🧩 PHA – Polyhydroxyalkanoate
(Natural biodegradable material biologically produced by microorganisms during the fermentation of sugars or vegetable oils. PHA is a family of bio-polyesters offering mechanical performance similar to conventional plastics.)
🔹 What is PHA
PHA (Polyhydroxyalkanoate) is a biopolymer produced by bacteria as an energy reserve. At ReplastMD, we treat it as a highly versatile eco-material. Depending on the monomer composition, PHA can be rigid like PP or soft like TPE. It is 100% natural, biodegradable, and non-toxic, making it an excellent choice for interior automotive trim and flexible bio-gaskets.
🔧 Composition & Properties
- Polymer Base: Natural bio-polyester (PHA, PHB, PHBV, PHBH).
- Source: Bacterial fermentation (sugar, canola oil, palm oil).
- Density: 1.18 – 1.25 g/cm³.
- Melting Point: 100 – 180 °C.
- Operating Range: –20 °C to +90 °C.
- Chemical Resistance: Very good (oils, detergents, water).
🚗 Where PHA is used in the automotive industry
| Component | Example parts | Observations |
| Bio Gaskets & Shields | Covers, handles, plates | Flexible and compostable |
| Bio Interior Elements | Panels, inserts, decorations | Natural, glossy finish |
| Flexible Films | Protective layers, membranes | High elasticity |
| Eco Prototypes | Bio-testing, light components | Easily injectable and moldable |
🔧 Welding Temperature and Methods
| Method | Optimal Temp | Observations |
| Hot Air | ✅ 110 – 130 °C | Weldable, slow and clear melt |
| Heat Plate (Mirror) | ✅ 120 – 130 °C | Smooth, glossy bond |
| Manual Extrusion | ⚠️ 130 – 140 °C | Possible, but requires precise control |
| Chemical Bonding | ✅ Recommended | Bio-compatible polyester adhesives |
💡 ReplastMD Recommendation: PHA welds easily with hot air at 120 °C, but requires slow cooling to prevent stress cracking. For elastic parts, use low pressure and a compatible PHA or PBS welding rod.
🧠 How to Identify PHA
- Smooth, glossy, slightly rubbery texture.
- Color: Milky white, translucent, or yellowish.
- ReplastMD practical test: High elasticity with slow recovery; softens between 110–130 °C without visible smoke.
- Common markings: >PHA<, >PHB<, >PHBV<, >NODAX<, >MIREL<.