, staple (cN/dtex)3.5-5.04.0-5.5Industry typical
Elongation at break (%)20-3520-35ISO 5079 (typical)
Typical filament denier50D-300D (1-3 dpf)50D-300DUnifi product spec
Approx. filament diameter (μm)~10-15 (at 1-3 dpf)~10-15Industry typical

The intrinsic viscosity (IV) reduction in row five is the technical core of every downstream performance difference. Welle (2011) measured IV drops from approximately 0.80 dL/g in virgin PET to 0.65-0.72 dL/g after mechanical recycling. Lower IV means shorter polymer chains, which translates to lower crystallinity and 5-15% lower tenacity in unblended mechanically recycled fiber. This is why mill specifications often blend mechanical rPET with virgin PET to recover strength — and it is the polymer-level reason recycled polyester is not, contrary to some marketing claims, “just as strong as virgin polyester” without qualification.

The moisture regain figure — 0.4% per ASTM D2654 — is identical for REPREVE and virgin PET because regain is governed by the polymer’s polar-group density, not by feedstock. This is the same number that drives polyester’s behavior in the cotton-versus-polyester breathability comparison, where cotton (regain 7-8.5%) absorbs moisture into the fiber while polyester transports liquid via capillary action between fibers.

How REPREVE Is Produced

The standard REPREVE production pathway is thermomechanical recycling — a four-step process that re-melts existing PET rather than chemically depolymerizing it.

  1. Collection. Post-consumer PET bottles enter Unifi’s Yadkinville, NC processing center primarily through municipal recycling streams. Industry reports estimate the facility receives approximately 130 million pounds of recycled material annually.
  2. Wash, sort, shred. Bottles are washed (label adhesive and residual contents removed), sorted by polymer type (PET separated from HDPE, LDPE, PP), and shredded into flakes. Particle size at this stage is typically 6-10 mm.
  3. Melt and chip. Flakes are dried, melted, and re-extruded into pellets (“chip” or “resin”). FiberPrint tracer is added to chip at this stage — every gram of REPREVE thereafter carries the marker.
  4. Spin into fiber. Chip is melted again and extruded through spinneret dies into continuous filament yarn or cut to staple. Filament diameter is determined by spinneret hole size and post-extrusion draw ratio; standard REPREVE is sold in 50D-300D filament with 1-3 denier per filament (dpf).

Each thermal cycle in steps 3-4 produces additional molecular-weight reduction. This is the core mechanical limitation that distinguishes thermomechanical recycling (which Unifi uses for standard REPREVE) from chemical recycling (which Unifi does not use for standard REPREVE).

REPREVE is sold across multiple variants:

VariantFeedstockDistinguishing feature
REPREVEPost-consumer PET bottles (curbside) + some post-industrialStandard product; FiberPrint + U-TRUST + GRS + OEKO-TEX 100 + SCS
REPREVE Our OceanBottles collected within 50 km of coastlineOceanCycle certification; addresses coastal-bound plastic specifically
REPREVE Takeback100% recycled materials, ≥50% post-industrial and post-consumer textile waste (per Unifi spec)Augmented thermomechanical process; addresses textile-to-textile gap
REPREVE ReCirculatePET feedstock variantReformulated supply chain
REPREVE NylonPre-consumer carpet-fiber waste (nylon 6, not PET)Polymer is polyamide, not PET; chip is “REPREVE Nylon chip 6”
REPREVE with CiCLO®PET bottles with CiCLO biodegradation additiveLaunched April 2025; intended biodegradation in soil/seawater
ThermaLooprPET insulation formInsulation rather than woven/knit fabric

Unifi’s FY2025 Sustainability Snapshot (released February 24, 2026) reports REPREVE uses multiple waste sources — single-use plastic bottles, ocean-bound plastic, textile waste, and recycled yarn — but does not publicly disclose a quantitative post-consumer-to-post-industrial split for standard REPREVE polyester.

