PBAT STARCH
Additive grade
STARCH = starch-blend compound
Bio-content and cost-driven blend for shopping bags; faster composting but higher moisture sensitivity.
Values for the STARCH condition
Other PBAT grades and fills
PBAT is listed in 6 conditions; see the grade overview at PBAT.
Compare all 6 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Injection-moulding grade | Pick for injection-moulded cutlery, caps and toughening masterbatch where fill length matters more than melt strength. | 9 | 22 | 550 | 33 Shore D |
Extrusion-coating / paper-lamination grade | Chosen for compostable paper cup and lunchbox coating: low viscosity, good neck-in control and paper adhesion. | 10 | 25 | 600 | 32 Shore D |
UV-stabilised agricultural mulch-film grade | Stabilised (often carbon-black or HALS-modified) grade tuned for a controlled field life of one growing season. | 10 | 26 | 550 | 32 Shore D |
STARCHThis page Starch-blend compound | Bio-content and cost-driven blend for shopping bags; faster composting but higher moisture sensitivity. | 11 | 16 | 320 | 40 Shore D |
Mineral (CaCO₃ 20–40 %) filled compound | Lowest-cost compostable bag compound; stiffer and cheaper but loses tear strength and elongation. | 12 | 15 | 300 | 42 Shore D |
PLA/PBAT alloy compound (PLA-rich) | PBAT used as impact modifier in PLA-dominant compounds for stiffer bags, cutlery and thermoformed trays. | — | 32 | 180 | 62 Shore D |
What is PBAT STARCH?
PBAT STARCH is PBAT in the STARCH grade — bio-content and cost-driven blend for shopping bags; faster composting but higher moisture sensitivity. PBAT STARCH has a yield strength of 11 MPa (1.6 ksi) and a tensile strength of 16 MPa (2.32 ksi) — weaker than 89% of polymer grades. Elongation at break is 320% and the elastic modulus is 0.3 GPa (0.0435 Msi). PBAT STARCH has a density of 1.32 g/cm³ (0.0477 lb/in³), heavier than 72% of polymer grades. Its glass-transition temperature is -30°C (-22 °F).
Advantages
- Readily welded — 78/100, better than 84% of polymer grades
- Ductile — tolerates forming and impact — 320%, better than 82% of polymer grades
Limitations
- Absorbs moisture — dry before molding — 3%, worse than 99% of polymer grades
- Needs corrosion protection — 45/100, worse than 98% of polymer grades
- Limited service temperature — 50°C (122 °F), worse than 94% of polymer grades
- Low strength — 11 MPa (1.6 ksi), worse than 89% of polymer grades
- Difficult to machine — 30/100, worse than 87% of polymer grades
PBAT STARCH properties
Typical room-temperature values for PBAT STARCH; 27 are specific to this condition. Other listed values are PBAT reference data and may not represent this condition. Bars are the position among polymer grades.
Physical5
PBAT STARCH has a density of 1.32 g/cm³ (0.0477 lb/in³), heavier than 72% of polymer grades. Its glass-transition temperature is -30°C (-22 °F).
Mechanical9
PBAT STARCH has a yield strength of 11 MPa (1.6 ksi) and a tensile strength of 16 MPa (2.32 ksi) — weaker than 89% of polymer grades. Elongation at break is 320% and the elastic modulus is 0.3 GPa (0.0435 Msi).
Thermal10
PBAT STARCH is rated for continuous service to 50°C (122 °F). It conducts heat at 0.25 W/m·K (0.144 BTU/hr·ft·°F), better than 72% of polymer grades. Thermal expansion is 170 µm/m·K (94.4 µin/in·°F).
Electrical2
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 98% of polymer grades. UV resistance is poor.
Sustainability3
Producing a kilogram of PBAT STARCH takes about 75 MJ of energy and emits 4 kg of CO₂ — less than 91% of polymer grades. Typical recycled content is 0%.
Manufacturability7
PBAT STARCH's machinability is poor (30/100, worse than 87% of polymer grades); weldability very good (78/100); formability very good (72/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with PBAT STARCH
Is PBAT easy to machine?
Rarely machined — too soft and gummy; if needed use very sharp tools, high speed, low feed and chilled parts.
Can PBAT be welded?
Excellent heat sealability at 110–140 °C; ultrasonic and hot-bar sealing both work, and it seals well to PLA and coated paper.
Can PBAT be formed, bent or molded?
Dry 3–4 h at 60–70 °C before processing (hydrolysis risk), extrude at 155–190 °C with low shear; blown film runs at BUR 2.5–4 and drawdown below 10 µm on chain-extended grades.
What surface finishes work on PBAT?
Corona treat to 38–42 dyn/cm before flexo printing or lamination; use only compostable-certified inks/adhesives to keep EN 13432 / GB/T 38082 compliance.
PBAT chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| 1,4-butanediol (BDO) residuediol component, ~50 mol% of all repeat units | 30 – 38 | 34 |
| adipic acid residuealiphatic diacid; sets flexibility and biodegradation rate | 25 – 34 | 30 |
| terephthalic acid (PTA) residuearomatic diacid, ~44–50 mol% of diacid; gives strength and Tm | 30 – 40 | 36 |
| chain extender (e.g. epoxy/isocyanate typrocess additives; grade dependent | 0 – 1.5 | 0.5 |
PBAT STARCH — frequently asked
What is PBAT STARCH used for?
PBAT STARCH is typically used for compostable shopping bags, mulch film, food packaging film and PLA blend toughening agent. In short: toughest compostable film polyester; 650% elongation; PLA toughening additive.
What is the yield strength of PBAT STARCH?
PBAT STARCH has a typical yield strength of 11 MPa (1.6 ksi) and a tensile strength of 16 MPa (2.32 ksi) — weaker than 89% of polymer grades. Strength varies by condition: see the 6 listed tempers.
Is PBAT STARCH easy to machine?
Not especially — machinability is rated poor (30/100, worse than 87% of polymer grades). Rarely machined — too soft and gummy; if needed use very sharp tools, high speed, low feed and chilled parts.
Can PBAT STARCH be welded?
Yes — weldability is rated very good (78/100). Excellent heat sealability at 110–140 °C; ultrasonic and hot-bar sealing both work, and it seals well to PLA and coated paper.
What surface finishes work on PBAT STARCH?
Corona treat to 38–42 dyn/cm before flexo printing or lamination; use only compostable-certified inks/adhesives to keep EN 13432 / GB/T 38082 compliance.
Can PBAT STARCH be formed, bent or molded?
Dry 3–4 h at 60–70 °C before processing (hydrolysis risk), extrude at 155–190 °C with low shear; blown film runs at BUR 2.5–4 and drawdown below 10 µm on chain-extended grades.
What is the maximum service temperature of PBAT STARCH?
PBAT STARCH is rated for continuous use to about 50°C (122 °F), and briefly to 90°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ecoflex F Blend C1200 product information — BASF (2023)
- PBAT TH801T/TH803T — (Xinjiang Blue Ridge Tunhe) (2023)
- ASTM D6400 Standard Specification for Labeling of Plastics Designed to be Aerobically Composted — ASTM (2023)
- EN 13432 Packaging — Requirements for packaging recoverable through composting and biodegradation — CEN (2000)
- Handbook of Biodegradable Polymers (aliphatic-aromatic copolyesters chapter) — Wiley/De Gruyter (2020)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.