# Bio-bitumen & bio-asphalt (lignin binders)

Bio-bitumen and bio-asphalt replace or extend petroleum bitumen with plant-oil and lignocellulosic-biomass binders and rejuvenators. SoyLei's SIP-1111 Rejuv (sub-epoxidized soybean oil, SESO) completed AASHTO's Asphalt Mixture Recycling Agent DataMine pathway (report AMRA-2025-02-003, May 2026), enabling 45%+ reclaimed-asphalt-pavement (RAP) mixes; Sripath Technologies' ReLIXER/PGXpand/ButaPhalt suite is deployed on high-RAP projects in the US, Australia, Ireland and elsewhere, including a 100%-RAP New York City project. Colas's Vegecol and Vegeroad Bitumen (majority-plant-oil binders) cut asphalt carbon footprint up to 70% and CO2 emissions up to 30% versus conventional bitumen, rolled out across France, Denmark and other European markets. In India, CSIR-CRRI and CSIR-IIP transferred an indigenous bio-bitumen technology (pyrolysis of rice-straw and other farm residue into bio-oil, blended 20-30% with conventional bitumen) for national-highway adoption, targeting India's roughly 50% bitumen import dependence.

Source: https://en.bioecon.ru/technology/bio-bitumen-bio-asphalt-lignin-binders/
Updated: 2026-08-18



## Overview and value chain

Markers: [EC: AASHTO Asphalt Mixture Recycling Agent (AMRA) evaluation pathway / EU REACH bio-based binder chemical registration / EPA VOC & bitumen-fume exposure oversight | OECD: Bio-based materials | Regulator: EPA (USA), REACH (EU)]

Bio-bitumen and bio-asphalt replace or extend petroleum-derived bitumen binder — the fossil-refinery residue that binds aggregate into asphalt pavement — with plant-oil-derived rejuvenators, vegetable-oil binders, and pyrolysis bio-oil from lignocellulosic agricultural residue. Four distinct product families are commercializing in 2026: **bio-based recycling-agent rejuvenators** for reclaimed asphalt pavement (RAP), led by SoyLei's sub-epoxidized soybean oil (SESO) chemistry, which completed AASHTO's formal Asphalt Mixture Recycling Agent (AMRA) DataMine evaluation pathway (report AMRA-2025-02-003) in May 2026, third-party tested head-to-head against competitors by the National Road Research Alliance (NRRA) and the Minnesota DOT; **globally deployed bio-based additive suites** combining rejuvenators, warm-mix agents and polymer-modifier crosslinkers, led by Sripath Technologies' ReLIXER®, PGXpand®, and ButaPhalt®, field-proven on projects from 40% RAP (Illinois Tollway, Gold Coast Australia) to 100% RAP with no additional virgin binder (New York City); **majority-plant-oil bio-binders** that substitute directly for virgin bitumen in new asphalt mixes, led by Colas's Vegecol (low-carbon light-colored urban asphalt, up to 70% carbon-footprint reduction) and Vegeroad Bitumen (up to 30% CO2 reduction, rolled out across France, Denmark and other Colas Group markets); and **lignocellulosic pyrolysis bio-oil binders**, led by India's CSIR-Central Road Research Institute (CSIR-CRRI) and CSIR-Indian Institute of Petroleum (CSIR-IIP), which transferred an indigenous technology converting rice straw and other crop residue into bio-oil via pyrolysis, validated to replace 20-30% of conventional bitumen without compromising performance. Reclaimed asphalt pavement (RAP) reuse is the connective thread across all four families: the US alone generates over 750 million tons of RAP annually (National Asphalt Pavement Association), and bio-based rejuvenators are the mechanism that lets high-RAP mixes (40-100% RAP) meet the same cracking-resistance and rutting specifications as low-RAP mixes.

