Evonik VESTAKEEP® 4000G PEEK

Product Overview

• Manufacturer：Evonik (Evonik Industries, headquartered in Essen, Germany; one of the world’s leading specialty chemicals companies)
• Category：Polyetheretherketone (PEEK), belonging to the polyaryletherketone (PAEK) family; semi-crystalline thermoplastic engineering plastic; unfilled
• Appearance：Granule form, natural (uncolored); supplied by the manufacturer in 25 kg boxes with moisture-proof polyethylene liners
• Viscosity positioning：The higher-viscosity tier among the five VESTAKEEP® viscosity series (1000 / 2000 / 3000 / 4000 / 5000); 4000G is a general-purpose unreinforced grade suitable for both injection molding and extrusion
• Key application fields：Automotive drivetrain and sealing parts, sterilizable medical components, semiconductor and electrical/electronic parts, food contact equipment, aerospace, oil & gas and chemical processing

VESTAKEEP® 4000G is an unfilled polyetheretherketone (PEEK) granule introduced by Evonik for high-end engineering applications, positioned as a general-purpose grade in the higher-viscosity range of the PEEK (polyetheretherketone) family. The material is a semi-crystalline thermoplastic containing no glass-fiber or carbon-fiber reinforcement, and therefore retains the matrix resin’s toughness, dielectric insulation and chemical inertness while offering an exceptionally high thermal ceiling: a melting point of approximately 340 °C and Vicat softening temperatures of 305 °C (Method B) / 335 °C (Method A), leaving substantial safety margin for high-temperature service.

Process compatibility is the core value of this grade. The manufacturer recommends a melt temperature of 370–380 °C and a mold temperature of 160–200 °C (preferably 180 °C) for injection molding; its relatively high melt viscosity also delivers stable performance in extrusion (rod, tube, sheet and profile), making it one of the few unfilled PEEK grades that works across both injection molding and extrusion.

Industry positioning: The VESTAKEEP® brand stands alongside VICTREX® and KetaSpire® as one of the mainstream supply brands in the global PEEK market. As the representative material for “metal-to-plastic conversion,” PEEK has a density of only 1.30 g/cm³ (about 1/2 that of aluminum and 1/6 that of steel), yet can operate long-term under temperatures above 250 °C, aggressive chemical media and high loads — which is precisely why 4000G is widely used to replace precision parts made of copper, aluminum and stainless steel. As a global polymer raw material supplier with more than 20 years of experience, ZiJun Plastics supports PEEK materials with original TDS, MSDS and batch COA documentation, and accommodates small-lot sample verification.

Technical Data Sheet (TDS)

Physical Properties

Mechanical Properties

Thermal Properties

Electrical Properties

The technical data sheet (TDS) of VESTAKEEP® 4000G PEEK material from Evonik corporation, if there are differences, please refer to the official website of Evonik.

