# Antifouling bio-coatings (marine)

Ship-hull coatings that prevent marine biofouling using biological repellents, self-polishing polymers and biomimetic surface texture instead of toxic heavy-metal biocides.

Source: https://en.bioecon.ru/technology/antifouling-bio-coatings-marine/
Updated: 2026-08-18



## Overview and value chain

Markers: [EC: Biocidal Products Regulation (BPR) & marine-coating VOC standards | OECD: bio-materials | Regulator: EPA (US), REACH (EU), NMPA (CN)]

Marine antifouling bio-coatings prevent algae, mussels and barnacles from colonizing ship hulls without relying on the toxic heavy-metal biocides (copper, tributyltin) that dominated the sector for decades and caused lasting damage to port and estuary ecosystems. The leading commercial route is the self-polishing copolymer (SPC), a resin that hydrolyzes slowly and evenly in seawater under hull friction to release a controlled, steady dose of repellent; AkzoNobel's International brand launched its Intersleek 2120 silicone foul-release coating in June 2026, while Jotun's Seaquantum Ultra S uses a one-component, chemically hydrolysing silyl-acrylate chemistry for stable self-polishing. Hempel completed the first newbuilding application of its next-generation Hempaguard NB silicone hull coating in 2026, applying it directly during vessel construction in partnership with Maersk and Yangzijiang Shipyard rather than only as an in-service retrofit. Biomimetic surface texturing (shark-skin- and lotus-leaf-inspired micropatterns) and enzymatic barriers that break down the protein "glue" barnacle larvae use to attach are the two fastest-growing biological alternatives to silicone/SPC chemistry, and reduced hull friction from any of these routes can cut a vessel's hydrodynamic drag enough to lower fuel burn and CO2 emissions.

The key directions of marine antifouling bio-coatings are:
1. **Self-polishing copolymers (SPC):** resin matrices that hydrolyze at a controlled rate in seawater, continuously renewing a smooth, repellent-releasing surface as the ship moves.
2. **Natural bioactive repellents:** compounds such as zosteric acid (from seagrass), tannins and chitosan used in place of copper or organotin biocides.
3. **Biomimetic surface texturing:** micro-patterned surfaces inspired by shark skin or lotus leaves that physically discourage larval settlement without releasing any biocide.
4. **Enzymatic antifouling:** protease and galactosidase enzymes embedded in the coating that break down the protein adhesive barnacle larvae use to attach to steel.

### Sectoral value chain

```
[Repellent/Enzyme Screening] ──> [Copolymer Synthesis & Formulation] ──> [Self-Polishing Matrix Production]
                                                                                  │
                                                                          (Airless spray in drydock)
                                                                                  │
                                                                                  ▼
[In-Service Fouling Monitoring] <─── [Hull Coating Application]
```

### Value chain levels

| Level | Description | Key inputs/outputs |
|:---|:---|:---|
| **1. Repellent/enzyme screening** | Identifying natural molecules (zosteric acid, tannins, chitosan) or enzymes with antifouling activity. | **In:** Marine plant/microbial extracts, enzyme libraries.<br>**Out:** Candidate bioactive repellents. |
| **2. Binder synthesis** | Synthesizing the self-polishing binder resin (e.g., a silyl-acrylate copolymer) that will carry the repellent. | **In:** Acrylate monomers, silicone precursors.<br>**Out:** Hydrolyzable copolymer binder. |
| **3. Coating formulation** | Dispersing the binder, repellent/enzyme, pigments and fillers into a homogeneous paint emulsion. | **In:** Binder, repellent, pigments, fillers.<br>**Out:** Formulated antifouling paint. |
| **4. Hull preparation** | Blast-cleaning the steel hull in drydock to bare metal to ensure coating adhesion. | **In:** Aged coating/rust, abrasive media.<br>**Out:** Blast-cleaned steel surface. |
| **5. Coating application** | Airless-spraying anticorrosive primer, tie-coat and final antifouling layers to the prepared hull. | **In:** Primer, tie-coat, antifouling paint.<br>**Out:** Multi-layer coated hull. |
| **6. In-service monitoring** | Tracking fouling accumulation and coating performance across voyages. | **In:** Coated hull, inspection/drag data.<br>**Out:** Fouling and fuel-efficiency performance record. |

Cross-cutting technologies of the sector:
- **Self-polishing copolymers (SPC):** polymer matrices that hydrolyze slowly and evenly under frictional shear in seawater, keeping a fresh, repellent-releasing surface exposed throughout a hull's service life.
- **Enzymatic antifouling barriers:** protease and galactosidase enzymes incorporated into the coating that degrade the protein adhesive barnacle larvae use to attach, preventing settlement without a biocide.
- **Biomimetic micro-texturing:** shark-skin- or lotus-leaf-inspired surface patterns that physically interfere with larval settlement and biofilm formation.

---

## US

The US focuses on biomimetic and enzymatic antifouling research, with the Navy as a leading institutional driver of durable, non-toxic hull-coating development.

### biomimetic surface texturing, Navy-funded R&D, non-toxic coating standards
- **Naval research funding:** the US Navy is a major funder of research into durable, non-toxic antifouling coatings for its fleet, driving work on biomimetic surface textures and enzymatic barriers as copper/TBT alternatives.
- **Biomimetic micro-texturing:** US-developed shark-skin-inspired micropatterned films are used to physically discourage bacterial biofilm formation and larval attachment without releasing any biocide.
- **Regulatory posture:** the EPA regulates antifouling paint biocides under FIFRA, pushing the market toward silicone foul-release and biological-repellent chemistries as copper-based paints face tightening restrictions.

---

## CN

China leads in coating deployment scale as home to the world's largest shipyards, while its marine research institutes develop lower-cost natural-repellent coating chemistries.