Mechanical vs Chemical Recycling — Where REPREVE Sits

Polyester recycling falls into two technical categories. The distinction is missing from every top-ranking SERP page on REPREVE despite being central to the recycled fiber’s performance properties.

Thermomechanical recycling physically re-processes existing PET. Bottles are washed, shredded, melted, and re-extruded. The polymer chains remain intact in principle, but each thermal cycle causes some chain scission — molecular weight drops, intrinsic viscosity decreases, crystallinity falls. Welle (2011) measured the intrinsic viscosity of post-recycled PET at 0.65-0.72 dL/g versus 0.78-0.85 dL/g for virgin. This is the path REPREVE takes.

Chemical (or “feedstock”) recycling depolymerizes PET back to its monomers — bis(2-hydroxyethyl) terephthalate, ethylene glycol, and dimethyl terephthalate or terephthalic acid — through glycolysis, methanolysis, hydrolysis, or enzymatic processes. Re-polymerized PET from chemical recycling is virgin-equivalent in molecular weight and tenacity. Eastman Renew, Loop Industries, and Teijin Eco Circle take this path. REPREVE does not.

A measured comparison of mechanical and chemical rPET grades shows the trade-off:

AttributeThermomechanical (REPREVE)Chemical depolymerization
Polymer integrityReduced IV (0.65-0.72 dL/g per Welle 2011)Virgin-equivalent IV
Tenacity vs virgin5-15% lower (Akyildiz 2024)Comparable to virgin
Energy intensityLower (no monomer regeneration step)Higher
Cost per kgLowerHigher (typically 2-3× per industry estimates)
Output colorSlight yellow/grey tint without bleachingClear / white
Feedstock toleranceRequires high-purity PET (food-grade bottles)Tolerates mixed/contaminated PET
Commercial scaleMature, ~9.3M tonnes/year globallyLimited; expanding through 2026

REPREVE Takeback uses an “augmented thermomechanical” process for textile-waste feedstock — still mechanical rather than chemical. The implication: REPREVE products inherit mechanical recycling’s polymer-level limitations and its energy-cost advantages.

Microfiber Shedding: What the Studies Show

Microplastic shedding is the central blind spot in current top-10 coverage of REPREVE. The evidence does not support the framing that recycled polyester sheds less than virgin polyester. The peer-reviewed literature is contested, but the weight of recent studies suggests mechanically recycled PET sheds equal-to-more microfibers than virgin PET — likely because lower molecular weight and crystallinity reduce fiber integrity during washing.

Study (author, year)Sample / methodFinding (rPET vs virgin PET)Metric
Çukurova / Changing Markets (2025), Spinning Greenwashn=51 garments incl. 23 polyester from Adidas, H&M, Nike, Shein, ZararPET sheds ~54.8% more; particles ~20% smaller~12,000 vs 8,028 fibers/g
Akyildiz et al. (2024), Environmental Pollution5 fabrics, ISO 105-C06 wash protocolrPET releases more microfibers at every wash stageImage-J count
Özkan & Gündoğdu (2020)Knitted rPET vs virgin PET, controlled washrPET releases approximately 2.3× more fibersCounts per wash
Sheridan / The Microfibre Consortium (2023)n=251 fabrics, industry-fundedNo statistically meaningful differenceMass-based
De Falco et al. (2019), Sci. Rep. 9:6633Polyester garments, household washing124-308 mg microfibers per kg loadGravimetric
Pinlova, Hufenus, Nowack (2022), J. Clean. Prod. 363:132247Yarn-production stagePolyester yarn sheds during production, not only launderingMultiple methods

Three drivers govern shedding rates independently of “recycled” status:

  1. Yarn construction. Loosely twisted yarns shed more than tightly twisted yarns. Spun staple sheds more than continuous filament. Hairy yarns shed more than smooth yarns.
  2. Fabric construction. Knitted fabrics shed more than woven fabrics at comparable mass. Lower fabric density (open weaves, sparse knits) sheds more.
  3. Polymer integrity. Lower molecular weight and lower crystallinity reduce fiber strength, which increases shedding. This is where mechanical rPET is structurally disadvantaged versus virgin PET.