Features & Benefits of VESTAKEEP® 4000G

• Exceptionally high thermal ceiling for long-term high-temperature service: Melting point 340 °C (ISO 11357-3) and Vicat softening temperatures of 305 °C (Method B) / 335 °C (Method A), with far greater thermal headroom than conventional engineering plastics such as PA, POM and PBT, allowing structural and wear parts to function above 250 °C.
• Unfilled and high-viscosity: one grade for both injection molding and extrusion: With no reinforcing fibers, a melt temperature window of 370–380 °C and a mold temperature of 160–200 °C (preferably 180 °C), it handles thick-walled structural parts as well as extruded rod, tube, sheet and profile — reducing the validation cost of switching grades within one project.
• Excellent chemical resistance and hydrolysis resistance: Except for strongly oxidizing media such as concentrated sulfuric acid, it remains stable in the vast majority of organic solvents, acidic and alkaline media and high-temperature steam — without swelling or degradation — making it suitable for seals and valve components in chemical and oil & gas environments.
• A balanced configuration of stiffness and toughness: Tensile modulus of 3500 MPa and yield strength of 96 MPa, together with a tensile strain at break of 30%; Charpy unnotched impact strength is No Break at both -30 °C and 23 °C, while notched impact values are 6 and 7 kJ/m² respectively, giving better low-temperature embrittlement resistance than most unfilled engineering plastics.
• Inherent flame retardancy and a high electrical insulation class: UL 94 V-0 (3.2 mm, without added flame retardants), Glow-Wire Flammability Index GWFI 960 °C (2 mm) and Glow-Wire Ignition Temperature GWIT 825 °C (2 mm); volume resistivity of 1.0E+15 Ω·cm, dielectric strength of 16 kV/mm and CTI of 200 V meet the insulation requirements of high-voltage and high-frequency electrical parts.
• Good dimensional stability and low water absorption: Mold shrinkage of 0.9% (parallel) / 1.1% (transverse), combined with low moisture uptake, keeps precision parts within stable fit tolerances under alternating hot and humid conditions.
• A clear food contact compliance basis: This grade has a food contact compliance basis under EU 10/2011 and FDA 21 CFR §177.2415, and can be used for contact parts of food processing and filling equipment (compliance statements for specific batches are subject to Evonik’s official documents and COA).

Applications

• Automotive Industry：Leveraging its low density of 1.30 g/cm³ and high specific strength, VESTAKEEP® 4000G is commonly used for metal-to-plastic drivetrain and sealing parts: gears, bearing cages, thrust washers, seal rings, clutch components and high-temperature brackets around the engine. Compared with metal parts, it simultaneously reduces weight, lowers the coefficient of friction and eliminates the need for lubricant maintenance.
• Medical & Laboratory Equipment：The material withstands autoclave (steam) sterilization, ethylene oxide (EtO) and irradiation sterilization, making it suitable for surgical instrument handles and structural parts, endoscope components, dental instruments, and chemical-resistant fixtures and accessories in laboratories. Important note: 4000G is an industrial general-purpose grade and is not recommended for long-term human implantation (>30 days); implantable and medical device PEEK should use medical grades from the VESTAKEEP® i series, with ISO 10993 / USP Class VI biocompatibility documentation requested.
• Semiconductor, Electrical & Electronics：Drawing on its high-temperature dimensional stability and high insulation performance, it is used in wafer carriers, CMP retaining rings, high-precision connectors, relay and switch parts, SMT fixtures and high-temperature-resistant insulating structural parts; the combination of CTI 200 V and UL 94 V-0 meets demanding electrical safety and flame-retardancy requirements.
• Food & Beverage Processing Equipment：With a compliance basis under EU 10/2011 / FDA 21 CFR §177.2415, it is used for pump and valve liners, wear-resistant bushings, guide rails and conveyor components on filling lines, and food-grade seals — combining resistance to cleaning agent corrosion with high-temperature steam disinfection.
• Aerospace：Suitable for aircraft interior brackets, structural fittings and wire harness clamps that must simultaneously meet flame retardancy, low smoke, chemical resistance and lightweight requirements; a mature approach to lightweighting metal parts.
• Industrial Machinery, Oil & Gas and Chemical Processing：Its high viscosity makes it well suited to extruded rod and sheet that is subsequently machined, for compressor valve plates, oil-free lubricated bearings, seals, wear-resistant bushings, pump and valve components, and downhole tool parts — maintaining a long service life under corrosive media and high-temperature, high-pressure conditions.

Frequently Asked Questions (FAQs)

Q1: Does VESTAKEEP® 4000G need drying before processing? What injection molding parameters are recommended?

Yes. Although PEEK has very low moisture absorption, granules still adsorb trace moisture on their surface in humid environments; feeding them directly into a barrel above 370 °C can cause silver streaks, bubbles and polymer chain degradation through hydrolysis. Recommended practice: use a desiccant (dehumidifying) dryer at 150–160 °C for 3–4 hours (adjust the duration according to ambient humidity and equipment capability).

