Graduate
  1. Physical Chemistry  1.1. Thermodynamics  1.1.1. Laws of Thermodynamics  1.1.2. Enthalpy and heat capacity  1.1.3. Entropy and free energy  1.1.4. Phase Equilibrium  1.1.5. Statistical thermodynamics  1.1.6. Thermodynamic cycle  1.1.7. Fugacity and activity  1.2. Quantum Chemistry  1.2.1. Principles of quantum mechanics  1.2.2. Schrödinger Equation  1.2.3. Particle in a box  1.2.4. Operators and eigenvalues  1.2.5. Atomic orbitals  1.2.6. Molecular orbital theory  1.2.7. Perturbation theory  1.2.8. Valence bond theory  1.2.9. Hybridization and chemical bonding  1.3. Chemical kinetics  1.3.1. Rate laws and reaction mechanisms  1.3.2. Collision theory  1.3.3. Transition state theory  1.3.4. Enzyme Kinetics  1.3.5. Chain Reactions and Polymerization  1.3.6. Photochemical reactions  1.4. Statistical mechanics  1.4.1. Partitioning functions  1.4.2. Molecular distribution functions  1.4.3. Boltzmann Distribution  1.4.4. Bose–Einstein and Fermi–Dirac statistics  1.5. Spectroscopy  1.5.1. Rotational Spectroscopy  1.5.2. Vibrational Spectroscopy  1.5.3. Electronic Spectroscopy  1.5.4. Nuclear magnetic resonance spectroscopy  1.5.5. Mass Spectrometry  1.5.6. Raman Spectroscopy  1.5.7. Electron paramagnetic resonance spectroscopy  1.6. Surface and colloidal chemistry  1.6.1. Absorption isotherm  1.6.2. Surface tension and wetting  1.6.3. Colloidal Stability  1.6.4. Catalysis  1.6.5. Emulsions and micelles  1.7. Electrochemistry  1.7.1. Nernst equation  1.7.2. Electrochemical cells  1.7.3. Conductivity and mobility  1.7.4. War  1.7.5. Fuel cells  1.7.6. Electrolysis
  2. Organic chemistry  2.1. Reaction mechanism  2.1.1. Nucleophilic substitution reactions  2.1.2. Electrophilic addition reactions  2.1.3. Elimination reactions  2.1.4. Rearrangement reactions  2.1.5. Radical reactions  2.1.6. Pericyclic reactions  2.2. Spectroscopy and structural determination  2.2.1. UV-Vis Spectroscopy  2.2.2. IR Spectroscopy  2.2.3. NMR Spectroscopy  2.2.4. Mass Spectrometry  2.2.5. X-ray crystallography  2.3. Stereoscopic  2.3.1. Chirality and optical activity  2.3.2. Structural analysis  2.3.3. Geometrical isomerism  2.3.4. Dynamic Stereochemistry  2.4. Organometallic Chemistry  2.4.1. Organolithium and organomagnesium reagents  2.4.2. Palladium-catalyzed cross-coupling reactions  2.4.3. Transition Metal Complexes  2.4.4. Metal–carbon bond  2.5. Polymer chemistry  2.5.1. Polymerization mechanism  2.5.2. Polymer Characteristics  2.5.3. Biodegradable Polymer  2.5.4. Conducting polymer  2.5.5. Supramolecular polymers  2.6. Medicinal chemistry  2.6.1. Drug design and development  2.6.2. Pharmacokinetics and pharmacodynamics  2.6.3. Structure-activity relationships  2.6.4. Molecular docking and drug screening
  3. Inorganic chemistry  3.1. Coordination chemistry  3.1.1. Crystal field theory  3.1.2. Ligand field theory  3.1.3. Spectrochemical Series  3.1.4. Chelation and stability  3.2. Organometallic Chemistry  3.2.1. Metal Carbonyls  3.2.2. Catalysis by organometallic complexes  3.2.3. Metallocenes  3.3. Bio-inorganic chemistry  3.3.1. Metalloproteins and enzymes  3.3.2. The role of metals in biological systems  3.3.3. Metal ion transport and storage  3.4. Solid state chemistry  3.4.1. Crystal Structures  3.4.2. Band theory of solids  3.4.3. Superconductors  3.4.4. Defects in the crystal  3.5. Lanthanides and Actinides  3.5.1. Electronic configuration in lanthanides and actinides  3.5.2. Coordination chemistry of the lanthanides  3.5.3. Magnetic Properties of Lanthanides
  4. Analytical chemistry  4.1. Chromatography  4.1.1. Gas Chromatography  4.1.2. High Performance Liquid Chromatography  4.1.3. Thin Layer Chromatography  4.2. Spectroscopic Techniques  4.2.1. Atomic absorption spectroscopy  4.2.2. X-ray diffraction  4.2.3. Inductively coupled plasma spectroscopy  4.3. Electroanalytical methods  4.3.1. Potentiometry  4.3.2. Voltammetry  4.3.3. Colometry  4.4. Mass Spectrometry  4.4.1. Ionization Technique  4.4.2. Fragmentation Pattern  4.5. Chemometrics  4.5.1. Multidisciplinary analysis  4.5.2. Machine Learning in Chemistry
  5. Theoretical and Computational Chemistry  5.1. Molecular dynamics simulation  5.1.1. Force fields and energy minimization  5.1.2. Monte Carlo simulation in molecular dynamics simulations  5.2. Quantum chemical methods  5.2.1. Hartree–Fock theory  5.2.2. Density functional theory  5.2.3. Semi-empirical methods  5.3. Computational drug design  5.3.1. Molecular Docking  5.3.2. QSAR Modeling  5.3.3. Virtual Screening
  6. Biochemistry  6.1. Enzyme Kinetics  6.1.1. Michaelis-Menten kinetics  6.1.2. Inhibition mechanism  6.2. Metabolism and Bioenergetics  6.2.1. Glycolysis  6.2.2. Citric acid cycle  6.2.3. Electron transport chain  6.3. molecular Biology  6.3.1. DNA replication and repair  6.3.2. Protein synthesis  6.3.3. Gene Regulation  6.4. Structural Biochemistry  6.4.1. Protein Folding  6.4.2. Membrane Biophysics
  7. Environmental Chemistry  7.1. Atmospheric Chemistry  7.1.1. Greenhouse gases  7.1.2. Ozone depletion  7.1.3. Air pollutants and smoke  7.2. Water Chemistry  7.2.1. pH and water hardness  7.2.2. Wastewater treatment  7.2.3. Aquatic Chemistry  7.3. Soil Chemistry  7.3.1. Heavy metal contamination  7.3.2. Soil pH and Buffering  7.3.3. Nutrient cycling  7.4. Toxicology and Chemical Safety  7.4.1. Toxicokinetics  7.4.2. Risk Assessment in Toxicology and Chemical Safety in Environmental Chemistry  7.4.3. Effects of pollutants on the environment

