| Comparison Point | PLA (Example Data: Prusament PLA [a]) | PLA+ (Example Data: eSUN PLA+ [b]) |
|---|---|---|
| What The Label Usually Means | Standard PLA formulation with predictable behavior and wide profile support. | “PLA-based, modified” blend. The recipe varies by brand; “+” is not a universal spec. |
| Typical Nozzle Temperature | 210 ± 10 °C | 210–230 °C |
| Typical Bed Temperature | 40–60 °C | 45–60 °C |
| Cooling Fan | 100% | 100% |
| Suggested Print Speed | Up to 200 mm/s (profile-dependent) | 40–100 mm/s (profile-dependent) |
| Density | 1.24 g/cm³ | 1.23 g/cm³ |
| Heat Resistance (Declared HDT / Heat Distortion) | 55 °C (ISO 75, as declared) | 53 °C (GB/T 1634, as declared) |
| Tensile (Declared) | 57 ± 1 MPa (filament yield strength, ISO 527, as declared) | 63 MPa (tensile strength, GB/T 1040, as declared) |
| Flexural Strength (Declared) | 83–99 MPa (printed specimens, ISO 178, as declared) | 74 MPa (GB/T 1040, as declared) |
| Stiffness (Flexural Modulus, Declared) | 3.1–3.2 GPa (ISO 178, as declared) | 1973 MPa (≈1.97 GPa) (GB/T 9341, as declared) |
| Impact (Declared) | 13–14 kJ/m² (Charpy unnotched, ISO 179-1, as declared) | 9 kJ/m² (IZOD, GB/T 1843, as declared) |
| Elongation At Break (Declared) | 2.9–3.2% (yield elongation, ISO 527-1, as declared) | 20% (GB/T 9341, as declared) |
| Moisture Absorption (Declared) | 0.13% (24h, as declared) | Not declared in this sheet |
| Best Use Vibe | Clean surfaces, sharp details, predictable profiles. | More forgiving functional prototypes, slightly wider temp window, often tuned for toughness. |
PLA+ is a label, not a single material standard. One brand’s “+” can behave almost like classic PLA, another can feel closer to “tough PLA.” The real difference shows up in additives, declared test methods, and the print profile the maker targets.
PLA and PLA+ sit in the same comfort zone for most FDM printers, but they don’t always act like twins. PLA is the familiar baseline. PLA+ is usually a PLA-based blend tuned for a different balance of stiffness, layer bonding, and “how easily it prints” under real-world settings. If you only remember one thing, make it this: the label is less important than the datasheet and how the filament behaves in your printer.
Table of Contents
🧩 Names and Labels: PLA vs PLA+
PLA is polylactic acid: a common thermoplastic used in FDM because it’s stable, predictable, and usually easy to dial in. Most slicers and printer vendors treat PLA as the default “starter” profile.
PLA+ is typically a PLA-based blend marketed to deliver a different feel—often more ductile (less likely to snap), sometimes with improved layer bonding, and sometimes with a wider temperature window. The key detail: PLA+ has no universal definition. Two PLA+ spools from different brands can be genuinely different materials.
If you want a practical way to read “PLA+” without overthinking it: treat it as “PLA, but tuned.” Tuned for what? That’s where the datasheet (or at least the recommended temperature range) becomes your anchor.
🧪 What Actually Changes in PLA+
When a manufacturer tries to make PLA feel “stronger” or more reliable for functional parts, they usually adjust the polymer system rather than inventing a whole new filament family. PLA+ blends often involve some combination of the ideas below.
🧷 Impact Modifiers
These are additives or secondary polymers that increase toughness so the part absorbs energy instead of cracking. The trade-off can be lower stiffness, which shows up as more “give” under load.
🧬 Chain Extenders / Processing Aids
These are used to stabilize melt behavior and reduce issues like brittle filament or inconsistent extrusion. The goal is often smoother flow and better layer fusion at speed.
🧊 Crystallization Tuning
Some blends push PLA to crystallize a bit more (or differently) during and after printing. This can shift how parts behave around warm temperatures, but the effect depends heavily on print settings and geometry.
One example of a “PLA+ style” product is marketed as a PLA with engineering-like balance (toughness plus rigidity) and declares a glass transition around 62 °C in its published data. [c]
📌 Properties That Matter (and Why They Feel Different)
For everyday printing, “stronger” is too vague. The feel difference between PLA and many PLA+ blends usually comes down to a few specific properties. Here’s how to read them without turning your brain into a spreadsheet.