The honest framing for REPREVE specifically: REPREVE is chemically PET, sheds microfibers, and is governed by the same fabric-construction variables as any polyester. The recycled feedstock does not reduce shedding and may slightly increase it depending on fabric construction. Standard ISO 4484-1:2023 testing for textile microplastic release is now available; published REPREVE-specific results to that standard are not yet visible in the academic literature as of April 2026.

For the broader microplastic context across all polyester garments — including the same kind of bacterial adsorption that affects polyester odor retention — the recycled-versus-virgin distinction is secondary to fabric construction and washing temperature.

Energy, Water, and CO₂: What the 2023 LCA Actually Says

Unifi published an updated Life Cycle Assessment for REPREVE on July 26, 2023 (Business Wire press release, GREENSBORO, NC), described as “independent peer-reviewed.” The headline numbers — and the qualifications that should accompany them — are below.

Impact categoryREPREVE filament (DTY) reduction vs virgin filamentREPREVE staple fiber reduction vs virgin staple
Greenhouse gas emissions-42%-60%
Fossil fuel depletion-66%-76%
Water scarcity-76%not disclosed
Freshwater consumption-67%not disclosed

Source: Unifi 2023 LCA via Business Wire press release (July 26, 2023). Unifi describes the LCA as “independently produced based on ISO 14040 and 14044, and third-party reviewed according to ISO 14071” — that is, ISO-standard third-party review rather than journal peer-review in the traditional sense. The full underlying LCA dataset is not currently available in the indexed academic literature as of May 2026.

Several older Unifi marketing figures continue to circulate downstream — “62% less energy,” “99% less water,” “35% less waste,” “20% less CO₂” — that predate the 2023 LCA and use different methodology. Mixing the two number sets misrepresents the data. The 2023 LCA values are the current technical reference.

The “saves drinking water for 3.5 billion people” and “energy for 280,000 homes” equivalency claims that appear on apparel-decorator and DTC brand pages are per-pound extrapolations from cumulative bottle counts. They are not annualized impact figures and are not independently audited at the cumulative level.

Certifications Explained — What GRS, OEKO-TEX, SCS, and U-TRUST Actually Verify

Each certification carried by REPREVE verifies a different attribute. None of them is a single comprehensive sustainability seal; reading the label requires distinguishing what each one tests.

CertificationAdministered byTests / verifiesDoes NOT test
Global Recycled Standard (GRS)Textile Exchange (independent multi-stakeholder)Recycled content (≥20% “made with”; ≥50% full label), supply chain custody, social/environmental criteria, restricted substance listMicrofiber shedding; final-product strength
OEKO-TEX Standard 100OEKO-TEX Association (independent)Restricted substances (>100 chemicals); product class I-IV by skin contactRecycled content; sustainability claims; biodegradability
SCS Recycled ContentSCS Global Services (independent third-party)Recycled-input claim per ISO 14021Polymer-level strength; chemical contaminants
U-TRUSTUnifi (proprietary, third-party-lab tested)Presence of FiberPrint tracer; ≥30% REPREVE yarn threshold; annual renewalWider sustainability or chemical criteria
OceanCycle (REPREVE Our Ocean only)OceanCycle (independent)Coastal-bound feedstock origin (within 50 km of coast)Chemical residues; polymer integrity

GRS is the most rigorous of the recycled-content seals because it audits the chain of custody, requires environmental and social criteria, and includes a restricted substance list. OEKO-TEX Standard 100 confirms the fiber meets a chemical safety threshold but does not confirm any sustainability claim. SCS independently verifies the recycled-content claim per ISO 14021 (the standard that governs self-declared environmental claims and that the FTC Green Guides cite for U.S. enforcement).

