. . . Is about optimizing technology
A polymer is a chain of small molecules joined
together in a repeating fashion to form a single
layer molecule. Chemists develop polymers so they
can be used to make ingredients for products with
unique physical and chemical properties. They
manipulate large, complex molecules and capitalize
on the connections between their molecular structure
and the properties that make them useful. Polymer
products can be lightweight, hard, strong, and
flexible and have special thermal, electrical,
and optical characteristics; they include products
from the fiber, communication, packaging, and
transportation industries.
The big boom in polymer chemistry occurred largely
in the first part of the twentieth century with
the advent of polymer materials such as nylon
and Kevlar®. Today, most work with polymers
focuses on improving and fine-tuning existing
technologies. Still, there are opportunities ahead
for polymer chemists. They work in many industries,
creating a variety of synthetic polymers such
as Teflon® and special application plastics
and developing new polymers that are less expensive
or that outperform traditional materials and replace
those that are scarce.
"The world is changing," says James
Shepherd, a research associate in polymer chemistry
at Hoechst Celanese. "New demands for polymer
materials will be coming down the line. What we
have learned over the past ten years will enable
us to fulfill new needs. We may not discover a
new polyethylene," he says, "but we
may find smaller-volume and potentially more cost-effective
materials."
. . . Is about research and business
There has been a shift in the economic emphasis
and focus of polymer chemistry. Shepherd says
when he began working in the field, many projects
were purely exploratory. "Only later would
we worry about the product." Now, projects
are evaluated at the outset on the basis of what
they will do for the company and what end-use
improvements they will deliver. Therefore, industrial
polymer chemists are increasingly in contact with
the sales and marketing divisions of their companies
and its customers.
This shift has placed a premium on good communication
and interpersonal skills. It means chemists must
adopt a business outlook in their work. Other
skills and disciplines also come into play. "It
helps if you are engineering-minded," says
Kate Faron, a senior research chemist at DuPont.
John Droske, professor of chemistry at the University
of Wisconsin-Stevens Point, agrees. "This
is a field for people who are comfortable looking
at the end use as well as the preparation."
Polymer chemistry is product-oriented. However,
this does not eliminate the availability of positions
outside of industry. Some polymer chemists pursue
their research interests in addition to their
teaching and administrative responsibilities through
employment at colleges and universities.
. . . Touches many scientific disciplines
Polymer chemistry touches many scientific disciplines
and is vital in fields that develop products such
as plastics and synthetic fibers; agricultural
chemicals; paints and adhesives; and biomedical
applications such as artificial skin, prosthetics,
and the nicotine patch that helps smokers overcome
their smoking habit. It is estimated that as many
as 50% of all chemists will work in polymer science
in some capacity during their careers. Because
they work in a field that is so broad, polymer
chemists must be flexible
and be able to interact and communicate with others
in a variety of disciplines.
Because polymer chemistry today is product oriented,
it has some overlap with materials science. However,
polymer chemists emphasize that the most important
aspect of their work is in the organic synthesis
of materials. Most Ph.D. chemists now in the field
were trained in organic chemistry. They acknowledge
the strengths of degree programs in polymer science,
but many say they would still choose to obtain
a solid background in organic chemistry before
entering the polymer science area. "You should
take polymer classes, but not without a strong
foundation in organic chemistry," says Jim
Mason, senior chemist in the polymers division
at the Bayer Corporation. "You learn a lot
on the job," he adds. He says that an employer
can teach you about polymers, but the fundamentals
should be learned while in school. Mason adds,
"Traditional training may also provide you
with more long-term job security." Faron
says, "It helps to be a generalist. If you
go into certain polymer programs, you could be
specializing too soon."
. . . Is a field open to change
"Things in the area of polymer chemistry
will be changing dramatically over the next five
to ten years because of the emphasis on 'green'
products," explains Shulman. "Ingredients
will have to be environmentally friendly, and
there will be an emphasis on making polymers biodegradable.
Concern about the effects of detergent products
on the environment has brought new activity to
a relatively mature area of polymer science."
Polymer is an exciting field with new frontiers
to be discovered.
Copyright 1994, 1997 American Chemical Society
Jim Mason Blending and Compounding
Today, there is almost no development of entirely
new polymer materials. However, blending and compounding
existing polymers has become an important part
of a polymer chemist's work. "Compounding
is both an art and a science," says Jim Mason,
a senior chemist in the polymers division of Bayer
Corporation. "Quite a bit of chemistry is
involved. You need to understand the reactions
that go on in an extruder-the machine used to
compound." Compounding is often done to achieve
certain properties needed for a particular application.
One of Mason's recent projects was to develop
a compounded polymeric material to be used in
the manufacture of lawn tractors. "Body panels
for these tractors are typically made of sheet
metal," Mason explains. "But many tractor
manufacturers would like plastics instead of sheet
metal in the body panels. Existing plastics were
not suited for this application, so we tried blending
different materials to come up with the right
combination of properties."
