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The art of using chemical agents for medication dates back into
antiquity, although most of the earliest examples used plants,
herbs, and other natural materials. The old Egyptian medical
papyri, which date from before 1400 B. C., contain dozens of
examples of such medicinal plants and animal extracts. In the Old
Testament of the Bible, we can find references to using oil to
soften the skin and sores (Isaiah 1:6), the use of tree leaves for
medicine (Ezekiel 47:12) and various medical balms (Jeremiah 8:22).
Not all these recipes were effective in curing the ailments for
which they were used and sometimes the treatment was worse than the
disease. Nevertheless, the art of using chemical derived agents for
medicines continued to develop and received great impetus during
the present century with the rise of synthetic organic chemistry.
One of the most vexing problems has always been to achieve
specifici ty with the medications. While some medical agents do
indeed possess a relatively high degree of specificity, most agents
are far more systemic than would be desired. Much of the research
efforts to correct this deficiency has centered on modifying the
chemical agents themselves. Unfortunately, there are severe
limitations in this approach since minor modifications often
drastically affect the therapeutic activity and can even render the
drug completely ineffective, or worse."
Polymer modifications represent a valuable synthetic approach to
unique polymer compositions, structure, and properties not readily
available by the direct polymerization of monomers. Modified
polymeric products already exist in the commercial world (modified
celluloses, for example) so the approach is not new. However, it is
an interesting and chaU nging opportunity to develop new materials
for a variety of specialty applications using the "chemistry on
polymers" approach. This book contains papers presented at the
symposium on Polymer Modification held at the National American
Chemical Society Meeting in Orlando, Florida, August, 1996. The
chemistry presented is broad ranging, and includes grafting and
chemical oxidation reactions, and many other chemical
modifications. Hopefully, the book will be both a resource and an
inspiration for the reader to develop new opportunities for his or
her particular applications. CONTENTS SURF ACE MODIFICATIONS The
Preparation of Methyl Methacrylate/Methacrylic Anhydride Copolymers
from PMMA and Dialkyl Amines via Reaction Extrusion . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . 3 Michael P. Hallden-Abberton Grafting of Hindered
Amine Groups on EPDM and Polyoctenamer via Photo- Hydroperoxidation
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11 J. Lacoste, S. Chmela, J. Pellet, and J. F. Pilichowski Reactive
Gases as Reagents for Polymer Films Chemical Modifications . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . 21 J. F.
Pilichowski, S. Commereuc, 1. Lukac, G. Teissedre, and J. Lacoste
The Synthesis of Hydrophobe-Modified Hydroxyethyl Cellulose
Polymers Using Phase Transfer Catalysis . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . 31 Emmett M. Partain The
Synthesis and Characterization of Polyesters Derived from L-Lactide
and Variably-Sized Poly(Caprolactone) . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . 45 Michael R.
Lostocco and Samuel J.
Some have predicted that the coming several decades will be the
decades of "biotechnology," wherein cancer, birth defects, life
span increases, cosmetics, biodegradation, oil spills and
exploration, solid waste disposal, and almost every aspect of our
material life will be affected by this new area of science. There
will also be an extension of emphasis on giant molecules: DNA,
enzymes, polysaccharides, lignins, proteins, hemoglobin, and many
others. Biotechnology has been defined in various ways. In one
sense, this field is older than human history and references to the
human use of biotechnology-derived materials can be found in the
oldest human writings, such as the Bible. In this book,
biotechnology refers to the direct usage of naturally occurring
materials or their uses as a feedstock, including the associated
biological activities and applications of these materials.
Bioactive polymers, on the other hand, are polymers which exert
some type of activity on living organisms. These polymers are used
in agriculture, controlled release systems, medicine and many other
areas. The papers in this book describe polymers which essentially
combine features of biotechnology and bioactivity.
Although in nature the vast majority of polymers are condensation
polymers, much publicity has been focused on functionalized vinyl
polymers. Functional Condensation Polymers fulfills the need to
explore these polymers which form an increasingly important and
diverse foundation in the search for new materials in the
twentyfirst century. Some of the advantages condensation polymers
hold over vinyl polymers include offering different kinds of
binding sites, their ability to be made biodegradable, and their
different reactivities with various reagents under diverse reaction
conditions. They also offer better tailoring of end-products,
different tendencies (such as fiber formation), and different
physical and chemical properties. Some of the main areas emphasized
include dendrimers, control release of drugs, nanostructure
materials, controlled biomedical recognition, and controllable
electrolyte and electrical properties.
For there is hope of a tree, If it be cut down, That it will sprout
again And that the tender branch Thereof will not cease. Job XIV
(7) Mankind has been blessed with a multitude of resources. In the
beginning he utilized almost soley replenishable items such as
vegetation and animal protein, for both nourishment and shelter.
