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RE: [greenyes] Fw: [greenyes] Its polystyrene not styrofoam

To be correct to the point of being obnoxious, expanded polystyrene is typically used for packaging but may also be used for insulation. Extruded polystyrene aka "Styrofoam" of which there are half a dozen clones, is basically used for building insulation. Styrene is a building block to both of these products and other than some basic performance differences the key difference is that extruded polystyrenes use CFCs and HCFCs as blowing agents are known ozone depletors. The manufacture of expanded polystyrene will contribute to low level ozone problems (different ozone). Extruded products must eventually be re-engineered to meet the requirements of the Montreal Protocol unless, of course, the present administration chooses to renege on this as it has done on methyl bromide.
From a larger perspective, one can always make the argument that because extruded polystyrene has superior insulating properties, less pollutants are released from power plants. I think that's a stretch as acceptable alternatives such as polyisocyanurate are on the market with equal thermal characteristics.
I would speculate, and I'm sure a grassroots recycler would back me up, is that the real problem is with expanded polystyrene because it is so ubiquitous in the society as a packaging material with so little recycling opportunities. There are an increasing amount of agricultural based packaging and food service alternatives on the market now and one hopes common sense in the market would prevail.
Bruce Maine
Sustainable Products and Specifications Manager
Sustainable Design Services
HDR Architecture

-----Original Message-----
From: Rod [mailto:rodmuir@no.address]
Sent: Tuesday, March 16, 2004 3:56 PM
To: greenyes@no.address
Subject: [greenyes] Fw: [greenyes] Its polystyrene not styrofoam

Thanks for the clarification
4 real quick questions please
Why the switch from styrene to propylene?
Is this recent?
What is current ratio of use.
Is there a quick way to tell the difference?
Rod Muir
Waste Diversion Canada
----- Original Message -----
From: "Ann Schneider" <schneiderann@no.address>
To: <greenyes@no.address>
Sent: Tuesday, March 16, 2004 4:20 PM
Subject: [greenyes] Its polystyrene not styrofoam

> Hi All:
> Just to be nit picky, or to be technically correct, the term for this
> form of packaging is polystyrene not styrofoam. Styrofoam (tm) is a
> trademarked material from DuPont and is actually wall insulation boards.
> It is a material you would find in a construction or demolition site but
> is not what I think most of you are talking about, like the single use
> utensils and cups, loose fill packaging material or the block packaging
> material is actually polystyrene. Also the programs that collect
> polystyrene are probably collecting expanded polystyrene (eps) (e.g.,
> white coffee cups) not extruded polystyrene (e.g., forks, spoons and
> clear cups). Also note that much of the block packaging that looks like
> polystyrene is actually polypropylene and the two can not be mixed with
> out real problems at the end use manufacturing site.
> And just for the sake of history, one of the old issues with EPS was the
> blowing agent used to expand the plastic polymer. CFC and then HCFCs
> (chlorofluorocarbons) used to be used and were considered a threat to the
> ozone layer. The off gassing was a concern if a densifyer was going to
> be used to make the transportation of PS more cost effective. Over the
> years many manufacturers converted to CO2 (carbon dioxide) as the blowing
> agent. I haven't heard any recent concerns over off gassing of this
> greenhouse gas emission. Interested folks may want to go to the
> Institute of Packaging Professionals (IoPP) website to see what are the
> latest enviro concerns.
> Ann Schneider
> Mtn. View CA
> and former IWM Certificate Instructor & Coordinator
> UC Santa Cruz and San Jose State Univ.
> and nag for correct terminology
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