🧩 PP+BIO – Biocomposite Polypropylene
(Eco-friendly weldable plastic, made with natural fillers, used in lightweight and sustainable automotive parts)
🔹 What is PP+BIO
PP+BIO is a biocomposite polypropylene, a material where standard PP is blended with natural fibers (hemp, flax, sisal, wood, cellulose) or partial biopolymers.
The goal of this combination is to achieve a plastic that is lighter, more eco-friendly, and has a lower carbon footprint, without compromising mechanical strength. It is an increasingly popular material in the automotive industry for panels, trims, and interior components due to its natural appearance and low weight.
🔧 Composition
- PP (Polypropylene) – base matrix
- BIO filler – vegetable fibers (10–40%) or biopolymers (PLA, PBS)
- Additives – coupling agents, antioxidants, UV stabilizers
- Variants: PP+BIO10, PP+BIO20, PP+BIO30
🚗 Where PP+BIO is used in the automotive industry
| Component | Example parts | Observations |
| Interior | Door panels, trims, decorative dashboard | Natural texture, matte finish |
| Body / Exterior | Covers, eco-friendly mudguards | Rigid, but lighter than classic PP |
| Engine Compartment | Acoustic covers, non-structural parts | Moderate heat resistance |
| Other Applications | Sustainable elements and recyclable parts | Low weight, natural appearance |
🔧 Welding temperatures and methods
| Method | Optimal temperature | Observations |
| Hot air | 250 – 270 °C | Welds easily, but fibers can blacken if overheated |
| Heat plate (mirror) | 240 – 260 °C | Clean and controlled bonding |
| Manual extrusion | 230 – 250 °C | For thin parts or trims |
| Ultrasonic | — | Rarely used, industrial only |
🔩 What to weld PP+BIO with (Material compatibility)
Many ask “what to weld PP+BIO with” — being a polypropylene modified with natural fibers, compatibility depends on the base matrix (PP). The material only welds with PP or PP+BIO with similar filler proportions.
✅ Compatible:
- PP+BIO ↔ PP+BIO – ideal combination
- PP+BIO ↔ PP-C / PP-H – good compatibility
- PP+BIO ↔ PP-TD / PP-MD – compatible, but different shrinkage
- PP+BIO ↔ PP+EPDM / PP+TPO – partially compatible
❌ Incompatible:
- PE, ABS, ASA, PC, PA, PVC – different chemistry, will not bond
💡 ReplastMD Recommendation:
Use original PP-BIO or PP-C welding rods at a temperature of 260–270 °C. Avoid overheating — natural fibers can carbonize above 280 °C, affecting the visual appearance.
🏭 Manufacturers and trade names
| Manufacturer | Brand / Series | Country / Region |
| Borealis | Daplen® Bio Series | Austria |
| LyondellBasell | Hostacom® Eco | Germany / Netherlands |
| SABIC | PP Bio-based Compound | Netherlands / Global |
| TotalEnergies | Lumicene® Bio | France |
| Trinseo | Biolen® PP | EU |
🧠 How to identify PP+BIO
- Engraved marking: >PP-BIO<, >PP-NF< (natural fiber) or >PP-WF< (wood fiber)
- Matte surface, natural texture, slightly rough
- Yellow-blue flame, paraffin and burnt wood smell
- Melts at 260 °C, no bubbles
- Density slightly higher than simple PP
🛠️ PP+BIO Welding at ReplastMD:
At our service center in Chisinau (Ciocana sector), ReplastMD performs professional PP-BIO welding for:
- eco-friendly panels, covers, and trims
- interior parts made from natural composites
- restoration of mounts and broken zones