Latent Hardeners and Accelerators for Epoxy Resin

AJICURE TM

AJICURE is a trade mark of latent hardener and accelerator for one-component epoxy resin system.
While various types of AJICURE have been developed, AJICURE PN-23 and MY-24 are popularly used for multi-functional one-component epoxy resin as hardeners and accelerators which might rapidly cure the resin at a low temperature and have a longer pot life.

Features of AJICURE PN-23 and MY-24

Characteristics

  • Fine particles may disperse easily in epoxy resin
  • High safety
  • High reactivity, making the resin possible to cure at 80ºC
  • High storage stability and longer pot life
  • Superior heat and water resistance of applied materials

    • Application areas

  • Electronic components and parts
  • Civil engineering and construction
  • Automobiles
  • Composite materials

    • Practical uses

  • Glue, insulating seal, cast molding for electric/
  • electronic parts
  • Powder paints
  • Adhesive for construction
  • Prepreg products

    • Physical properties

      AJICURE PN-23 AJICURE MY-24
    Appearance Pale yellow powder Pale brown powder
    Specific gravity
    		 1.21 1.21
    Melting point (ºC) 105 120
    Particle size 10μm at average 10μm at average
    *
    Mixture properties* Cure temp.
    		 80ºC 100ºC
    Cure time 30 min. 1 hr
    Pot life 1 month/40ºC 3 months/40ºC
    Tg (ºC) 140 100
    Heat generated by curing Higher Lower
    Tensile shear strength 140 Kgf/cm2 240 Kgf/cm2
    Appearance of cured product Brown w/o luster Pale yellow,clear with luster

    * of mixture with liquid Bisphenol A epoxy resin

    AJICURE application as hardeners

    AJICURE PN-23 is characterized by rapid cure, and AJICURE MY-24 by superior physical property of cured product. By using the both of AJICURE PN-23 and MY-24, it is possible to expand the application of one-component epoxy resin.

    1. Curing at a low temperature (80 ~ 100ºC) for a short time (30 ~ 60 min.)
    2. Superior storage stability: pot life is more than 60 days at 40ºC
    3. Dosage should be determined (10 ~ 40 phr) depending on curing condition

    No. 1 2 3 4 5 6
    EP-828 100 100 100 100 100 100
    AJICURE PN-23 25 20 15 10 5 0
    AJICURE MY-24 0 5 10 15 20 25
    Aerosil #200 1 1 1 1 1 1
    *
    Initial viscosity (P/25ºC) 380 440 440 480 500 500
    *
    Pot life at 40ºC (day(s)) > 60 > 60 > 60 > 90 > 90 > 90
    Gel time (min.) 80ºC
    		15.6 17.2 20.0 22.9 38.8 54.9
      100ºC
    		3.6 3.7 3.9 3.9 4.2 4.3
      120ºC
    		1.9 2.1 2.4 2.8 4.1 6.4
    *
    Tg (ºC) [120ºC-0.5 hr] 139 133 116 109 89 83
    Shear bond strength [100ºC-1 hr]
    		123 121 135 144 168 234
    (kgf/cm2) [120ºC-1 hr]
    		135 143 150 174 207 235
    *
    Tensile strength (kgf/cm2) 471 464 491 473 540 505
    Elongation (%) 4.8 4.1 5.2 4.9 5.9 5.2
    *
    Absorbency (w %) 0.43 0.43 0.43 0.39 0.42 0.45
    Boiled water/1 hr [100ºC-1 hr]



    The more PN-23, the more rapid curing

    *

    Graph 1: Correlation between gel time and mix ratio

    The more MY-24,the more adhesive

    *

    Graph 2: Correlation between shear bond strength and mix ratio

    AJICURE application as accelerators

    Acceleration of curing DICY

    AJICURE PN-23 and MY-24 can be superior latent accelerators for dicyandiamide (DICY). In comparison to urea accelerators and imidazole compounds,AJICURE PN-23 and MY-24 can produce one-component epoxy resin with a longer pot life which can be rapidly cured.

