JEC COMPOSITES MAGAZINE - Issue #87 - March 2014 Special JEC Europe - 80

sustainability
Consortium. Other cobalt salts (including
cobalt chloride and cobalt diacetate) were
already reclassified as CMR 1B in 2011.
More recently, in September 2013, the
US-based NTP released a report on the
testing of cobalt metal powder, indicating
carcinogenic effects on rats [1]. As a consequence the cobalt metal will be classified as
CMR 1B.
DSM has been working on the development of cobalt-free resin curing systems
for many years. The company successfully
scaled up the technology and filed a broad
range of patents covering many types of
accelerator systems and materials.
In 2012, DSM and AkzoNobel announced
the introduction of the BluCure™ brand.
The BluCure brand and seal stand for 100%
cobalt-free and true sustainability. BluCure™
products are either cobalt-free accelerators
or pre-accelerated resins that are 100%
cobalt-free, easy to use in composite manufacturing processes, and not labelled as
mutagenic, carcinogenic or toxic to human
beings. Following the launch of BluCure™,
DSM has introduced to the market numerous new cobalt-free pre-accelerated resins
based on this technology.
In terms of overall mechanical, thermal, and
chemical resistance properties, cobalt-free
composite components based on BluCure™
technology have similar performance
characteristics to their cobalt-containing
equivalents. For some accelerators and
resins, it has been found that the new
systems can even give a better cure than the
cobalt-containing reference, resulting in a
faster build-up of hardness and reduction
of residual styrene in the end-product. In
some applications, this may eliminate the
need for post-cure.
BluCure™ is the first cobalt-free curing
technology in the world for ambient
temperature cure. Through sub-licensing,
it is immediately and easily accessible to all
composite component and resin manufacturers around the world. Compared to
cobalt-containing alternatives (like cobalt
alkyds), it provides peace of mind on a truly
sustainable business operation also in the
future.

Alternatives to styrene
In unsaturated polyester and vinyl ester

resin systems, the predominantly used
reactive diluent is styrene. In Europe,
discussions on carcinogenicity concluded in
2007 that styrene is not classified for human
carcinogenicity. It has been demonstrated
that workers can safely work with styrene
under specific conditions. This involves
using the correct operational conditions as
well the right protective equipment in order
not to exceed exposure limits.
Meanwhile, in December 2012, the
European Committee for Risk Assessment
(RAC) adopted 15 opinions for harmonized classification and labelling (CLH),
including one for styrene monomer [2]. The
RAC agreed to classify styrene as "causing
damage to the hearing organs through prolonged or repeated exposure via inhalation,"
and as "a substance suspected of damaging
the unborn child (Reprotox 2)." The final
decision for proposals for harmonised classification and labelling, and other proposals,
will be taken by the European Commission
through a committee procedure.
In June 2011, the US Department of Health
listed styrene as a "reasonably anticipated
human carcinogenic," based on an assessment of publicly availability toxicity data
[3, 4]. So far this has not (yet) resulted in a
legal binding change of the classification or
a change to worker's exposure limits.
The composite industry has been minimising styrene emissions by using resins with
additives that reduce styrene evaporation,
using resins with a low styrene content,
and taking care of air quality in the working
environment (e.g. by using air ventilation
systems). Resins with a reduced content of
styrene can provide a temporary relief, and
they will help reduce styrene emissions to
some extent. Meanwhile, it is fair to say that
the listing in the US is still a very important
milestone towards creating an environment
where hazardous substances will be less
tolerated, and where more efforts will need
to be done to develop cleaner, more sustainable materials.
DSM is offering a broad range of styrenefree resins under the Atlac® Premium brand,
including systems for relining, pultrusion,
SMC/BMC, filament winding and open
mould processing techniques.
In addition, the styrene-free Palatal® resins
for chemical anchoring applications are

80 jec composites magazine / No87 March 2014

well known to the market. More recently,
the company launched styrene-free Daron®
resins for making high strength/high stiffness laminates with carbon fibres (which
contributed to the recent success of the
Nuna7 in the World Solar Challenge).
In 2013, DSM also introduced Beyone™
201-A-01, a resin that is styrene-free, cobaltfree (based on BluCure™ technology), and
is 40% bio-based. This resin is a key constituent of the new-to-the-world composite
system evaluated by Siemens Wind Power
for its next generation wind turbine blades,
offering easy resin infusion and processing,
zero styrene emissions, and excellent fibre/
resin interaction yielding superior strength
and fatigue resistance.

Conclusion
DSM believes that its continued success
will be driven by its ability to create shared
value for all stakeholders, now and in the
future. The company creates sustainable
shared value by innovating in ways that
allow its customers and other stakeholders
downstream in the value chain to provide
better people, planet and profit solutions -
solutions to the challenges facing society,
the environment and end-users. n
More information:
www.dsmcompositeresins.com
Contacts:
bert.handels@dsm.com,
willem.posthumus@dsm.com,
dragos.popescu@dsm.com
References:
[1] TR-581 Cobalt metal,
http://ntp.niehs.nih.
gov/?objectid=ABD1DF87-A7F0-5D9B0C6BA115E3117F5B
[2] RAC Opinion proposing harmonised
CLP for Styrene, http://echa.europa.eu/
documents/10162/d96caf76-f7fe-40cb-acd17859a4d3071d
[3] Chemical & Engineering News, vol. 89,
no. 25, page 11, eds. W.G. Schulz, S.L. Cai,
http://www.cen-online.org)
[4] 12th report on Carcinogens (2011), http://ntp.niehs.nih.
gov/?objectid=03C9AF75-E1BF-FF40-DBA9EC0928DF8B15, http://ntp.niehs.nih.gov/
ntp/roc/twelfth/profiles/Styrene.pdf

http://www.dsmcompositeresins.com http://ntp.niehs.nih.gov/?objectid=ABD1DF87-A7F0-5D9B-0C6BA115E3117F5B http://echa.europa.eu/documents/10162/d96caf76-f7fe-40cb-acd1-7859a4d3071d http://www.cen-online.org http://ntp.niehs.nih.gov/?objectid=03C9AF75-E1BF-FF40-DBA9EC0928DF8B15 http://ntp.niehs.nih.gov/?objectid=03C9AF75-E1BF-FF40-DBA9EC0928DF8B15 http://ntp.niehs.nih.gov/ntp/roc/twelfth/profiles/Styrene.pdf http://ntp.niehs.nih.gov/ntp/roc/twelfth/profiles/Styrene.pdf

JEC COMPOSITES MAGAZINE - Issue #87 - March 2014 Special JEC Europe

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