ALBUQUERQUE, N.M. - Like many other discoveries in the plastics industry, Gary Estepp came by his by mistake. An engineer and former research scientist with Princeton Plasma Laboratories, Estepp was testing materials and composites for use in high-voltage electric insulators when he got an idea for a much lower tech, but potentially more widely used product.
``I was working with commingled plastic scrap and various chemicals,'' he said in a telephone interview, ``and I tried mixing it with this particular bunch of chemicals. What I got was unsuitable for insulators, but I filed it and came back to it later with another idea.''
In early 1995, Estepp founded Innovative Recycling Corp. to make I-Rock, a blend of plastic materials commingled with metals, glass and other waste, that has double the tensile strength of concrete and about half the weight.
His process is made without using any heat.
He set up a pilot plant in Albuquerque, and currently extrudes about 4 tons daily of the I-Rock material.
``Right now we use it to make traffic stops, extruded fence rails, guardrails and pallets,'' he said. ``We find that it is stronger than concrete and completely reusable. Since there is no melting involved, it is quite a bit cheaper than normal plastic extruded material.''
While the exact formula for mixing the composite is propri-etary and patented, Estepp said mixing the commingled waste plastics, along with the metal, glass and other material components of the waste supply, breaks down some of the plastics, and allows them to bond with the others, eliminating the need for glue, adhesives or melting.
``When you consider that the city of Albuquerque alone produces about 200 tons per day of scrap plastic that gets landfilled, you can see that there is plenty of supply, and the fact that we don't have to clean or sort any of it, makes it very inexpensive,'' said Estepp. ``We simply grind it into quarter-inch particles, blend it with the chemicals, and extrude it.''
He said he wants to build up the capacity of his Albuquerque plant to 30 tons per day and then might consider setting up an even larger facility to produce I-Rock.
Estepp said side-by-side comparison testing of I-Rock against oak pallets show that the plastic material will bear 3 to 4 tons, while wood bears about 2 to 3 tons and weighs 78 pounds for a normal pallet, against 60-80 pounds for wood, and 91-94 pounds for other plastic pallets.
I-Rock, can also be painted with any acrylic-based paint, widening its potential uses beyond pallet and road and construction applications.
It is resistant to chemical permeation and fungal and insect infestation.
``If you understand that disposable wooden pallets cost $8-$16,'' Estepp said, ``you recoup your money after three uses of an I-Rock pallet, and it can be used about six times. The same is true of other applications.''
Estepp said I-Rock pallets cost $25-$38 each, depending on size and style