Maleic acid
CAS 110-16-7
EC 203-742-5
Formula C4H4O4
MW 116.07 g/mol
Organic Acids Food & NutritionPharmaceuticals & HealthcarePersonal Care & Cosmetics Preservation & BiocidepH Regulation & BufferingFlavoring & Acidulant
Description
Maleic acid (CAS 110-16-7) is a dicarboxylic organic acid also known as toxilic acid, maleinic acid, and cis-butenedioic acid. It carries no assigned E-code and is commercially identified under EC number 203-742-5 with molecular formula C4H4O4.
In pharmaceutical formulations, maleic acid acts as a pH buffer and acidulant, stabilising active ingredients within a defined pH window. Personal care chemists use it in hair straightening and smoothing treatments, where it reforms disulfide bonds to restructure the hair fibre. In food applications, it functions as a flavour modifier by contributing a sharp, clean acidity to beverages and confectionery.
Maleic acid is available in technical and pharmaceutical grades, with the latter conforming to Ph.Eur. and FCC monographs. The substance is registered under REACH and supplied as a crystalline powder in 25 kg bags or bulk quantities. Procurement teams should confirm grade specification against intended application prior to ordering.
In pharmaceutical formulations, maleic acid acts as a pH buffer and acidulant, stabilising active ingredients within a defined pH window. Personal care chemists use it in hair straightening and smoothing treatments, where it reforms disulfide bonds to restructure the hair fibre. In food applications, it functions as a flavour modifier by contributing a sharp, clean acidity to beverages and confectionery.
Maleic acid is available in technical and pharmaceutical grades, with the latter conforming to Ph.Eur. and FCC monographs. The substance is registered under REACH and supplied as a crystalline powder in 25 kg bags or bulk quantities. Procurement teams should confirm grade specification against intended application prior to ordering.
Physical Properties
| Melting Point | 131 °C |
| Boiling Point | 138 °C |
| Density | 1.590 g/cm³ @ Temp: 20 °C |
| Flash Point | 127 °C |
| Appearance | Maleic acid is a white crystalline solid. Faint, acid like odor. |
| Color | White |
| Odor | Faint odor |
| Form | Powder/Solid |
| Water Solubility | 790 g/L (25 ºC) |
| Vapor Pressure | 0.001Pa at 20℃ |
| Refractive Index | 1.5260 (estimate) |
| pH | 1.3 (100g/l, H2O, 20℃) |
| Log P | -1.3 at 20℃ |
Safety & Handling (Learn More)
Warning GHS07 GHS05 GHS08
H
H302H312H315H317H318H319H335H370H402
P
P260P261P264P270P271P272P273P280P317P319P321P330P405P501P264+P265P301+P317P302+P352P304+P340P308+P316P332+P317P333+P317P337+P317P362+P364P403+P233P305+P351+P338P305+P354+P338
Trade & Regulatory
| HS Code | 29171900 |
| Storage Class | 8A - Combustible corrosive hazardous materials |
| WGK (Germany) | 1 |
Other Names
(Z)-but-2-enedioic acidToxilic acidMaleinic acidACIDUM MALEICUMBUTENEDIOIC ACIDCIS-BUTENEDIOIC ACID
Related Products
Raw Materials
Derivatives
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