A catalog record for this book is available from the Library of Congress. This terminology for discussing polymerization will be used in this textbook. to the area of polymer synthesis, with tens of thousand pages devoted to the .. This book is largely concerned with polymer synthesis, and in the following. The second part deals with how polymers are prepared from monomers and the The primary focus of the book is the ultimate property of the finished polymer.
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Seymour/Carraher's Polymer Chemistry: An Introduction, Fourth Edition, Revised introductory textbook is required that covers the entire field of polymer. the Permissions Department, John Wiley & Sons, Inc. Library of Congress Cataloging in Publication Data: Billmeyer, F~ed W. Textbook of polymer science. 𝗣𝗗𝗙 | This book has been written in a concise manner to include all fundamental aspects of polymer science including recent inventions in polymerizations and.
In the latter case, increasing the polymer chain length fold would increase the viscosity over times. Monomer arrangement in copolymers Main article: copolymer Monomers within a copolymer may be organized along the backbone in a variety of ways. A copolymer containing a controlled arrangement of monomers is called a sequence-controlled polymer. Alternating copolymers possess two regularly alternating monomer residues:  [AB]n structure 2 at right. An example is the equimolar copolymer of styrene and maleic anhydride formed by free-radical chain-growth polymerization. A statistical copolymer in which the probability of finding a particular type of monomer residue at a particular point in the chain is independent of the types of surrounding monomer residue may be referred to as a truly random copolymer   structure 3. For example, the chain-growth copolymer of vinyl chloride and vinyl acetate is random.
This material is perfectly stable outdoors and is formulated to resist exposure to UV light. The applications are flower pots, CD boxes, interior car parts and non-food packaging.
In both cases, the increase of lignin improves the biodegradation of the product by fungi. New research is being conducted into the idea of modifying lignin polymer using enzymes like peroxydase or laccase. The latter enzyme has now been commercialised by a Danish company, Novo Nordisk, and will certainly promote the commercial appearance of new lignin products.
Chitin and chitosan Chitin is one of the most widespread polysaccharides in nature and is particularly abundant in the cell walls of insect cuticles, of many fungal species and of shellfish or mollusc exoskeletons. The chemical composition of chitin is based on the repetition of the unit 2 acetamidedesoxy-D-glucose or Nacetylglucosamine Flieger et al.
Chitin is composed of a linear chain of acetylglucosamine groups Fig.
Most chitins and derivatives are extracted from crab shells, lobsters and shrimps or from the waste of fungi fermentation e. The swelling involves a modification of its natural crystal structure or. After washing in water, the recovered structure is chemically resistant due to the hydrogen bonds between the chains. The -chitin Classification of biodegradable polymers 13 1. It is also better adapted to be transformed by reactions such as acetylation, tosylation, tritylation and acetolysis.
The properties of chitosan depend strongly on the molecular characteristics molecular weight and degree of acetylation. Chitosan is soluble in water and in some organic solvents. The difference between chitin and chitosan is defined by their solubility in a dilute solution of weak acids. Chitosan dissolves in dilute acetic acid. It presents a unique combination of properties, brought about by its polysaccharide structure, large molecular weight, and a cationic character.
Chitin and chitosan are biocompatible and present antithrombogenic and hemostatic properties. These polymers can be extruded to make films for packaging applications. They are edible and can be used in the agricultural crop protection and food sectors, and also in wastewater treatment, textiles or cosmetics and toiletries.
They are also used for biomedical applications biomedical devices, and drug delivery systems.
Chitosan and its derivatives form air permeable films. This property facilitates cell regeneration when the films are used to protect tissues against microbiological attack.
For this reason chitin and chitosan are also good candidates for artificial skin, and biodegradable sutures. Producers of chitine and chitosan will not be presented here because there are 63 main companies; 30 are located in Asia, 14 in the USA, 12 in Europe, 6 in Canada, and one in Russia. Proteins are natural chains of -amino acids joined by amide linkages. They are degraded by enzymes proteases. The first industrial applications of protein as polymer were in the early s and s with casein and with soy protein.
