PEG 4000, PEG 6000 and PEG 8000: Commercial Grade Selection Guide
Search demand for PEG 4000, PEG 6000, and peg 8000 is buyer intent — tablet binders, detergent waxes, ointment bases, and industrial thickeners — not a tour of ultra-high MW specialty macrogols. This page owns the commercial comparison of those three solid polyethylene glycol grades and adds a short cross-section on PEG-1500 MONOSTEARATE for emulsifier shoppers who land here from ester queries. For PEG 10000 / 20000 and hardness extremes, use the companion high-MW PEG guide; for full PEG portfolio context see Polyethylene glycol.
Why PEG 4000 / 6000 / 8000 are specified as a set
All three are white to off-white solid PEG flakes or powders (CAS 25322-68-3 family) with melting points above typical ambient warehouse temperatures. Buyers step up MW to raise hardness, melt viscosity, and slow dissolution — or step down for easier melt processing and faster aqueous release. Venus Ethoxyethers and Avesta Pharma supply technical and pharmacopoeial channels depending on end use.
PEG 4000 vs PEG 6000 vs PEG 8000 comparison
| Property | PEG 4000 | PEG 6000 | PEG 8000 |
|---|---|---|---|
| Nominal avg. MW (g/mol) | ~3000–4800 (grade-dependent) | ~5400–6600 | ~7000–9000 |
| Physical form (25°C) | Flake / powder | Flake / powder | Flake / powder |
| Melting range (typical) | ~50–58°C | ~55–63°C | ~55–63°C (often slightly harder) |
| Melt viscosity | Lowest of the three | Moderate | Higher |
| Aqueous dissolution | Faster | Intermediate | Slower |
| Hygroscopicity | Low vs liquid PEG | Lower | Lowest of the three |
| Primary buyer uses | Binders, ointments, ceramics, general pharma | Detergent anti-redeposition, binders, lubricants | Pharma excipient, film coating, capsules |
| Venus product focus | Technical / pharma channels | Technical / industrial volume | PEG 8000 dedicated page |
PEG 4000 — the accessible solid workhorse
PEG 4000 is often the first solid PEG specified when formulators leave liquid PEG 400 / 600 behind. Lower melt viscosity eases hot-melt granulation, ointment compounding, and ceramic binder burnout. In pharmaceuticals it appears as a binder, ointment/suppository component (blended with other MW), and tablet coating plasticizer at moderate levels.
Industrial buyers use PEG 4000 in mould-release aids, water-soluble lubricants, and as a processing aid where complete water rinse-off is required. Relative to PEG 8000, PEG 4000 dissolves faster in aqueous media — useful when rapid release is desired.
PEG 6000 — detergent and industrial balance
PEG 6000 sits between PEG 4000 and PEG 8000 in hardness and dissolution. Large-volume detergent and cleaning formulators value PEG 6000 as an anti-redeposition / soil-suspension aid and as a solid binder in bars and powders. Metalworking and specialty wax blends use PEG 6000 when PEG 4000 is too soft and PEG 8000 is over-specified for cost.
Pharma use exists where monographs and customer qualifications allow, but PEG 8000 often carries broader oral solid dossier familiarity. Confirm pharmacopoeial listing and impurity limits for drug applications.
PEG 8000 — pharmaceutical and premium solid PEG
peg 8000 / PEG 8000 (macrogol 8000 in many pharmacopoeias) is the commercial solid grade most frequently locked into oral solid dosage forms: wet granulation binder, film-coating plasticizer, capsule lubricant, and hot-melt carrier component. Product detail: PEG 8000.
- Established USP / Ph. Eur. / IP monograph pathways (verify current edition for your market)
- Balance of melting point and processability versus PEG 4000 (softer) and PEG 20000 (much harder)
- Preferred when audit, DMF, and change-control documentation are mandatory
Stability considerations in drug products: PEG pharma stability. Ultra-high MW context: high-MW PEG guide.
How this page differs from the high-MW PEG guide
The high-MW guide emphasizes PEG 8000 together with PEG 10000 and PEG 20000 for hardness, tropical suppositories, and maximum-MW industrial wax. This page is the commercial search landing for buyers comparing PEG 4000 vs PEG 6000 vs PEG 8000 on melting, cost-in-use, and pharma-versus-technical grade choice. Cross-link both when your SKU list spans the full solid range.
Pharma vs technical grade buying checklist (2026)
| Check | PEG 4000 | PEG 6000 | PEG 8000 |
|---|---|---|---|
| Need monograph + DMF path | Available in pharma channel | Confirm monograph | Most common pharma solid |
| Detergent / industrial volume | Good | Excellent cost/performance | Use if hardness required |
| Easy melt processing | Best | Good | Needs higher process temp |
| Slow aqueous dissolution | Least | Mid | Most of the three |
PEG-1500 MONOSTEARATE — emulsifier cross-section
Buyers searching solid PEG grades sometimes also need PEG-1500 MONOSTEARATE — an ester emulsifier / thickener formed from PEG ~1500 and stearic acid, not a free polyethylene glycol wax. It functions as an O/W emulsifier and viscosity builder in creams, lotions, and some industrial emulsions.
Do not substitute PEG 1500 polymer for PEG-1500 monostearate (or vice versa). For ester selection, HLB, and cream examples, see PEG stearate emulsifiers guide. Glycol and glycerol ester hubs are linked from Venus ester pages.
Processing tips for solid PEG 4000–8000
- Wet granulation — dissolve or melt PEG, add to powder bed; dry to LOD target
- Hot-melt — set barrel/jacket above melting range; avoid oxidizing atmospheres for sensitive APIs
- Film coating — PEG 8000 as plasticizer in HPMC/acrylic dispersions
- Storage — sealed, dry warehouse; flakes can cake if humid — gentle warming restores flow
Related Venus PEG resources
Blending PEG 4000 with PEG 6000 or PEG 8000
Solid PEG grades are mutually compatible. Blending PEG 4000 with peg 8000 tunes melting point and dissolution for ointment and suppository bases: higher PEG 4000 share softens and speeds release; higher PEG 8000 share hardens and slows dissolution. PEG 6000 is a practical middle component when a two-grade blend overshoots either softness or cost.
Confirm blend melting by DSC or capillary method when product performance is temperature-critical (tropical shipping, body-temperature release). Approximate weight averaging of melt points is a starting estimate only.
RFQ language that gets the right grade
- State PEG 4000 / PEG 6000 / PEG 8000 explicitly — do not write only “solid PEG”
- Declare pharma vs technical channel and target pharmacopoeia
- Specify flake vs powder preference and packaging
- List impurity limits (EG/DEG, metals, residual EO) if tighter than default COA
- If you need PEG-1500 MONOSTEARATE, say “ester emulsifier” so it is not fulfilled as PEG polymer
Related Venus PEG resources
Hub: Polyethylene glycol. Product: PEG 8000. High MW: high-MW PEG guide. Esters: PEG stearate emulsifiers. Request COA and samples via contact Venus.