| HS Code | 215911 |
| Productname | Beijing Evergrow Resources UHMWPE ER-25 |
| Polymertype | Ultra-high molecular weight polyethylene |
| Form | White powder |
| Molecularweight | 2.5 × 10^6 g/mol |
| Density | 0.930–0.935 g/cm³ |
| Bulkdensity | 0.40–0.50 g/cm³ |
| Particlesize | 100–300 µm |
| Meltingpoint | 130–136 °C |
| Crystallinity | 45–55% |
| Tensilestrengthatyield | 17–20 MPa |
| Elongationatbreak | 300–450% |
| Notchedcharpyimpactstrength | ≥100 kJ/m² |
| Shoredhardness | 60–65 |
| Waterabsorption | <0.01% |
| Coefficientoffriction | 0.10–0.22 |
| Thermalconductivity | 0.41–0.51 W/(m·K) |
| Dielectricconstant | 2.3 at 1 MHz |
| Volumeresistivity | >10^15 Ω·cm |
| Color | White |
As an accredited Beijing Evergrow Resources UHMWPE ER-25 factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Beijing Evergrow Resources UHMWPE ER-25 is packed in 25 kg multiwall paper bags, palletized and shrink-wrapped for secure shipment. |
| Container Loading (20′ FCL) | 20′ FCL loading: UHMWPE ER-25 in 25 kg bags, palletized, shrink-wrapped, typically 12.5–16 MT net, securely stowed for ocean export. |
| Shipping | Beijing Evergrow Resources UHMWPE ER-25 ships as a non-hazardous, non-regulated polymer. Use sealed bags or drums, keep cool, dry, and clean, away from moisture, sunlight, ignition sources, and contamination. No UN number, hazard class, or packing group applies. Follow local transport rules and preserve documentation. |
| Storage | Store Beijing Evergrow Resources UHMWPE ER-25 in a cool, dry, well-ventilated warehouse, away from direct sunlight, heat, flames, and strong oxidizing agents. Keep original containers sealed and clearly labeled, protecting the material from moisture, dust, and contamination. Stack pallets securely to prevent deformation or rupture. Maintain good housekeeping and follow local regulations and supplier safety data sheet. |
| Shelf Life | Beijing Evergrow Resources UHMWPE ER-25: typically two years if stored unopened, cool, dry, well-ventilated, away from direct sunlight and heat. |
In wet-process lithium-ion separator manufacturing, Beijing Evergrow Resources UHMWPE ER-25 is incorporated into a paraffin oil dispersion before thermally induced phase separation. Formulation ratio on production lines is held between 15 wt% and 30 wt% ER-25 in paraffin oil, with 0.5 wt% to 3.0 wt% fumed silica added when the separator must retain electrolyte under low-pressure charge conditions; no other polymer matrix is used. Compliance for separator rolls entering lithium-ion cell assembly is assessed under cell-level standards IEC 62660-3:2022, UL 1642, and GB/T 36363-2018, while manufacturing quality systems are typically audited to IATF 16949:2016 and ISO 9001:2015. The downstream production process uses a co-rotating twin-screw compounder with specific energy input of 0.18 kWh/kg to 0.35 kWh/kg and barrel temperatures from 180 °C to 230 °C, followed by sheet die extrusion onto a chill roll at 15 °C to 35 °C, extraction of paraffin oil with methylene chloride or n-hexane, and biaxial stretching at 80 °C to 130 °C. Terminal product types include 5 µm to 25 µm microporous separator films for cylindrical, prismatic, and pouch cells, with porosity of 38% to 52% and Gurley values from 150 s/100 mL to 400 s/100 mL. The critical process boundary is quenching rate: gel film cooled below 0 °C at high line speed develops coarse spherulites that lower puncture strength measured under ASTM F1306. Residual paraffin oil must be driven below 0.5 wt% because retained oil migrates to the electrode interface and raises interfacial resistance after cell formation.
