Methyl ethyl ketone peroxide

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  • Identifiers

    CAS number
    1338-23-4

    Molecular formula
    C8H18O6

    SMILES
    CCC(C)(OO)OOC(C)(CC)OO

    Safety labels

    Flammable
    Flammable

    Corrosive
    Corrosive

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Fruity 55.52%
    Buttery 34.99%
    Odorless 34.27%
    Ethereal 32.36%
    Sweet 31.38%
    Alcoholic 25.81%
    Milky 21.53%
    Caramellic 20.62%
    Creamy 19.67%
    Fresh 18.46%

     

    Flavor
    Fruity 43.89%
    Bitter 39.7%
    Green 33.08%
    Sweet 31.81%
    Creamy 29.43%
    Musty 28.13%
    Fatty 27.35%
    Fruit 26.14%
    Mild 24.82%
    Alcoholic 24.45%

     

    Odor impact est.
    Medium

  • Properties

    XLogP3-AA
    1.3

    pKa est.
    10.25 (weak base)

    Molecular weight
    210.22 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Slow

    Boiling point

    • 244 °F at 760 mmHg (Decomposes) (NIOSH, 2024)
    • 19 °C
    • 244 °F (decomposes)
    • 244 °F (Decomposes)

    Flash point

    • 88.5 ˚C est.
    • 180 °F (NTP, 1992)
    • 180 °F
    • 125-200 °F for 60% MEKP (open cup)
    • (oc) 125-200 °F (60% MEKP)

    Solubility expt.

    • 1 to 5 mg/mL at 72 °F (NTP, 1992)
    • Partially miscible in water; completely miscible with most organic solvents
    • Solubility in water: very poor
    • Soluble

  • Synonyms

    • 2-BUTANONE PEROXIDE
    • 1338-23-4
    • Methyl ethyl ketone peroxide
    • Thermacure
    • Ketonox
    • Mepox
    • Esperfoam FR
    • Lupersol DEL
    • Butanox LPT
    • 2-butanoneperoxide
    • Quickset super
    • MEKP
    • Quickset Extra
    • 2-Butanone, peroxide
    • Lucidol delta X
    • MEK peroxide
    • Kayamek A
    • Kayamek M
    • Lupersol DDM
    • Lupersol DNF
    • Lupersol DSW
    • Lupersol delta X
    • Permek G
    • Permek N
    • Sprayset MEKP
    • Chaloxyd MEKP HA 1
    • Lucidol DDM 9
    • Lupersol DDA 30
    • Trigonox M 50
    • Butanox M 50
    • MEKPO
    • Butanox M 105
    • Ethyl methyl ketone peroxide
    • HI-Point PD-1
    • HI-Point 90
    • Chaloxyd MEKP-HA 1
    • Chaloxyd MEKP-LA 1
    • HI-Point 180
    • Superox 46-710
    • RCRA waste number U160
    • Methylethylketonhydroperoxide
    • Methyl ethyl ketone hydroperoxide
    • NCI-C55447
    • FR 222
    • W2545087UL
    • DTXSID1024671
    • RefChem:817745
    • DTXCID104671
    • 2-((2-hydroperoxybutan-2-yl)peroxy)butane-2-peroxol
    • 215-661-2
    • 2-hydroperoxy-2-(2-hydroperoxybutan-2-yldioxy)butane
    • 2-hydroperoxy-2-(2-hydroperoxybutan-2-ylperoxy)butane
    • CCRIS 6216
    • HSDB 4181
    • EINECS 215-661-2
    • RCRA waste no. U160
    • UNII-W2545087UL
    • methyl ehtyl ketone peroxide
    • SCHEMBL15306
    • 2-Butanone peroxide, technical
    • CHEMBL1562553
    • 2,2'-Peroxydi(butane-2-peroxol)
    • 2-BUTANONE PEROXIDE [HSDB]
    • AKOS015914484
    • NCGC00091754-01
    • NCGC00091754-02
    • NS00009405
    • A806682
    • Q2914590
    • 2-(dioxidanyl)-2-[2-(dioxidanyl)butan-2-ylperoxy]butane
    • Ethyl methyl ketone peroxide, Methyl ethyl ketone peroxide
    • 2-Butanone peroxide solution, ~32 wt. % in phthalate-free plasticizer mixture
    • 2-Butanone peroxide solution, ~35 wt. % in 2,2,4-trimethyl-1,3-pentanediol diisobutyrate
    • 1338-23-4

