Purity & impurity profile
Request the agreed assay method, fumaric acid limit, and any additional impurity controls.
Unsaturated dicarboxylic acid
Maleic Acid
Maleic acid is an intermediate used in the manufacture of lubricant additives, plasticizers, resins, surface coatings, and agricultural chemicals.
CAS number110-16-7
Molecular formulaC4H4O4
Molecular weight116.07 g/mol
Physical formSolid
Chemical reference
Know your material.
Maleic acid is the cis isomer of butenedioic acid. Its two carboxylic acid groups and carbon–carbon double bond make it a useful intermediate in industrial chemistry. Chemstock’s published applications include resins, surface coatings, lubricant additives, and plasticizers.
- IUPAC name
- (Z)-but-2-enedioic acid
- EC number
- 203-742-5
- Common names & synonyms
- cis-Butenedioic acid · (Z)-But-2-enedioic acid
- Chemical family
- Unsaturated dicarboxylic acid
- PubChem CID
- 444266 ↗
- InChIKey
- VZCYOOQTPOCHFL-UPHRSURJSA-N
Reference physical properties
Substance reference values, separate from the supplied-grade specification. Conditions and source are shown so your technical team can interpret the data.
| Property | Reference value | Conditions / source |
|---|---|---|
| Appearance | White crystals | Substance reference; supplied particle form is grade-specific. [2] |
| Melting point | 131 °C | Reference value; see the separate published specification range below. [2] |
| Relative density | 1.59 | Relative to water = 1. [2] |
| Water solubility | 78 g/100 mL | At 25 °C. [2] |
| Vapor pressure | 0.0048 Pa | At 25 °C. [2] |
| Thermal behavior | Decomposes at 135 °C | Reference observation, not an operating-temperature recommendation. [2] |
Technical qualification
Typical product specifications.
These are typical limits published in Chemstock’s existing catalogue. The legacy assay label is not evidence of a current USP grade. Obtain the current, agreed specification and test methods for the material being supplied.
| Parameter | Published limit / value | Method / conditions |
|---|---|---|
| Appearance | White crystalline powder | Visual description |
| Assay | 99.0% min. | Confirm analytical method and grade |
| Water | 1.0% max. | Confirm test method |
| Fumaric acid | 1.0% max. | Confirm impurity method |
| Melting range | 130–134 °C | Confirm method and acceptance range |
Qualify against the current specification.
Request the grade-specific technical sheet, analytical methods, and a representative CoA. Batch results belong on the shipment’s certificate of analysis.
Request a technical packageWhat to define with your technical team
Physical form
Specify powder or crystal requirements and any particle-size limits important to feeding or dissolution.
Regulated applications
Identify your end use and required grade. A chemical identity or typical assay does not establish food, pharmaceutical, or other regulated-use suitability.
Application fit
Where it works. What to evaluate.
Resins & surface coatings
Intermediate for resin and coating chemistry.
Qualification focusReview assay, impurity limits, and color requirements against your formulation.
Lubricant additives
Raw material in the manufacture of lubricant additives.
Qualification focusDefine your reaction requirements and maximum water content.
Plasticizers & intermediates
Used in industrial chemical synthesis and plasticizer manufacture.
Qualification focusConfirm that maleic acid, rather than maleic anhydride, is the specified input.
Documentation
The detail behind your approval.
Product documents are available on request. Tell us the required grade and destination so we can identify the right documentation for your review.
On request
Safety data sheet
Current safety, handling, transport, and disposal information for the grade and destination.
Include: Required grade, destination country, and preferred language.Request SDSOn request
Technical specification
Current acceptance limits, physical properties, and the relevant analytical methods.
Include: Your internal specification and required test methods.Request TDS / specificationOn request
Certificate of analysis
Batch-specific results for a supplied lot, or a representative CoA for qualification.
Include: Lot / batch number for an existing shipment; otherwise request a representative CoA.Request CoAOn request
Supplier certifications
Source-specific certification and supporting information for your qualification process.
Include: Required certification, manufacturing site scope, and validity requirements.Request Supplier documentationCertificates apply to a named source, site, grade, or batch. Request the scope and current revision needed for your approval process.
Procurement & logistics
Plan the supply around your operation.
Discuss the source, commercial requirements, and delivery schedule before placing an order.
- Packaging reference
- 100 kg drum listed in the existing catalogue; confirm current pack options.
- Order quantity & annual demand
- Minimum order, trial quantity, forecast volume, and delivery schedule reviewed on request.
- Manufacturing origin & source
- Manufacturer, production site, and country of origin confirmed for the proposed supply.
- Lead time & delivery
- Confirmed against the required destination, quantity, and sourcing option.
- Shelf life & retest
- Request manufacturer storage conditions, shelf life or retest date, and remaining life at dispatch.
Supplier onboarding or a second-source review?
Share your qualification questionnaire, incoming specification, required documentation, and change-notification expectations with our team.
Discuss supplier qualification EHS review
Safety, handling & storage.
This overview supports initial review and does not replace a current SDS, site risk assessment, or grade-specific handling instructions.
Handling considerations
Irritation and sensitization hazards require review. Control dust and use the precautions specified in the supplied SDS. Reference [2]
Storage considerations
Reference guidance calls for dry storage in original packaging, separated from food and feed. Confirm the supplied grade’s conditions and retest period. Reference [2]
Transport review
ICSC lists UN 3261 (n.o.s.), Class 8, Packing Group III. Confirm the actual shipping classification using the current supplier SDS and transport documentation. Reference [2]
Market & supplier qualification
Confirm the requirements for your market.
Applicable requirements depend on the source, destination, and end use. Use this list to identify the statements and evidence your team needs; it is not a claim of certification or regulatory approval.
- Chemical inventory & market access
- TSCA, REACH / UK REACH, or other applicable inventory and importer requirements.
- Restricted-substance declarations
- REACH SVHC, RoHS, Proposition 65, or customer-specific restricted-substance lists, where relevant.
- Application-specific grade
- Food, pharmaceutical, personal-care, or other end-use requirements; confirm the exact standard and grade.
- Origin & sustainability evidence
- Country of origin, feedstock declarations, bio-based evidence, and certifications where required.
- Supplier quality qualification
- Relevant site certifications, questionnaire responses, change-notification expectations, and traceability requirements.
Technical questions
Before you qualify this material.
Is maleic acid the same as maleic anhydride?
No. They are distinct chemicals. Use the chemical name and CAS number 110-16-7 together when specifying maleic acid, and confirm the required material with your technical team.
Why does the melting point differ from the specification range?
A reference value describes a reported property of the substance. A product specification gives acceptance limits for a particular material. Use the agreed supplier specification and method for incoming quality control.
Can you provide test methods and a batch CoA?
Technical documents are available on request. State the product, required grade, and tests you need. For an existing shipment, include the lot number so the batch-specific CoA can be identified.
Sources & information quality
Traceable information.
Reference data checked September 22, 2026. Public references describe the substance; only the current supplier documents establish the specification, certifications, and shipment details for the material you purchase.
- PubChem · CID 444266
Chemical identity, molecular weight, and structure.
- ILO / WHO · ICSC 1186
Reference physical properties, handling, storage, and transport information.
- Chemstock · published product record
Existing typical specifications, applications, and packaging reference.