The key directions of bio-bitumen and bio-asphalt are:
1. **Bio-based AMRA rejuvenators (sub-epoxidized soybean oil, SESO):** SoyLei's SIP-1111™ Rejuv family (SIP-1111, SIP-1111P polymer-modified, SIP-1111-CIR for cold-in-place recycling and foamed asphalt) — completed AASHTO's Asphalt Mixture Recycling Agent DataMine pathway (AMRA-2025-02-003, May 2026); at a 45% RAP mixture and 3.2% dosage, moved binder Delta Tc from -2.8°C to +0.5°C (one-PAV) and -4.0°C to -0.1°C (two-PAV), improved IDEAL-CT from 14.6 to 16.7 (short-term) and 4.2 to 4.8 (long-term aging), while keeping Hamburg rut depth low (3.5mm vs 3.1mm control at 20,000 passes); commercially available, ships within 1 week of purchase order.
2. **Global bio-based RAP-rejuvenator and polymer-modifier suites:** Sripath Technologies' ReLIXER® (bio-based rejuvenator, field-proven at 40% RAP with regular binder in Illinois and Gold Coast Australia, 60% RAP in Dublin Ireland, 100% RAP with no additional binder in New York City), PGXpand® (bitumen and roofing-membrane modifier raising softening point while preserving low-temperature flexibility), and ButaPhalt® (crosslinking additive for polymer-modified bitumen blends).
3. **Vegetable-oil / lignin bio-binders substituting virgin bitumen:** Colas's Vegecol (majority-plant-oil-bound light-colored asphalt for urban developments and soft-mobility paths, up to 70% carbon-footprint reduction, reduces surface-heat absorption via light color) and Vegeroad Bitumen (vegetable-oil-content bitumen, up to 30% CO2 reduction, life-cycle-mapped via the French SEVE environmental-impact system, rolled out in France, Denmark, and other Colas Group countries at cost near parity with conventional bitumen).
4. **Lignocellulosic pyrolysis bio-oil binders:** CSIR-CRRI and CSIR-IIP's indigenous "Bio-Bitumen from Lignocellulosic Biomass" technology — thermochemical pyrolysis of post-harvest rice straw and other crop residue into bio-oil, blended with conventional bitumen at a validated 20-30% replacement ratio without compromising road performance, transferred for large-scale industrial adoption (New Delhi technology-transfer events, January and March 2026) targeting India's roughly 50% bitumen import dependence and addressing agricultural stubble-burning.

### Sectoral value chain

```
[soybean oil / vegetable oil / crop-residue feedstock] ──> [oil extraction / pyrolysis of biomass]
                                                                          │
                                                          (SESO / bio-oil / plant-oil binder)
                                                                          │
                                                                          ▼
[finished rejuvenator / bio-binder tote / tanker] <─── [inline blending with virgin/reclaimed bitumen] <─── [AASHTO/lab qualification testing] <─── [chemical/thermal conversion (epoxidation / pyrolysis / esterification)]
```

### Value chain levels

| Level | Description | Key inputs/outputs |
|:---|:---|:---|
| **Feedstock cultivation & extraction** | soybean oil (SoyLei SESO feedstock), vegetable/plant oils (Colas Vegecol/Vegeroad binder feedstock), agricultural crop residue — post-harvest rice straw and farm stubble (CSIR-CRRI/CSIR-IIP pyrolysis feedstock) | **In:** agricultural feedstock, crop residue.<br>**Out:** crude vegetable oil or baled/pelletized biomass. |
| **Chemical/thermal conversion** | partial epoxidation of soybean oil (soybean oil + oxidant → SESO, SoyLei); thermochemical pyrolysis of lignocellulosic biomass (crop residue → bio-oil, CSIR-CRRI/CSIR-IIP); formulation of vegetable-oil bitumen binders (Colas Vegecol/Vegeroad); crosslinking chemistry for polymer-modified binders (Sripath ButaPhalt) | **In:** crude vegetable oil / biomass feedstock.<br>**Out:** SESO rejuvenator, bio-oil, or bio-binder intermediate. |
| **Qualification & testing** | AASHTO DataMine AMRA evaluation (chemical fingerprinting, MSCR, Delta Tc, Hamburg Wheel Tracking, IDEAL-CT, Overlay testing — SoyLei); French SEVE environmental life-cycle mapping (Colas); laboratory validation of 20-30% bitumen replacement ratio (CSIR-CRRI/CSIR-IIP) | **In:** rejuvenator/bio-oil/binder intermediate.<br>**Out:** AASHTO-qualified or lab-validated bio-binder product. |
| **Blending & formulation** | inline blending of rejuvenator with virgin or reclaimed binder (SoyLei SIP-1111 inline-blended with 58-28S virgin binder); global RAP-rejuvenator dosing (Sripath ReLIXER at 40-100% RAP); vegetable-oil binder mixed into asphalt at plant (Colas); bio-oil blended 20-30% with conventional bitumen at refinery/plant (CSIR-CRRI) | **In:** qualified rejuvenator/binder + virgin bitumen, aggregate, or RAP.<br>**Out:** finished asphalt mix or bitumen binder blend. |
| **End-use paving & roofing** | high-RAP road paving (state DOT and municipal highway projects), low-carbon urban asphalt and soft-mobility paths (Vegecol), cold-in-place recycling and foamed asphalt (SoyLei SIP-1111-CIR), roofing membranes (Sripath PGXpand) | **In:** finished bio-binder asphalt mix.<br>**Out:** paved road surface or roofing membrane. |
| **Recycling & end-of-life** | milling and reclamation of aged pavement into RAP stockpiles, fractionated and homogenized for reuse; RAP content up to 100% achievable with bio-based rejuvenators (Sripath ReLIXER, New York City) | **In:** end-of-life asphalt pavement.<br>**Out:** reclaimed asphalt pavement (RAP) feedstock for the next paving cycle. |

