Shanghai Jinfei HDPE 50100 is positioned as a high-density polyethylene resin for applications in which high melt strength, low melt flow, and long-term hydrostatic performance are controlling variables. The grade designation usually corresponds to a density class of 0.950 g/cm³ and a melt mass-flow rate class of 0.10 g/10 min when measured under ISO 1183-1:2019 and ISO 1133-1:2022. Publicly accessible technical bulletins describe the resin as a base material for PE100 pressure pipe compounds, thick-wall large-part blow molding, and high-molecular-weight sheet extrusion. Compared with standard blow-molding HDPE grades with melt flow rates in the 0.2–0.9 g/10 min range, HDPE 50100 moves the application window toward large-diameter pipe and parison-dominated processes rather than thin-wall injection. Published data for this specific Shanghai Jinfei configuration is limited; the ranges below are representative of the product class and are not a substitute for lot-specific certificates.

Shanghai Jinfei HDPE 50100: Specification Boundaries and Test Standard Anchors

Specification checks begin with melt flow rate and density because these two values define the flow class and the solid-state stiffness. HDPE 50100 is commonly reported with a melt mass-flow rate of 0.08–0.12 g/10 min at 190 °C under 2.16 kg per ISO 1133-1:2022. The density is typically 0.949–0.951 g/cm³ after conditioning at 23 °C per ISO 1183-1:2019. The low MFR value indicates high average molecular weight and is reflected in elevated tensile yield stress and flexural modulus. Tensile yield stress is reported between 22 MPa and 24 MPa on ISO 527-2:2012 specimens machined from compression-molded plaques. Elongation at break exceeds 600%, while flexural modulus is reported in the 880–920 MPa range under ISO 178:2019. Notched Charpy impact values under ISO 179-1:2023 are typically above 20 kJ/m² at 23 °C and above 10 kJ/m² at −30 °C. Hardness at 59–61 Shore D per ISO 868:2003 is consistent with an HDPE density near 0.950 g/cm³. Vicat softening temperature values of 121–124 °C under ISO 306:2022 method A50 are used as a thermal short-term indicator rather than a continuous service limit.

The additive package in commercial HDPE 50100 typically includes long-term thermal stabilizers and processing antioxidants sufficient for multiple extrusion passes, but the exact stabilizer composition is not publicly disclosed. For pipe applications, the resin is compounded with carbon black or color masterbatch to achieve the hydrostatic design bases described in ISO 4427-2:2019 for water and ISO 4437-2:2024 for gaseous fuels. Product compliance under REACH, RoHS, and FDA 21 CFR 177.1520 for polyolefin food-contact uses depends on the final compounded formulation and should be confirmed through the supplier’s regulatory statement, not inferred from the base resin designation alone.

Because the product is a high-density grade, crystallinity and slow crack growth resistance are more relevant in pressure environments than short-term tensile strength alone. Density is controlled by copolymer addition or by molecular architecture; small shifts from 0.949 g/cm³ to 0.951 g/cm³ alter flexural modulus and permeation resistance. In PE100 pipe compounds, the hydrostatic design basis is evaluated under ISO 9080:2012 using internal pressure tests at 20 °C, 40 °C, and 60 °C. The resin itself does not determine PE100 classification; the compound’s stabilizer package, carbon black dispersion, and pipe processing history all affect the regression curve. Batch-to-batch variance in melt flow rate should be monitored by ISO 1133-1:2022, and incoming resin lots should be checked for density by ISO 1183-1:2019 and for dispersion by ISO 18553:2018 in the finished compound.

When HDPE 50100 Replaces Higher-MFR Polyolefins in Extrusion Tooling

Replacing an HDPE grade with MFR in the 0.20–0.90 g/10 min range with HDPE 50100 changes screw torque, melt temperature, die pressure, and sag behavior. The lower MFR increases melt viscosity; in a grooved-feed single-screw extruder with L/D 30:1 and screw diameter 60 mm, the die inlet pressure for pipe operations can range from 250 bar to 350 bar, depending on die resistance and throughput. The same tooling used for an 0.30 g/10 min blow-molding grade may require the barrel temperature set points to be raised by 5–10 °C in the rear zones to avoid excessive torque, while the melt temperature measured at the adapter should remain at 200–220 °C. Equipment with a general-purpose screw and no grooved feed section may show lower output stability because high-molecular-weight polyethylene pellets can slip against a smooth barrel wall. The benefit is reduced parison sag and better wall-thickness uniformity in large-diameter pipe and large-part blow molding. In spiral mandrel dies, the grade is used between 110 mm and 630 mm diameter for thick-wall pressure pipe, subject to die head pressure limits and screen-pack condition. Published data for this specific configuration is limited, so commissioning trials should record pressure, torque, and melt quality against ISO 1133-1:2022 check samples rather than relying on general HDPE setup tables.

The comparative ranges are generalized from polyolefin processing references and not from a single Shanghai Jinfei datasheet; they are included to define the substitution logic rather than to establish lot-specific limits.