Gradually, such metals as copper and iron were developed and
replaced wood as a material of construction. Cement and glass,
although more plentiful than other minerals, also replaced the use
of growing sub stances. Coal and oil became the primary sources of
heat and power. Closer to the focus of this book, petroleum
products began to replace the vegetable oils, tannin, wool, cotton,
leather, silk, rubber, etc. in a host of applications. Surely, it
was argued, the new materials did the job better and cheaper. What
they didn't say is that soon we would run out of oil. In any case,
research on growing natural products, now called renewable
resources, slowed, and these industries sought only to maintain
their status quo. The 20th Century saw an unprecedented emphasis
and dependence on nonrenewable resources as energy sources
(petroleum, coal, ura nium) and the fabric of technology (drugs,
clothing, shelter, tires, computer parts). The predawn of the 21st
Century brings a reali zation that a cyclic shift back towards the
use of renewable re sources for technological application is in
order."
Research on metal-containing polymers began in the early 1960's
when several workers found that vinyl ferrocene and other vinylic
transition metal u -com plexes would undergo polymerization under
the same conditions as conventional organic monomers to form high
polymers which incorporated a potentially reactive metal as an
integral part of the polymer structures. Some of these materials
could act as semi-conducters and pos sessed one or two dimensional
conductivity. Thus appli cations in electronics could be visualized
immediately. Other workers found that reactions used to make simple
metal chelates could be used to prepare polymers if the ligands
were designed properly. As interest in homo geneous catalysts
developed in the late 60's and early 70's, several investigators
began binding homogeneous catalysts onto polymers, where the
advantage of homo geneous catalysis - known reaction mechanisms and
the advantage of heterogeneous catalysis - simplicity and ease of
recovery of catalysts could both be obtained. Indeed the polymer
matrix itself often enhanced the selectivity of the catalyst."
The first concern of scientists who are interested in synthetic
polymers has always been, and still is: How are they synthesized?
But right after this comes the question: What have I made, and for
what is it good? This leads to the important topic of the
structure-property relations to which this book is devoted.
Polymers are very large and very complicated systems; their
character ization has to begin with the chemical composition,
configuration, and con formation of the individual molecule. The
first chapter is devoted to this broad objective. The immediate
physical consequences, discussed in the second chapter, form the
basis for the physical nature of polymers: the supermolecular
interactions and arrangements of the individual macromolecules. The
third chapter deals with the important question: How are these
chemical and physical structures experimentally determined? The
existing methods for polymer characterization are enumerated and
discussed in this chapter. The following chapters go into more
detail. For most applications-textiles, films, molded or extruded
objects of all kinds-the mechanical and the thermal behaviors of
polymers are of pre ponderant importance, followed by optical and
electric properties. Chapters 4 through 9 describe how such
properties are rooted in and dependent on the chemical structure.
More-detailed considerations are given to certain particularly
important and critical properties such as the solubility and
permeability of polymeric systems. Macromolecules are not always
the final goal of the chemist-they may act as intermediates,
reactants, or catalysts. This topic is presented in Chapters 10 and
11."
''A must for anyone interested in metal-containing polymers and all
its aspects.'' ---American Scientist ''Nicely
organized...well-written....An excellent shapshot of the current
state of this field.'' ---MRS Bulletin, July 1998
Research on metal-containing polymers began in the early 1960's
when several workers found that vinyl ferrocene and other vinylic
transition metal TI -complexes would undergo polymerization under
the same conditions as conventional organic monomers to form high
polymers which incorporated a potentially reactive metal as an
integral part of the polymer structures. Some of these materials
could act as semi conductors and possessed one or two dimensional
conductivity. Thus applications in electronics could be visualized
immediately. Other workers found that reactions used to make simple
metal chelates could be used to prepare polymers if the ligands
were designed properly. As interest in homogeneous catalysts
developed in the late 60's and early 70's, several investigators
began binding homogeneous catalysts onto polymers, where the
advantage of homogeneous catalysis - known reaction mechanisms and
the advantage of heterogeneous catalysis - simplicity and ease of
recovery of catalysts could both be obtained. Indeed the polymer
matrix itself often enhanced the selectivity of the catalyst. The
first symposium on Organometallic Polymers, held at the National
Meeting of the American Chemical Society in September 1977,
attracted a large number of scientists interested in this field,
both established investigators and newcomers. Subsequent symposia
in 1977, 1979, 1983, and 1987 have seen the field mature. Hundreds
of papers and patents have been published."
Although in nature the vast majority of polymers are condensation
polymers, much publicity has been focused on functionalized vinyl
polymers. Functional Condensation Polymers fulfills the need to
explore these polymers which form an increasingly important and
diverse foundation in the search for new materials in the
twentyfirst century. Some of the advantages condensation polymers
hold over vinyl polymers include offering different kinds of
binding sites, their ability to be made biodegradable, and their
different reactivities with various reagents under diverse reaction
conditions. They also offer better tailoring of end-products,
different tendencies (such as fiber formation), and different
physical and chemical properties. Some of the main areas emphasized
include dendrimers, control release of drugs, nanostructure
materials, controlled biomedical recognition, and controllable
electrolyte and electrical properties.
