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Chemistry of Polymers, Especially Plastics

• Polymers are giant organic molecules assembled from smaller molecules called monomers.
• Polymers are long chains of repeating monomer units, sometimes with branching or cross-linking between the chains.
• Polymerization is the chemical reaction that forms polymers from monomers.
• Plastics are a common type of synthetic polymer, suitable for molding or shaping.
• Examples of natural polymers include polypeptides (proteins like silk, collagen, and keratin), polysaccharides (carbohydrates like cellulose, starch, and glycogen), and nucleic acids (DNA and RNA).
• Examples of synthetic polymers include plastics, elastomers (like rubber), and fibers.
• Silicones have backbones of alternating silicon and oxygen atoms.
• Polyethylene, polystyrene, and more are examples of common polymers.
• Specific polymers like collagen and silk are detailed in the slides.

Definition of Polymers

• Polymers are giant organic molecules.
• Polymers are assembled from many smaller molecules called monomers.
• Polymer chains can have branching or cross-linking between the chains.
• Polymers are analogous to necklaces made from many small beads (the monomers).
• Polymerization is the reaction that forms polymers from monomers.
• Plastics are a type of synthetic polymer.

Types of Polymers

• Natural Polymers:
  • Polypeptides (e.g., proteins like silk, collagen, keratin)
  • Polysaccharides (e.g., cellulose, starch, glycogen)
  • Nucleic acids (e.g., DNA, RNA)
• Synthetic Polymers:
  • Plastics: Solids with various properties.
  • Elastomers: Solids with rubber-like qualities (e.g., rubber, silicones).
  • Fibers: Solid materials of intermediate characteristics (e.g., those in clothing).

Examples of Polymers: Collagen and Silk

• Collagen and silk are natural polymers.
• Their structures are shown in the presentation.
• Silk monomers are amino acids.

Examples of Polymers: Polyethylene

• Polyethylene is a common synthetic polymer.
• Its structure is based on repeating ethylene units.
• Images and diagrams illustrating polyethylene are presented in the material.

Examples of Polymers: Polystyrene

• Polystyrene is a synthetic polymer frequently used in various applications.
• It is formed from styrene monomers.
• Diagrams and images for polystyrene are included.

History of the Development of Synthetic Polymers

• Key dates and discoveries related to the development of synthetic polymers are presented, including inventions, processes, researchers, and materials.
• Significant dates include the vulcanization of rubber, the creation of cellulose nitrate, the development of linoleum, and the invention of various plastics.
• The presentation provides historical context, with innovators and advancements in the creation of polymers.

History of the Development of Synthetic Polymers (additional)

• Key figures (companies, individuals) involved in the development of synthetic polymers and plastics.
• Major inventions (e.g., plastic, synthetic fibers) and the years they occurred.
• The evolution of materials/processes in the polymers field.

Homogeneous vs. Heterogeneous Polymers

• Homogeneous: Polymer backbone is a continuous chain of carbon atoms.
• Heterogeneous: Polymer backbone has other atoms interrupting the carbon chain, sometimes referred to as a "heteroatom".
• Examples of each type and descriptions of their structures are given.

Homopolymers vs. Copolymers

• Homopolymers: Made of repeating monomers.
• Copolymers: Made of at least two different monomers, arranged in varying order.
• Different copolymer types are illustrated, including alternating, random, block, and graft copolymers.
• Examples of each type and their applications.

Mechanisms for Polymerization

• Addition Polymerization (Chain Growth):
  • Occurs from compounds with double bonds.
  • A catalyst initiates the reaction.
• Condensation Polymerization:
  • Forms polymers from monomers, releasing a byproduct such as water.
  • Examples involving monomers like bifunctional acids and bifunctional amines are shown.

Free Radical Mechanism of Addition Polymerization

• The steps (initiation, propagation, termination) of the process are detailed.
• The role of alkyl groups in the reaction is explained.
• The diagrams show the bonding mechanisms involved.

Polymers from Addition Polymerization: Vinyl Polymers

• Various vinyl polymers and their properties and applications are discussed.
• Different examples and types of vinyl polymers are detailed.
• The structures and usage details of many commonly seen polymers are presented.

Copolymers

• Descriptions and examples of various copolymers are provided.
• Different types of copolymers, including ABS, SBR, and ABR, are introduced.
• Various structural relationships with applications and uses are presented.