Cross-cutting technologies of the sector:
- **Sub-epoxidized soybean oil (SESO) AMRA rejuvenator (SESO Sub-Epoxidized Soybean Oil Rejuvenator):** SoyLei's SIP-1111™ platform — the first commercial rejuvenator to complete AASHTO's Asphalt Mixture Recycling Agent DataMine evaluation pathway (AMRA-2025-02-003), giving state DOTs and agencies a recognized, standardized data package rather than a vendor-only claim; NRRA/MnDOT third-party head-to-head testing over 2 years confirmed field performance.
- **Bio-based RAP-rejuvenator and polymer-modifier suite (Bio-Based RAP Rejuvenator Suite):** Sripath Technologies' ReLIXER/PGXpand/ButaPhalt — deployed across four+ countries (US, Australia, Ireland) at RAP contents from 40% to 100%, positioned as a global rather than single-market platform, with roofing-membrane as well as roadway applications.
- **Vegetable-oil / lignin bio-binder (Vegetable Oil Lignin Bio-Binder):** Colas's Vegecol and Vegeroad Bitumen — majority-plant-oil binders substituting directly for virgin bitumen, life-cycle-mapped via the SEVE system, deployed at near-cost-parity across multiple European Colas Group markets.
- **Lignocellulosic pyrolysis bio-oil binder (Lignocellulosic Pyrolysis Bio-Oil Binder):** CSIR-CRRI/CSIR-IIP's thermochemical conversion of post-harvest crop residue into bio-oil for blending with conventional bitumen — the only pathway in this set that converts agricultural waste (addressing stubble burning) directly into a national-highway-grade binder component.

---

## US

The US is the centre of AASHTO-pathway-validated bio-based rejuvenators and globally deployed bio-based bitumen additive suites, driven by state DOT high-RAP recycling programs and the AASHTO/NCAT technical evaluation framework rather than a single federal mandate.

### SoyLei's AASHTO-validated SESO rejuvenator, Sripath's global ReLIXER/PGXpand/ButaPhalt suite
- **SoyLei (Iowa):** transforms soybean oil into the SIP-1111™ Rejuv family of high-performance, cost-effective rejuvenators, additives and sprays; SIP-1111™ Rejuv completed AASHTO's Asphalt Mixture Recycling Agent evaluation pathway and received an AASHTO DataMine AMRA report (AMRA-2025-02-003, published May 15, 2026) identifying the chemistry as sub-epoxidized soybean oil (SESO); a 45% RAP / 3.2% dosage evaluation showed clear low-temperature cracking-resistance improvement (Delta Tc, IDEAL-CT) while keeping Hamburg rutting low; third-party tested head-to-head against competitors by the National Road Research Alliance (NRRA) and Minnesota DOT over two years; commercially available in totes, tankers and rail, shipping within 1 week of purchase order; SIP-1111-CIR extends the chemistry to cold-in-place recycling and foamed asphalt.
- **Sripath Technologies (Mahwah, New Jersey, founded 2006):** develops, manufactures and markets ReLIXER® (bio-based asphalt rejuvenator), PGXpand® (binder/roofing-membrane performance modifier) and ButaPhalt® (polymer-modified-bitumen crosslinking additive); ReLIXER field deployments span the Illinois Tollway (40% RAP with regular binder), City of Gold Coast Australia (40% RAP with polymer-modified binder), Dublin Ireland (60% RAP with regular binder), and New York City (100% RAP with no additional binder); President Dr. Krishna Srinivasan (25+ years in the bitumen industry) presented high-RAP mix-design strategy via a University of Oklahoma / Southern Plains Transportation Center webinar (May 2025).
- **AASHTO Asphalt Mixture Recycling Agent (AMRA) evaluation pathway:** developed with NCAT as a structured process comparing a high-RAP mix with and without a candidate recycling agent — chemical fingerprinting, dosage selection, binder grading, MSCR, Delta Tc, volumetric verification, Hamburg Wheel Tracking, IDEAL-CT, and Overlay testing; the resulting AASHTO DataMine report gives contractors, terminals, agencies and consultants a common, recognized data package (final QPL/allow-list decisions remain with each state agency) — the regulatory-adjacent gate every new US bio-based rejuvenator increasingly needs to pass to reach state DOT specifications.

