Polylactic Acid REVODE713

In thin-wall cutlery injection moulding, REVODE713 is treated as a high-melt-flow PLA resin whose process stability depends more on residual moisture than on barrel temperature. The pellets are predried in a desiccant hopper at a dew point not above −40 °C, at 80 °C for 4 h to 6 h, until the residue measured by ISO 15512:2019 is below 0.025% (250 ppm). Barrel temperature is profiled from 165 °C at the throat to 195 °C at the metering zone, with the nozzle kept below 205 °C to limit lactide outgassing and screw drool. Mould cooling temperature is held between 15 °C and 35 °C for amorphous, transparent cutlery; elevated mould temperatures above 90 °C are used only where crystallized spoons require dimensional stability at higher ambient temperatures. Injection speed is set to fill the cavity in 0.8 s to 1.5 s, hold pressure is maintained at 50 MPa to 70 MPa for gate seal, and back pressure of 5 MPa to 8 MPa with screw speed of 70 min⁻¹ to 120 min⁻¹ prevents melt-temperature overshoot. Gate thickness is not less than 0.6 mm and land length is not above 1.2 mm, because PLA freezes rapidly and thin gates cause short shots, jetting, and weld-line splitting. Under ISO 527-2, the oriented mouldings typically show tensile modulus between 3300 MPa and 3600 MPa and elongation at break below 4%; under ISO 179-1/1eA, notched Charpy values in unlaminated cutlery are usually 2.5 kJ/m² to 4 kJ/m². End products are disposable forks, spoons, stirrers, and sampling spatulas that meet EN 13432:2000 or ASTM D6400-19 when the entire packaging article is certified, not only the resin pellet. Continuous service temperature is governed by ISO 75-2/B at 0.45 MPa, which remains near 55 °C in amorphous parts; the cutlery is therefore not positioned for hot soup, microwave reheating, or extended contact with boiling water. Published data for this specific grade in thin-wall cutlery configuration is limited; the parameter ranges cited are derived from ISO methods and general PLA injection-moulding practice.

What Restricts Hot-Fill Capability in Thermoformed PLA Portion Cups?

The restriction is determined by the low amorphous heat deflection point, not by melt strength alone. Sheet extrusion of REVODE713 is run at melt temperatures between 180 °C and 205 °C, with a polished roll stack at 40 °C to 50 °C; sheet thickness is controlled from 0.3 mm to 0.8 mm and residual moisture is kept below 0.02%. Thermoforming uses a plug-assisted process with an areal draw ratio of 2:1 to 3:1, sheet surface temperature of 85 °C to 110 °C before the mould closes, and aluminium or steel tooling held at 95 °C to 110 °C to induce 25% to 35% crystallinity in the finished wall. The additional crystallization raises the Vicat softening point measured under ISO 306/B50 from approximately 55 °C in amorphous sheet to a practical ceiling near 95 °C, but the thermoformed cup still fails hot-fill above 50 °C because wall stock thins at corner radii during plug inversion. Process operators compensate with plug speed 250 mm/s to 400 mm/s and plug temperature near 100 °C; however, the crystallization window narrows between 95 °C and 120 °C per ISO 11357-3, making cycle time the control variable rather than oven setpoint. End formats include 150 ml to 500 ml dessert cups and dairy portion packs. Compliance follows Commission Regulation (EU) No 10/2011, including Annex II overall migration limit not exceeding 10 mg/dm² for food-contact verification, and EN 13432:2000 where compostability is claimed; the cups are intended for chilled or ambient dry use, not for retort, microwave, or hot-fill above 50 °C.

Before REVODE713 pellets are converted into fused filament fabrication feedstock, the material is predried at 60 °C for 4 h to 6 h to a maximum moisture content of 250 ppm. The extrusion line uses a single-screw extruder with 28:1 L/D and a three-zone screw with shallow metering depth, operated at a melt temperature of 185 °C to 205 °C and a melt pump pressure of 8 MPa to 12 MPa before the die. Filament is quenched in a water bath maintained at 45 °C to 55 °C; bath temperature below 40 °C creates an amorphous skin with internal voids, while bath temperature above 60 °C increases crystallization and makes the filament too brittle for spooling. A dual-axis laser gauge controls diameter to 1.75 mm ± 0.05 mm, with ovality not exceeding 0.02 mm; feedback adjusts puller speed between 20 m/min and 50 m/min. The printed parts are built at a nozzle setpoint of 200 °C to 220 °C and a bed temperature of 20 °C to 50 °C; print speed is kept between 40 mm/s and 80 mm/s to avoid under-extrusion from melt viscosity shifts. ISO 527-2 values for printed PLA tensile bars typically fall between 45 MPa and 55 MPa in the XY direction, which is lower than injection-moulded reference values because interlayer fusion limits load transfer. End uses are prototype jigs, assembly aids, and dry-goods display fixtures; parts are not suitable for continuous exposure above 50 °C or to water spray above 40 °C.

