bioplasticsMAGAZINE_0904

Materials
PSM –The
Renewing of a Brand
Article contributed
by Daniel Tein,
VP of North American Sales,
PSM North America,
Warrenville, Illinois
As the world of bioplastics becomes more and more a mainstream industry,
it seems it is also destined to become more and more confusing.
Everything from inadvertent greenwashing to intentional misrepresentation
is now commonplace in the eco-movement of bio-materials.
Unfortunately, PSM (plastarch material) from PSM (HK) Co. Ltd in Hong Kong
is not exempt from such treatment. PSM’s claim to fame is its large percentage
of starch content. This allows it to maximize the heat stability of the
finished product. There are few, if any, bioplastics available today that can
really match up to PSM’s heat tolerance. This makes PSM, which uses only
non-GMO (non-genetically modified) starch sources, a very appealing material
for a wide swath of applications. As a material, PSM is ASTM D6400-04
compliant up to a full 2.5mm of thickness, has a melting point of 156°C, and
softening point around 127°C.
Despite its success, or perhaps due to it, there has been quite a few
instances of counterfeit PSM, both in resin form, and in finished products. PSM
is currently manufactured in China with plans to expand production globally.
Coincidentally, much of the counterfeit products in question originate from
China and Southeast Asia. Other companies have been producing and selling
‘PSM‘ resin, only to have the finished product become moldy within weeks.
Counterfeit products in certain niche markets have become out-of-hand. For
example, nearly 90% of the starch cutlery sold in the USA is made from plastic
blended PSM. PSM North America have started stating, ‘if you didn’t buy it
from us or a source authorized by us, assume it’s not PSM’.
Despite these unfortunate distractions, PSM is looking forward to
improving the material for use in more applications. Previously, PSM was
limited heavily to thermoforming and injection molding applications. Recent
engineering breakthroughs now allow PSM to be used in extrusion blow
molding, injection blow molding, as well as blown film applications. Foaming
applications currently are still limited to packaging void fill. Commercialized
PSM applications vary widely from foodservice and green construction
materials to packaging and consumer goods. PSM does not intend to stop
there. It is planned to introduce PSM for use in foam extrusion and coating
applications.
When asked how a manufacturer using Polypropylene could make an
immediate ecological impact with their products, the answer is easy: “PSM is
incredibly compatible with PP such that a dry mix is all that is needed; there
is no need to re-pelletize or compound. Even if a relatively small percentage
of PSM is blended with PP, this can be a first step towards eco-friendliness
without impacting product performance or base cost. By mixing with plastics,
plastics processors can immediately have a partly biobased component to
their offerings, however – not biodegradable – of course. This allows the
producer to tell a sustainable/renewable story. For a compostable compliant
product, PSM should be used as a 100% standalone material.”
www.psmna.com
34 bioplastics MAGAZINE [04/09] Vol. 4