---

## CN

China's domestic industry-research publishers (产业调研网, chinabgao.com) track a fast-growing bio-asphalt and bio-based bitumen market in their 2026 sector reports, but live sourcing in this cycle did not surface a company- or institute-specific 2026 bio-bitumen commercial launch or technology-transfer event on the scale of the SoyLei AASHTO pathway, Colas Vegecol/Vegeroad rollout, or CSIR-CRRI/CSIR-IIP technology transfer — so no Chinese producer is tabled this cycle, a qualitative disclosure rather than a fabricated row.

### Market research signals without a confirmed 2026 producer event
- **产业调研网 / chinabgao.com sector reports:** multiple 2025-2026-dated Chinese market-research reports track "生物沥青" (bio-asphalt) and "生物基沥青" (bio-based bitumen) as an emerging category alongside conventional road-modified-bitumen research, but these are industry forecasts and report listings rather than company- or institute-specific sourced events; per this project's re-verify discipline, a market-report mention is not sufficient to table a specific producer.
- **Directional context:** reported Chinese interest in bio-asphalt tracks the same drivers visible in the US and India blocks — petroleum-import substitution and highway-construction decarbonisation — and China already participates in the global bio-based-rejuvenator supply chain indirectly (Sripath Technologies' ReLIXER is deployed regionally in the Asia-Pacific market, e.g. City of Gold Coast, Australia); a China-specific producer confirmation is a candidate for a future enrichment pass rather than this cycle's tabled set.

---

## EU

The EU's bio-bitumen leadership sits with Colas (France), whose Vegecol and Vegeroad Bitumen majority-plant-oil binders are commercially rolled out across multiple European Colas Group markets, with EU REACH governing the chemical registration of new bio-based binder formulations.

### Colas Vegecol low-carbon urban asphalt, Vegeroad Bitumen CO2 reduction
- **Colas (part of the Colas Group, France):** developed Vegecol, a light-colored asphalt mix with a majority-plant-based binder designed for urban developments, soft-mobility paths and public spaces — its bio-sourced binder and innovative formulation reduce carbon footprint by up to 70% versus traditional solutions while maintaining expected performance for urban and light-traffic infrastructure; its light color limits heat absorption, reducing surface temperatures in heavily sun-exposed areas, and it can be paired with draining structures for natural rainwater infiltration; deployed on projects including the Place d'Armes renovation for the 13th Engineer Regiment (13ème Régiment du Génie).
- **Vegeroad Bitumen (Colas, deployed in France, Denmark and other Colas Group markets):** a bitumen containing vegetable oils that reduces CO2 emissions by approximately 30% in asphalt production; tested for two years in Morsø Kommune, Denmark with results confirming equivalent quality and durability to conventional asphalt, then commercially rolled out in Helsingør (2026) and Brøndby (2025) municipalities; life-cycle-mapped against greenhouse-gas emissions, energy use, resource consumption, waste production, and air/water pollution using the French SEVE environmental-impact-comparison system; priced not significantly higher than conventional-bitumen asphalt.
- **EU REACH bio-based binder registration:** new bio-based bitumen binder and rejuvenator formulations entering EU markets register their chemical constituents under REACH — the same registration framework governing conventional bitumen and asphalt-additive chemistry, positioning REACH as the primary EU regulatory touchpoint for this Industry rather than a bitumen-specific regulator.

