TPS
Native starch plasticized with glycerol/water and processed like a conventional thermoplastic; low cost and fully bio-based, typically blended with PLA/PBS/PHA to reduce cost and tune stiffness or degradation rate.
Reference datasheet — TPS is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
TPS grades and fills
TPS is supplied in 8 conditions, soft to hard.
Compare all 8 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Extruded starch foam | Water-steam expanded starch foam replacing EPS loose-fill and protective packaging; dissolves in water. | 0.08 | 0.1 | 8 | |
Soft / high-plasticizer TPS | Pick for flexible film, bags and cushioning where elongation matters more than stiffness. | 2 | 3 | 110 | 25 Shore D |
TPS/PHA blend (20–50% starch) | Choose where marine/soil biodegradation of the whole compound is required, accepting higher resin cost. | 16 | 18 | 12 | 65 Shore D |
TPS/PBAT compostable blend (30–60% starch) | The dominant commercial form — blown-film grade for shopping/compost bags and mulch film; starch cuts cost, PBAT gives toughness and water tolerance. | 20 | 350 | ||
TPS/PBS blend (20–50% starch) | Balanced stiffness/toughness compostable compound for injection-moulded tableware and thermoformed trays. | 20 | 25 | 90 | 58 Shore D |
Natural-fibre / cellulose reinforced TPS | Pick for stiffer, more dimensionally stable and less moisture-sensitive moulded parts (pots, trays, packaging inserts). | 20 | 4 | ||
Rigid / low-plasticizer TPS | Pick for injection-moulded rigid disposables (cutlery, trays) where stiffness matters and brittleness is acceptable. | 22 | 25 | 6 | 68 Shore D |
TPS/PLA blend (20–40% starch) | Pick when rigidity and clarity-free structural disposables are needed at lower resin cost than neat PLA. | 32 | 5 |
Supply forms, finishes and certifications
Ways TPS is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
FOOD | Food-contact / compostable-certified grade | Certification |
NATDefault | Natural / standard glycerol-plasticized TPS | Standard supply |
What is TPS?
Native starch plasticized with glycerol/water and processed like a conventional thermoplastic; low cost and fully bio-based, typically blended with PLA/PBS/PHA to reduce cost and tune stiffness or degradation rate. TPS has a density of 1.32 g/cm³ (0.0477 lb/in³), heavier than 72% of polymer grades. Its glass-transition temperature is 10°C (50 °F). TPS has a yield strength of 6 MPa (0.87 ksi) and a tensile strength of 8 MPa (1.16 ksi) — weaker than 94% of polymer grades. Elongation at break is 60% and the elastic modulus is 0.25 GPa (0.0363 Msi).
What is TPS used for?
- biodegradable shopping bags
- loose-fill packaging foam
- PLA/PBS cost-reduction blends
- agricultural mulch film
Advantages
- Low embodied carbon — 1.4 kg CO₂/kg, better than 99% of polymer grades
Limitations
- Needs corrosion protection — 20/100, worse than 100% of polymer grades
- Absorbs moisture — dry before molding — 35%, worse than 100% of polymer grades
- Low strength — 6 MPa (0.87 ksi), worse than 94% of polymer grades
- Limited service temperature — 50°C (122 °F), worse than 94% of polymer grades
- Hard to polish — 25/100, worse than 90% of polymer grades
TPS properties
Typical room-temperature values; bars are the position among polymer grades.
Physical7
TPS has a density of 1.32 g/cm³ (0.0477 lb/in³), heavier than 72% of polymer grades. Its glass-transition temperature is 10°C (50 °F).
Mechanical12
TPS has a yield strength of 6 MPa (0.87 ksi) and a tensile strength of 8 MPa (1.16 ksi) — weaker than 94% of polymer grades. Elongation at break is 60% and the elastic modulus is 0.25 GPa (0.0363 Msi).
Thermal11
TPS 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 150 µm/m·K (83.3 µin/in·°F).
Electrical5
TPS is an electrical insulator with a dielectric strength of 15 kV/mm (381 V/mil) and a resistivity of 1×10⁹ Ω·m.
Chemical & Environmental3
Corrosion resistance is poor (20/100), worse than 100% of polymer grades. UV resistance is fair.