- Stiffness (Modulus)
- Higher modulus = part flexes less. Many PLA+ blends aim for toughness, and toughness often costs a bit of stiffness. That “slightly rubbery” feel in some PLA+ is real.
- Toughness (Impact / Elongation)
- Higher impact values or higher elongation can mean the part survives drops and shocks better. Some PLA+ sheets show much higher elongation than classic PLA examples, which usually translates to less brittle failure.
- Heat Behavior (HDT, Vicat, Tg)
- PLA parts typically start getting “soft-ish” around the same temperature neighborhood that many datasheets show as ~50–60 °C. The fine print matters: the test load, the method, and the print orientation change the story.
- Layer Bonding
- This is the quiet one. A blend that fuses layers more readily can feel “stronger” even if the base polymer isn’t wildly different—especially when you load the part across layer lines.
🧠 A Small Warning About “MPa”
Strength numbers are meaningful only when you know how they were tested. Tensile testing standards specify specimen shape, conditioning, and test speed, because plastics are sensitive to those details. [f]
🖨️ Printing Behavior: Where You’ll Notice the Difference
Most of the time, PLA and PLA+ will both give you clean prints. The difference shows up in temperature sensitivity, stringing behavior, and how forgiving the filament is when you push speed or cooling.
🌡️ Temperature Window
A practical baseline from a major printer vendor’s PLA guidance is that PLA prints at moderate temperatures, commonly around 200–210 °C depending on nozzle size and profile. [e]
- PLA: often looks great when you keep it cool enough for sharp details, but warm enough for consistent layer fusion.
- PLA+: many brands nudge the range upward, and that extra heat can improve interlayer bonding—especially on thicker walls and functional parts.
🧵 Stringing and Gloss
PLA tends to show stringing when it’s too hot for your retraction and cooling setup. PLA+ can be similar, but some blends tolerate higher temps without turning into a cobweb factory. If you see hair-like strings, lower temperature a bit or increase cooling—not both at the same time unless you’re sure.
🧱 Overhangs and Detail
Classic PLA is famous for crisp corners. PLA+ sometimes trades a touch of sharpness for layer bonding, especially if you run it hotter. If your model is all about tiny features, cooler PLA can still be the cleanest look.
Good default logic: start with the manufacturer’s range, then only move one variable at a time—temperature first, then cooling, then speed. That keeps the tuning honest.
🔥 Heat Reality: The “It Softens” Zone
People often expect PLA+ to be “heat resistant.” Sometimes it is. Often it isn’t—at least not in the way ABS/ASA users mean it. Many published examples for both PLA and PLA+ still sit around the mid-50s °C neighborhood for heat distortion style numbers (with the exact method and load spelled out in the datasheet).
- What that feels like: parts can start to relax, creep, or warp when they live in warm environments (think near motors, inside hot enclosures, or in direct sun through glass).
- What helps: thicker walls, ribs, and designing for load paths often improves real-world performance more than switching from PLA to a random “PLA+” spool.
- When PLA+ helps: blends that fuse layers better can keep shape under moderate load longer, even if the headline HDT isn’t dramatically higher.
If heat performance is the main goal, treat declared HDT/Vicat/Tg as your filter. If a PLA+ brand doesn’t publish heat data, assume it behaves close to PLA until proven otherwise by testing.
🔧 Strength and Layers: The Real “Upgrade” Area
In real prints, failures often happen between layers, not through solid material. That’s why many PLA+ blends feel “better” for brackets, clips, and parts that take knocks. It’s less about a magic tensile number and more about how the filament welds itself during extrusion.
PLA vs PLA+ (Typical Tendencies, Not Absolute)
PLA+ vs PLA (Typical Tendencies, Not Absolute)
🧷 What to Watch For in Real Parts
- Clean layer lines but brittle snap: often classic PLA behavior under impact; PLA+ blends may reduce this by allowing more deformation before failure.
- Layer-splitting: can improve with slightly higher temperature, slower outer walls, and choosing a PLA+ that is tuned for interlayer adhesion.
- Flexy feeling: not always bad. Some parts need give. But if you want rigid fixtures, classic PLA (or a rigid PLA formulation) can be the better tool.
📦 Storage and Drying: Keep the Baseline Stable
PLA is often described as easy, but moisture still matters. Wet filament can show up as popping, inconsistent extrusion, surface roughness, and stringing that feels “impossible” to tune.
