EcoVid 30GBIM General Purpose High Molecular Weight Ingeo PLA is an unfilled polylactide resin specified for general-purpose extrusion and injection molding operations where melt strength and molecular weight retention are the limiting variables. The product designation places it in the high-molecular-weight portion of the Ingeo PLA family, with a lower melt flow rate than standard general-purpose injection grades. Because a product-specific public datasheet for this model is not available, the technical boundaries in this discussion are drawn from high-molecular-weight Ingeo PLA reference data and should be confirmed against the supplier lot certificate. Comparable high-MW Ingeo PLA resins typically exhibit a melt flow rate of 2–10 g/10 min at 210 °C under 2.16 kg load when tested according to ISO 1133-1:2022. Solid density is generally 1.24 g/cm³ under ISO 1183-1:2019. The resin is neither a high-flow thin-wall injection grade nor an impact-modified ductile PLA; its differentiation lies in higher extensional viscosity, reduced edge neck-in during cast film processing, and greater tolerance for melt-phase drawing operations.

In production-scale cast film and sheet operations, high-molecular-weight PLA resins are used when edge neck-in, bubble sag, or draw resonance limit line speed. On three-layer cast film dies with lip gaps of 0.4–0.8 mm, the 30GBIM molecular architecture is expected to provide extensional viscosity above that of low-viscosity Ingeo PLA. Single-screw extruders with grooved feed sections and L/D ratios between 24:1 and 30:1 should be fed with positive displacement rather than flood feeding to prevent screw slip and melt-pressure oscillation. Barrel temperature set points from 170 °C at the feed zone to 210 °C at the metering zone, with a die temperature of 195 °C, are commonly used starting references for high-MW PLA. Melt temperature should not exceed 240 °C because poly(L-lactide) thermal degradation proceeds through unzipping and random chain scission; lactide vapor appears as condensate on vacuum vents. Published data for this specific 30GBIM configuration is limited, so initial production trials should include rheological characterization of the as-received pellets and a purge protocol using lower-viscosity PLA at 200 °C to remove shear-degraded boundary layers from the die land.

What Moisture Uptake Limits Are Relevant Before Melt Processing?

Ingeo PLA resins are hygroscopic and undergo melt-state hydrolysis at free moisture above 250 ppm. Drying in a desiccant-bed dryer at 80 °C for 4 h is required when ambient relative humidity exceeds 60%; the drying air dew point should be at or below −40 °C. Residual moisture is measured by Karl Fischer titration or by a moisture analyzer following ISO 15512:2019. On twin-screw extruders with L/D 30:1 operating from 180 °C to 210 °C, insufficient drying produces gas bubbles in extruded strand, melt-pressure fluctuation, and tensile strength losses of 10–20% after pelletizing. Once dried, pellets rehydrate rapidly: at 25 °C and 50% RH, surface moisture can return to process-significant levels within 15–30 min. Dried material must therefore be conveyed under dry air and held in hoppers purged to a dew point no higher than −30 °C. Long drying times above 4 h at 80 °C do not appreciably improve viscosity and may increase yellowness if oxygen is not excluded.

Melt-phase rheology is characterized by a shear-thinning power-law index between 0.4 and 0.6 across shear rates from 10 s⁻¹ to 1000 s⁻¹ at 200 °C. The apparent shear viscosity at 100 s⁻¹ for high-MW Ingeo PLA typically falls between 200 Pa·s and 600 Pa·s at 200 °C. Melt strength measured on a Rosand capillary rheometer with a haul-off attachment is commonly in the range of 0.05–0.15 N at 190 °C, compared with 0.02–0.06 N for low-viscosity injection PLA. These rheological differences explain why gate freeze time, nozzle pressure drop, and cooling time are longer than for low-viscosity grades. Injection molding with high-MW PLA requires back pressure of 0.5–1.5 MPa, screw rotation speed of 50–150 rpm, and a clamp force of 3–5 kN/cm² of projected area. Cooling time may need to be extended by 10–15% relative to standard PLA in thin-wall tools. The material should not be held above 220 °C for more than 5 min; residence time beyond this threshold produces measurable molecular weight loss by chain scission and lactide regeneration, even if visual degradation is not yet apparent.

Cold-runner molds with hardened S136 or P20 steel cavities are used. The high molecular weight increases melt viscosity at the gate, so gate diameters below 0.8 mm may cause jetting unless the injection velocity is reduced. Mold temperature uniformity should be held within ±2 °C across the cavity to avoid differential shrinkage and sink marks. PLA has a high affinity for polished steel; release difficulty appears when the mold temperature exceeds 40 °C because the part remains soft during ejection.

