Is Polyoxyl 35 Castor Oil a single, defined molecule?

No. It is a composition made by reacting castor-oil glycerides with about 35 moles of ethylene oxide. Batch conformance should therefore be judged against the agreed specification and test results, not a single molecular formula or CAS number alone.

Does “Cremophor EL-Type” mean original branded Cremophor EL?

No. “Type” identifies a generic comparison grade; it does not prove equivalence of manufacturer, grade, or process to a named brand. When brand material is required, supplier identity and documentation for that material must be confirmed separately.

What should be compared before using Polyoxyl 35 Castor Oil in a formulation?

For the intended use, review appearance, acid, hydroxyl and saponification values, water, solubilization or emulsification behavior, and relevant impurity limits. In replacement work, assess clarity, viscosity, stability, and compatibility under actual process conditions.

Polyoxyl 35 Castor Oil (Cremophor® EL-Type) CAS 61791-12-6

Polyoxyl 35 castor oil is a nonionic solubilizer and emulsifier produced by reacting castor oil with about 35 moles of ethylene oxide per mole of castor oil. It is a multicomponent UVCB distribution, not one 99%-pure molecule. “Cremophor® EL” is a BASF trademark reference; this page does not claim that a generic grade is BASF material or brand-equivalent.

CAS: 61791-12-6
Synonyms: Polyoxyl 35 castor oil; PEG-35 castor oil; macrogolglycerol ricinoleate; castor oil ethoxylate (approximately 35 EO); Cremophor® EL-type benchmark (not a brand-equivalence claim)
Einecs: 500-151-7
Molecular Formula: UVCB reaction-product distribution of castor oil with approximately 35 moles of ethylene oxide per mole of castor oil. No single molecular formula or molecular weight; C57H104O9(C2H4O)n is only a variable compositional notation.
Grade: Confirm the nominal EO or PO level, feedstock range, active matter, water, physical form and relevant analytical values against the current TDS and COA.
Package: State required quantity, physical form and destination; confirm the current bag or container, liner, net weight, temperature handling and transport requirements before quotation.

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Product Description

1 Technical Specifications

2 Applications

3 Storage

4 Safety / Regulatory

Technical Specifications

Property	Specification
CAS Number	61791-12-6
EC / List No.	500-151-7
Identity / Formula	UVCB reaction-product distribution of castor oil with approximately 35 moles of ethylene oxide per mole of castor oil. No single molecular formula or molecular weight; C57H104O9(C2H4O)n is only a variable compositional notation.
Grade / Specification	Generic Polyoxyl 35 castor oil / PEG-35 castor oil type. Confirm the EO target, identity, acid value, hydroxyl value, saponification value, water, oxidative-quality and microbiological limits on the current specification and COA. Pharmacopoeial or parenteral suitability must be explicitly documented. BY-160 / PEG-60 castor oil is a separate higher-EO grade and is not an equivalent synonym.
Key physical data	A multicomponent nonionic product whose appearance and flow can change with temperature and grade. Use the exact offered grade's TDS/COA for appearance, pH, HLB and handling data; do not copy branded typical values into a generic specification.
Packaging	State required quantity, physical form and destination; confirm the current bag or container, liner, net weight, temperature handling and transport requirements before quotation.

Applications

Evaluate as an oil-in-water emulsifier or solubilizer in compatible oral, topical, personal-care or industrial formulations. Any parenteral use requires an expressly qualified grade, appropriate compendial and microbiological/endotoxin documentation, and validation by the finished-product manufacturer.

Storage

Store in the original compatible, tightly closed container under the temperature conditions stated in the supplied TDS/SDS. Protect from contamination, excessive heat, moisture and incompatible materials. If warming is permitted to restore flow, follow the supplier's controlled-heating and homogenization instructions.

Safety / Regulatory

Use the current supplier SDS, workplace controls and the buyer's risk assessment. A CAS match or “EL-type” description does not establish BASF origin, brand equivalence, pharmacopoeial compliance or parenteral suitability; verify all claims for the exact supplied grade.

FAQ - Technical & Supply Chain

Q:
Is Polyoxyl 35 Castor Oil a single, defined molecule?

A: No. It is a composition made by reacting castor-oil glycerides with about 35 moles of ethylene oxide. Batch conformance should therefore be judged against the agreed specification and test results, not a single molecular formula or CAS number alone.
Q:
Does “Cremophor EL-Type” mean original branded Cremophor EL?

A: No. “Type” identifies a generic comparison grade; it does not prove equivalence of manufacturer, grade, or process to a named brand. When brand material is required, supplier identity and documentation for that material must be confirmed separately.
Q:
What should be compared before using Polyoxyl 35 Castor Oil in a formulation?

A: For the intended use, review appearance, acid, hydroxyl and saponification values, water, solubilization or emulsification behavior, and relevant impurity limits. In replacement work, assess clarity, viscosity, stability, and compatibility under actual process conditions.

Ordering & Documentation

Key information for document requests, quotations, and supply planning.

Documents

COA, TDS, SDS/MSDS and packing details are available on request.

Quotation

Send the CAS number, grade, quantity, packing preference and destination.

Sample & Supply

Support is available for samples, trial orders, bulk and repeat supply.

Storage & Shipping

Product-specific conditions are confirmed before order.

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