---

## Leading companies and research institutes

| Company / Institute | Country | Key products / platforms | Tech features | Status 2026 |
|:---|:---|:---|:---|:---|
| **SoyLei** | 🇺🇸 USA | *SIP-1111™ Rejuv family (SESO rejuvenator); SIP-1111-CIR (cold-in-place)* | AASHTO DataMine AMRA-2025-02-003 (May 2026); sub-epoxidized soybean oil chemistry; NRRA/MnDOT 2-year field testing; ships within 1 week | commercial |
| **Sripath Technologies** | 🇺🇸 USA | *ReLIXER® (bio-based rejuvenator); PGXpand®; ButaPhalt®* | Mahwah NJ, founded 2006; deployed Illinois Tollway/Gold Coast Australia (40% RAP)/Dublin (60% RAP)/NYC (100% RAP); President Dr. Krishna Srinivasan | commercial |
| **Colas** | 🇫🇷 France | *Vegecol (majority-plant-oil urban asphalt); Vegeroad Bitumen (vegetable-oil binder)* | Vegecol up to 70% carbon-footprint reduction; Vegeroad ~30% CO2 reduction; SEVE life-cycle mapping; France/Denmark rollout | commercial |
| **CSIR-CRRI** | 🇮🇳 India | *Bio-Bitumen from Lignocellulosic Biomass (with CSIR-IIP)* | Pyrolysis of rice straw/farm residue; 20-30% conventional-bitumen replacement validated; New Delhi tech-transfer events Jan/Mar 2026; targets ~50% bitumen import dependence | pilot |

---

## Tech stack and innovations

The bio-bitumen stack rests on two orthogonal conversion routes — plant-oil chemistry (epoxidation, esterification, direct vegetable-oil blending) and lignocellulosic-biomass pyrolysis — feeding two distinct product classes: RAP rejuvenators that restore aged binder, and virgin-bitumen-substituting bio-binders.

1. **Sub-epoxidized soybean oil (SESO) AMRA rejuvenator:**
   - SoyLei's SIP-1111™ chemistry reacts with damaged sites in aged asphalt binder, reversing age-related stiffness and restoring flexibility; the AASHTO DataMine AMRA-2025-02-003 evaluation (45% RAP, 3.2% dosage) documented a shift from a stiffer, more crack-prone binder profile (-2.8°C one-PAV Delta Tc) toward a healthier relaxation profile (+0.5°C) after aging, while Hamburg rut depth stayed low (3.5mm vs 3.1mm control).
   - The AASHTO Asphalt Mixture Recycling Agent pathway itself is a technology-adjacent innovation: a standardized, agency-recognized data package (chemical fingerprinting through Overlay testing) that lets any qualifying bio-based rejuvenator reach state DOT specification conversations on common technical ground rather than vendor-only claims.
2. **Global bio-based RAP-rejuvenator and polymer-modifier suite:**
   - Sripath's ReLIXER rejuvenates aged binder to enable RAP content from 30% up to 100% while maintaining functional properties, validated across four countries and both regular and polymer-modified binder systems; PGXpand raises softening point while preserving low-temperature flexibility for both roadway and roofing-membrane applications; ButaPhalt optimizes viscoelastic and storage-stability properties of polymer-modified-bitumen blends.
   - The breadth of deployment geography (US, Australia, Ireland) and application (roadway + roofing) distinguishes this suite from single-market or single-application rejuvenators.
3. **Vegetable-oil / lignin bio-binder:**
   - Colas's Vegecol and Vegeroad Bitumen substitute a majority-plant-oil binder directly for virgin petroleum bitumen rather than acting as a RAP rejuvenator — Vegecol targets low-traffic urban/soft-mobility applications with up to 70% carbon-footprint reduction and light-color heat-island mitigation, while Vegeroad Bitumen targets broader asphalt production with ~30% CO2 reduction at near-cost-parity with conventional bitumen.
   - Both are validated through France's SEVE life-cycle-impact-comparison system, giving municipal clients a standardized environmental case alongside the technical performance data from multi-year field trials (Morsø Kommune, Denmark).
4. **Lignocellulosic pyrolysis bio-oil binder:**
   - CSIR-CRRI and CSIR-IIP's thermochemical process collects post-harvest rice straw and other crop residue, pelletizes it, pyrolyzes it into bio-oil, then blends the bio-oil with conventional bitumen — laboratory validation confirmed 20-30% of conventional bitumen can be safely replaced without compromising performance.
   - The technology directly converts an agricultural-waste disposal problem (stubble burning, a major seasonal air-pollution source in North India) into a national-highway-grade construction input, reducing bitumen import dependence in a country that currently imports roughly half its bitumen requirement.

