Subject: Tt: DuPont goes biodegradable

From: RT Ellsberry <[email-masked]>
Date: Sat, 27 Sep 1997 12:51:38 -0400 (EDT)

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 In a fancy pro-environment advertisement in September's 'Scientific
 American,' the chemical giant claims that its next generation of
 affordable plastics will rapidly compost into viable topsoil.
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	... DuPont scientists have created a new family of highly
	versatile polymers based on polyethylene terephthalate (PET)
	technology and known commercially as DuPont Biomax(R) hydro/
	biodegradable polyester.  Depending on the application, up
	to three proprietary aliphatic monomers are incorporated into
	the polymer.  The monomers create weak spots in the polymeric
	chains, thereby making them susceptible to degradation through
	hydrolysis.  The large polymer molecules are cleaved by moisture
	into smaller molecules, which are then consumed by naturally
	occurring microbes and converted to carbon dioxide and water.

	A polyester that microbes find tasty.
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	Biomax(R) can be recycled, incinerated or landfilled, but is
	intended mainly for disposal by composting and in-soil degra-
	dation.  Researchers performed a series of tests to determine
	environmental impact, including plant germination and seedling
	emergence, earthworm weight gain and mortality, and microbial
	population density.  In all tests, the materials were found
	to be harmless to the environment at every stage in the decom-
	position process.  They are virtually undetectable to the un-
	aided eye in about eight weeks.

	Because Biomax(R) is a modified PET polymer, it can be manu-
	factured with existing equipment using existing bulk monomers.
	This means that it is only marginally more expensive to produce
	than PET itself.  Currently available degradable materials, on
	the other hand, can cost twice as much ...

 Further info available by fax from DuPont, Dept. SA, at 302-695-7615.
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