Polymer modifications represent a valuable synthetic approach to
unique polymer compositions, structure, and properties not readily
available by the direct polymerization of monomers. Modified
polymeric products already exist in the commercial world (modified
celluloses, for example) so the approach is not new. However, it is
an interesting and chaU nging opportunity to develop new materials
for a variety of specialty applications using the "chemistry on
polymers" approach. This book contains papers presented at the
symposium on Polymer Modification held at the National American
Chemical Society Meeting in Orlando, Florida, August, 1996. The
chemistry presented is broad ranging, and includes grafting and
chemical oxidation reactions, and many other chemical
modifications. Hopefully, the book will be both a resource and an
inspiration for the reader to develop new opportunities for his or
her particular applications. CONTENTS SURF ACE MODIFICATIONS The
Preparation of Methyl Methacrylate/Methacrylic Anhydride Copolymers
from PMMA and Dialkyl Amines via Reaction Extrusion . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . 3 Michael P. Hallden-Abberton Grafting of Hindered
Amine Groups on EPDM and Polyoctenamer via Photo- Hydroperoxidation
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11 J. Lacoste, S. Chmela, J. Pellet, and J. F. Pilichowski Reactive
Gases as Reagents for Polymer Films Chemical Modifications . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . 21 J. F.
Pilichowski, S. Commereuc, 1. Lukac, G. Teissedre, and J. Lacoste
The Synthesis of Hydrophobe-Modified Hydroxyethyl Cellulose
Polymers Using Phase Transfer Catalysis . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . 31 Emmett M. Partain The
Synthesis and Characterization of Polyesters Derived from L-Lactide
and Variably-Sized Poly(Caprolactone) . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . 45 Michael R.
Lostocco and Samuel J.
Some have predicted that the coming several decades will be the
decades of "biotechnology," wherein cancer, birth defects, life
span increases, cosmetics, biodegradation, oil spills and
exploration, solid waste disposal, and almost every aspect of our
material life will be affected by this new area of science. There
will also be an extension of emphasis on giant molecules: DNA,
enzymes, polysaccharides, lignins, proteins, hemoglobin, and many
others. Biotechnology has been defined in various ways. In one
sense, this field is older than human history and references to the
human use of biotechnology-derived materials can be found in the
oldest human writings, such as the Bible. In this book,
biotechnology refers to the direct usage of naturally occurring
materials or their uses as a feedstock, including the associated
biological activities and applications of these materials.
Bioactive polymers, on the other hand, are polymers which exert
some type of activity on living organisms. These polymers are used
in agriculture, controlled release systems, medicine and many other
areas. The papers in this book describe polymers which essentially
combine features of biotechnology and bioactivity.
The art of using chemical agents for medication dates back into
antiquity, although most of the earliest examples used plants,
herbs, and other natural materials. The old Egyptian medical
papyri, which date from before 1400 B. C., contain dozens of
examples of such medicinal plants and animal extracts. In the Old
Testament of the Bible, we can find references to using oil to
soften the skin and sores (Isaiah 1:6), the use of tree leaves for
medicine (Ezekiel 47:12) and various medical balms (Jeremiah 8:22).
Not all these recipes were effective in curing the ailments for
which they were used and sometimes the treatment was worse than the
disease. Nevertheless, the art of using chemical derived agents for
medicines continued to develop and received great impetus during
the present century with the rise of synthetic organic chemistry.
One of the most vexing problems has always been to achieve
specifici ty with the medications. While some medical agents do
indeed possess a relatively high degree of specificity, most agents
are far more systemic than would be desired. Much of the research
efforts to correct this deficiency has centered on modifying the
chemical agents themselves. Unfortunately, there are severe
limitations in this approach since minor modifications often
drastically affect the therapeutic activity and can even render the
drug completely ineffective, or worse."
Introduction to Polymer Chemistry provides undergraduate students
with a much-needed, well-rounded presentation of the principles and
applications of natural, synthetic, inorganic, and organic
polymers. With an emphasis on the environment and green chemistry
and materials, this fourth edition continues to provide detailed
coverage of natural and synthetic giant molecules, inorganic and
organic polymers, elastomers, adhesives, coatings, fibers,
plastics, blends, caulks, composites, and ceramics. Building on
undergraduate work in foundational courses, the text fulfills the
American Chemical Society Committee on Professional Training (ACS
CPT) in-depth course requirement
Carraher's Polymer Chemistry, Tenth Edition integrates the core
areas of polymer science. Along with updating of each chapter,
newly added content reflects the growing applications in
Biochemistry, Biomaterials, and Sustainable Industries. Providing a
user-friendly approach to the world of polymeric materials, the
book allows students to integrate their chemical knowledge and
establish a connection between fundamental and applied chemical
information. It contains all of the elements of an introductory
text with synthesis, property, application, and characterization.
Special sections in each chapter contain definitions, learning
objectives, questions, case studies and additional reading.
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