U-TRUST occupies a different position: it is administered by Unifi (the manufacturer) using independent laboratories. It is “third-party tested” but is not “third-party administered” in the same sense as GRS. The 30% minimum REPREVE yarn threshold for U-TRUST is published in supplier-facing documentation and surfaced occasionally in industry reporting (e.g., Digital Output Magazine).

The certification picture for REPREVE is layered: the underlying recycled content is GRS- and SCS-verified, the chemical safety is OEKO-TEX-verified, and the brand-specific tracer is U-TRUST-verified. Each layer addresses a different audit question.

REPREVE vs Other Recycled Polyester Brands

Recycled polyester is a category, not a single product. The brands below differ in recycling method, feedstock, and certification body.

BrandOwnerRecycling methodFeedstockVerification
REPREVEUnifi (USA)ThermomechanicalPost-consumer PET bottles + post-industrial; textile waste (Takeback)U-TRUST + FiberPrint, GRS, SCS, OEKO-TEX 100
NewlifeSinterama (Italy)MechanicalPost-consumer PET bottlesGRS, OEKO-TEX
Eco CircleTeijin (Japan)Chemical (depolymerization)Polyester garmentsGRS + internal
Eastman RenewEastman (USA)Chemical (methanolysis / glycolysis)Mixed plastic wasteGRS, ISCC+
Loop IndustriesLoop (Canada)Chemical (depolymerization to MEG/DMT)Mixed PET wastePatented; LCA published
Far Eastern New Century / Nan Ya rPETFENC, Nan Ya (Taiwan)MechanicalPost-consumer PET bottlesGRS

Chemically recycled brands (Eco Circle, Eastman Renew, Loop Industries) regenerate polymer integrity by returning PET to its monomer building blocks. Mechanically recycled brands (REPREVE, Newlife, FENC, Nan Ya) preserve the polymer chains but accept some molecular-weight reduction in exchange for lower energy intensity and more mature commercial scale. As of 2026, mechanical rPET dominates volume; chemical rPET is scaling but remains a small share.

Common Myths and Marketing Claims

Several claims about REPREVE circulate in apparel-brand and DTC content that do not survive a closer read.

  • “REPREVE is biodegradable.” False for standard REPREVE. PET persists in landfill 200+ years. Only REPREVE with CiCLO (April 2025 launch) contains an additive intended to support biodegradation. Standard REPREVE has the same persistence profile as virgin PET.
  • “REPREVE is plastic-free / natural.” False. PET is a synthetic petrochemically-derived polymer regardless of feedstock.
  • “REPREVE solves ocean plastic.” Partially true only for REPREVE Our Ocean (50 km coastal radius). Standard REPREVE uses curbside-collected post-consumer bottles, not ocean-recovered plastic.
  • “REPREVE is recyclable at end of life.” Technically yes; in practice, less than 1% of textiles globally are recycled fiber-to-fiber per the Ellen MacArthur Foundation (2017). PET-bottle-to-textile recycling removes the bottle from a more efficient bottle-to-bottle loop where bottle-grade PET can be recycled 5-9 times.
  • “Each REPREVE garment saves X bottles from landfill.” True for the diverted bottle, but the resulting garment then enters a non-recycled stream. Net waste impact is ambiguous beyond a single-use horizon.
  • “REPREVE has a zero carbon footprint.” False. The 2023 LCA reports CO₂-equivalent emissions for REPREVE — just lower than virgin PET. “Zero” is unsupported.
  • “REPREVE is hypoallergenic.” Unsupported as a textile claim. OEKO-TEX Standard 100 confirms restricted-substance limits but does not certify “hypoallergenic” — that is not a regulated textile claim under FTC Green Guides or 16 CFR 303 (Textile Fiber Products Identification Act).
  • “Recycled is the same as renewable.” False. Recycled feedstock postpones disposal; it does not regenerate. PET is a fossil-fuel-derived polymer regardless of recycling history.