Sustainability4
Producing a kilogram of TPS takes about 25 MJ of energy and emits 1.4 kg of CO₂ — less than 100% of polymer grades. Typical recycled content is 0%.
Manufacturability8
TPS's machinability is fair (40/100, worse than 82% of polymer grades); weldability good (65/100); formability very good (70/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the polymer family
Yield strength against density for every polymer grade FabDigit runs. TPS is highlighted; hover a dot for its name, or open the interactive family chart.
Working with TPS
Is TPS easy to machine?
Machines poorly — soft and gummy, absorbs coolant water; use sharp tools, high rake, dry cutting and light passes, and expect swelling/dimensional drift with humidity.
Can TPS be welded?
Heat-seals and hot-plate/ultrasonic welds at low temperature (110–150 °C); solvent bonding with water or aqueous adhesives is possible because of its hydrophilicity.
Can TPS be formed, bent or molded?
Extrude/inject at 110–170 °C melt with degassing (water vapour) and low back pressure; degradation and browning start above ~180 °C, so keep short residence time; blown film runs best in PBAT/PLA blends.
TPS 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 |
|---|---|---|
| starch (amylose+amylopectin, maize/potatdry basis; amylose 20–30% of starch typical | 55 – 80 | 68 |
| glycerol (plasticizer)may be partly replaced by sorbitol, urea, glycols | 15 – 35 | 25 |
| waterco-plasticizer; equilibrium content varies with RH | 3 – 15 | 6 |
| processing aids / emulsifier / lubricantlecithin, stearates, mono-glycerides | 0.5 – 3 | 1 |
What surface finishes work on TPS?
Water-based inks and coatings adhere well; a barrier lacquer or PBAT skin is usually needed to control moisture pickup; not paintable with solvent systems that dissolve the plasticizer.
How much does TPS cost?
TPS is a standard-cost polymer ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
TPS — frequently asked
What is TPS used for?
TPS is typically used for biodegradable shopping bags, loose-fill packaging foam, PLA/PBS cost-reduction blends and agricultural mulch film. In short: lowest-cost bio-based resin; fully compostable blend base; moisture-sensitive, low strength.
What is the yield strength of TPS?
TPS has a typical yield strength of 6 MPa (0.87 ksi) and a tensile strength of 8 MPa (1.16 ksi) — weaker than 94% of polymer grades. Strength varies by condition: see the 8 listed tempers.
Is TPS easy to machine?
Not especially — machinability is rated fair (40/100, worse than 82% of polymer grades). Machines poorly — soft and gummy, absorbs coolant water; use sharp tools, high rake, dry cutting and light passes, and expect swelling/dimensional drift with humidity.
Can TPS be welded?
Yes — weldability is rated good (65/100). Heat-seals and hot-plate/ultrasonic welds at low temperature (110–150 °C); solvent bonding with water or aqueous adhesives is possible because of its hydrophilicity.
What surface finishes work on TPS?
Water-based inks and coatings adhere well; a barrier lacquer or PBAT skin is usually needed to control moisture pickup; not paintable with solvent systems that dissolve the plasticizer.
Can TPS be formed, bent or molded?
Extrude/inject at 110–170 °C melt with degassing (water vapour) and low back pressure; degradation and browning start above ~180 °C, so keep short residence time; blown film runs best in PBAT/PLA blends.
What is the maximum service temperature of TPS?
TPS is rated for continuous use to about 50°C (122 °F), and briefly to 90°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does TPS cost?
TPS is a standard-cost polymer ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- Biodegradable Multiphase Systems Based on Plasticized Starch (Avérous, J. Macromol. Sci. Part C) — Taylor & Francis (2004)
- Materials and the Environment: Eco-Informed Material Choice — Butterworth-Heinemann (Ashby) (2021)
- Solanyl potato-starch biopolymer compounds — Rodenburg Biopolymers (2023)
- BIOPLAST starch-based compounds (film & injection grades) — BIOTEC GmbH (2023)
- Mater-Bi starch-based bioplastic family data — Novamont (2023)
- EN 13432 / GB/T 19277 compostability requirements — CEN / SAC (2011)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.