    No. 1 2 3 4 Control
    EP-828 100 100 100 100 100
    DICY 8 8 8 8 8
    AJICURE PN-23 1 3 5 - -
    AJICURE MY-24 - - - 5 -
    DCMU*1 - - - - 5
    *
    Pot life at 40ºC (day(s)) > 30 > 30 > 30 > 30 7
    *
    Gel time (min.) 100ºC
    		- - 27.7 50.5 67.8
      120ºC
    		42.7 13.9 7.4 10.7 18.4
    *
    Tg (ºC) [120ºC-1 hr] 141 137 139 141 139
    *
    Shear bond strength [120ºC-1 hr]
    		50 183 185 173 207
    (kgf/cm2) [150ºC-1 hr]
    		283 245 182 234 233

    *1 3-(3,4-dichlorophenyl)-1,1-dimethylurea

    Acceleration of curing MTHPA

    AJICURE MY-24 can be superior latent accelerators for methyl tetra hydro phthalic anhydride (MTHPA),
    by which one-component epoxy resin with a longer pot life can be produced.

    No. 1 2 3 Control
    EP-828 100 100 100 100
    MHHPA*1 85 85 - 85
    MTHPA*2 - - 80 -
    AJICURE MY-24 3 5 3 -
    DMP-30 - - - 1
    *
    Initial viscosity (P/25ºC) 7.2 8.0 7.0 6.0
    *
    Gel time (min.) 100ºC
    		25.3 16.1 35.1 12.9
      120ºC
    		8.0 5.7 9.7 5.0
    *
    Pot life at 40ºC (day(s)) 20 14 > 30 1
    *
    Tg (ºC) [120ºC-1 hr] 113 117 100 129
    [100ºC-0.5 hr + 150ºC-0.5 hr] 117 120 108 127
    *
    Electric property [120ºC-2 hrs]        
    Surface resistance (Ω) 2.4x1016 3.4x1016 1.5x1016 1.4x1017
    Volume resistance (Ω・cm) 1.8x1017 5.2x1016 4.1x1016 6.6x1016
    Permittivity 3.17 3.26 3.11 3.23
    Dielectric tangent (%) 0.6 0.6 0.6 0.5
    *
    Absorbency (w %) 0.3 0.3 0.3 0.3
    Boiled water/1 hr [120ºC-1 hr]

    *1 Methyl hexahydrophthalic anhydride *2 Methyl tetrahydrophthalic anhydride



    Correlation between dosage,gelling time and shear bond
    strength of PN-23

    *

    Hardness and storage stability of AJICURE PN series
    (mixing with Bisphenol F epoxy resin)

    *

    Correlation between dosage,gelling time,
    and shear bond strength of MY-24

    *

    Hardness and storage stability of AJICURE PN series
    (mixing with Bisphenol A epoxy resin)

    *

    Precautions in using AJICURE

    Safety data of AJICURE
    1. It is recommended to mix AJICURE with resin by a vacuum mixer in order to avoid absorbing moisture which may reduce storage stability.
    2. It is preferable not to use a kneading roller since kneading the mixture with rollers may affect the storage stability. In case of no choice but using a kneading roller, AJICURE should be added to the mixture at the end to minimize the effect to shear strength.
    3. It is necessary to carefully use such additives as solvent and diluent since they may affect the storage stability of mixture. They should be added to the mixture at the end to minimize the effect.
    4. Hardener may be separated when heating depending on the type of resin to be mixed. In such case, adding fine powder of silica might be effective.
    5. Curing should be in progress once started reaction even at a normal temperature. This is an advantageous property in case of filling the requirement for short-time curing.
    Note: Numerical values in this catalogue are representative values but not standard values of the product.
    Test items / Type AJICURE PN-23 AJICURE MY-24
    Acute oral toxicity LD50 (mouse)
    		 > 2.0 g
    		 > 2.0 g
    Primary dermal irritation (rabbit)
    		 Slight irritative
    		 Slight irritative
    Biodegradability
    		 None
    		 None
    Biologic concentration(carp) None None
    Further detail Technical information will be provided upon your request.