Thermo-Mechanical Performance Under Static Tensile and Flexural Loading

Unfilled high-molecular-weight Ingeo PLA exhibits tensile yield stress in the band of 55–65 MPa when tested to ISO 527-2:2012 on injection-molded type 1A specimens. Tensile modulus is commonly 3.2–3.6 GPa, flexural modulus 3.0–3.5 GPa under ISO 178:2019, and strain at break remains at 2–5%. Notched Izod impact values for unfilled high-MW PLA are generally 20–30 J/m under ASTM D256-23; the molecular weight increase provides only marginal toughening because the polymer remains brittle in the glassy state. The primary mechanical benefit is a reduction in flow-induced defects and better melt-state strength retention, not ductile failure. In applications involving repeated drop impact, hinge bending, or sub-zero service, an impact-modified PLA should be selected instead. Tensile bars conditioned at 23 °C and 50% RH for 48 h show tensile strength reductions of less than 5% compared with dry-as-molded values, but conditioning above 80% RH can produce larger losses through hydrolysis of the amorphous phase.

For systematic grade selection across the Ingeo PLA family, the following reference bands are generalized from publicly available technical literature. They are not lot-specific certificates for EcoVid 30GBIM and must be confirmed against the actual material specification.

When Heat Deflection and Crystallization Behaviour Govern Process Cycle Time

Amorphous PLA heat deflection temperature under 0.455 MPa load is typically 50–55 °C when tested to ISO 75-2:2013. The high-molecular-weight grade retains this thermal limitation unless crystallinity is deliberately induced by mold temperatures above 90 °C, by nucleating agents, or by post-mold annealing at 100 °C for 30 min. Differential scanning calorimetry at 10 °C/min shows a cold crystallization exotherm near 100–120 °C and a melting endotherm near 155–170 °C; annealed samples can reach 30–40% crystallinity. Isothermal crystallization half-times are strongly temperature-dependent: at 110 °C, a nucleated PLA can reach a half-time below 1 min, while at 90 °C the half-time often exceeds 5 min. Non-isothermal cooling above 20 °C/min suppresses crystallization almost entirely. Therefore, hot-mold cycle-time optimization requires a mold temperature of at least 100 °C and sufficient hold pressure to compensate for crystallization shrinkage. Mold shrinkage in the flow direction for amorphous parts is approximately 0.3–0.5%, while annealed semicrystalline parts can reach 1.0–1.5%. Processors should not combine 30GBIM with amine-based additives or polyamides with amine end groups; these catalyze chain scission in the melt and shift the melt flow rate outside the high-MW processing band.

Monofilament extrusion for fused filament fabrication uses a single-screw extruder with L/D 24:1–30:1, a water-bath quench at 20–40 °C, and laser micrometer control of diameter to ±0.03 mm. The high molecular weight provides the die swell and melt strength required for roundness retention at a draw ratio of 1.5:1 to 2.5:1, with the cooling bath placed 50–100 mm from the die. Exceeding these draw ratios produces ovality and surface stress whitening. On production lines, diameter variation is more often traced to inconsistent pellet feeding, wet resin, or insufficient melt-temperature uniformity than to molecular weight variation in the supplied lot. Batch-to-batch melt flow rate variation for commercial Ingeo PLA is typically less than ±1.0 g/10 min, but regrind content and drying history can shift viscosity more than intrinsic lot variation.

In masterbatch dilution, the shear-degraded boundary layers on the die land can generate black specks after a high-MW resin has been held at 210 °C for extended periods. To prevent this, the die should be purged with a lower-viscosity PLA at 200 °C before shutdown, and the screw should be run at low speed to pull the degraded layer from the barrel wall. The resin is incompatible with acidic or basic additives that accelerate ester hydrolysis; neutral masterbatches with mineral fillers may require a coupling agent to prevent viscosity reduction and plate-out on molding tools.

For food-contact applications, compliance must be confirmed for the complete formulation, including processing aids. In the European Union, unmodified Ingeo PLA grades are typically evaluated under EU 10/2011 for overall migration in simulant A (10% ethanol), simulant B (3% acetic acid), and simulant D2 (vegetable oil); the overall migration limit is 10 mg/dm². In the United States, food-contact use of polylactide is subject to the general provisions of 21 CFR 175.300 or an applicable Food Contact Notification, and the specific Ingeo grade should be listed by the supplier for the intended use. Compostability is not established by the polylactide backbone alone; finished articles require separate testing to EN 13432 or ASTM D6400. RoHS screening for cadmium, lead, mercury, and hexavalent chromium is performed by IEC 62321-5:2013; unmodified PLA is expected to yield results below detection limits. The resin should be stored in sealed foil-lined containers at 10–30 °C and below 50% RH. Opened containers should be consumed within 8 h unless connected to a dry-air purge. Avoid combination with amine-based additives and sustained hold times above 220 °C. The processing boundaries described here are drawn from the Ingeo PLA family; a formulation-specific technical data sheet from the supplier remains the authoritative source for lot-specific release limits.