Mason worked directly with the tractor manufacturer
to find out what was needed. "One of the
big requirements was high impact strength,"
he says. "Then if the tractor hit a tree,
the material would not shatter. We also needed
to develop a material that had good weatherability
and could be mixed with pigment to get the right
color." The chemist and the customer collaborated
to develop a material that is suited for this
application.
James Shepherd, Liquid-Crystal Polymers
In the 1970s and 1980s, some of the most lucrative
polymer breakthroughs occurred in the area of
high-performance polymers. These materials were
expensive to produce but had new and desired qualities,
such as high strength and temperature resistance.
James Shepherd, research associate for polymer
chemistry at Hoechst Celanese, focuses on developing
new high-performance polymers. One example of
successful high-performance polymer technology
is liquid-crystal polymers (LCPs). LCPs are polymers
that are highly oriented; that means that when
they are heated above a certain temperature, the
molecules align and flow easily. The LCP can then
be pushed through a spinnaret on a spinning machine
and made into a fiber, or can be injected into
a small mold for an intricate part used in the
electronics business. One of the benefits of LCPs
is that they produce a material that is generally
much stronger than those produced from traditional
plastics. One aspect that Shepherd stresses is
the importance of teamwork. "How to make
the polymer is a team decision. There are so many
different aspects to bring together and different
talents required," he says. "It is not
just the people in the lab making the decision.
We monitor the changing needs of our customers
and then determine how to produce the material
with the properties they want."
An illustration of this, says Shepherd, was when
economics and environmental issues required the
molding industry to reuse the scrap material that
is a normal byproduct of molding plastic parts.
"One problem with doing this," he explains,
"is that repeated processing cycles can adversely
affect the properties of the material." However,
by adjusting the chemistry and processing characteristics
of a new LCP formulation, chemists in Shepherd's
lab developed a material that maintains its properties
after many processing cycles. In this way, basic
researchers brought together applications, chemists,
and customers to find a mutually beneficial solution.
Terry St. Clair Polymers for Aerospace/NASA
Polymer development at NASA occupies a unique
position in the field of polymer chemistry. Terry
St. Clair, head of the polymeric materials branch
at NASA Langley, explains that his work both serves
NASA's polymer materials needs and functions as
an incentive for the rest of industry to make
the best polymer materials possible. "Our
mission," he explains, "is to make sure
that the materials that aircraft companies need
are available. This, in some cases, forces industry
to offer a more optimized product than the one
they might want to push.
"We do a lot of the same type of polymer
work as is done in industry, but in a broader
and freer structure that is not confined by cost,"
he says. In some ways, this makes NASA a competitor
with other polymer makers, the difference being
that NASA does not actually manufacture large
quantities of polymer materials. In some cases,
St. Clair will work directly with an aircraft
company to develop the products it needs. "When
they have endorsed the material, we both go out
into the market to try to find someone to make
it," he says.
Another aspect of his job is to develop polymers
for highly focused applications, such as the scientific
instruments used in the space program. Staff in
St. Clair's lab were asked to make a polymer used
in the window of an X-ray telescope. "Only
about five pounds of this material was needed
annually," he says. "We were in a position
to develop an exotic polymer where cost was not
a factor. They would have been happy to use platinum
or gold if it would work."
[Photo courtesy DuPont Inc.]
Lycra spandex adds high-performance technology
to this casual shirt. The comfort and versatility
of Lycra spandex throughout the garment make it
appropriate for a range of activities.
Jan Shulman, Detergent Polymers
Jan Shulman, a formulation chemist at Rohm and
Haas, works with polymers used in automatic dishwashing
detergent products. "In this field, polymers
are key to making products work better,"
he says. One problem Shulman deals with is the
effects of sodium carbonate-or soda ash-in a dishwashing
detergent. "Soda ash is a main ingredient
in many formulations," he says. "But
when it reacts with water, it can form a chalky
film on glasses. When you add polymers to a formula,
you can prevent this from happening." Shulman
says his lab facility includes dishwashers, plates,
and glasses. "We basically replicate what
the consumer does at home and conduct research
to determine the most effective detergent formulation."
Shulman also works on formulation changes that
are needed to address concerns about the effects
of traditional detergent ingredients on the environment.
"Most of this work involves reformulations
around chlorine and phosphates," he explains.
Beginning in Europe in 1990, he says, there was
a move toward phosphate-free systems and an effort
to replace chlorine bleach with oxygen bleaches,
such as those found in Clorox 2. "Because
this trend was making its way to the United States,
it became my job to work on reformulating products,"
he says. "When you remove phosphates, you
need to add a polymer to enhance performance.
We try to determine which polymers will fit the
bill."
