EcoVid 80TFH High Heat Wood Filled Ingeo PLA is a melt-compounded thermoplastic compound based on poly(lactic acid) supplied under the Ingeo brand, filled with lignocellulosic wood flour, and modified with a heat-resistance package. The product is supplied in pellet form and is intended for injection molding, sheet extrusion, thermoforming, and large-format additive extrusion where a renewable wood-filled aesthetic must survive elevated short-duration service temperatures. The model designation 80TFH does not, by itself, define filler mass fraction, particle size distribution, melt flow rate, or additive percentage; those parameters must be taken from the lot-specific certificate of analysis. Published data for this exact formulation is limited, and the property and processing information below is therefore aggregated from publicly reported high-heat wood-filled PLA compound classes and analogous Ingeo PLA grades. It must be confirmed against developer data before specifying the product.

At the compounding level, high-heat wood-filled PLA is typically produced on a co-rotating twin-screw extruder having an L/D ratio of 40:1 or greater. Wood flour is introduced downstream through a side stuffer to limit total heat history. The melt temperature is held below 220 °C because PLA undergoes thermal depolymerization and lignocellulosic filler darkens above this threshold. The screw configuration generally places dispersive kneading blocks of 30° to 60° stagger upstream of the side stuffer to distribute the heat-resistance masterbatch. Downstream of the side stuffer, low-shear distributive elements control filler wetting without excessive fiber degradation. Melt pressure before the screens and screw torque are monitored as indirect indicators of filler dispersion. Torque instability on production-scale equipment is often caused by wood-flour moisture drift or particle-size distribution shifts, not by normal lot-to-lot variation in the base resin.

Processors should treat this material as shear-thinning and thermally sensitive. The melt mass-flow rate of comparable high-heat wood-filled PLA compounds, measured according to ISO 1133-1:2022 at 210 °C with a 2.16 kg load, typically falls in the 3–12 g/10 min range. Standard wood-filled PLA grades are often one to two MFR classes higher because they lack the higher-viscosity heat-resistant backbone. Capillary rheometry according to ISO 11443 is recommended for mold-filling simulation rather than reliance on a single MFR point. Because the compound is shear-thinning, increasing injection speed reduces apparent viscosity, but imposed shear heating can drive the melt above 220 °C in the gate region if fill speeds are aggressive.

Drying is mandatory and specific. Residual moisture before melt processing should be below 0.025% by weight, verified by Karl Fischer titration according to ISO 15512. A desiccant dryer operating at 60–80 °C for 4–6 h with a dew point of −40 °C or lower is the baseline starting condition. Storage at relative humidity above 60% requires re-drying. Opened bags should be consumed within 8 h of hopper exposure unless a heated hopper dryer is in use. Moisture excursions produce silver streaking, splay, and molecular-weight loss in the molded part, and they cannot be compensated solely by raising barrel temperature.

What processing limits emerge when wood-filled high-heat PLA enters a melt stream?

Barrel temperature profiles are staged from 170 °C at the feed throat to 200–210 °C at the nozzle. Melt residence time at 210 °C should not exceed 5 min; longer residence times produce measurable viscosity loss and acetic acid evolution. Mold temperature determines the thermal performance outcome. If the mold is operated at 25–40 °C, the part remains largely amorphous and the expected high-heat deflection temperature will not develop. When the high-heat designation is being exploited, mold temperatures of 60–100 °C are used to promote PLA crystallization. Mold-temperature tolerances should be maintained within ±5 °C unless a wider band is validated, because small fluctuations shift cooling rate and can produce differential shrinkage and inconsistent heat deflection.

Clamp force sizing for injection molding can be based on a cavity-pressure estimate of 30–50 MPa for filled PLA. Injection speed should be selected to avoid excessive gate shear heating; thin-wall parts below 1 mm require spiral-flow or cavity-fill validation before tool cutoff because published data for this exact formulation is limited. Hydraulic back pressure in the 0.3–1.0 MPa range is typical to maintain melt-density consistency without excessive screw recovery time. A reverse-taper or smear-tip check ring may be required for consistent shot volume because wood-filled PLA can clog standard ring checks if clearance is too tight. Screw and barrel wear is higher than with unfilled PLA; bimetallic barrels, hardened screws, and wear-resistant gate inserts are recommended for sustained production runs.

Heat deflection temperature, Vicat softening, and crystallinity

For this class, heat deflection temperature under 0.45 MPa load, tested according to ISO 75-2:2013 Method B, is typically 85–115 °C after high-mold-temperature processing or post-mold annealing. The corresponding value for unfilled amorphous PLA is generally below 60 °C. Under 1.8 MPa load, measured by ISO 75-2:2013 Method A, the high-heat wood-filled class typically falls between 60 °C and 85 °C. Vicat softening temperature, determined with 50 N load and 50 °C/h heating rate according to ISO 306, commonly falls between 95 °C and 125 °C. These are class values, not guaranteed specifications. Differential scanning calorimetry according to ISO 11357-3 should be used to confirm crystallinity after molding; the elevated heat deflection temperature is not a function of filler addition alone.