🧴 What “Dry” Means in Data Terms
A PLA resin technical sheet highlights that drying prior to processing is essential, and gives a concrete target like keeping moisture content below 0.025% (250 ppm), with an example drying condition of 4 hours at 80 °C (plus dry air/dew point guidance). [d]
Filament spools aren’t identical to raw resin pellets, and spool drying temperature limits depend on the brand and the spool itself. Still, the takeaway is clean: control moisture and a lot of “mystery print problems” disappear.
- Seal it: airtight bag or box, desiccant inside, minimal open-air time.
- Track it: label the bag with the date you opened the spool and the room humidity if you know it.
- Dry it when symptoms appear: stringing spikes, bubbles, rough surfaces, random under-extrusion.
Quiet advantage: a dry spool makes your PLA vs PLA+ decision clearer, because you’re comparing materials—not moisture.
🎯 Choosing by Use Case (Without the Hype)
✅ When PLA Is a Great Pick
- Visual models where surface finish and crisp edges matter.
- Parts that live indoors and avoid warm environments.
- Fast iteration prints where you want predictable profiles and low drama.
- Dimensional accuracy work (especially with strong cooling and sensible speeds).
✅ When PLA+ Often Makes Sense
- Functional prototypes where impact and “oops moments” happen.
- Clips, brackets, and handles where a bit of ductility is useful.
- Projects pushed toward higher speed printing, where a tuned melt flow helps.
- When classic PLA feels brittle in your climate or your part geometry.
If you’re choosing between two specific spools, compare declared temperatures, impact/elongation, and any published heat numbers. Those three usually predict the “real difference” better than the marketing name.
❓ FAQ
Is PLA+ always stronger than PLA?
Not always. PLA+ is usually tuned for a different balance—often more toughness or better layer bonding. Some PLA+ blends can be less stiff than classic PLA, even if they feel “harder to break.” Compare declared test methods and properties instead of assuming the plus sign means higher everything.
Do I need different slicer profiles for PLA+?
Often you can start from a PLA profile and adjust temperature first. Many PLA+ filaments like a slightly higher nozzle temperature and sometimes a slightly warmer bed. Cooling is usually still high, but the best balance depends on your printer’s airflow and the part geometry.
Why does PLA+ sometimes look less crisp on tiny details?
If you print PLA+ hotter to improve layer fusion, the melt can stay fluid longer, rounding micro-edges slightly. Dropping temperature a bit, increasing cooling, or slowing outer walls can bring back sharpness.
Can PLA+ handle heat better than PLA?
Sometimes, but not by default. Many published examples for both PLA and PLA+ still sit in a similar heat-softening neighborhood. If heat is the main goal, look for published HDT/Vicat/Tg data for the specific filament, or move to a material family designed for heat performance.
Does PLA+ reduce layer splitting?
It can. Many PLA+ blends are formulated to improve layer fusion and toughness. You still get the biggest gains by combining the right filament with the right settings: adequate nozzle temperature, reasonable cooling, and not pushing speed past what your hotend can melt consistently.
If I want reliable functional parts, should I jump straight to PLA+?
If your classic PLA parts feel brittle or fail at layer lines, PLA+ is a sensible next step because it often improves toughness with minimal workflow change. If your functional parts live in warm environments, the decision should be based on heat ratings rather than the “+” label.
Sources
- Prusament PLA by Prusa Polymers — Technical Datasheet (PDF): https://prusament.com/wp-content/uploads/2022/10/PLA_Prusament_TDS_2021_10_EN.pdf
- eSUN PLA+ Filament — Technical Data Sheet V4.0 (PDF): https://www.esun3d.com/uploads/eSUN_PLA%2B-Filament_TDS_V4.0.pdf
- Polymaker — PolyLite™ PLA Pro (Thermal & Physical Properties Page): https://wiki.polymaker.com/polymaker-products/more-about-our-products/documents/technical-data-sheets/pla/polylite-tm-pla-pro
- NatureWorks — Ingeo™ Biopolymer 4043D Technical Data Sheet (PDF): https://www.natureworksllc.com/~/media/Technical_Resources/Technical_Data_Sheets/TechnicalDataSheet_4043D_films_pdf.pdf
- UltiMaker Support — How to Print with UltiMaker PLA: https://support.ultimaker.com/s/article/1667337611872
- ASTM D638 (Educational Copy Hosted by Virginia Tech) — Tensile Properties of Plastics (PDF): https://borgoltz.aoe.vt.edu/aoe3054/manual/expt5/D638.38935.pdf