Not all coatings will hinder recyclability
Clare Goldsberry notes in her Page 9, Jan. 13 article, ``OEMs undertake quest for computer afterlife'' that fillers and coatings ``inhibit recyclability.''
The very real concern is that computer housings, or any plastic housings, for that matter, must be recyclable. For many years plastic enclosures, which were shielded with plated or sprayed-on shielding, could not be recycled. This still remains true of plated plastic, but it is no longer a problem with certain spray-applied coatings.
Most sprayed-on shielding contains a solvent carrier, which enables the metallic coating to bond to the plastic substrate. This bond, however, is so strong and permanent that it prevents the shield from being removed and does indeed inhibit plastic recyclability.
However, new water-based sprayed-on shielding for electromagnetic and radio frequency interference relies on a different bonding technique to the plastic. These materials are easily removed from the plastic and offer equivalent or better shielding effectiveness than their solvent-based predecessors.
Water-based paints are, to quote a need expressed in Ms. Goldsberry's article, ``environmentally friendly and greener.'' Water-based EMI/RFI shielding coatings also conform to Environmental Protection Agency restrictions on solvent emissions.
Bill Mc Leod
Recycler condemns large chemical firms
In reference to George Dreckmann's Page 10, Feb. 17 Perspective ``Consumers: Boycott PET bottles,'' Mr. Dreckmann's use of the word ``stupid'' hits the nail on the head. We all are! Let's not just hammer PET resin.
High density polyethylene, low density PE and polypropylene can be substituted for PET throughout his article.
I agree at the present that PET is the foul ball. A few years ago it was PE, then PP.
The American public needs to be aware it's not the recyclers that are gumming up the works but the giant major chemical companies playing with the markets and our depleting natural resources. In other words, our future.
Nation Plastics and its parent company, Wood Industries, are just upstarts in plastic recycling. We've only been collecting and recycling plastics for 43 years. We are only a small family business that survives on our own pocketbooks. We have never accepted government hand-outs.
Recycling has not just been our source of income, but our way of life. Our business has become harder and harder to keep afloat, mostly trying to outguess and outlast the whims of the giant chemical companies.
I sympathize with Mr. Dreckmann, but PET is not the only resin being manipulated. I think making the public aware of what the chemical giants are doing to us (America) is going to be the ultimate answer.
The chemical giants are like a gang of train robbers, robbing us all of our natural resources.