### large-scale shipyard deployment, seaweed/chitosan-based repellents, green-shipping standards
- **Institute of Oceanology, Chinese Academy of Sciences (Qingdao):** its Marine Corrosion, Fouling and Protection Materials research group has developed multifunctional protective coatings — including a photothermal superhydrophobic coating combining anti-icing and anti-corrosion functions for marine aluminum alloys, published in *Materials Today Physics* in 2026.
- **Shipyard scale:** China's shipyards apply antifouling coatings at the largest volume of any country, giving domestic natural-repellent formulations (seaweed-extract and chitosan-based) a large addressable retrofit and newbuilding market.
- **Green-shipping standards:** China's Ministry of Transport has introduced national green-shipping standards pushing shipowners toward low-VOC, heavy-metal-free coatings.

---

## EU

The EU is the commercial center of the antifouling coatings industry, driven by strict Biocidal Products Regulation (BPR) limits on copper-based paints in the Baltic and North Seas.

### BPR-driven silicone foul-release systems, self-polishing copolymer leadership, newbuilding integration
- **AkzoNobel (International, Netherlands):** launched the Intersleek 2120 silicone foul-release coating in 2026 and joined RightShip's Zero Harm Innovation Partners Program to advance safer, cleaner marine coatings.
- **Jotun (Norway):** markets the Seaquantum Ultra S self-polishing silyl-acrylate antifouling coating and unveiled its expanded Hull Performance Solutions (HPS 2.0) coating system in 2026.
- **Hempel (Denmark):** completed the first newbuilding application of its next-generation Hempaguard NB silicone hull coating in 2026, integrating it directly into the shipbuilding process with Maersk and Yangzijiang Shipyard rather than applying it only as a retrofit.

---

## Leading companies and research institutes

| Company / Institute | Country | Key products / platforms | Tech features | Status 2026 |
|:---|:---|:---|:---|:---|
| **AkzoNobel** | 🇳🇱 Netherlands | *Intersleek 2120* silicone foul-release coating | Biocide-free foul-release, 2026 launch | commercial |
| **Jotun** | 🇳🇴 Norway | *Seaquantum Ultra S*, HPS 2.0 | Self-polishing silyl-acrylate chemistry | commercial |
| **Hempel** | 🇩🇰 Denmark | *Hempaguard NB* silicone hull coating | First-ever newbuilding-stage application (2026) | commercial |
| **Institute of Oceanology, CAS** | 🇨🇳 China | Photothermal superhydrophobic protective coatings | Combined anti-icing/anti-corrosion marine coating research | research |

---

## Tech stack and innovations

The antifouling bio-coatings stack pairs a biologically derived active ingredient or surface pattern with a durable polymer delivery matrix.

1. **Self-polishing copolymer (SPC) matrices:**
   - A silyl-acrylate or silicone-based binder hydrolyzes at a controlled rate under seawater flow shear, continuously exposing fresh, repellent-releasing surface as the outer layer wears away.
   - This mechanism is what allows silicone foul-release systems like Intersleek and Seaquantum to maintain performance across multi-year drydocking intervals.
2. **Biomimetic surface texturing:**
   - Micro-scale surface patterns modeled on shark skin or lotus-leaf micro-roughness physically disrupt the settlement cues that algae spores and barnacle larvae rely on.
   - Because these surfaces work through geometry rather than chemistry, they avoid biocide-release regulatory hurdles entirely.
3. **Enzymatic and natural-repellent additives:**
   - Protease and galactosidase enzymes embedded in a coating degrade the protein adhesive barnacle larvae secrete, preventing attachment without a toxic biocide.
   - Natural repellents such as zosteric acid (from *Zostera marina* seagrass) and chitosan provide a biodegradable alternative to copper/organotin biocides.

---

## Value chains and production pipelines

### Industrial pipeline of self-polishing antifouling coating production and application

```
┌───────────────────────────┐      ┌───────────────────────────┐
│ 1. Repellent extraction    │ ───> │ 2. Copolymer synthesis     │
│    (e.g., zosteric acid)   │      │    (silyl-acrylate binder) │
└───────────────────────────┘      └───────────────────────────┘
                                                 │
                                                 ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 4. Hull blast-cleaning     │ <─── │ 3. Paint dispersion        │
│    (Sa3 standard)          │      │    (dissolver mixing)      │
└───────────────────────────┘      └───────────────────────────┘
              │
              ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 5. Airless spray           │ ───> │ 6. In-service fouling      │
│    application (drydock)   │      │    monitoring              │
└───────────────────────────┘      └───────────────────────────┘
```

#### Stage 1: Repellent extraction
Zosteric acid is extracted from *Zostera marina* seagrass by aqueous-alcohol extraction followed by crystallization, yielding the natural antifouling active ingredient.

#### Stage 2: Copolymer synthesis
A silyl-acrylate copolymer binder is synthesized in a polymerization reactor, engineered to hydrolyze at the rate needed for controlled, even release in seawater.

#### Stage 3: Paint dispersion
The copolymer binder, repellent, plasticizers and fillers are mixed in high-speed dissolvers until a homogeneous emulsion with sub-15-micron particle size is achieved.

#### Stage 4: Hull blast-cleaning
The vessel is drydocked and its steel hull is abrasive-blasted to bare metal (the Sa3 cleanliness standard), removing old coating and rust to ensure adhesion.

#### Stage 5: Airless spray application
An anticorrosive primer, a tie-coat, and the final antifouling layer are applied in sequence by airless spray equipment to a total dry-film thickness of roughly 150-200 micrometers.

#### Stage 6: In-service fouling monitoring
Hull condition and fouling accumulation are tracked across voyages, feeding back into fuel-efficiency and drag-performance data used to schedule the next drydocking.