Even though protein biopolymers did not develop as quickly as starch derivates, they remained present in some niche markets such as encapsulates pharmaceutical , coatings food industry , adhesives or surfactants Guilbert, They can be classified with animal proteins casein, whey, keratin, collagen and gelatine and in plant proteins wheat, corn, soy, pea and potato proteins Chiellini et al.
Collagen and gelatine Collagen and gelatine represent the most well-known animal polymers. Collagen is a relatively non-extensible protein presenting good stiffness. Gelatine derives from the physical and chemical denaturising of collagen.
The good quality of gelatine depends on its high solubility in hot water, its polyampholite character and its intrinsic ability to form thermally reversible gels.
Gelatine grades are also available in a wide range of viscosities. The classical applications are for the manufacturing of pharmaceutical products drug caps , for X-rays, photographic film development and food processing. As a biocompatible material, gelatine displays several advantages. It does not show antigenity and is resorbable in vivo. Its physico-chemical properties can be suitably modulated.
Gelatine can be plasticised thanks to the addition of water or of glycerol. There is, however, a limit to the use of this interesting material because there is a risk of viral animal contamination.
Finally blends of polyvinyl alcohol and gelatine are the object of studies and researches. Casein Casein is a natural polymer extracted from skim milk proteins.
It represents a small but important percentage of all the natural polymers used for the manufacturing of water-based adhesives. The casein formulations are highly soluble in alkaline solutions and in water. Casein polymers modified or not are mainly used in the manufacture of adhesives and the packaging industry for breweries, wineries and refrigerated products. Casein is also a binder for paints and an additive for adhesives formulations.
It can also be used as a plasticiser for concrete. Beyer Richard demonstrated the feasibility of preparing casein polymer to make edible films and for food products containing this polymer. Classification of biodegradable polymers 15 Wheat and corn gluten Polymers made from gluten are flexible, resistant, transparent, and completely biodegradable.
They are thermoplastic and present a yellow or slightly brown look. They are relatively impermeable to oxygen and to CO2 but are sensitive to humidity and do not give protection against desiccation. Potential applications are the production of soluble pockets for the controlled release of a chemical product e. The world-wide production of wheat gluten is about , tons per year. Moreover, as an edible material, gluten is a good candidate for food packaging or single units of coffee or other food.
In , Henry Ford presented a car body made from soybean-based materials. Soy proteins allow the development of various biodegradable materials. They are mainly formaldehyde-based thermoset composites.
Water resistance can be improved by adding polyphosphate fillers Otaigbe and Adams, Many applications have been developed thanks to its very high Young's modulus. A grade has also been formulated for medical applications. The plasticiser is the glycerol and aminopropyltriethoxi silane is used as coupling agent.
In India, many studies have been undertaken into the production of coextruded films of soy proteins with an aliphatic polyester. The research goal is to decrease the brittle character of the material.
Polypeptides of aspartic acid and lysine The wetting level of these polypeptide polymers in water is very high. They are now commercialised by Mitsui Chemical for horticultural applications. Some of these oily products are already well known by the public from their use in paint e. Plant oils increasingly become a source of raw material to produce thermoset resins that can be mixed with natural fibres in order to achieve light and resistant composite materials.
The combination of bio-based resins with natural fibres plant and poultry or 16 Biodegradable polymers for industrial applications 1.
These composites are used in agricultural equipment, automotive sheet-moulding compounds SMCs , civil and rail infrastructures, marine applications, housing and the construction industry Wool, The best candidates are triglycerides presenting a high level of unsaturation, and comprising active sites such as double bonds, allylic carbons, ester groups and carbons alpha to the ester group.
By using the same synthetic techniques that have been applied in the synthesis of petrochemical-based polymers, these active sites can be used to introduce polymerisable groups on the triglyceride Fig.
Castor oil contains ricinoleic acid presenting a hydroxyl group that allows polymer formation. This OH group participates in the formation of polyurethane and polyesters. Chemical functionalities such as aromatic or cyclic structures are introduced in the chemical structure of the triglyceride to improve stiffness in the polymer network.