Because gel spinning imposes elongational stress on semi-dilute polymer solutions, ER-25 powder is dissolved in decalin or paraffin oil at a polymer concentration of 5 wt% to 10 wt%; when spinneret hole diameter is below 1.0 mm, the concentration is further reduced to 8 wt% or less to suppress die swell and draw resonance. Compliance for marine rope yarns references ISO 18692:2007 and ISO 9554:2019, while ballistic composite intermediates are tested under NIJ 0101.07 level requirements and cut-resistant glove liners are classified under EN 388:2016+A1:2018. The downstream production process uses a twin-screw dissolver at 140 °C to 160 °C, melt metering to multi-hole spinnerets at 150 °C to 180 °C, air quench, solvent extraction, and multi-stage hot drawing at total draw ratios of 40:1 to 80:1. Terminal product types include 110 dtex to 880 dtex multifilament yarns, unidirectional ballistic prepregs, offshore mooring ropes, fishing braids, and cut-resistant sleeves. The operational boundary is the final draw window: at draw ratios above 80:1, filament break frequency increases unless gel temperature is maintained within ±2 °C at the draw plate. Unlike melt-spun materials, the transition from extensional thickening to filament rupture is rapid, so spin-line tension must be monitored continuously. Published data for ER-25-specific spin-line tension and draw resonance at full production scale is limited; pilot trials are required to map extruder output against draw roll speed before specifying machine parameters.
Mechanically, ram extrusion of ER-25 into solid profiles is a pressure-driven process that exploits the powder's high zero-shear viscosity; the material is charged into the barrel as virgin powder rather than melt-compounded. Formulation ratio for industrial wear profiles is 100 wt% ER-25 unless static dissipation is specified, in which case carbon black is metered at 0.5 wt% to 2.0 wt%; silicone-based external lubricant is added at 0.2 wt% to 0.5 wt% only when die land surface defects appear. Applicable compliance includes FDA 21 CFR 177.1520 for incidental food contact, EU 10/2011 for repeated-contact plastic materials, and REACH Annex XVII for goods sold into the EU; mechanical property data are generated under ISO 11542-1, ISO 527-2:2012, and ASTM D4020. The production process operates at ram pressures of 20 MPa to 40 MPa, barrel temperatures from 190 °C to 230 °C, die land length-to-diameter ratios of 8:1 to 16:1, and cooling zone temperatures from 40 °C to 80 °C; ram stroke on production machines is typically 300 mm to 600 mm. Terminal products include chain guide rails, conveyor wear strips, chute liners, star wheels, and packaging machine guides. The process incompatibility is the addition of inorganic fillers above 5 wt%, which generates pressure spikes at the die entry and produces internal voids that are detectable only after ultrasonic inspection or density gradient column testing.
Sintered porous media production from ER-25 powder is controlled by sieved particle size distribution, mold pack density, and sintering time rather than by screw melt processing. Formulation ratio is neat powder in the 200 µm to 500 µm sieve fraction when finished pore diameters from 10 µm to 80 µm are specified; no binder is added, and the powder is dried for 2 h at 80 °C when ambient relative humidity exceeds 60%. Compliance for compressed-air filter elements references ISO 8573-1:2010 particle classes and ISO 12500-1:2007 for coalescing filter performance; pore-size characterization follows ASTM F316-03 bubble-point method, and food-contact air sparging components must meet FDA 21 CFR 177.1520 and EU 10/2011. The downstream production process involves vibration-assisted mold filling, compression at 4 MPa to 10 MPa, and sintering in a convection oven at 160 °C to 200 °C with soak times of 25 min to 40 min per 10 mm of wall thickness. Terminal product types include porous filter tubes, air silencer elements, pneumatic mufflers, battery vent plugs, and sparging discs for chemical vessels. The sintering plateau is the critical control point: mold temperature above 205 °C collapses interconnected porosity because particle coalescence accelerates, while soak times below 20 min reduce sinter neck strength measured by compressive crush load under ISO 844:2014 below the minimum required for filter cartridge handling without fracture.
In orthopedic bearing conversion, ER-25 requires a validated consolidation route because implant-grade stock is machined from compression-molded or ram-extruded forms that must satisfy ISO 5834-2:2019, ASTM F648-23, and ISO 10993-1:2018 biological evaluation requirements. Formulation ratio is 100 wt% virgin ER-25; when vitamin E stabilization is specified, alpha-tocopherol is blended at 0.05 wt% to 0.10 wt% before consolidation and homogenised at 60 °C for 30 min to avoid oxidative index heterogeneity across the molded block. The downstream production process is compression molding at 20 MPa to 30 MPa and 200 °C to 220 °C, followed by controlled cooling at 5 °C/min to 10 °C/min; bearing preforms may be machined and then crosslinked by electron-beam or gamma irradiation at 25 kGy to 100 kGy, with remelting or annealing performed to eliminate residual free radicals. Terminal product types include acetabular liners, tibial inserts, patellar components, glenoid bearings, and intervertebral disc cores. The limitation for ER-25 in this application is that reactor-grade powder certification alone does not establish implant-grade compliance; the converter must verify density, ash content, stabilizer content, and consolidated properties on each lot under ASTM F648-23 test protocols, because cross-lot variation in particle shape can alter oxidation resistance after irradiation. Published data for ER-25-specific clinical bearing performance is limited; validation testing is required before regulatory submission.
