1,1,1,5,5,5-Hexamethyl-3-phenyl-3-(trimethylsilyloxy)trisiloxane

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  • Identifiers

    CAS number
    2116-84-9

    Molecular formula
    C15H32O3Si4

    SMILES
    C[Si](C)(C)O[Si](C1=CC=CC=C1)(O[Si](C)(C)C)O[Si](C)(C)C

    Safety labels

    Acute Toxic
    Acute Toxic

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Green 41.39%
    Floral 35.07%
    Mint 30.6%
    Woody 27.34%
    Fruity 26.92%
    Fresh 26.6%
    Odorless 25.55%
    Cooling 25.13%
    Herbal 25.02%
    Camphoreous 23.03%

     

    Flavor
    Green 35.74%
    Bitter 34.14%
    Mild 25.73%
    Fruity 23.83%
    Sweet 22.23%
    Herbal 21.53%
    Earthy 21.47%
    Citrus 21.05%
    Rose acetate 19.98%
    Old wood 19.82%

     

    Odor impact est.
    Low

  • Properties

    pKa est.
    8.72 (weak base)

    Molecular weight
    372.75 g/mol

    Flash point

    • 107.73 ˚C est.

  • Synonyms

    • 1,1,1,5,5,5-Hexamethyl-3-phenyl-3-(trimethylsilyloxy)trisiloxane
    • DTXSID6051857
    • RefChem:1051654
    • DTXCID9030414
    • 2116-84-9
    • Phenyltris(trimethylsiloxy)silane
    • 1,1,1,5,5,5-hexamethyl-3-phenyl-3-((trimethylsilyl)oxy)trisiloxane
    • Tris(trimethylsiloxy)phenylsilane
    • trimethyl-[phenyl-bis(trimethylsilyloxy)silyl]oxysilane
    • MFCD00053665
    • C15H32O3Si4
    • S3QI0ZXT5X
    • Phenyltris(trimethylsiloxyl)silane
    • s21150
    • 1,1,1,5,5,5-hexamethyl-3-phenyl-3-[(trimethylsilyl)oxy]trisiloxane
    • Trisiloxane, 1,1,1,5,5,5-hexamethyl-3-phenyl-3-((trimethylsilyl)oxy)-
    • Dow Corning 556
    • Silicone DC 556
    • Phenyl trimethyl siloxane
    • UNII-S3QI0ZXT5X
    • 556 Phenyl Trimethicone
    • SCHEMBL339880
    • trimethyl-[phenyl-bis(trimethylsilyloxy)silyl]oxy-silane
    • phenyl tris(trimethylsiloxy)silane
    • LINXHFKHZLOLEI-UHFFFAOYSA-N
    • Phenyltris(trimethylsilyloxy)silane
    • EINECS 218-320-6
    • DC 556
    • AKOS025310938
    • AS-15561
    • SY057388
    • DB-045505
    • M3T(Ph): tris(trimethylsiloxy)phenylsilane
    • CS-0186280
    • H1460
    • NS00044920
    • D91036
    • Q27288541
    • 1,1,5,5,5-Hexamethyl-3-phenyl-3-((trimethylsilyl)oxy)trisiloxane
    • 2116-84-9