Condensation Polymerization

• Formation of polymers by joining monomers through the loss of a small molecule (e.g., water).
• Example of nylon-6,6 is described and demonstrated.
• Descriptions of the process and byproducts presented in the slide.

Hydrogen Bonding in Nylon 6,6

• Hydrogen bonding occurs between the linear chains in the nylon-6,6 polymer.
• Details of the bonding mechanism are illustrated.

Polyamide Kevlar and Some Products

• Kevlar is a high-strength polyamide fiber.
• Kevlar's properties and applications are explained.
• The slide's components provide a general overview.

Polyesters

• Polyesters are formed by ester linkages rather than amide linkages.
• The formation of polyethylene terephthalate (PET) is one example.
• Illustrations and explanations of ester formation and the polymer are provided.

Elastomers (Elastic Polymers)

• Elastomers are a class of polymers with elastic properties.
• Descriptions of the characteristics and properties are provided.
• Rubber, and isoprene-based materials are discussed and examples shown.

Cross-Linking

• The reduction of freedom in polymer chains due to cross-linking is explained.
• Detailed understanding of cross-linking effects and its practical applications, like vulcanized rubber.

Silicones (Polysiloxanes)

• Silicones are polymers with a backbone of silicon and oxygen atoms.
• Properties such as heat resistance and flexibility are noted and illustrated for understanding and general usage.

Foam

• Polyurethane, polyvinyl chloride, polystyrene are examples of commonly used polymers that are foams.
• Formation of foams and the chemical reactions are described; specifically showing gas release and how foams are made and used.

Epoxies

• Epoxy resins are thermosetting polymers used as adhesives and coatings.
• Reactions between bisphenol A diglycidyl ether and other components are presented.
• The materials, reactions, and properties are explained and demonstrated.

Fibre Composites

• Fiber composites, specifically materials like those found in the aerospace field, are explained and demonstrated.
• Properties including strength and light weight and their use in construction and manufacturing are specified.
• Specific examples, like the Boeing 787 are cited and analyzed.

Plastic Rigidity (Function of Temperature)

• The relationship between temperature and the rigidity of different plastics is examined.
• The properties are explored in detail.

Polycarbonate

• Polycarbonate is a hard, tough plastic used in various applications.
• Properties and examples of its usage (such as in packaging, and other applications) are detailed and presented.
• The manufacture process of polycarbonate (phase transfer catalysis) is shown.

Table 10.2: Plastics Used in Packaging

• Uses of different packaging materials are outlined and summarized.
• Comparison of different types of plastics used in packaging.
• Characteristics such as strength, flexible, rigid, etc. are explained and demonstrated.

Plastics in Packaging

• Various packaging plastics and their uses are detailed.
• Strength, rigidity, recycling, environmental impact, and other factors are included when appropriate for the summary.

Potential Problems of Plastic Containers

• Environmental, health, chemical release, and other problems associated with plastic containers and the polymers used are summarized.

Recycling

• Codes for different types of plastics' recycling programs and their usage are illustrated.

Biodegradable Plastics

• This section details biodegradable plastics that contain ester or amide linkages.
• Examples, processes, and general applications are provided.

Chemistry in Daily Life: Fibers

• This discusses the categorizations of fibers.
• The categorizations are summarized, and general applications of the various types are presented.

Natural Fiber: Cotton

• The structural components of the natural fiber 'cotton' are shown and explained.
• Properties are presented and illustrated.

Natural Fiber: Silk

• Illustrations and descriptions for the natural fiber 'silk' are discussed.
• Properties, components, and the products derived from silk are specified and demonstrated.

Product From Silk

• Pictures and text about products derived from silk and related traditional and historical knowledge are demonstrated.

Semi-synthetic Fiber

• Illustrations demonstrate both cellulose acetate and cellulose xanthate.
• Descriptions and properties are presented.

Synthetic Fiber

• Nylon-6,6 is the presented example;
• The properties and relationships with the manufacture process and the various applications are summarized and demonstrated diagrammatically.

Fiber for Sporting

• Kevlar and Lycra are presented as the examples;
• The structure, components, and properties are analyzed and described and used for specific sporting products.

Properties of Fibers

• Properties of various types of fibers (like strength, flexibility, resistance to chemicals) are detailed in organized table format.