VeryGreen™ VG7262 High Impact General Purpose Polylactic Acid is a melt-processable compound based on semi-crystalline poly(L-lactic acid) modified with an elastomeric impact-modifier package and a processing stabilizer system. The grade is supplied as cylindrical pellets with a nominal bulk density of 0.72 g/cm³ to 0.78 g/cm³ when measured in accordance with ISO 60:1977. It is designed for injection moulding, sheet extrusion, and profile extrusion applications in which unmodified PLA fracture behavior is inadequate but full engineering-polymer cost or fossil-carbon content is not justified. Melt flow rate measured at 190 °C with a 2.16 kg load is typically 4 g/10 min to 8 g/10 min under ISO 1133-1:2022. The defining mechanical feature is a notched Izod impact energy above 25 kJ/m² under ISO 180/A while tensile modulus remains above 2,200 MPa under ISO 527-2:2012. This balance is obtained through a dispersed elastomer phase that increases crack-initiation energy without fully eliminating the shear-yield stress of the PLA matrix.

Prior to melt processing, the resin must be dried in a closed-loop desiccant dryer to a residual moisture content below 250 ppm. Drying at 80 °C for 4 h with a dew-point setpoint of −40 °C is the standard starting condition. If ambient relative humidity exceeds 60 %, open-hopper residence time should not exceed 30 min without an active dry-air purge. Regrind from sprues and runners may be reintroduced at up to 20 wt% provided the regrind is re-dried and free of dust and oil contamination. Higher regrind fractions reduce melt stability and increase the probability of surface splay caused by hydrolytic chain scission.

What Process Parameters Control Melt Stability in High-Impact PLA?

Injection moulding and sheet extrusion lines equipped with 20:1 to 30:1 L/D general-purpose screws should maintain a melt temperature of 180 °C to 200 °C. The upper processing boundary is 210 °C; above this threshold, ester-link degradation accelerates and the dispersed impact-modifier phase can coalesce, producing a measurable loss in notched impact strength. Barrel zone settings from rear to nozzle are typically 160 °C, 175 °C, 185 °C, 190 °C, and 195 °C, but air-shot pyrometry should be used because shear heating in small shot volumes can raise actual melt temperature by 5 °C to 10 °C. Screw back pressure should be controlled at 0.3 MPa to 0.7 MPa; higher back pressure increases residence-time heat history without improving dispersion. Mold temperature should be held between 15 °C and 40 °C. Excessive mold temperature reduces cycle time but also lowers the effective quench rate, allowing secondary crystallization that increases modulus while reducing impact fracture energy. Published data for this specific configuration on high-shear twin-screw dispersive mixing is limited, and start-up trials should therefore use a wider melt-temperature guard band until stabilizer consumption is confirmed by melt-flow retention after 5 min residence.

Applications for VG7262 cluster in indoor housings, clips, brackets, small appliance components, consumer electronics enclosures, point-of-sale fixtures, and non-carbonated closure systems. The grade has lower modulus than unmodified PLA but resists brittle hinge failure, snap-fit breakage, and drop-induced corner fracture better than standard extrusion-grade PLA. Components moulded at the lower end of the melt-temperature range often show higher impact retention because the elastomer domains remain smaller and more regularly distributed. Shrinkage is anisotropic and typically 0.3 % to 0.5 % in the flow direction and 0.4 % to 0.6 % transverse to flow when measured on 60 mm × 60 mm × 2 mm plaques under ISO 294-4:2018. Dimensional stability should not be assumed identical to amorphous PLA; post-mould conditioning at 23 °C and 50 % relative humidity for 24 h is required before critical dimension verification.

When VG7262 Replaces General-Purpose ABS in Indoor Housings

When VG7262 is substituted for general-purpose ABS, the comparison is not a simple impact-versus-heat trade. The PLA compound offers lower melt density, higher renewable carbon content by weight, and reduced dependence on styrene monomer supply, but it carries a lower continuous-use temperature envelope and higher moisture sensitivity before processing. The table below outlines the comparative values that govern substitution decisions.

Compared with standard PLA, VG7262 trades tensile modulus for a fivefold to eightfold increase in notched Izod impact energy. That shift is material in living-hinge components, threaded bosses, and snap arms where standard PLA fails by brittle crack propagation before yield. Compared with general-purpose ABS, VG7262 exhibits lower heat deflection under load and greater sensitivity to hydrolytic degradation during open-loop drying. It should not be selected for automotive interior components exposed to upper dashboard temperatures above 85 °C, nor for hot-water contact parts, unless the application-specific thermal load is verified under ISO 75-2:2013 and the actual wall temperature of the installed part is measured.

Drying, Mold Temperature, and Screw Back Pressure Settings

Regulatory documentation for the compound should be requested from the supplier for the specific lot because impact-modifier composition can affect food-contact suitability under FDA 21 CFR 177.1520 and European Commission Regulation (EU) No 10/2011. Industrial compostability of the PLA matrix should be evaluated by ISO 14855-1:2012 on the finished article; the presence of non-PLA modifiers may reduce the rate of disintegration in some composting environments. The grade is not formulated for outdoor UV resistance, and long-term weathering must be evaluated under ISO 4892-2:2013 if exposure exceeds incidental indoor light. Avoid blending with amine-based processing aids or nitrogen-rich purge compounds; residual alkalinity accelerates ester hydrolysis at melt temperature. Purging should be conducted with a low-MFR PLA purge compound, never with PVC or acetal residues, because incompatible melt phases can delaminate in the nozzle and hot-runner manifold. For hot-runner systems, manifold and nozzle temperatures should not exceed 200 °C, and residence time in the manifold should be limited to 3 min to 4 min at temperature. Production-scale audits on 80- to 120-tonne electric injection moulding machines with 22:1 L/D to 25:1 L/D general-purpose screws indicate that melt-temperature consistency within ±3 °C is required to hold notched Izod values above 28 kJ/m². Larger shot volumes or hot-runner offset should be compensated by reducing the rear zone by 5 °C rather than raising nozzle temperature.

No claim is made for continuous load-bearing use above 60 °C. Creep, stress relaxation, and fatigue performance must be generated for the specific part geometry and load history because published data for this specific configuration is limited. The material should be stored sealed in moisture-barrier packaging below 30 °C and away from direct sunlight. Once opened, unused pellets should be re-dried before moulding if exposure exceeds 8 h at 50 % relative humidity.