  • Applications

    Methyl ethyl ketone peroxide (CAS 1338-23-4) is a reactive organic peroxide used primarily as a free-radical initiator to cure polyester- and vinyl ester-based resins. In industrial manufacturing, it is employed to initiate polymerization in unsaturated polyester resins used for fiberglass-reinforced plastics (FRP), gel coats, and marine or automotive coatings, often with cobalt accelerators. It is also used as a curing agent in certain solvent-based coatings and adhesives systems that rely on peroxide initiation, and may be evaluated for use in specialty resin systems such as laminates and composites. Given safety considerations and regulatory constraints, handling and formulation are subject to local regulations and limits.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 1661.39
    methanol 2306.59
    isopropanol 1518.01
    water 12.9
    ethyl acetate 2953.69
    n-propanol 1254.5
    acetone 5459.13
    n-butanol 1030.25
    acetonitrile 3436.2
    DMF 5240.05
    toluene 1690.22
    isobutanol 1096.74
    1,4-dioxane 4641.69
    methyl acetate 3761.92
    THF 4297.08
    2-butanone 3717.69
    n-pentanol 953.28
    sec-butanol 1515.57
    n-hexane 254.12
    ethylene glycol 267.97
    NMP 5128.27
    cyclohexane 659.68
    DMSO 5078.16
    n-butyl acetate 1148.37
    n-octanol 459.25
    chloroform 7153.9
    n-propyl acetate 1953.36
    acetic acid 2961.75
    dichloromethane 7066.73
    cyclohexanone 5134.71
    propylene glycol 330.52
    isopropyl acetate 1514.65
    DMAc 5519.38
    2-ethoxyethanol 1950.67
    isopentanol 957.1
    n-heptane 96.0
    ethyl formate 2190.52
    1,2-dichloroethane 4032.65
    n-hexanol 488.47
    2-methoxyethanol 2447.98
    isobutyl acetate 788.08
    tetrachloromethane 1157.82
    n-pentyl acetate 869.97
    transcutol 2735.41
    n-heptanol 311.29
    ethylbenzene 1202.39
    MIBK 1101.41
    2-propoxyethanol 984.93
    tert-butanol 1902.63
    MTBE 2207.83
    2-butoxyethanol 708.48
    propionic acid 1858.41
    o-xylene 1304.94
    formic acid 1283.72
    diethyl ether 2031.94
    m-xylene 869.8
    p-xylene 2000.76
    chlorobenzene 2046.11
    dimethyl carbonate 993.26
    n-octane 64.81
    formamide 2727.78
    cyclopentanone 4809.8
    2-pentanone 2348.98
    anisole 2095.42
    cyclopentyl methyl ether 1913.09
    gamma-butyrolactone 5723.75
    1-methoxy-2-propanol 1597.08
    pyridine 4103.3
    3-pentanone 2066.44
    furfural 4739.69
    n-dodecane 52.75
    diethylene glycol 647.92
    diisopropyl ether 557.63
    tert-amyl alcohol 1793.59
    acetylacetone 3220.62
    n-hexadecane 62.22
    acetophenone 2450.72
    methyl propionate 2150.39
    isopentyl acetate 929.15
    trichloroethylene 7672.42
    n-nonanol 402.86
    cyclohexanol 1633.09
    benzyl alcohol 1450.72
    2-ethylhexanol 386.41
    isooctanol 279.15
    dipropyl ether 584.76
    1,2-dichlorobenzene 1983.22
    ethyl lactate 608.94
    propylene carbonate 2622.85
    n-methylformamide 3021.67
    2-pentanol 830.69
    n-pentane 194.15
    1-propoxy-2-propanol 618.24
    1-methoxy-2-propyl acetate 931.87
    2-(2-methoxypropoxy) propanol 710.43
    mesitylene 514.49
    ε-caprolactone 4017.0
    p-cymene 362.44
    epichlorohydrin 5198.14
    1,1,1-trichloroethane 4171.23
    2-aminoethanol 555.97
    morpholine-4-carbaldehyde 4592.37
    sulfolane 5181.89
    2,2,4-trimethylpentane 138.08
    2-methyltetrahydrofuran 3716.37
    n-hexyl acetate 1200.53
    isooctane 60.5
    2-(2-butoxyethoxy)ethanol 894.45
    sec-butyl acetate 1128.17
    tert-butyl acetate 1344.74
    decalin 275.27
    glycerin 455.99
    diglyme 2494.52
    acrylic acid 1575.55
    isopropyl myristate 395.76
    n-butyric acid 2042.06
    acetyl acetate 2077.7
    di(2-ethylhexyl) phthalate 336.95
    ethyl propionate 1777.45
    nitromethane 7884.69
    1,2-diethoxyethane 1296.83
    benzonitrile 1964.63
    trioctyl phosphate 244.68
    1-bromopropane 2116.13
    gamma-valerolactone 6728.64
    n-decanol 267.85
    triethyl phosphate 517.18
    4-methyl-2-pentanol 411.45
    propionitrile 1944.9
    vinylene carbonate 2579.97
    1,1,2-trichlorotrifluoroethane 2949.85
    DMS 1137.37
    cumene 660.45
    2-octanol 303.1
    2-hexanone 1844.34
    octyl acetate 514.22
    limonene 543.48
    1,2-dimethoxyethane 4277.65
    ethyl orthosilicate 450.36
    tributyl phosphate 355.02
    diacetone alcohol 1190.53
    N,N-dimethylaniline 1277.69
    acrylonitrile 2511.69
    aniline 1525.39
    1,3-propanediol 975.49
    bromobenzene 2259.1
    dibromomethane 4449.98
    1,1,2,2-tetrachloroethane 6014.17
    2-methyl-cyclohexyl acetate 784.18
    tetrabutyl urea 471.08
    diisobutyl methanol 238.27
    2-phenylethanol 757.12
    styrene 1485.54
    dioctyl adipate 648.26
    dimethyl sulfate 1790.05
    ethyl butyrate 1047.66
    methyl lactate 731.45
    butyl lactate 531.83
    diethyl carbonate 778.65
    propanediol butyl ether 583.36
    triethyl orthoformate 644.07
    p-tert-butyltoluene 324.97
    methyl 4-tert-butylbenzoate 952.48
    morpholine 4518.4
    tert-butylamine 1162.16
    n-dodecanol 197.78
    dimethoxymethane 2301.78
    ethylene carbonate 2128.86
    cyrene 994.0
    2-ethoxyethyl acetate 1136.64
    2-ethylhexyl acetate 751.3
    1,2,4-trichlorobenzene 2352.44
    4-methylpyridine 4680.41
    dibutyl ether 731.42
    2,6-dimethyl-4-heptanol 238.27
    DEF 3011.39
    dimethyl isosorbide 1278.43
    tetrachloroethylene 4149.62
    eugenol 773.47
    triacetin 1264.97
    span 80 564.19
    1,4-butanediol 467.76
    1,1-dichloroethane 4149.38
    2-methyl-1-pentanol 910.72
    methyl formate 2643.36
    2-methyl-1-butanol 1022.51
    n-decane 102.76
    butyronitrile 1777.1
    3,7-dimethyl-1-octanol 437.93
    1-chlorooctane 383.49
    1-chlorotetradecane 140.24
    n-nonane 100.29
    undecane 69.44
    tert-butylcyclohexane 181.28
    cyclooctane 160.82
    cyclopentanol 1679.07
    tetrahydropyran 3912.24
    tert-amyl methyl ether 1620.58
    2,5,8-trioxanonane 1320.82
    1-hexene 864.99
    2-isopropoxyethanol 1185.15
    2,2,2-trifluoroethanol 1301.01
    methyl butyrate 2543.73