Post-mold annealing can be applied at 80–110 °C for 1–4 h to raise crystallinity and heat deflection temperature. Annealing fixtures are required because a wood-filled part softens and distorts if unsupported during the cycle. Annealing time depends on wall thickness; a cycle that stabilizes a 3 mm wall may over-anneal a 1 mm wall and darken the wood filler. Dimensional change during annealing must be allowed for in mold design; otherwise post-mold shrinkage will push the finished part outside its dimensional tolerance.

Filler loading and coupling chemistry alter the flexural-to-impact balance

At a given wood flour mass fraction, tensile modulus increases relative to neat PLA, while tensile strength and notched impact strength generally decrease. Coupling agents such as maleated PLA or aminosilane-treated wood flour improve filler-matrix adhesion, raising flexural modulus and strength; however they raise melt viscosity and require tighter temperature control. Notched Charpy impact strength, measured per ISO 179-1/1eA at 23 °C, is commonly reported between 1.5 kJ/m² and 4.5 kJ/m² for wood-filled PLA. Unnotched impact is higher but sensitive to wood-particle orientation. Flexural modulus often falls between 3.0 GPa and 7.0 GPa, depending on filler mass fraction and coupling-agent dose. If the compound contains a higher fine-mesh wood fraction, tensile strength may improve, but water uptake also increases because specific surface area rises.

Mesh distribution is a significant lot-to-lot variable. Fine-mesh wood flour produces a more uniform surface appearance and smoother extrudate, while coarse-mesh particles can increase visible wood specks but may reduce water uptake. Sieve analysis of the filler, such as ISO 3310-1, should be requested from the compounder when surface finish is a controlling specification. A shift in particle size without a corresponding change in melt flow rate can still alter gate freeze, warpage, and mechanical properties, so incoming inspection should combine sieve data with MFR and moisture content.

Compared with conventional wood-filled PLA, the high-heat class shifts the use boundary toward elevated-temperature interior and nonstructural components, but it narrows the melt-processing window. Standard wood-filled PLA can often be processed at 180–200 °C melt temperature; the high-heat variant typically requires 190–210 °C and closer moisture control. The tolerance for temperature deviation can be as narrow as ±5 °C when maximum crystallinity is targeted. Deviation outside this band does not necessarily produce visible defects, but it can lower heat deflection temperature and increase the spread of molded-part dimensions.

When EcoVid 80TFH is evaluated against neat high-heat PLA and petroleum-based wood composites

Differences from neat high-heat PLA are primarily rheological, dimensional, and aesthetic. Wood filler reduces volumetric mold shrinkage relative to unreinforced PLA; unfilled semicrystalline PLA can shrink in the range of 0.3–0.5% measured by ISO 294-4, whereas wood-filled PLA compounds typically exhibit 0.1–0.3% mold shrinkage. The reduction in shrinkage reduces warpage in large-area parts but increases melt viscosity and abrasive wear on screws, barrels, and hot-runner components. The wood-filled surface is also matte and less likely to show fingerprint marking than neat PLA. Compared with petroleum-based wood-polymer composites, the Ingeo PLA matrix contains bio-based carbon that may be characterized by ASTM D6866 Method B. The high-heat PLA matrix also softens more sharply above its heat deflection temperature than polypropylene-based wood composites; continuous service above 85 °C should be validated by component testing because thermal deformation is time-dependent.

Adhesive bonding and coating require surface preparation. Wood-filled PLA surfaces can carry dust from machining and low-molecular-weight species from processing. Isopropanol wiping and plasma or corona treatment improve paint adhesion; paint systems should be tested according to ASTM D3359 or the end-user specification. Mechanical fastening is preferred over structural adhesive bonding unless the adhesive is validated for polylactic acid and wood-filled thermoplastics. Published data for this specific configuration in painted or bonded assemblies is limited, so prototype testing under the actual assembly load is required.

The regulatory status of the product must not be assumed. The Ingeo PLA base resin may be manufactured to meet EU Regulation 10/2011 and FDA 21 CFR 177.1520 for certain food-contact grades, but wood filler, heat-resistance modifiers, and the final compounded material require separate validation. RoHS directive 2011/65/EU compliance for lead, cadmium, mercury, hexavalent chromium, PBBs, and PBDEs is not automatic and must be confirmed by a mill certificate. Industrial compostability to EN 13432 or ASTM D6400 must not be assumed for high-heat modified and wood-filled grades; certification depends on the heat-resistance package and filler chemistry. No UL 94 flame-retardant classification is assigned unless a certified report exists; high heat deflection temperature is not a flame-resistance indicator.

Extended outdoor exposure, especially in direct UV and high humidity, is not recommended for unmodified wood-filled PLA because the lignocellulosic filler can absorb moisture and the PLA matrix can hydrolyze. Components intended for outdoor service require moisture-barrier coatings, UV stabilizers, or systematic weathering validation according to ISO 4892-2 or ISO 4892-3. Published data for this exact EcoVid 80TFH formulation in long-term outdoor service is limited, and field validation under the intended service conditions is required before load-bearing or safety-critical specification.