  • Applications

    For 1,1,1,5,5,5-Hexamethyl-3-phenyl-3-(trimethylsilyloxy)trisiloxane (CAS 2116-84-9), this compound primarily serves as an intermediate in silicone chemistry, commonly used as a precursor to functionalized siloxanes and as a crosslinking or chain-terminating reagent to tailor cure behavior, hydrophobicity, and thermal stability of silicone polymers and elastomers. It can act as a surface-modifying and adhesion-promoting reagent in coatings, inks, and sealants, enabling improved bonding to inorganic substrates such as glass, metal, and ceramics. In specialty polymer and elastomer development, it provides a route to tailored siloxane architectures with enhanced performance. In electronics and optics formulations, it may be employed to tune dielectric properties and moisture resistance of silicone-based encapsulants and coatings. Its functional groups also allow it to be used as a siloxane coupling agent precursor for inorganic–organic interfaces, subject to formulation limits and local regulations.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 315.3
    methanol 234.76
    isopropanol 330.85
    water 5.61
    ethyl acetate 300.2
    n-propanol 364.75
    acetone 510.79
    n-butanol 335.7
    acetonitrile 183.46
    DMF 885.88
    toluene 370.92
    isobutanol 300.18
    1,4-dioxane 489.98
    methyl acetate 298.69
    THF 1552.99
    2-butanone 464.61
    n-pentanol 310.09
    sec-butanol 381.79
    n-hexane 182.39
    ethylene glycol 99.37
    NMP 1157.07
    cyclohexane 295.78
    DMSO 793.31
    n-butyl acetate 379.93
    n-octanol 361.84
    chloroform 1154.36
    n-propyl acetate 317.33
    acetic acid 294.68
    dichloromethane 831.26
    cyclohexanone 864.33
    propylene glycol 266.5
    isopropyl acetate 275.47
    DMAc 720.36
    2-ethoxyethanol 283.36
    isopentanol 268.66
    n-heptane 180.18
    ethyl formate 264.66
    1,2-dichloroethane 502.78
    n-hexanol 407.36
    2-methoxyethanol 416.19
    isobutyl acetate 275.06
    tetrachloromethane 197.82
    n-pentyl acetate 408.13
    transcutol 384.39
    n-heptanol 330.35
    ethylbenzene 254.71
    MIBK 298.05
    2-propoxyethanol 466.04
    tert-butanol 354.6
    MTBE 266.92
    2-butoxyethanol 387.14
    propionic acid 334.91
    o-xylene 233.94
    formic acid 98.78
    diethyl ether 287.19
    m-xylene 261.23
    p-xylene 317.63
    chlorobenzene 456.93
    dimethyl carbonate 221.56
    n-octane 110.89
    formamide 164.5
    cyclopentanone 1267.8
    2-pentanone 423.26
    anisole 371.07
    cyclopentyl methyl ether 651.03
    gamma-butyrolactone 1145.85
    1-methoxy-2-propanol 467.4
    pyridine 669.5
    3-pentanone 331.64
    furfural 854.27
    n-dodecane 83.93
    diethylene glycol 258.41
    diisopropyl ether 149.71
    tert-amyl alcohol 349.6
    acetylacetone 456.93
    n-hexadecane 90.84
    acetophenone 400.22
    methyl propionate 346.31
    isopentyl acetate 330.4
    trichloroethylene 906.38
    n-nonanol 338.43
    cyclohexanol 492.47
    benzyl alcohol 337.47
    2-ethylhexanol 284.42
    isooctanol 265.03
    dipropyl ether 350.08
    1,2-dichlorobenzene 384.79
    ethyl lactate 254.47
    propylene carbonate 704.45
    n-methylformamide 366.1
    2-pentanol 302.26
    n-pentane 167.12
    1-propoxy-2-propanol 453.2
    1-methoxy-2-propyl acetate 372.38
    2-(2-methoxypropoxy) propanol 297.73
    mesitylene 181.08
    ε-caprolactone 700.86
    p-cymene 189.88
    epichlorohydrin 884.53
    1,1,1-trichloroethane 465.41
    2-aminoethanol 214.74
    morpholine-4-carbaldehyde 747.04
    sulfolane 1543.09
    2,2,4-trimethylpentane 74.36
    2-methyltetrahydrofuran 825.59
    n-hexyl acetate 503.35
    isooctane 65.83
    2-(2-butoxyethoxy)ethanol 393.83
    sec-butyl acetate 244.67
    tert-butyl acetate 291.44
    decalin 132.32
    glycerin 272.63
    diglyme 516.74
    acrylic acid 297.14
    isopropyl myristate 252.32
    n-butyric acid 406.37
    acetyl acetate 226.49
    di(2-ethylhexyl) phthalate 247.9
    ethyl propionate 289.89
    nitromethane 387.58
    1,2-diethoxyethane 269.42
    benzonitrile 374.69
    trioctyl phosphate 224.33
    1-bromopropane 437.24
    gamma-valerolactone 1138.14
    n-decanol 266.71
    triethyl phosphate 195.6
    4-methyl-2-pentanol 211.23
    propionitrile 246.74
    vinylene carbonate 561.23
    1,1,2-trichlorotrifluoroethane 641.5
    DMS 302.5
    cumene 179.5
    2-octanol 302.99
    2-hexanone 383.38
    octyl acetate 331.96
    limonene 273.14
    1,2-dimethoxyethane 463.61
    ethyl orthosilicate 189.44
    tributyl phosphate 226.91
    diacetone alcohol 359.5
    N,N-dimethylaniline 325.01
    acrylonitrile 279.16
    aniline 367.01
    1,3-propanediol 250.03
    bromobenzene 474.58
    dibromomethane 693.52
    1,1,2,2-tetrachloroethane 902.97
    2-methyl-cyclohexyl acetate 379.2
    tetrabutyl urea 334.42
    diisobutyl methanol 187.66
    2-phenylethanol 361.96
    styrene 289.98
    dioctyl adipate 325.13
    dimethyl sulfate 360.72
    ethyl butyrate 322.52
    methyl lactate 310.13
    butyl lactate 386.82
    diethyl carbonate 211.11
    propanediol butyl ether 403.78
    triethyl orthoformate 270.08
    p-tert-butyltoluene 203.51
    methyl 4-tert-butylbenzoate 401.57
    morpholine 666.92
    tert-butylamine 276.9
    n-dodecanol 213.1
    dimethoxymethane 475.84
    ethylene carbonate 458.98
    cyrene 472.99
    2-ethoxyethyl acetate 330.98
    2-ethylhexyl acetate 301.85
    1,2,4-trichlorobenzene 478.36
    4-methylpyridine 611.36
    dibutyl ether 316.57
    2,6-dimethyl-4-heptanol 187.66
    DEF 430.1
    dimethyl isosorbide 579.56
    tetrachloroethylene 496.98
    eugenol 406.6
    triacetin 379.55
    span 80 480.09
    1,4-butanediol 152.3
    1,1-dichloroethane 506.4
    2-methyl-1-pentanol 260.4
    methyl formate 298.5
    2-methyl-1-butanol 285.02
    n-decane 133.83
    butyronitrile 279.95
    3,7-dimethyl-1-octanol 267.46
    1-chlorooctane 305.32
    1-chlorotetradecane 152.07
    n-nonane 135.23
    undecane 101.24
    tert-butylcyclohexane 116.39
    cyclooctane 136.77
    cyclopentanol 681.33
    tetrahydropyran 785.41
    tert-amyl methyl ether 254.47
    2,5,8-trioxanonane 409.65
    1-hexene 329.2
    2-isopropoxyethanol 240.6
    2,2,2-trifluoroethanol 138.97
    methyl butyrate 379.35

    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