Lead-acid battery separator lines compound ER-25 with precipitated silica and process oil to generate a microporous sheet in which silica creates electrolyte wettability and UHMWPE supplies puncture resistance. Formulation ratios on production lines commonly span 20 wt% to 30 wt% ER-25, 55 wt% to 65 wt% precipitated silica, 10 wt% to 15 wt% naphthenic process oil, and 0.5 wt% to 1.5 wt% carbon black for oxidation resistance. Compliance references IEC 61056-1:2012 for general-purpose lead-acid battery separators, EN 50342 for automotive battery packs, and ISO 9001:2015 for manufacturing quality; separators for stationary cells are also evaluated under IEEE 484 or the relevant telecommunication backup battery specification. The downstream production process uses a co-rotating twin-screw compounder at 160 °C to 200 °C, a sheet die with lip gap from 0.4 mm to 1.0 mm, hexane extraction of process oil, and calendering to set final backweb thickness. Terminal product types include separator rolls of 0.25 mm to 1.5 mm backweb thickness for SLI, deep-cycle, motive power, and stationary lead-acid batteries. The process boundary is oil extraction rate: residual oil above 0.5 wt% reduces electrolyte backweb saturation and increases electrical resistance measured under IEC 61056-1:2012, while over-extraction embrittles the sheet and lowers puncture resistance under ASTM D4830.
Competitive Beijing Evergrow Resources UHMWPE ER-25 prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8618136850665 or mail to admin@ascent-chem.com.
We will respond to you as soon as possible.
Tel: +8618136850665
Email: admin@ascent-chem.com
Flexible payment, competitive price, premium service - Inquire now!
Beijing Evergrow Resources supplies UHMWPE ER-25 as a virgin, unfilled ultra-high-molecular-weight polyethylene powder intended for ram extrusion, compression molding, and direct sintering of stock shapes and semi-finished components. The grade belongs to the ISO 11542-2 class of polyethylene that exhibits no measurable melt flow rate under ASTM D1238/ISO 1133-1 at 190 °C and 21.6 kg, and is characterized by viscosity-average molecular weight in excess of 1.5 × 10⁶ g/mol. The powder is supplied as a white, free-flowing solid with particle size distribution controlled to suit continuous compaction; typical bulk density ranges from 0.40 to 0.50 g/cm³, although shipment-specific values appear on the certificate of analysis. ER-25 is not a melt-processable resin in conventional single-screw extrusion; it is processed by pressure-assisted sintering in which compacted powder particles are consolidated under heat. The molecular architecture removes the need for external lubricants in many wear applications because the polymer itself provides a low dry sliding coefficient against polished steel, commonly in the range of 0.10 to 0.22 under laboratory ASTM G99 pin-on-disc conditions.
Under the manufacturer’s certificate of analysis, ER-25 is qualified against the following property set. Density determined in accordance with ISO 1183-1 typically falls between 0.930 and 0.940 g/cm³. Tensile yield stress measured at 50 mm/min according to ISO 527-3 is usually not less than 20 MPa, while elongation at break typically exceeds 300 %. Shore D hardness per ISO 868 is generally 60 to 70. Notched Charpy impact strength per ISO 179-1/1eA is reported as no break at 23 °C, although the exact value depends on test specimen preparation. The material absorbs less than 0.01 % water after 24 h immersion under ISO 62. Vicat softening temperature per ISO 306/A50 is normally 79 °C to 84 °C. Because no melt flow is measurable, molecular characterization is performed by dilute solution viscometry in decalin at 135 °C per ISO 1628-3; the intrinsic viscosity for virgin UHMWPE of this type is commonly above 20 dL/g. Differential scanning calorimetry under ISO 11357-3 shows a melting endotherm between 130 °C and 136 °C and crystallinity between 45 % and 55 %. These values represent the unfilled UHMWPE class, and final acceptance limits should be verified against the supplier’s product specification for individual batches.
| Property | Test method | Typical envelope |
| Density | ISO 1183-1 | 0.930–0.940 g/cm³ |
| Tensile yield stress | ISO 527-3 | ≥ 20 MPa |
| Elongation at break | ISO 527-3 | ≥ 300 % |
| Shore D hardness | ISO 868 | 60–70 |
| Water absorption | ISO 62 | < 0.01 % |
| Vicat softening temperature | ISO 306/A50 | 79–84 °C |
| Intrinsic viscosity | ISO 1628-3 | > 20 dL/g |
Because ISO 11542-2 identifies UHMWPE by melt flow rate below 0.01 g/10 min and molecular weight above 1.5 × 10⁶ g/mol, ER-25 cannot be characterized by routine melt flow index measurements. Bulk density and particle size distribution are also controlled because they determine feeding consistency on ram extrusion lines; batch certificates commonly report bulk density, sieve retention, and moisture content. Conversion between intrinsic viscosity and viscosity-average molecular weight uses the Mark-Houwink equation with constants for linear polyethylene in decalin at 135 °C; however, the supplier’s certificate of analysis usually reports intrinsic viscosity rather than absolute molecular weight to avoid interlaboratory differences in solution preparation.
