STORAGE RECOMMENDATIONS
Store Santoweb D in single stacked pallets in a cool, dry, well ventilated area, avoiding exposure of the packaged
product to direct sunlight.  Double stacking of palletized material and/or exceeding 35°C can result in unusual
agglomeration of product.  Santoweb D fibers tend to absorb moisture that can be removed by exposure to
moderate heat, not to exceed 110°C.
PRODUCT INFORMATION
Santoweb D
Product form
PRODUCT SPECIFICATIONS
Appearance
Heat loss
Ash
Tensile strength in SBR/NR
Young's modulus in SBR/NR
Elongation in SBR/NR
Dispersion in SBR/NR
TYPICAL PROPERTIES
Density at 25°C
Bulk density
(%)
(%) max.
(psi) min.
(psi) min.
(%) max.
(bundles/in2) max.
(kg/m3)
(kg/m3)
Test method
FF97.5
FGr97.7
FGr90.9
FF97.11
FF97.11
FF97.11
FF97.11
Specialties
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Product Data
SANTOWEB D
Treated cellulose fibers
CAS Reg. No.: 65996-61-4
FUNCTION
Santoweb D, a treated cellulose fiber product, provides reinforcement for uncured and cured rubber
compounds, increases product stiffness and reduces cut growth rate in rubber compounds.
MAJOR APPLICATIONS AND PROPERTIES
- Santoweb D can be used for raw edge V-belt base compounds, low pressure hoses, gaskets,
diaphragms, and tire bead apex compounds.
- Santoweb D fiber increases stress of elongation and compression of NR, SBR, BR and CR
compounds.
- It should be used with a methylene donating chemical for applications in which adhesion of the
fiber to the rubber matrix is critical.
- Santoweb D increases green strength, reduces die swell and cold flow.
- Santoweb D discolors because it is black, but does not cause compound staining.
- Santoweb D is regulated for use in articles in contact with food as specified under BgVV XXI,
Category 4.  Santoweb D is not regulated for use in FDA food contact applications.
COMPOUNDING INFORMATION
Santoweb D provides improved green strength with loadings of 1-4 wt.%, increased flexural stress at
levels of 5-15 wt.% and very significant fiber reinforcement at 10-20 wt.%.  Since Santoweb D contains
resorcinol-formaldehyde resin, a methylene receptor, one should use a methylene donor chemical,
such as hexa(methoxymethyl)melamine (Resimene 3520), at a 1:25 hexa(methoxymethyl)melamine
(Resimene 3520) to Santoweb D ratio to maximize bonding of the fibers to the rubber matrix.  To
ensure good dispersion of the treated cellulose fiber product add it early in the mix cycle just as you
would add any reinforcing material.  And  when Santoweb D accounts for more than 10% of the
compound, reduce the mixer fill factor by 5-10% to ensure good mixing.  Add the methylene donor in
the end of a single mix cycle or in the second stage of a two stage mix as adding it earlier could cause
premature resin cross linking making further processing more difficult.  During processing steps, such
as calendering and extruding, fibers become oriented in the direction of flow.  Special designed
extruder dies can provide control over the direction of the fibers so that parts can have predominantly
longitudinal, radial, and/or circumferential orientation as needed for part design.  As an example a hose
made with fiber oriented in a circumferential direction will expand less when pressurized and have an
increased burst strength.