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Identification

Chemical structure
Display Name:
Silicic acid, lithium magnesium sodium salt
EC Number:
258-476-2
EC Name:
Silicic acid, lithium magnesium sodium salt
CAS Number:
53320-86-8
Molecular formula:
Na0.7+ [(Si8Mg5.5Li0.3) O20(OH)4]0.7-
IUPAC Name:
Silicic acid, lithium magnesium sodium salt

Type of Substance

Composition:
mono-constituent substance
Origin:
inorganic

Substance Identifiers open all close all

  • Laponite® (various grades other than that specified including but not restricted to D, G, RD, SH, XLG)
  • Laponite® CP (a now obsolete grade)
  • Optigel® (various grades)
  • Silikat S-33
  • Compositions

    Boundary Composition(s) open all close all

    State Form:
    solid: nanoform


    Constituent 1
    Chemical structure
    Reference substance name:
    Silicic acid, lithium magnesium sodium salt
    EC Number:
    258-476-2
    EC Name:
    Silicic acid, lithium magnesium sodium salt
    CAS Number:
    53320-86-8
    Molecular formula:
    Na0.7+ [(Si8Mg5.5Li0.3) O20(OH)4]0.7-
    IUPAC Name:
    Silicic acid, lithium magnesium sodium salt

    Characterisation of nanoforms

    Type of information reported:
    single nanoform

    Shape

    Shape description
    Shape category:
    platelet
    Shape:
    plate
    Pure shape:
    yes

    Particle size distribution and range

    Particle size distribution and range
    Shape category:
    platelet
    Percentileopen allclose all
    Percentile:
    D90
    Typical value:
    ca. 21 nm
    Range:
    > 12.6 - < 29.4 nm
    Percentile:
    D50
    Typical value:
    ca. 10.63 nm
    Range:
    > 6 - < 15 nm
    Percentile:
    D10
    Typical value:
    ca. 6 nm
    Range:
    > 3.6 - < 8.4 nm
    Range of length:
    > 0.9 - < 1 nm
    Range of lateral dimension 1:
    >= 4 - <= 73 nm
    Range of lateral dimension 2:
    >= 4 - <= 73 nm
    Typical aspect ratio (:1):
    ca. 25 :1
    Range of aspect ratio (:1):
    >= 4 - <= 73
    Additional information:

    LAPONITE Type 2 products are placed on the market in the form of a finely divided granular powder and also in the form of a ready-to-use concentrated dispersion in water.   The powder granules are composed of aggregates of nano-sized particles. The powder granules are micro-sized particles. Hence Laponite Type 2 is supplied to downstream users as a powder product with micro-sized particles. During use in most application fields the user will add LAPONITE Type 2 powderproduct intowaterwithmixing. The aggregates willwet out, hydrate anddisperseintoindividual primary particles, givinga clear, colourless and stable dispersion of nanoparticles, also called a colloidal dispersion. In some application fields, LAPONITE Type 2 powder is wetted out into non-aqueous fluids, such as mineral or silicone oils or polyols. In such cases LAPONITE Type 2 does not disperse into individual primary particles and a colloidal dispersion is not formed. The LAPONITE Type 2 products supplied as a ready-to-use concentrated dispersion in water are already in the form of a stable dispersion of nanoparticles.   Measurementsbyanalyticaltechniquessuchas AFM,TEM, SAXS and comparisons made with similar materials, naturally occurring layered silicates, hectorite and montmorillonite indicatethatLAPONITE Type 2primary particles havealayerstructure,and aredisc-shaped. According to the CommissionRecommendationof18October, 2011,onthedefinitionofnanomaterial (2011/696/EU), 100% of the synthetic silicate component of LAPONITE Type 2 is classified as a nanomaterial. Some grades of LAPONITE Type 2 contain additives; these are either water soluble salts or polymer materials, which are not nanomaterials.   Typical particlesizemeasurementsofLAPONITE Type 2materialsinthesetwodifferentphysicalstates,powderas supplied and dispersed colloid, are shown below:  

    Powder as supplied (D50)
    D10 = 4.6µm, D50 = 48.2µm, D90 = 124.3µm, D99 = 167.0µm(1) (1)Sympatec particle size analyser, Helos H0399, incorporating a Retsch Vibri feeder, Rodos and venturi(laser deflection on powder dispersed in air)  