The pattern across these claims: each one is true in a narrow technical sense and false when extended to consumer-facing copy without qualification. Distinguishing the underlying claim from the marketing extension is the central skill in reading REPREVE-content product pages.

For broader context on polyester safety, irritation, and the dye/finish chemistry that drives most reported reactions to PET garments, the polyester itching analysis covers the disperse-dye and formaldehyde-finish data that applies equally to REPREVE-content products. For the wider virgin-versus-recycled comparison across BPA, antimony, durability, and price premiums, the rPET versus virgin polyester comparison covers the data ranges. And for how REPREVE-grade fiber compares to natural alternatives like cotton, the polyester versus cotton fiber-property comparison lays out the moisture-regain and tenacity differences side by side.

Real-World Use: Where REPREVE Performs and Where It Doesn’t

REPREVE’s strongest use cases are applications where PET is already the right material — where moisture absorption is a disadvantage, where dimensional stability matters, where UV resistance matters, and where recycled content provides a verifiable upstream impact reduction without compromising function.

Performs well in:

  • Performance activewear (engineered tri-lobal or hollow-filament wicking constructions); the FiberPrint-traced supply chain provides documented recycled content. Wicking and engineered constructions do not change the raw material — REPREVE is still PET; microfibers shed in every wash (mechanical rPET sheds approximately 54.8% more than virgin PET per Çukurova/Changing Markets 2025), and post-disposal biodegradation takes 200+ years. Engineered rPET in a skin-contact athletic context is a conscious athletic choice, not a default recommendation
  • Outerwear shells where UV resistance and dimensional stability matter
  • Technical fabrics for outdoor products
  • Insulation (ThermaLoop) where fiber loft and consistency matter
  • Automotive interior textiles (Ford, Toyota REPREVE applications)
  • Mattress covers and bedding shells (Brentwood Home applications)

Performs less well in:

  • Applications where moisture absorption matters (regain ~0.4% means PET cannot manage the skin microclimate the way cotton can — see the cotton-versus-polyester breathability data)
  • High-friction abrasion applications versus virgin PET, where the 5-15% tenacity reduction in mechanical rPET may matter
  • Applications where microfiber shedding is the primary environmental concern; mechanical rPET does not reduce shedding

The polymer-level limitations of polyester apply in full to REPREVE: hydrophobic surface that adsorbs sebum (which underlies polyester odor retention), low moisture regain, and persistence in non-recycled disposal streams. These are PET properties, not REPREVE-brand properties.

Methodology and Sourcing

The polymer-level data in this article is sourced from primary textile science references (Welle 2011; Awaja & Pavel 2005; Akyildiz et al. 2024) and standard test methods (ASTM D2654 for moisture regain, ISO 5079 for fiber tenacity, ISO 105-C06 for wash protocol, ISO 4484-1:2023 for textile microplastic release). LCA data is sourced from Unifi’s July 26, 2023 Business Wire press release describing an updated peer-reviewed LCA. Microfiber shedding data is sourced from Çukurova University / Changing Markets Foundation (2025), Akyildiz et al. (2024) in Environmental Pollution, Özkan & Gündoğdu (2020), and The Microfibre Consortium / Sheridan (2023). Marketing claims that could not be cross-verified against primary or peer-reviewed sources are flagged as “Unifi marketing materials, not independently audited” rather than restated as facts.

For the broader sourcing approach across natuclothes.com fabric science articles, see the data sourcing methodology.

