Page 70 - Plastics News November 2018

teChnoLogy

Chemists develop safe alternatives Microorganisms help production

to phthalates used in plastics making it more cost-effective.

esearchers at UC Santa Cruz have developed safer ew biotechnological processes aim to simplify the
Ralternatives to the phthalate plasticizers used to Nuse of renewable biomass as an alternative to the
enhance the suppleness, flexibility, and longevity of fossil raw material and make it more cost-effective.
plastics.The problem with phthalates is that they leach Researchers at KIT are focusing on plant biomass
out of plastics into food, water, and the environment, such as wood and straw which is not used as food or
and there is mounting evidence suggesting that phthalate feed. ''To achieve sustainable and environmentally
exposure can lead to a variety of health problems. friendly energy and raw material supply, we need to
Researchers led by Rebecca Braslau, professor of chemistry develop innovative technologies which make the use of
and biochemistry at UC Santa Cruz, addressed this renewable biomass also attractive from an economic
problem by developing chemicals that are effective as point of view,'' says Professor Christoph Syldatk, Head of
the Institute of Process Engineering in Life Sciences II /
Technical Biology at KIT. His research group is examining
how raw materials that do not compete with food or
feed can be processed biotechnologically .

Researchers at KIT are examining, among other things,
how -- on the basis of lignocellulose fractions -- new
types of biosurfactants can be produced using microbial
or enzymatic synthesis.The aim is to convert the woody
biomass into basic components for the production of
chemicals and materials such as bioplastics. Bacteria,
yeasts and molds are among the microorganisms, the
plasticizers for polyvinyl chloride (PVC) but can't leach metabolism of which is used by researchers in the lab
out of PVC products because they are chemically bonded for such innovative product syntheses and chemical
to the polymer chain. The team reported their findings changes. Products can be manufactured using a bio-
in a paper published in the Journal of Polymer Science based process. Their molecules and properties are
Phthalates are used in a wide variety of products, but identical to those of petrochemical components. 'For
their most widespread use is as plasticizers for PVC, one
of the most common types of plastic. After polypropylene
and polyethylene, PVC is the third most common plastic
polymer and is used to make products such as building
materials, furniture, clothing, garden hoses, food
packaging, blood-storage containers, and medical devices.
Braslau's team has been working to develop "nonmigratory"
plasticizers that attach to the PVC polymer via a chemical
bond and can't leach out of the plastic. She explained that
traditionally, phthalates are mixed with fine-ground PVC
and "melted together" rather than being bonded."Unlike
phthalates, our nonmigratory plasticizers physically can't example, plastics can be equipped with a higher melting
leach out," Braslau said. Her lab has produced several point or greater gas permeability, and surfactants with
viable nonmigratory plasticizers, including two dubbed modified foam properties. ''We are trying to play around
the "frog" and the "tadpole" because of their chemical with bacteria in fundamental research to find out
structures. The "tadpole" is particularly promising because which functions the respective structures have, and if
it is much easier to produce than the "frog" and is the most possible to produce tailor-made compounds,'' says the
effective of the plasticizing strategies examined. biotechnologist.

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