Differences from general-purpose HDPE 5502 and HDPE 5000S appear in both flow and mechanical performance. Commercially available HDPE 5502, with a typical MFR near 0.20 g/10 min, is easier to process but produces lower melt strength than HDPE 50100. HDPE 5000S, with a typical MFR near 0.90 g/10 min, is used where faster injection flow and shorter cycle times dominate. The low MFR of 50100 reduces spiral flow length in injection molding; flow-length tables for polyolefins indicate that an MFR 0.10 g/10 min material may fill 20–40% shorter paths than an 0.30 g/10 min resin at the same pressure, although mold geometry and gate design override this generalization. The higher molecular weight that restricts flow improves slow crack growth resistance and long-term hydrostatic strength, which is why PE100 pressure-pipe compounds use low-MFR base resins in the 0.05–0.15 g/10 min range under ISO 12162:2009. Therefore, the decision to replace a higher-MFR HDPE with 50100 is supported when pipe hoop stress, sag resistance, or environmental stress cracking resistance is the limiting design criterion, and not when thin-wall fill speed or cycle time drives the process.

Large-part blow molding of industrial drums, automotive fuel tanks, and intermediate bulk containers uses low-MFR HDPE for parison stability. With MFR below 0.15 g/10 min, HDPE 50100 allows longer parisons with less elongation under gravitational load. Die swell is higher than for 0.30 g/10 min blow-molding grades, so tooling must be modified: the die gap is widened by 10–15% relative to conventional grades to maintain target wall thickness. The extrusion head is typically operated with a melt temperature of 190–210 °C and mold temperature of 10–20 °C; blow pressure is kept between 6 bar and 8 bar. If the accumulator head is not designed for high-molecular-weight resin, melt fracture or shark-skin may appear on the parison surface at moderate output rates. Trials with different die land lengths and spiral groove angles are required because published data for this specific configuration is limited.

What Processing Limits Emerge with Low-MFR Pipe-Grade Resin?

Low-MFR HDPE grades impose tighter thermal and moisture controls than injection-molding grades. HDPE is hydrophobic, but surface condensation on pellets stored in unheated silos or exposed to high humidity can introduce moisture above 0.05 wt%. Desiccant drying at 80 °C for 2–4 h with a dew point below −30 °C is recommended when ambient relative humidity exceeds 60% or when the regrind fraction exceeds 20%. Melt temperature should not exceed 230 °C; prolonged residence time at higher temperatures promotes thermal oxidative degradation, visible as yellowing, gel formation, or viscosity shifts. Extruders with L/D 30:1–36:1, barrier screws, and gentle mixing sections are preferred because they achieve melt homogeneity without excessive shear heating. The material is incompatible with pro-oxidant additives designed for degradable polyethylene films and should not be blended with recycled polypropylene above 2–3 wt%, since phase separation can reduce weld integrity in pressure pipe. Additive concentrates containing amine-based flame retardants may interfere with the long-term antioxidant package; such combinations require pre-qualification testing under ISO 9080:2012 hydrostatic design methods before production use.

The effective melt-temperature processing window for HDPE 50100 is narrow in high-shear pipe dies: excursions below 190 °C create unmelts and pressure fluctuations, while excursions above 230 °C increase the risk of oxidation. In a 60 mm grooved-feed extruder, the temperature difference between the rear barrel zone and the die can exceed 20 °C; the rear zone may be set to 180 °C to stabilize solids conveying, while the die is held at 210 °C. If the melt temperature drops by more than 5 °C from the target at the adapter, thicker walls may show internal melt lines under ISO 18553:2018 dispersion inspection. This is a critical threshold because low-MFR HDPE does not recover homogeneity as easily as higher-MFR grades.

HDPE 50100 pellets should be stored in a dry, enclosed silo or hopper at ambient temperature below 40 °C. If outdoor silos are used, condensation must be avoided through desiccant dryers or hopper dryers. Pellets with surface moisture above 0.05 wt% can produce surface splay and internal voids in pipe walls. Because the resin is supplied in pellet form with a bulk density near 540–580 kg/m³, pneumatic conveying systems should be sized for dense-phase or dilute-phase transfer with air velocity high enough to prevent saltation but low enough to avoid angel hair formation. Angel hair can block feed throats and cause melt flow variations. Conveying line speeds above 20 m/s may generate fines that later appear as gels; therefore, filters and fines removal equipment are used before extrusion. Published data for this specific configuration is limited, but these handling limits are standard for high-molecular-weight HDPE.

In PE100 water distribution pipe, the compounded HDPE 50100 resin is extruded through a spiral mandrel die with a temperature profile of 180 °C at the feed throat rising to 210 °C at the die head. Melt temperature at the adapter is held at 200–220 °C; melt pressure before the screen pack is typically 250–350 bar for 200 mm diameter SDR 11 pipe at commercial output rates. Vacuum calibration tanks and spray-cooling water at 15–20 °C are used to fix dimension. The finished pipe is tested for hydrostatic strength under ISO 4427-2:2019 and ISO 9080:2012; a PE100 designation requires that the compound reaches a minimum required strength of 10 MPa after 50 years at 20 °C. Large-part blow molding of the same base resin uses lower screw speeds and adjusted die gaps because the high melt strength increases die swell. Parison melt temperature is maintained in the 190–210 °C range; mold temperatures of 10–20 °C are common for cooling. In both processes, the low MFR is an asset only when tooling, screw geometry, and process controls are matched to the high viscosity. Published data for this specific Shanghai Jinfei configuration is limited; plant trials and lot-specific certificates must be used to set exact limits.