On production-scale ram extrusion lines, ER-25 powder is gravity-fed into a heated barrel where a reciprocating ram compacts successive charges against a forming die. The consolidated powder is maintained under axial pressure while the temperature in the barrel is raised sufficiently to sinter the particle interfaces. Die temperature control within ±2 °C is required in the heating zone adjacent to the die exit; local excursions above 230 °C accelerate thermo-oxidative chain scission and generate oxidized surface defects, while insufficient heating below 180 °C produces incomplete consolidation and visible cold-laminar boundaries. Typical hydraulic forming pressures for unfilled UHMWPE range from 10 to 30 MPa, and ram speeds are held between 5 and 30 mm/min depending on cross-sectional thickness. Thin sections below 10 mm require faster heat transfer but shorter dwell, whereas sections above 50 mm demand extended sintering times and staged cooling to prevent core porosity. Pre-drying is not normally required for the powder if stored below 60 % relative humidity, but material exposed to high ambient moisture should be dried at 80 °C for 4 h before processing to avoid steam-induced microvoids.
Compression molding of ER-25 sheet and rod uses press platens heated to 200 °C with applied pressure between 10 and 20 MPa. Sintering time is typically 10 to 15 min/cm of thickness, and cooling under pressure at rates below 2 °C/min is critical to minimize warpage. Batch-to-batch variance in powder bulk density shifts compaction ratio; operators monitor charge weight rather than volume to maintain consistent part density. The most frequently observed failure mode on high-output ram extrusion lines is die lip fouling from oxidized fines generated by excessive residence time at the barrel wall; periodic purging with virgin powder and reducing top-zone temperature by 5 °C addresses the defect. ER-25 is not suitable for conventional single-screw or twin-screw melt extrusion because the ultra-high melt viscosity prevents stable plastication; attempts to process on screw machines with uncontrolled shear produce frictional overheating and polymer degradation rather than melt conveying. The sintering mechanism is polymer chain diffusion across particle interfaces, not true melt flow. Die length-to-diameter ratios are normally between 6:1 and 12:1 to maintain consolidation pressure; longer dies raise output but increase friction and require higher ram pressure.
ER-25 is specified for dry sliding wear applications where the combination of low surface energy and high molecular weight reduces adhesive wear and protects mating metal surfaces. In sand-slurry abrasion testing under ISO 15527, unfilled UHMWPE typically exhibits volume loss lower than that of unfilled HDPE by a factor of three to four; however, the absolute value depends on slurry composition, impeller speed, and test duration. The dry coefficient of friction against polished steel measured under ASTM G99 is commonly 0.10 to 0.22, and the material does not exhibit stick-slip behavior at surface pressures below 2 MPa. At low temperature, impact resistance remains high; notched Charpy tests per ISO 179-1/1eA at -196 °C may still exceed 20 kJ/m², although specimen geometry and molded density influence results. These properties make ER-25 suitable for chain guides, conveyor wear strips, star wheels, pump volute liners, and marine fender pads. The operational temperature range for continuous service is usually -250 °C to 90 °C; excursions above 90 °C under load reduce creep resistance and accelerate wear.
In bulk solids handling, ER-25 liners with thickness from 12 to 25 mm are installed in hoppers, silos, and transfer chutes to reduce arching and rat-holing. The low coefficient of friction improves mass flow, but the service temperature limit of 90 °C prevents use in hot-mix asphalt chutes unless ceramic-filled grades are selected. In marine fender applications, water absorption below 0.01 % under ISO 62 maintains dimensional stability. Machining of ER-25 stock shapes uses carbide or diamond tooling at cutting speeds between 200 and 500 m/min; compressed air is recommended for chip evacuation because low thermal conductivity can cause local melting at high feed rates. The linear thermal expansion coefficient under ISO 11359-2 is between 1.5 × 10⁻⁴ K⁻¹ and 2.5 × 10⁻⁴ K⁻¹. For outdoor installations experiencing a 40 °C temperature swing, a 1 m strip may expand by 6 to 10 mm; fastening with slotted holes or countersunk bolts prevents buckling. Thermal conductivity is approximately 0.40 W/(m·K) under ISO 22007-2, so frictional heat is not quickly dissipated and sliding speed must be limited to keep surface temperature below the 90 °C service ceiling.
