Rubber Business Group
Technical Rubber Chemicals
Information
TITLE:
Vulkacit NZ Product Information
Sulphenamide accelerator
TEXT:
Chemical Composition
N-tert.-butyl-benzothiazolesulfenamide
N CH3
S N CH3
H
S CH3
Molecular weight: 238
International abbreviation: TBBS
Product Description
®
Supply form: Vulkacit NZ/EG beige granules
Assay (%): minimum 97
Initial melting point (°C): 1.3
Discoloration: slight yellowing when exposed to light
These raw material properties are typical properties and, unless specifically
indicated otherwise, are not to be considered as delivery specification.
Application Vulkacit NZ is a sulphenamide accelerator with a
delayed onset of cure between Vulkacit CZ (CBS) and
MOZ (MBS), yielding higher moduli than both of the
latter products. It is suitable for rubber goods subjected
to high dynamic stresses and can be employed for NR,
IR, BR, SBR and NBR.
Technical Information
KA-KCH-0117e/01/11.97
Page 1 of 4
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Vulkacit NZ can be employed for compression,
injection and transfer molding and is also applicable in
curing processes, such as steam, fluid bed, microwave
and LCM, but not in hot-air curing, because it delays
the onset of cure too much.
Areas of application include tyres, conveyor belts,
shock absorbers, mountings, seals, hose, profiles,
sleeves, cable, footwear and other rubber goods.
Processing Vulkacit NZ has good dispersion characteristics in
rubber compounds. Addition at the end of the mixing
cycle or in a second banbury pass is recommended,
exposure to temperatures of 120 °C or above for any
length of time should be avoided. Compounded stocks
have very good storage stability.
The use of zinc oxide is necessary and stearic acid
should be included where high modulus values are
®
required. Zinkoxyd aktiv exhibits the unusual
characteristic of further improving scorch resistance
while hardly affecting the total curing time.
Vulkacit NZ offers very favourable flow cure time
ratios, a good plateau and a high degree of
crosslinking. It is particularly suitable in „low sulfur
cures“ providing good resistance to ageing.
Most suitable secondary accelerators are
dithiocarbamates (Vulkacit ZBEC or LDA), thiurams
®
(Rhenocure Thiuram MS) and thioureas (ETU). Basic
substances, such as Vulkacit D or magnesium oxide
are less efficient activators for sulphenamides.
®
Vulkalent G, Vulkalent E or organic acids may be
employed as retarders.
Technical Information
KA-KCH-0117e/01/11.97
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Rubber Business Group
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Typical levels of addition based on 100 parts by weight
of elastomer are:
®
Application Vulkacit NZ Additional Accelerator Sulphur
(phr)
(phr) (phr)
NR:
Tyre Treads a) 0.5 - 0.8 2.2 - 2.7
®
b) 0.3 0.4 Vulkacit Merkapto or 2.2 - 2.7
DM
®
Tyre carcass and a) 0.6 - 0.9 0 - 0.3 Vulkacit D 2.2 - 2.5
breakers
®
Conveyor belts a) 0.6 - 0.8 0 - 0.25 Vulkacit Merkapto 2.2 - 2.5
®
Mechanical goods a) 0.4 - 0.9 0.2 - 0.3 Vulkacit DM or 2.0 - 2.5
Merkapto
®
b) 1.2 - 2.5 0.2 - 0.5 Vulkacit Thiuram 0.5 - 1.0
SBR:
®
Tyre treads a) 1.0 - 1.4 0 - 0.2 Rhenocure Thiuram MS 1.6 - 2.1
®
Conveyor belts a) 1.1 - 1.4 0 - 0.2 Rhenocure Thiuram MS 1.6 - 2.0
®
Mechanical goods a) 1.0 - 1.6 0 - 0.8 Vulkacit D or 1.0 - 2.5
®
0 - 0.6 Rhenocure Thiuram MS
®
b) 1.0 - 3.0 0.2 - 0.7 Vulkacit Thiuram 0.5 - 1.0
NBR:
®
Mechanical goods a) 1.0 - 1.5 0 - 0.4 Vulkacit D or 1.5 - 2.4
®
0 - 0.2 Rhenocure Thiuram MS
®
b) 2.0 - 3.5 0 - 1.5 Rhenogran ETU or 0.5 - 1.0
®
Rhenocure CA
Vulcanisate Properties Vulkacit NZ imparts a bitter taste and a slight amine-
type odour to rubber articles. It does not bloom when
used at recommended levels, but may cause a slight
yellowing on white goods, especially when exposed to
light.
In regular sulphur cures, Vulkacit NZ produces very
good tensile strength, good rebound resilience and
good flex-cracking properties. In „low sulphur cures“ it
combines good compression set at elevated
temperatures with very good resistance to ageing.
Secondary accelerators improve modulus and
resilience slightly.
Solubility Vulkacit NZ is soluble in aliphatic hydrocarbons,
toluene, methylene chloride, ethyl acetate, acetone
Technical Information
KA-KCH-0117e/01/11.97 and ethanol, but insoluble in water.
Page 3 of 4
Rubber Business Group
Technical Rubber Chemicals
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Storage Vulkacit NZ should be stored in closed original
packaging under cool (approximately 25 °C) and dry
conditions. Storage stability under recommended
conditions is one year.
Health and Safety See EU safety data sheet 079778
Registered Trademarks of Bayer AG:
Vulkacit
Vulkalent
Zinkoxyd aktiv
Registered Trademarks of Rhein Chemie Rheinau GmbH:
Rhenocure
Rhenogran
Author(s):
RUZ
This information and our technical advice - whether verbal, in writing or by way of trials - are given in good faith but without warranty, and this also applies
where proprietary rights of third parties are involved. Our advice does not release you from the obligation to check its validity and to test our products as
to their suitability for the intended processes and uses. The application, use and processing of our products and the products manufactured by you on
the basis of our technical advice are beyond our control and, therefore, entirely your own responsibility. Our products are sold in accordance with the
current version of our General Conditions of Sale and Delivery.
__________________________________________________________________________________________________________________________
Technical Information Bayer AG, D-51368 Leverkusen
KA-KCH-0117e/01/11.97 Rubber Business Group
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