I found this fabric comparison at; http://teakli.com/fabric.html

A lot of you are probably familiar with some of the
important characteristics of the common textile
fabrics. However, others may not understand the
difference between manufactured fabrics. For
example, do you know the advantages of say,
acetate, acrylic and polyester? When working with
or selling textile products, it is important to
understand the characteristics of the fabrics used
in the fabrications you deal with. All fabrics are not
the same, and their properties and advantages
can vary widely.

MANUFACTURED FABRICS
It is important to understand that all manufactured fabrics
are not alike. Each fabric has a unique composition and it's
own set of physical properties. The U. S. Federal Trade
Commission has established generic names and
definitions for manufactured fabrics, including acetate,
acrylic, lyocell, modacrylic, nylon, polyester,
polypropylene (olefin), rayon, and spandex. However, all
fabrics under a generic name are not exactly the same.
fabric producers have been able to modify the basic
composition of each generic fabric, both chemically and
physically, to produce variations which provide a softer
feel, greater comfort, brighter/longer lasting colors, better
warmth/cooling, moisture transport/wicking, and better
properties for blending with other fabrics. These improved
fabrics are given a trademark name and are owned and
promoted by the fabric producer. The following is a list of
producers of manufactured fabrics and their trademark
names.

ACRYLIC
Man-made
Characteristics:
Light-weight, soft, warm with a wool-like hand
Dyes to bright colors with excellent fastness
Outstanding wickability
Machine washable, quick drying
Resilient; retains shape; resists shrinkage, &
wrinkles
Flexible aesthetics for wool-like, cotton-like or
blended appearance
Excellent pleat retention
Resistant to moths, oil and chemicals
Superior resistance to sunlight degradation
Static and pilling can be a problem
Major End Uses:
Apparel - sweaters, socks, fleece, circular knit
apparel, sportswear, childrenswear
Home Fashion - Blankets, throws, upholstery,
awnings, outdoor furniture, rugs/floor coverings
Comments - Acrylic is a soft drapeable fabric
which provides warmth without being heavy, and it
takes color beautifully. Although acrylic has
traditionally been a fall/winter fabric, with a
wonderful resemblance to wool, Monsanto's
product development department has recently
developed some light weight circular knits and
blends which lend themselves to trans-seasonal
dressing as well. Acrylic is comfortable to wear. It
feels like wool. Yet, it is easy care and is machine
washable or dry cleanable.

POLYESTER
Man-made
Characteristics:
Strong
Crisp, soft hand
Resistant to stretching and shrinkage
Washable or dry-cleanable
Quick drying
Resilient, wrinkle resistant, excellent pleat
retention (if heat set)
Abrasion resistant
Resistant to most chemicals
Because of its low absorbency, stain removal
can be a problem
Static and pilling problems
Major End Uses:
Apparel - essentially every form of clothing,
dresses, blouses, jackets, separates, sportswear,
suits, shirts, pants, rainwear, lingerie,
childrenswear
Home Fashion - curtains, draperies, floor
coverings, fabric fill, upholstery, bedding.
Comments - This is probably the fabric that you're
most familiar with, of all the man-made fabrics. You
are aware that it's the best wash-and-wear fabric.
Unfortunately, because of the over-saturation of
polyester 20 to 30 years ago, some consumers
have acquired a kind of negative perception about
the fabric. But, what's exciting today is that, like all
the other man-made fabrics, new developments in
polyester are beginning to create a new attitude
towards the fabric. This is true, not only for
manufacturers and designers, but also for
consumers. In addition, when polyester is blended
with other dry-clean only fabrics, like wool, acetate,
or rayon, the durability of the blended fabric
improves and, in some cases, the fabrics can
even be made washable, if the percentage of
polyester is high enough.

RAYON
Man-made, cellulosic-based from wood pulp
Characteristics:
Soft and comfortable
Drapes well
Highly absorbent
Dyes and prints well
No static, no pilling problems
Fabric can shrink appreciably if washing
dry-clean-only rayon
Washable or dry cleanable. Read the label!
Major End Uses:
Apparel - Blouses, dresses, jackets, lingerie,
linings, millinery, slacks, sportshirts, sportswear,
suits, ties, work clothes
Home Fashion - bedspreads, blankets, curtains,
draperies, sheets, slip covers, table cloths,
upholstery.
Comments - One of the major characteristics of
rayon, also called viscose, centers around the
care of the fabric. For those of you who have
been around rayon a lot, you know that there are
both washable and "dry clean only" rayons in the
garments that you sell. Why are there both
washable and non-washable rayons? Originally
rayon was a "dry clean only" fabric. However, the
fabric producers discovered that they could create
washability in rayon by putting certain finishes on
the surface of the fabric after it was knitted or
woven. But this also added to the price. So, today
many rayons in the marketplace remain untreated,
and are therefore "dry clean only".
It's very important to read the labels, and make
the customer aware that just because he or she
may have purchased a washable rayon last week,
that doesn't mean that all rayons are washable.
Anytime a rayon garment, labeled "dry clean only",
is washed, a risk is taken, and one of three things
may happen. First the garment can shrink
tremendously, sometimes as much as two or
three sizes. Second, the garment may fade, or a
printed pattern may bleed. And third, the fabric
may lose its soft hand. The rayon that was once
soft and drapeable may become stiff and harsh.
There's also something important to remember
when caring for the washable rayons. Most of the
washable rayon garments today are labeled "hand
wash, cool water, drip dry or dry flat". And, it's
important that these directions are followed,
because when rayon is wet, it actually loses 30%
to 50% of its strength. So, hand washing, like the
label says, is the best. The constant agitation of
the washer, and tumbling of the dryer will beat the
garment against the side of the washer and dryer.
And, eventually this causes the fabric to break
down, and shorten the life of the rayon garment.
So, in order to get the maximum life out of your
washable rayon garment, it's best to hand wash
and drip/hang dry.

WOOL
Natural, Animal fabric
Characteristics:
Comfortable
Luxurious, soft hand
Versatile
Lightweight
Good insulator
Washable
Wrinkle-resistant
Absorbent
Easy to dye
Major End Uses:
Apparel - sweaters, dresses, coats, suits,
jackets, pants, skirts, childrenswear, loungewear,
blouses, shirts, hosiery, scarves.
Home Fashion - carpets, draperies, upholstery,
blankets.
CARE OF FABRICS
As important as buying the right fabrication is
understanding how to take proper care of it. The
following are general care tips for cleaning and
caring for garments containing the natural and
manufactured fabrics used in apparel and home
fashions.
However, always read and follow the care
instructions and any warnings in the garment
label.