Kate Faron, Fibers
The general public is familiar with Lycra, or
spandex, the stretch fabric that goes into leggings,
fitness wear, and bathing suits. Kate Faron, a
senior research chemist at DuPont, knows Lycra
on the polymer level. Part of Faron's job is to
improve Lycra spandex for continued use in successful
fashion items. "When Lycra first replaced
rubber thread, the market grew in every segment,"
she explains. "We need to continue making
some changes to the fiber to keep growing. Most
of the changes that we make are incremental changes
to existing products; but we still seek step-change
improvements, and there is always a lot of chemistry
involved."
By changing the structure of the polymer or by
using chemical additives, Faron changes the properties
of the spandex polymer. For example, how it responds
to light and heat can be modified chemically.
"Certain fabrics that do not already include
Lycra might benefit from elastic properties,"
she says. "We change the polymer to meet
the specifications of these new materials. It
is macromolecular engineering," she says.
"You need to know how to synthesize small
molecules and incorporate them into larger ones.
You also have to understand the structure you
build and the properties you expect it to have."
John Droske, Polymer Education
"Approximately 50% of all chemists will work
with polymers at some time in their careers,"
says John Droske, professor of chemistry at the
University of Wisconsin-Stevens Point and director
of the POLYED National Information Center for
Polymer Education. "Because polymer science
touches on many areas, it is important for chemists
to be trained in polymer science." The POLYED
has been working with a National Science Foundation
grant to develop materials for polymer chemistry
courses at the undergraduate level.
Droske teaches courses on the synthesis and characterization
of polymers and the physical chemistry of polymers.
He also conducts a polymer lab course. The aspect
of polymer science that Droske enjoys most is
the challenge of working with large molecules.
"There is something unique about studying
polymers," he says. "Macromolecules
have a greater complexity than do small molecules.
Over the years, our understanding of these large
molecules has increased so much that, although
they remain complex, we have tools that provide
us with a better understanding of their properties,
enabling us to make connections between their
structure at the molecular level and their properties
at the use level."
WORK DESCRIPTION
Polymer chemists are concerned with the study
and synthesis of large, complex molecules. They
manipulate the molecular structure of a material
to develop functional characteristics in an end
product by chemical processing or through other
processing conditions.
WORKING CONDITIONS
Polymer chemists spend most of their time in the
lab; they also interact with materials scientists
or product manufacturing specialists in pilot
plant environments. Polymer chemists are increasingly
expected to think of the business opportunities
for the products developed from their work. Thus,
chemists may work with marketing or sales representatives
or directly with customers.
PLACES OF EMPLOYMENT
Polymer chemists are employed in industry, government,
and academia. However, most jobs are in industry
where products are made. Opportunities for polymer
chemists in industry exist in areas where adhesives,
coatings, synthetic rubber, synthetic fibers,
agricultural chemicals, packaging, automotive,
aircraft, aerospace, and biomedical industries
are made.
PERSONAL CHARACTERISTICS
A polymer chemist's work is interdisciplinary
in nature. Individuals should be able to communicate
with others in a number of fields. Those who are
interested in materials and the end use of polymers
as well as their synthesis will be particularly
well suited to the field. This is also be true
for individuals who like hands-on work as opposed
to purely theoretical thinking.
EDUCATION AND TRAINING
Most people employed in polymer chemistry have
a Ph.D. and were trained as organic chemists.
They stress the importance of a solid education
in the fundamentals of chemistry. However, they
acknowledge the value of the interdisciplinary
degree available through programs in polymer science.
JOB OUTLOOK
Because polymer science is product-oriented, hiring
can be expected to follow the economy. Polymer
chemists stress the need to remain as broad-based
and as flexible as possible for long-term employment
security, but creative and well-trained individuals
should be able to find positions in this field.
Most major chemical companies have made deep cuts
in their central research divisions, and industry
is still in a downsizing mode. The field remains
highly competitive, but some say they think these
dynamics are cyclical and that the job market
will improve.
SALARY RANGE
Starting salaries for chemists in polymer science
are in the high $40,000-per-year range for those
with a Ph.D., approximately $35,000-per-year for
M.S. degree holders, and in the mid $20,000-per-year
range for someone with a B.S. degree. The median
salary for a Ph.D. polymer chemist in industry
is estimated to be approximately $75,000-per-year;
$64,000-per-year for chemists working in government
labs; and $55,000-per-year for chemists in academia.
FOR MORE INFORMATION
POLYED
National Information Center for Polymer Education
University of Wisconsin-Stevens Point
Department of Chemistry
Stevens Point, WI 54481
(715) 346-3703
Society of Plastics Engineers
P.O. Box 403
Brookfield, CT 06804-0403
(203) 775-0471
WHAT YOU CAN DO NOW
Only a few colleges and universities have programs
in polymer science, so a student's best access
to experience in the field will be through internships
in industry or through summer employment at an
institution that has a polymers program.
American Chemical Society, Education Division,
1155 Sixteenth Street, NW, Washington, DC 20036;
(202) 452-2113.
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