    Dispersed colloid (Z Ave.)
    Z Ave. = 25.4nm(2) Typically, the disc shaped LAPONITE Type 2 primary particle is 0.9-1.0nm in thickness (x Dimension) and 4.0-73.0nm in diameter (y and z Dimensions)
    (2) Malvern Zetasizer Nano ZS (Dynamic Light Scattering – DLS – on 1% solids dispersion in deionized water)

    The dispersed particles have a negative charge on the surface and a positive charge on the edge of the disc. When LAPONITE Type 2 is dispersed in water and used in a formulation, such as a paint, drilling fluid or cosmetic product, the oppositely charged edges and faces form electrostatic associations with each other. The charged sections of the LAPONITE Type 2 discs can also form associations with oppositely charged sections of other particles, such as dispersion resins and pigments and also molecules, such as polymers that are present in the formulation. These associations form a single continuous network that extends throughout the whole of the container that is holding the formulation. It is this network of particle-particle and particle-polymer associations which develops the very high levels of viscous structure that is typical of formulations containing LAPONITE Type 2. These viscous structures are micro-sized. The viscous structure can be reduced under shear forces, such as mixing or pumping and will build up again when shear forces are removed.   Typical use levels of LAPONITE Type 2 in a formulation can range from 0.1% up to 5% or higher.
    Fraction of constituent particles in the size range 1-100 nm:
    >= 99 - < 100 %

    Crystallinity

    Structures
    Structure:
    crystalline
    Pure structure:
    yes
    Crystal system:
    other: smectite clay, mixture of octahedral and tetrahedral

    Specific surface area

    Range of specific surface area:
    >= 306 - <= 309 m²/g

    Surface functionalisation / treatment

    Surface treatment applied:
    no

    Legal Entity Composition(s) open all close all

    State Form:
    solid: nanoform


    Constituent 1
    Chemical structure
    Reference substance name:
    Silicic acid, lithium magnesium sodium salt
    EC Number:
    258-476-2
    EC Name:
    Silicic acid, lithium magnesium sodium salt
    CAS Number:
    53320-86-8
    Molecular formula:
    Na0.7+ [(Si8Mg5.5Li0.3) O20(OH)4]0.7-
    IUPAC Name:
    Silicic acid, lithium magnesium sodium salt

    Characterisation of nanoforms

    Type of information reported:
    single nanoform

    Shape

    Shape description
    Shape category:
    platelet
    Shape:
    plate
    Pure shape:
    yes

    Particle size distribution and range

    Particle size distribution and range
    Shape category:
    platelet
    Percentileopen allclose all
    Percentile:
    D90
    Typical value:
    ca. 21 nm
    Range:
    > 12.6 - < 29.4 nm
    Percentile:
    D50
    Typical value:
    ca. 10.63 nm
    Range:
    > 6 - < 15 nm
    Percentile:
    D10
    Typical value:
    ca. 6 nm
    Range:
    > 3.6 - < 8.4 nm
    Range of length:
    > 0.9 - < 1 nm
    Range of lateral dimension 1:
    >= 4 - <= 73 nm
    Range of lateral dimension 2:
    >= 4 - <= 73 nm
    Typical aspect ratio (:1):
    ca. 25 :1
    Range of aspect ratio (:1):
    >= 4 - <= 73
    Additional information:

    LAPONITE Type 2 products are placed on the market in the form of a finely divided granular powder and also in the form of a ready-to-use concentrated dispersion in water.   The powder granules are composed of aggregates of nano-sized particles. The powder granules are micro-sized particles. Hence Laponite Type 2 is supplied to downstream users as a powder product with micro-sized particles. During use in most application fields the user will add LAPONITE Type 2 powderproduct intowaterwithmixing. The aggregates willwet out, hydrate anddisperseintoindividual primary particles, givinga clear, colourless and stable dispersion of nanoparticles, also called a colloidal dispersion. In some application fields, LAPONITE Type 2 powder is wetted out into non-aqueous fluids, such as mineral or silicone oils or polyols. In such cases LAPONITE Type 2 does not disperse into individual primary particles and a colloidal dispersion is not formed. The LAPONITE Type 2 products supplied as a ready-to-use concentrated dispersion in water are already in the form of a stable dispersion of nanoparticles.   Measurementsbyanalyticaltechniquessuchas AFM,TEM, SAXS and comparisons made with similar materials, naturally occurring layered silicates, hectorite and montmorillonite indicatethatLAPONITE Type 2primary particles havealayerstructure,and aredisc-shaped. According to the CommissionRecommendationof18October, 2011,onthedefinitionofnanomaterial (2011/696/EU), 100% of the synthetic silicate component of LAPONITE Type 2 is classified as a nanomaterial. Some grades of LAPONITE Type 2 contain additives; these are either water soluble salts or polymer materials, which are not nanomaterials.   Typical particlesizemeasurementsofLAPONITE Type 2materialsinthesetwodifferentphysicalstates,powderas supplied and dispersed colloid, are shown below:  

