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PLA vs PTMT

Polymer · grade comparison

PLA and PTMT are both polymer grades. PTMT is the stronger of the two: yield strength 55 MPa (7.98 ksi) against 48 MPa (6.96 ksi) for PLA, about 15% more; tensile strength follows at 55 MPa (7.98 ksi) vs 50 MPa (7.25 ksi). PTMT is the more ductile: elongation 100% versus 5% for PLA. PLA is lighter (1.24 g/cm³ vs 1.31 g/cm³ for PTMT) and PLA is stiffer (3.4 GPa vs 2.6 GPa). On the shop floor, PLA sits in a lower cost tier (budget, $) than PTMT (standard, $$).

PLAChoose it when weight is the constraint, or when cost is the deciding factor.

PTMTChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

PLA vs PTMT: properties

PLAPTMT

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

3.4 GPa0.49 Msi
2.6 GPa0.38 Msi

Shear Modulus

1.3 GPa0.18 Msi
0.95 GPa0.14 Msi

Poisson's Ratio

0.36
0.4

Tensile Strength (Ultimate)

50 MPa7.3 ksi
55 MPa8 ksi

Yield Strength (0.2% offset)

48 MPa7 ksi
55 MPa8 ksi

Elongation at Break

5%
100%

Compressive Strength

70 MPa10.2 ksi
85 MPa12.3 ksi

Compressive Modulus

3.2 GPa0.46 Msi
2.4 GPa0.35 Msi

Flexural Strength

83 MPa12 ksi
88 MPa12.8 ksi

Flexural Modulus

3.5 GPa0.51 Msi
2.4 GPa0.35 Msi

Fracture Toughness (K_IC)

2.2 MPa·√m2 ksi·√in
—

Izod Impact, Notched

22 J/m0.41 ft·lbf/in
50 J/m0.94 ft·lbf/in

Hardness, Shore D

83 Shore D
82 Shore D

Hardness, Rockwell R

105 HRR
118 HRR

Hardness, Rockwell M

—
70 HRM

Same in both: Bulk Modulus 4 GPa0.58 Msi · Shear Strength 45 MPa6.5 ksi

Physical

Density and transition temperatures.

Density

1.24 g/cm³0.04 lb/in³
1.31 g/cm³0.05 lb/in³

Melting Temperature (Tm)

160°C320 °F
225°C437 °F

Glass Transition (Tg)

60°C140 °F
50°C122 °F

Water Absorption (24 h)

0.3%
0.08%

Water Absorption (Saturation)

1%
0.45%

Refractive Index

1.46
1.58

Light Transmission

88%
—

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

0.13 W/m·K0.08 BTU/hr·ft·°F
0.23 W/m·K0.13 BTU/hr·ft·°F

Specific Heat Capacity

1,800 J/kg·K0.43 BTU/lb·°F
1,500 J/kg·K0.36 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

70 µm/m·K38.9 µin/in·°F
80 µm/m·K44.4 µin/in·°F

Max Service Temperature (continuous)

50°C122 °F
120°C248 °F

Min Service Temperature

-20°C-4 °F
-40°C-40 °F

Heat Deflection Temp. @ 0.45 MPa

55°C131 °F
150°C302 °F

Heat Deflection Temp. @ 1.8 MPa

50°C122 °F
60°C140 °F

Vicat Softening Point (B50)

58°C136 °F
178°C352 °F

Limiting Oxygen Index

20%
21%

Max Service Temperature (short-term)

65°C149 °F
160°C320 °F

Electrical

Conductivity and insulation.

Dielectric Strength

19 kV/mm483 V/mil
22 kV/mm559 V/mil

Dielectric Constant (1 MHz)

3
3.1

Dissipation Factor (1 MHz)

0.013
0.018

Surface Resistivity

1×10¹⁶ Ω
1×10¹⁵ Ω

Comparative Tracking Index (CTI)

—
600 V

Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Volume Resistivity 1×10¹⁶ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

55 / 100
78 / 100

UV / Weathering Resistance

40 / 100
35 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

60 / 100
68 / 100

Formability (cold)

25 / 100
30 / 100

Polishability

55 / 100
45 / 100

Mold Shrinkage

0.4%
1.7%

Melt Flow Rate

6 g/10 min
25 g/10 min

Processing Melt Temperature (typ.)

205°C401 °F
255°C491 °F

Mold Temperature (typ.)

55°C131 °F
70°C158 °F

Same in both: Weldability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

50 MJ/kg21,496 BTU/lb
95 MJ/kg40,843 BTU/lb

Embodied Carbon (primary production)

1.8 kg CO₂/kg
4.4 kg CO₂/kg

Embodied Water

350 L/kg41.9 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

2%
5%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

40 kN·m/kg
42 kN·m/kg

Specific Stiffness (E / density)

2.7 MN·m/kg
2 MN·m/kg

Modulus of Resilience

339 kJ/m³
582 kJ/m³

Same in both: Thermal Diffusivity 0.1 mm²/s · Thermal Shock Resistance Index 0

Strength versus weight

Yield strength against density for every polymer grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

0.1110100123Density (g/cm³)Yield strength (MPa) — log scalePTMTPLA

Manufacturing and finishing

CapabilityPLAPTMT
3D printingYes—
Default conditionStandard—
Relative cost$ Budget$$ Standard
Min. machined wall——
Best machined surface——
Conductive CoatingYes—
Dyeing (Nylon)Yes—
EMI Shielding CoatingYes—
PaintingYes—
Primer CoatingYes—
Soft Touch CoatingYes—
Tinted CoatingYes—
UV CoatingYes—
Vacuum MetallizationYes—
Waterproof CoatingYes—

PLA vs PTMT — frequently asked

Is PTMT stronger than PLA?

Yes. PTMT has a typical yield strength of 55 MPa (7.98 ksi) against 48 MPa (6.96 ksi) for PLA — about 15% more. Tensile strength is 55 MPa (7.98 ksi) vs 50 MPa (7.25 ksi).

Which is cheaper, PLA or PTMT?

PLA is the lower-cost material: it sits in the budget tier ($) while PTMT is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, PLA or PTMT?

PTMT, by a small margin. Both rate good for machinability — 68/100 against 60/100 for PLA.

Ready to make it?

Upload a CAD file and FabDigit prices the part in PLA and PTMT side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.