Sources

Standards:

  • ISO 2076:2021 — Textiles. Man-made fibres. Generic names. iso.org/standard/79685
  • ISO 4484-1:2023 — Textiles and textile products. Microplastics from textile sources. Part 1: Determination of material loss from fabrics during washing. iso.org/standard/82238
  • ISO 105-C06 — Colour fastness to domestic and commercial laundering (used as standard wash protocol). iso.org/standard/51276
  • ISO 14021 — Self-declared environmental claims (Type II environmental labelling). iso.org/standard/66652
  • ISO 5079 — Textile fibres. Determination of breaking force and elongation at break of individual fibres. iso.org/standard/79885
  • ISO 12947 — Textiles. Determination of abrasion resistance by the Martindale method. iso.org/standard/21261
  • ASTM D2654-22 — Standard Test Methods for Moisture in Textiles. astm.org/d2654-22
  • ASTM D3884 — Standard Guide for Abrasion Resistance of Textile Fabrics (Rotary Platform, Double-Head Method). astm.org
  • ASTM D5034 — Standard Test Method for Breaking Strength and Elongation of Textile Fabrics (Grab Test). astm.org
  • AATCC 195 — Liquid Moisture Management Properties of Textile Fabrics. aatcc.org
  • 16 CFR 303 — FTC Textile Fiber Products Identification Act (TFPIA). ftc.gov

Peer-reviewed studies:

  • Akyildiz, S.H., Fiore, S., Bruno, M., Sezgin, H., Yalcin-Enis, I., Yalcin, B., Bellopede, R. (2024). “Release of microplastic fibers from synthetic textiles during household washing.” Environmental Pollution 357, 124455. doi.org/10.1016/j.envpol.2024.124455
  • Awaja, F. & Pavel, D. (2005). “Recycling of PET.” European Polymer Journal 41, 1453-1477. doi.org/10.1016/j.eurpolymj.2005.02.005
  • De Falco, F., Di Pace, E., Cocca, M., Avella, M. (2019). “The contribution of washing processes of synthetic clothes to microplastic pollution.” Scientific Reports 9, 6633. doi.org/10.1038/s41598-019-43023-x
  • De Falco, F., Cocca, M., Avella, M., Thompson, R. (2020). “Microfiber Release to Water, Via Laundering, and to Air, via Everyday Use.” Environmental Science & Technology 54, 3288-3296. doi.org/10.1021/acs.est.9b06892
  • Özkan, İ. & Gündoğdu, S. (2020). “Investigation on the microfibre release under controlled washings from the knitted fabrics produced by recycled and virgin polyester yarns.” The Journal of The Textile Institute 112(2). doi.org/10.1080/00405000.2020.1741760
  • Pinlova, B., Hufenus, R., Nowack, B. (2022). “Systematic study of the presence of microplastic fibers during polyester yarn production.” Journal of Cleaner Production 363, 132247. doi.org/10.1016/j.jclepro.2022.132247
  • Sheridan, K. / The Microfibre Consortium (2023). Industry-funded fiber-fragmentation study, n=251 fabrics. (Textual citation — no stable DOI.)
  • Volgare, M., De Falco, F., Avolio, R., et al. (2021). “Washing load influences the microplastic release from polyester fabrics by affecting wettability and mechanical stress.” Scientific Reports 11, 19479. doi.org/10.1038/s41598-021-98836-6
  • Welle, F. (2011). “Twenty years of PET bottle to bottle recycling — An overview.” Resources, Conservation and Recycling 55(11), 865-875. doi.org/10.1016/j.resconrec.2011.04.009

Reports and industry sources:

  • Changing Markets Foundation / Microplastic Research Group, Çukurova University (December 2025). Spinning Greenwash: How the fashion industry’s shift to recycled polyester is worsening microplastic pollution. (Textual citation.)
  • Ellen MacArthur Foundation (2017). A New Textiles Economy: Redesigning Fashion’s Future. ellenmacarthurfoundation.org
  • Unifi, Inc. / Business Wire (July 26, 2023). “UNIFI Announces Updated Life Cycle Data Confirming Certain Environmental Benefits of REPREVE Polyester.” (Textual citation — press release.)

Brands and certifications: