
Polymer Additives, a business unit within Sasol Wax, manufactures and
supplies innovative and unique products based on Fischer-Tropsch hydrocarbons
as well as paraffin and microcrystalline waxes to polymer producers and
converters in the moulding, extrusion, compounding and thermoforming industries.
The Fischer-Tropsch products marketed into the polymer industry are crystalline
linear, unsaturated hydrocarbons, or derivatives thereof, which are highly
compatible with polyolefins and which can be used as external lubricants
in polymers such as PVC.
The paraffin and microcrystalline waxes are low softening-temperature
petroleum based waxes. The branched-chain Microcrystalline waxes are particularly
effective in PVC systems.
PVC
Processing
The processing of rigid PVC requires conditions of high shear, temperature
and pressure. Under such conditions, the inherent thermal instability
of PVC leads to the degradation of the polymer via a mechanism of chain
scission i.e. HCl gas formation. Wax based lubricants are therefore required
to reduce/control shear conditions and promote flow whilst at the same
time control friction and ultimately the fusion properties of the formulation.
By virtue of their highly crystalline structure and linearity, the Sasolwax
range of PVC external lubricants have been proven in practice to be extremely
efficient when correctly formulated with internal lubricants hence allowing
optimal processing and physical properties to be achieved.
Polyolefin
Conversion
EnHance is a highly crystalline Fischer-Tropsch hydrocarbon designed to
improve the processability of polyolefins during injection moulding, extrusion,
compounding & extrusion blow moulding. Fischer-Tropsch hydrocarbons
are highly compatible with polyolefins and at the recommended loadings
are dissolved in the polymer matrix. EnHance essentially functions by
the mechanism of flow improvement thereby affording the converter the
opportunity to improve productivity, efficiency & quality through
machine optimization. The AdSperse range of Fischer-Tropsch hydrocarbons has been developed
specifically for use as dispersing aids in the manufacture of polyolefin
masterbatches and colour concentrates. Fischer-Tropsch hydrocarbons are
highly compatible with polyolefins.
The
Function of Dispersing Aids in Colour Masterbatches
Dispersion involves the breaking up of pigment agglomerates into
primary particles/crystals by shear forces. Pigments only develop their
full colour potential when the agglomerate form, in which they are supplied,
is broken down into a more uniform state consisting of primary particles/crystals.
Dispersing aids are used to wet the pigments, to penetrate the small hollows
between agglomerated particles and to facilitate the shear-related breakdown
of the solid, hard agglomerates. Even after breaking down the agglomerate,
the attractive forces between the primary particles/crystals may lead
to reagglomeration. Dispersing agents are also used to stabilise the dispersed
pigment particles to prevent reagglomeration in the polymer melt.
Contact Details
Sasol Wax: Polymer Additives
Tel: +27(0)11 873 7583
Fax: +27(0) 11 522 3423
Email: aldo.benetti@sasol.com
Website: www.sasolwax.com