Compared with conventional high-density polyethylene, ER-25 differs primarily in molecular weight, melt rheology, and wear behavior. HDPE with melt flow rates of 0.2 to 20 g/10 min under ISO 1133-1 can be injection molded and screw-extruded, but it develops significantly higher abrasion loss and lower notched impact strength. UHMWPE ER-25 has no measurable melt flow and requires pressure-assisted sintering; this processing constraint is offset by increased wear life in particulate-laden environments and higher low-temperature toughness. Additivated UHMWPE grades, including crosslinked, oil-filled, glass-filled, and anti-static versions, occupy separate niches. Crosslinked UHMWPE improves creep resistance and wear in orthopaedic bearing inserts but sacrifices ductility and cannot be re-processed by sintering. Oil-filled UHMWPE reduces friction in starved lubrication but may exude oil at elevated temperature and is less suitable for food-contact applications. Glass-filled UHMWPE raises modulus and dimensional stability but increases mating-surface abrasion and lowers impact strength. ER-25, as a virgin unfilled grade, should be selected when chemical purity, low friction, and high ductility take precedence over stiffness or static dissipation. Compared with PTFE, ER-25 offers lower maximum continuous service temperature and lower chemical inertness but better abrasion resistance in particulate-laden systems; PTFE remains the preferred choice only in high-temperature chemical service above 90 °C.
| Material/grade | Melt flow rate (ISO 1133-1) | Processing route | Relative advantages | Main limitation |
| ER-25 UHMWPE | < 0.01 g/10 min | Ram extrusion, compression molding, sintering | High sand-slurry abrasion resistance, no-break impact | Not screw melt-processable |
| HDPE | 0.2–20 g/10 min | Injection molding, screw extrusion | High-output melt processing | Lower abrasion and impact performance |
| Crosslinked UHMWPE | Not measurable | Compression molding | Improved creep and wear in orthopaedic bearings | Reduced ductility, not re-processable |
| Oil-filled UHMWPE | Not measurable | Ram extrusion/compression molding | Lower start-up friction | Oil exudation, food-contact constraints |
| Glass-filled UHMWPE | Not measurable | Compression molding | Higher stiffness, lower thermal expansion | Mating-surface abrasion, reduced impact |
Virgin UHMWPE is an electrical insulator with volume resistivity above 10¹⁴ Ω·cm and surface resistivity above 10¹² Ω under ASTM D257. In explosive dust environments, static accumulation may require anti-static UHMWPE or external grounding; ER-25 as an unfilled grade is not appropriate for static-dissipative service without additional measures. The polymer resists dilute acids and alkalis at room temperature but is attacked by strong oxidizing media such as fuming nitric acid and hot sulfuric acid. Contact with aliphatic and aromatic hydrocarbons can induce swelling and reduce dimensional stability in oily environments; oil-filled UHMWPE may reduce friction but is subject to exudation and food-contact restrictions. Contact with copper, copper alloys, and transition-metal salts at processing temperatures should be avoided because these species catalyze thermo-oxidative degradation. Additives containing pro-oxidant or amine-based stabilizers should be reviewed against the virgin grade’s thermal stabilizer package before dry blending.
Regulatory and handling constraints for ER-25 require confirmation against the supplier’s current documentation. For food-contact applications, unfilled UHMWPE may comply with FDA 21 CFR 177.1520 for olefin polymers and with Commission Regulation (EU) No 10/2011 on plastic materials intended to come into contact with food, provided migration limits are met under the intended use. Industrial grades are typically accompanied by a REACH declaration according to Regulation (EC) No 1907/2006 and a RoHS conformity statement under Directive 2011/65/EU; these declarations are shipment-specific. ER-25 is incompatible with strong oxidizing acids, free halogen environments, and chlorinated solvents at elevated temperature, which cause surface cracking or depolymerization. Aromatic hydrocarbons can induce swelling and dimensional change. The powder is sensitive to ultraviolet exposure; outdoor stock shapes should be compounded with UV stabilizers or shielded from direct sunlight. Storage should remain below 40 °C and below 60 % relative humidity, away from ignition sources, with nitrogen purging not required for standard warehousing. Published data for ER-25-specific performance in some non-standard wear environments is limited; qualification testing under the intended service condition is required before substitution into critical load-bearing systems.