The material produced with this kind of resin and reinforced with fibres shows very high mechanical properties e. The chemistry of thermoset resins made from plant oils could be addressed in a separate chapter. In this overview we will simply mention that from plant triglycerides, it is possible to produce polyolefins, polyurethane, polyesters, polyethers or polyamide resins. These Classification of biodegradable polymers Table 1. Table 1.
Generally, a decrease of the length of the aliphatic chain causes a decrease of the melting and glass transition temperatures. These products are easier to process and are more flexible. Most of these polymers are biocompatible and bioresorbable. This is why numerous applications, generally patented, are in the medical or veterinary sector implants, sutures. Nevertheless, certain companies have developed more usual products.
Polyhydroxyalkanoate PHA Polyhydroxyalkanoate is a polyester identified in by the microbiologist Maurice Lemoigne. It can be synthesised by various bacteria Alcaligenes Eutrophus, cyanobacteria.
There are numerous potential applications for PHA cosmetics containers, disposable articles, medical implants, paper coatings. Moreover, PHA can be formulated in many grades, from elastic products to crystalline ones, it is a good candidate for blends and easy to process with traditional equipment Whitehouse, It is naturally not crystalline, and is converted in a more crystalline form during the extraction process.
Research has been undertaken to avoid this transformation step that causes a decrease in the mechanical properties. Polymer science is now a thriving multidisciplinary scientific community. It is composed of scientists, engineers, technologists and industrialists from a very wide range of academic communities: mathematics, physics, chemistry, biology, chemical engineering, materials science and engineering, mechanical engineering, plastics engineering, dentistry, textile engineering, and many more.
What unites this disparate group is a belief that the material world contains substances that can best be understood in terms of extended macromolecular structures: polymers. While the word polymer simply means many repeat units, and while many actual substances that are not molecular in nature have been referred to as poly- mers, the present treatise will focus on the growth in understanding of substances that are genuinely macromolecular.
Since the Earth on which we live is filled with macromolecules, it might be supposed that an understanding of these substances would date from antiquity. However, most natural materials are mixtures, and detailed studies of these sub- stances needed to wait until Chemistry had progressed to the point where repro- ducible analyses could be carried out. I have chosen to start the story in the eighteenth century, when explorers brought back to Europe many fascinating substances and placed them in the hands of the best scientists of their day.
These materials were also eagerly embraced by technologists who wanted to produce items that would benefit humankind and enrich themselves. The free flow of materials and information that characterized the French community produced much great science and not a little benefit to humankind. The first materia polymerica chosen is caoutchouc, now routinely known as natural rubber.
Tree saps have played an important role in human culture. Styrene was discovered by heating Storax resin, and polystyrene was discovered by letting styrene sit undisturbed for a few months. Polystyrene has played a central role in the intellectual development of polymer science, but it did not become a com- mercial material until after the time period of this treatise.
The first commercially successful polymeric material synthesized entirely from inexpensive small molecules was Bakelite. The story of the discovery, develop- ment and understanding of Bakelite is a fascinating combination of pure G. Bakelite is a materia polymerica for the ages. Another ubiquitous earthly material is the class of carbohydrates.
They have been important to human civilization from the beginning. The understanding of the nature and structure of pure polysaccharides came relatively late in the prehistory of polymer science, but the first Nobel Prize associated with macromolecules was awarded to Sir Walter Norman Haworth in While individuals labor as scientists, they do so in the context of a community that considers the reported facts, evaluates the proposed theories and allocates honors and resources.
A fully visible community of scientists devoted to the macromolecular paradigm did not exist until the s. In order to help understand the emergence of this community, a brief history of the Faraday Society and its Discussions will be given.
A celebrated Discussion on polymerization in produced the kind of consensus that results in a large group of committed workers. The group photograph of this meeting includes most of the people that went on to define the initial paradigm period of polymer science. A concluding essay discusses the prehistory and evaluates the various forces that influenced the history of polymer science. Actual human culture is driven by multiple factors and is both more complicated and more interesting than ideo- logical stances.