    Powder as supplied (D50)
    D10 = 4.6µm, D50 = 48.2µm, D90 = 124.3µm, D99 = 167.0µm(1) (1)Sympatec particle size analyser, Helos H0399, incorporating a Retsch Vibri feeder, Rodos and venturi(laser deflection on powder dispersed in air)  

    Dispersed colloid (Z Ave.)
    Z Ave. = 25.4nm(2) Typically, the disc shaped LAPONITE Type 2 primary particle is 0.9-1.0nm in thickness (x Dimension) and 4.0-73.0nm in diameter (y and z Dimensions)
    (2) Malvern Zetasizer Nano ZS (Dynamic Light Scattering – DLS – on 1% solids dispersion in deionized water)

    The dispersed particles have a negative charge on the surface and a positive charge on the edge of the disc. When LAPONITE Type 2 is dispersed in water and used in a formulation, such as a paint, drilling fluid or cosmetic product, the oppositely charged edges and faces form electrostatic associations with each other. The charged sections of the LAPONITE Type 2 discs can also form associations with oppositely charged sections of other particles, such as dispersion resins and pigments and also molecules, such as polymers that are present in the formulation. These associations form a single continuous network that extends throughout the whole of the container that is holding the formulation. It is this network of particle-particle and particle-polymer associations which develops the very high levels of viscous structure that is typical of formulations containing LAPONITE Type 2. These viscous structures are micro-sized. The viscous structure can be reduced under shear forces, such as mixing or pumping and will build up again when shear forces are removed.   Typical use levels of LAPONITE Type 2 in a formulation can range from 0.1% up to 5% or higher.
    Fraction of constituent particles in the size range 1-100 nm:
    >= 99 - < 100 %

    Crystallinity

    Structures
    Structure:
    crystalline
    Pure structure:
    yes
    Crystal system:
    other: smectite clay, mixture of octahedral and tetrahedral

    Specific surface area

    Range of specific surface area:
    >= 306 - <= 309 m²/g

    Surface functionalisation / treatment

    Surface treatment applied:
    no
    State Form:
    solid: particulate/powder


    Constituent 1
    Chemical structure
    Reference substance name:
    Silicic acid, lithium magnesium sodium salt
    EC Number:
    258-476-2
    EC Name:
    Silicic acid, lithium magnesium sodium salt
    CAS Number:
    53320-86-8
    Molecular formula:
    Na0.7+ [(Si8Mg5.5Li0.3) O20(OH)4]0.7-
    IUPAC Name:
    Silicic acid, lithium magnesium sodium salt
    State Form:
    solid: nanoform


    Constituent 1
    Chemical structure
    Reference substance name:
    Silicic acid, lithium magnesium sodium salt
    EC Number:
    258-476-2
    EC Name:
    Silicic acid, lithium magnesium sodium salt
    CAS Number:
    53320-86-8
    Molecular formula:
    Na0.7+ [(Si8Mg5.5Li0.3) O20(OH)4]0.7-
    IUPAC Name:
    Silicic acid, lithium magnesium sodium salt

    Characterisation of nanoforms

    Particle size distribution and range

    Particle size distribution and range
    Range of length:
    ca. 62.861 nm
    Range of lateral dimension 1:
    ca. 62.861 nm
    Range of lateral dimension 2:
    ca. 62.861 nm

    Specific surface area

    Range of specific surface area:
    ca. 353.433 m²/g

    Composition(s) generated upon use

    Other types of composition(s)