For molding parameters, Evonik recommends a melt temperature of 370–380 °C and a mold temperature of 160–200 °C (preferably 180 °C) for 4000G; a high mold temperature helps achieve sufficient crystallinity and thereby stabilizes mechanical strength and dimensional accuracy. For drying, mold temperature control and troubleshooting of common defects with unfilled PEEK, see our technical article “Drying and Mold Temperature Control for Unfilled PEEK“. Optimal parameters vary with the machine and part geometry, so a mold trial is recommended before mass production.

Q2: How should VESTAKEEP® 4000G be selected compared with other unfilled PEEK grades?

The key difference is melt viscosity: 4000G is a higher-viscosity grade with lower flowability than low-viscosity grades (1000/2000 series). For thin-walled parts, long flow-length ratios or fine micro-features, low-viscosity grades should be evaluated first; for thick-walled parts and extruded profiles, or where higher melt strength and impact toughness are required, 4000G has the advantage. The following is a comparable side-by-side reference between this page’s data and a comparable grade on our site (both are typical values from each supplier’s published TDS):

As the comparison shows, the two are broadly equivalent in density, impact strength and shrinkage; 450G is slightly higher in tensile modulus and elongation at break, and its flowability better suits thin-walled precision injection molding, while 4000G reaches a CTI of 200 V, giving it an edge in electrical parts that are sensitive to tracking. Final selection should still be based on part service conditions, mold structure and cost; you can review the full property table of VICTREX® PEEK 450G on our site for an item-by-item comparison.

Q3: Does VESTAKEEP® 4000G meet UL, RoHS and other compliance requirements? Can it be used in food contact or medical applications?

• Flame retardancy / UL: Under the UL 94 standard, this grade achieves a V-0 rating at 3.2 mm thickness (without added flame retardants), and shows glow-wire performance of GWFI 960 °C / GWIT 825 °C (2 mm). For the specific UL file number and thickness classifications on the Yellow Card, refer to Evonik’s official UL certification documents.
• RoHS / REACH: Unfilled PEEK is a high-purity aromatic polymer and does not contain the lead, cadmium, mercury, hexavalent chromium, PBB, PBDE or phthalate plasticizers restricted by the RoHS Directive, and generally satisfies RoHS and REACH requirements; the formal compliance conclusion should be based on the Declaration of Conformity (DoC) issued by Evonik and the batch COA.
• Food contact: This grade has a food contact compliance basis under EU 10/2011 and FDA 21 CFR §177.2415, and is suitable for contact parts of food processing equipment.
• Medical: This must not be taken to imply suitability for implantable devices. For medical devices — especially long-term implants — use medical-grade VESTAKEEP® i series grades and require ISO 10993 biocompatibility test reports from the supplier.

Q4: In cross-border procurement, how can I confirm that VESTAKEEP® 4000G is genuine original material and keep procurement costs under control?

A three-step verification is recommended: ① Packaging and labelling — original material is supplied in 25 kg boxes with moisture-proof PE liners, and the packaging labels, batch numbers and original documents must be consistent; ② Closed documentation loop — obtain the original TDS, MSDS and batch COA, and check whether easily re-testable indicators such as density (1.30 g/cm³) and MVR (11 cm³/10 min at 380 °C/5 kg) match the batch’s measured values; ③ Small-lot validation — run sample injection molding and re-test key properties before committing to long-term supply.

PEEK is a high-unit-price specialty engineering plastic whose price is markedly influenced by crude oil, monomer costs and plant maintenance cycles, so procurement cadence and inventory strategy have a significant effect on cost. For the current price range and supply outlook, see our market analysis “2026 PEEK Resin Prices and Supply Trends“; for samples of 4000G, volume quotations or alternative grade recommendations, please contact our technical sales team.