Extrusion Coating Paperboard with a PLA Melt Curtain at 20–30 g/m²

Paperboard coating with REVODE713 requires a wider die gap and a shorter air gap than LDPE because PLA's extensional viscosity is lower and film neck-in is severe at melt temperatures above 230 °C. The resin is predried to below 0.015% moisture and fed to a 90 mm screw with 30:1 L/D; melt temperature at the die is controlled between 200 °C and 225 °C. The flat die gap is set at 0.4 mm to 0.7 mm, and the air gap from die lips to nip is held at 180 mm to 250 mm to minimize neck-in before the melt curtain contacts the paperboard. Corona treatment at 2 kW to 4 kW is applied to the board surface immediately before the nip; coating weight is maintained at 15 g/m² to 30 g/m² and controlled by line speed of 80 m/min to 200 m/min with a cooled polishing roll at 25 °C to 40 °C. Adhesion is tested by ISO 2409 cross-cut tape pull; values below grade 1 are typical on corona-treated kraft, while untreated board shows delamination. End structures include cold-drink paper cups, sandwich boxes, and dry-catering trays. Regulatory compliance for food-contact paperboard is assessed under Commission Regulation (EU) No 10/2011 and, where applicable, FDA 21 CFR 176.170 for paper and paperboard components; PLA itself requires verification against the supplier's FCN because 21 CFR 177.1520 does not apply to PLA. The coating is not a high-barrier layer; oxygen transmission under ISO 15105-2 and water-vapour transmission under ISO 15106-3 are higher than PE and PET, so this track is for short-life food service, not long shelf-life packaging.

When GPPS Is Replaced by REVODE713 in Transparent Dry-Goods Blisters

GPPS substitution is viable only when the tool is modified to accept PLA's lower thermal conductivity and wider viscosity dependence on shear. The mould shrinkage under ISO 294-4 is typically 0.3% to 0.8% parallel to flow and 0.2% to 0.5% transverse, compared with GPPS at 0.3% to 0.6%; tools dimensioned for GPPS may still pass dimensional checks if the shrinkage correction is adjusted, but side-wall rib thickness below 0.4 mm creates short shots. Melt temperature is kept between 175 °C and 195 °C, mould temperature at 15 °C to 30 °C, injection velocity to fill in 0.5 s to 1.0 s, and hold pressure from 45 MPa to 65 MPa. A 180-tonne clamp press running a single-cavity electronic accessory blister with projected area of 350 cm² requires a clamping force reserve because PLA's viscosity curve under ISO 11443 falls sharply above 210 °C; any overshoot causes flash and screw drool. The end product is a clear, brittle blister for dry goods, electronics installation parts, or stationery. Drop impact is limited: notched Charpy under ISO 179-1/1eA remains near 2 kJ/m² to 4 kJ/m², so the blister must not be used for heavy tools or sharp metal components without radiused corners. Compliance includes REACH polymer exemption confirmation, RoHS heavy-metal screening, and EN 13432:2000 if the blister is claimed compostable.

For refrigerated dessert packaging lines, cold-chain moulded tubs produced from REVODE713 are engineered for close dimensional control in lid rims rather than impact toughness, because PLA exhibits brittle fracture below 10 °C unless impact-modified. The melt is processed at 180 °C to 200 °C with mould temperature at 15 °C to 35 °C; thin side walls of 0.6 mm to 1.0 mm require fast injection with valve-gated hot runners and gate diameter not below 0.8 mm. Under ISO 527-2, tensile modulus is 3200 MPa to 3600 MPa and stress at break is 55 MPa to 65 MPa; under ISO 178, flexural modulus is approximately 3000 MPa to 3500 MPa. The lid rim seats are held to a circularity tolerance of 0.2 mm using an eight-cavity cold-runner tool, because post-mould moisture uptake above 0.3% causes dimensional swelling. Secondary operations include ultrasonic welding of tamper-evident bands on lids, which requires horn amplitude of 30 µm to 50 µm and weld pressure of 0.2 MPa to 0.4 MPa; PLA welds best with short 0.1 s to 0.3 s pulses to avoid melt squeeze-out. The finished tubs are used for chilled dairy, frozen desserts at −20 °C only when impact modifiers are added, and cold packed dry goods. Compliance is under Commission Regulation (EU) No 10/2011; compostability claims require EN 13432:2000. These tubs are not for microwave or oven use.