---

## Value chains and production pipelines

### Industrial pipeline of bio-bitumen and bio-asphalt (AASHTO AMRA / EU REACH / EPA)

```
┌───────────────────────────┐      ┌───────────────────────────┐
│ 1. Feedstock cultivation  │ ───> │ 2. Oil extraction /       │
│    (soybean, vegetable    │      │    biomass pyrolysis      │
│    oil, crop residue)     │      │                           │
└───────────────────────────┘      └───────────────────────────┘
                                                  │
                                                  ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 4. Qualification &        │ <─── │ 3. Chemical/thermal       │
│    testing (AASHTO        │      │    conversion             │
│    AMRA, SEVE, lab)       │      │    (epoxidation/pyrolysis) │
└───────────────────────────┘      └───────────────────────────┘
              │
              ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 5. Blending &             │ ───> │ 6. End-use paving,        │
│    formulation            │      │    roofing & recycling    │
└───────────────────────────┘      └───────────────────────────┘
```

#### Stage 1: Feedstock cultivation & extraction
Soybean oil (SoyLei's SESO feedstock) is sourced from US soybean crush facilities near SoyLei's Iowa base; vegetable/plant oils (Colas Vegecol/Vegeroad feedstock) are sourced across Colas Group's European supply chains; post-harvest rice straw and other crop residue (CSIR-CRRI/CSIR-IIP feedstock) is collected from North Indian farms as part of a stubble-management program that reduces seasonal open-field burning.

#### Stage 2: Oil extraction / biomass pyrolysis
Crude soybean and vegetable oil are extracted by conventional pressing/refining; crop residue is baled, pelletized, and thermochemically pyrolyzed by CSIR-IIP's process into a bio-oil intermediate — the two routes diverge here into an oil-chemistry branch (SoyLei, Colas) and a biomass-thermal branch (CSIR-CRRI/CSIR-IIP).

#### Stage 3: Chemical/thermal conversion
Partial epoxidation converts soybean oil into SESO (SoyLei's SIP-1111 chemistry); Sripath's ButaPhalt uses crosslinking chemistry to modify polymer-bitumen blends; Colas formulates Vegecol/Vegeroad as majority-plant-oil binders; CSIR-IIP's pyrolysis bio-oil is the direct thermal-conversion product of Stage 2, requiring no separate chemical step before blending.

#### Stage 4: Qualification & testing
SoyLei's SIP-1111 passed the AASHTO DataMine Asphalt Mixture Recycling Agent evaluation (chemical fingerprinting, MSCR, Delta Tc, Hamburg Wheel Tracking, IDEAL-CT, Overlay testing) and two years of NRRA/MnDOT third-party field testing; Colas life-cycle-maps Vegecol/Vegeroad through the French SEVE system; CSIR-CRRI/CSIR-IIP laboratory-validated the 20-30% bitumen-replacement ratio for road performance equivalence.

#### Stage 5: Blending & formulation
SIP-1111 is inline-blended with virgin binder (e.g. 58-28S) or dosed into RAP mixes at 3.2%+ by weight of virgin asphalt binder; Sripath's ReLIXER is dosed to match RAP content from 30% to 100%; Colas blends Vegecol/Vegeroad plant-oil binder into asphalt mix at the plant; CSIR-CRRI/CSIR-IIP's bio-oil is blended with conventional bitumen at a 20-30% replacement ratio.

#### Stage 6: End-use paving, roofing & recycling
High-RAP road paving for state DOT and municipal highway projects (US), low-carbon urban asphalt and soft-mobility paths (Colas Vegecol, France), national-highway construction (India, Ministry of Road Transport and Highways adoption pathway), roofing-membrane applications (Sripath PGXpand); end-of-life pavement is milled, fractionated, homogenized and returned to the cycle as RAP feedstock — bio-based rejuvenators are what let that RAP content climb from the traditional 20-30% ceiling to 40-100% without sacrificing cracking resistance or rutting performance.