Killer Apparel and Bedding

Killer Apparel and Bedding

We”re all familiar with rechargeable batteries but rechargeable

fabrics? Last year I saw predictions that in the new millennium

we would have new fabrics in clothing that wouldn”t need

cleaning and in germ-killing sheets. At the time, I was somewhat

skeptical about the claims. Now, of course, I find an article in the

January 2000 issue of Discover magazine that makes it all seem

quite feasible. The article deals with such things as Teflon suits,

phase-change fabrics and rechargeable killer clothing. Not only

that, but it looks like those ink-jet machines we discussed last

week might be used to produce custom fabrics.

Just the other day, I was wearing my 20-year old Majer 100%

wool slacks that won”t wear out and a couple drops of oil dripped

onto them from my pizza, which I shouldn”t have been eating

anyway. A trip to the cleaners is obviously in order. Teflon may

be the answer. Apparently, Teflon is now being used by some

manufacturers to coat individual fibers so that the staining fluids

from pizza and the like will just roll right off, cutting cleaning bills

appreciably. Actually, this could also be a boon for harried

parents who have to worry about their drooling and clumsy

offspring soiling their bibs and other apparel. However, I suspect

that Teflon would not find a market in diapers, where absorbency

is critical?

But the next item, phase-change fabrics, really grabbed my

attention. We”re all well acquainted with phase changes, the most

ubiquitous being the phase change from liquid water to solid ice

or vice versa. In your Scotch on the rocks, the phase change not

only helps to dilute the possible overly relaxing effect of the

alcohol but also serves to keep the drink at a pretty constant

temperature. The reason for this is that it takes heat to melt ice,

something known as the heat of fusion (melting). Conversely,

when water freezes, heat is given off in the same amount. So, if

you want to keep something at a constant temperature for a long

period of time, find a substance with a phase change at that

temperature. Textile engineers are trying to do just that in an

attempt to counter that offensive characteristic of humans trying

to adjust to temperature swings, sweating. Excuse me, I should

have used the more erudite term, perspiration.

About ten years ago, a waxy compound was developed which

turns from solid to liquid in just the right temperature range for

potential use in pilots” gloves to keep their hands warm.

Unfortunately, cuts in the defense budget shelved the

development of this phase-change product. However, some

entrepreneurial types have taken this material and are marketing

boots and socks incorporating capsules of this wax, with the

socks having a ten-degree comfort zone. Another phase-change

approach is being tested using a compound known as

polyethylene glycol, or PEG for short. The PEG molecule is in

the form of a helix, like DNA. As the temperature changes the

molecule coils and uncoils, either giving off or absorbing heat.

Actually, this polymer does double duty. When PEG encounters

damp heat, i.e., sweat, it uncoils and traps the water and the heat.

Both effects are reversed when the wearer enters that air-

conditioned movie theater. Apparel incorporating PEG is

expected to be in your department stores within a year.

PEG also looks promising to the medical community. For some

reason, fabrics treated with this polymer aren”t good hosts for

microorganisms. This antibacterial property isn”t well understood

but the speculation is that microbes either can”t exist on the dry

fabric or perhaps the PEG alters the fabric in a way that the little

buggers just can”t hang on to the fibers. The FDA is currently

reviewing PEG-treated products such as bandages, scrubs for

doctors, bedding and blankets, footwear, dressings, etc.

If PEG-treated clothing doesn”t suit you, there is an alternative

killer fabric. There are compounds known as N-halamines,

whatever their formula, that are used in your local swimming

pools to stabilize the chlorine used to kill the germs. A company

in Seattle has found a way to attach the N-halamine molecules to

cotton. Now the cotton can offer chlorine atoms something to

hang on to and do their job of germ killing. Due out this year is a

line of chlorine-doped socks, uniforms, air filters, bandages etc.

Suppose the chlorine encounters so many little obnoxious critters

that it gets used up fighting them? You just recharge your

garment by washing it in the laundry with chlorine bleach. The

killer garment is loaded with chlorine, all set for another round of

bug fighting.

We”ve been talking about microbes so far. Are you as distressed

as I am about those millions of larger creatures we share our beds

with? Chances you”ve seen many pictures of these horrid looking

dust mites but yet have never heard of the fungus Aspergillis

repens. It never even occurred to me that the dust mites depend

on good old Aspergillis to break down those flakes of my skin to

form a suitable dish upon which the mites can dine. Now a

company in England has reportedly found that acrylic fibers can

be treated with a chemical that stops the fungus from

reproducing. As a result, Aspergillis fades away and the poor

dust mites starve to death. May they rest in peace!

While the above discoveries and applications seem quite

reasonable to me, the Discover article ends on a note that may be

stretching things just a bit too far. Apropos of last week”s

column, there is an Institute for Molecular Engineering, whose

president predicts that nano-manufacturing mills (like our plastic

spitting ink-jet printers) will spin out custom fabrics from the raw

materials such as carbon, nitrogen and oxygen. He envisions

sensors being incorporated into the fabric that will detect such

things as rips in the garment or the presence of specks of dirt.

These sensors will then dispatch nanorobots that will mend the

fabric or carry away the dirt to a collection area. Then this fellow

believes the tiny robots could circulate water throughout the

structure giving the equivalent of a rinse cycle!

Personally, I think the use of nanorobots for these frivolous duties

is truly beyond the pale. Better to concentrate on others” visions

of tiny nanorobots scooting through our bodies cleaning up fatty

deposits in our blood vessels or devouring cancer cells and the

like. Actually, I don”t expect to live long enough to see

nanorobots employed in any of these capacities but I hope I”m

wrong about the medical possibilities. My own arteries could no

doubt use a good scouring!

Allen F. Bortrum