    Scent© AI

1 4

IFRA standard 51

Recommendation
No restriction
Maximum acceptable concentrations in the finished product (%)
Category 1
Products applied to the lips
 No restriction Category 7A
Rinse-off products applied to the hair with some hand contact
 No restriction
Category 2
Products applied to the axillae
 No restriction Category 7B
Leave-on products applied to the hair with some hand contact
 No restriction
Category 3
Products applied to the face/body using fingertips
 No restriction Category 8
Products with significant anogenital exposure
 No restriction
Category 4
Products related to fine fragrance
 No restriction Category 9
Products with body and hand exposure, primarily rinse off
 No restriction
Category 5A
Body lotion products applied to the body using the hands (palms), primarily leave on
 No restriction Category 10A
Household care products with mostly hand contact
 No restriction
Category 5B
Face moisturizer products applied to the face using the hands (palms), primarily leave on
 No restriction Category 10B
Household care products with mostly hand contact, including aerosol/spray products (with potential leave-on skin contact)
 No restriction
Category 5C
Hand cream products applied to the hands using the hands (palms), primarily leave on
 No restriction Category 11A
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate without UV exposure
 No restriction
Category 5D
Baby Creams, baby Oils and baby talc
 No restriction Category 11B
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate with potential UV exposure
 No restriction
Category 6
Products with oral and lip exposure
 No restriction Category 12
Products not intended for direct skin contact, minimal or insignificant transfer to skin
 No restriction