Polymer science provides a rich milieu in which to explore the development of a scientific community. Chapter 2 2.
During his explorations in South America, he encountered the substance now known as natural rubber while in Ecuador , and sent back samples to the Academie Royale des Sciences in De la Condamine presented a paper by his collaborator Francois Fresneau before the Academie in , describing some of the properties of the substance dubbed caoutchouc .
He was the foremost French authority on Chemistry after Lemery and before Lavoisier . Macquers most famous work was his Dictionnaire de Chymie, which was initially published in and was revised and reissued in In Macquer published a paper in the Histoire de lAcademie Royales des Science on his own studies of caoutchouc .
One of the goals of this early scientific work was to purify the substance and to discover a suitable solvent, so that it could be easily processed. Macquer, like Fresneau, found that turpentine was a good solvent and that cast films retained their elasticity. Macquer was also able to dissolve caou- tchouc in carefully distilled and dried rectified ether .
Since ethyl ether does not occur in nature, it is notable that Macquer had a sufficient supply to use it as a solvent. Soon after caoutchouc was introduced in England, Joseph Priestley in discovered its use in removing pencil marks from paper , which led to its nickname: rubber.
People have been finding new uses for caoutchouc ever since. Caoutchouc began to appear in large compilations of chemical knowledge such as J.
Murrays A System of Chemistry . It was noted that the tree sap from the Hevea guianensis a type of Euphorbia could be separated into a firm elastic coagulum and a watery liquid.
The specific article on caoutchouc contains a clear declaration: The most remarkable physical property of which this substance is G.
The article in Murray also called attention to one of the most remarkable studies of caoutchouc carried out in by the Blind Philosopher of Kendall John Gough and published in the Memoirs of the Manchester Literary and Philosophical Society.
When a strip of caoutchouc was rapidly stretched, its temperature increased. Gough was well known for his ingenuity and used his lips to detect the rise in temperature. An even more remarkable experiment was described where a strip of rubber under tension from a suspended weight was heated. The strip was observed to shorten under heating!
Gough was a great teacher and influenced another Manchester notable, John Dalton! Another chem- ical test was dry distillation, one of the classic protocols of alchemy. Natural rubber yielded an empyreumatic oil under these conditions.
Caoutchouc soon became an item of commerce. The firm of Thomas Hancock developed a line of products based on both the elasticity and the water repellency of caoutchouc .
In order to learn more about the substance that was the basis of his wealth, in Hancock gave some caoutchouc to his friend Michael Faraday at the Royal Institution. Faraday was the foremost analytical chemist of this era. As was his custom, Faraday repeated the known experiments on Hevea tree sap, verified the ones that were true and became pro- ficient in the purification and processing of caoutchouc .
When fully purified and prepared as a solid block, caoutchouc is transparent. The good optical quality of pure caoutchouc led Faraday to carry out optical experiments. Relaxed and annealed caoutchouc is isotropic, both physically and optically. Despite their promise, cyclic polymers are still less explored than linear polymers like polyolefins and polycarbonates, which are widely used in daily life. Some critical issues, including controlling the molecular weight and finding suitable applications, remain big challenges in the cyclic-polymer field.
This review briefly summarizes the commonly used synthetic methodologies and focuses more on the attractive functional materials and their biological properties and potential applications. Keywords: click chemistry, cyclic polymers, metathesis, ring-closing polymerization, ring-expansion polymerization, zwitterionic ring opening 1 Introduction Polymers can be structurally classified as linear or cyclic.
Due to their topology and lack of chain ends, cyclic polymers are more compact and, thus, display smaller hydrodynamic volumes than their linear analogues. Therefore, cyclic polymers generally display unique physical properties such as higher glass-transition temperatures Tg , lower intrinsic viscosities, and longer retention times tR by gel permeation chromatography GPC. Although most of the existing functional materials are based on linear polymers, increasing effort is now given to cyclic polymer research in order to develop new synthetic protocols and new functional materials with unique properties and potentially important applications.