Graduate → Organic chemistry ↓


Polymer chemistry


Polymer chemistry is an important and integral part of organic chemistry. It studies the chemical synthesis, structure, properties, and applications of polymers. Polymers are large molecules, or macromolecules, composed of many repeated subunits known as monomers. This branch of chemistry overlaps with many fields, including biochemistry, materials science, and engineering.

Basic concepts

To understand polymer chemistry, it is important to start with several basic concepts:

Monomers and polymers

Monomers are small, simple molecules that form the basic building blocks of polymers. When monomers undergo polymerization — an essential chemical reaction — they bond together to form long chains known as polymers. The properties of a polymer are highly dependent on its structure, which is determined by the monomers used, their arrangement, and the length of the polymer chain.

Monomer polymerization Polymer

Types of polymers

Polymers can be classified based on the origin of their monomers, their structure, and their synthesis mechanism:

  • Natural polymers: These are polymers obtained from nature. Examples include proteins, cellulose, and natural rubber.
  • Synthetic polymers: Created through various polymerization processes. Common examples are polyethylene, polystyrene, and polyvinyl chloride (PVC).
  • Addition polymers: Formed by addition reactions of unsaturated monomers. A well-known example is polyethylene, represented as -(-CH2-CH2-)-n.
  • Condensation polymers: Produced through condensation reactions where a small molecule such as water is eliminated. Terylene and nylon are examples.

Polymerization process

There are two main processes of polymerization: addition polymerization and condensation polymerization.

Addition polymerization

This process, also known as chain-growth polymerization, involves monomers with double bonds. This reaction is initiated by a free radical, an ion, or some other chemical agent, leading to the formation of long chains.

Initiator , Monomer polymer series

Consider the polymerization of ethylene to form polyethylene:

CH2=CH2 + initiator → -CH2-CH2-

Condensation polymerization

This step-growth polymerization involves monomers containing two functional groups. As the monomers join, they release a small molecule, often water or methanol, and form a covalent bond.

Monomer 1 , Monomer 2 Polymer + Small Molecule

A classic example of this is the production of nylon from adipic acid and hexamethylenediamine:

H2N-(CH2)6-NH2 + HOOC-(CH2)4-COOH → [-NH-(CH2)6-NH-CO-(CH2)4-CO-]n + nH2O

Polymer structures

The structure of polymers determines their properties and functionality. The characteristics of structure are as follows:

Linear, branched and cross-linked polymers

  • Linear polymers: Composed of monomer units linked in single straight chains. Example: polyethylene.
  • Branched polymers: Have side chains branched from the main long polymer chains. Example: Low density polyethylene (LDPE).
  • Cross-linked polymers: These contain chains linked to each other that form a network. Example: Vulcanized rubber.
Linear Branched Connected to the cross

Properties and applications

The properties of polymers can be tailored to suit different applications. Factors such as molecular weight, crystallinity and degree of polymerization affect their structural and functional characteristics.

  • Thermal properties: Some polymers, such as thermoplastics, melt when heated, allowing them to be reshaped. Examples include polyethylene and acrylic. Thermosetting polymers, such as epoxy resins, harden when heated and cannot be reshaped.
  • Mechanical properties: Polymers range from flexible to rigid depending on their structure. Nylon is known for its toughness, while polystyrene is more brittle.
  • Optical properties: Some polymers are optically transparent and are used in lenses and screens. For example, polymethyl methacrylate (PMMA).

Applications in daily life

The versatility of polymers makes them an integral part of many industries:

  • Packaging: Food and beverage packaging relies primarily on polymers such as polyethylene terephthalate (PET) and polypropylene.
  • Automotive industry: Polymers help reduce the weight of vehicles, thereby increasing fuel efficiency. Polyurethane is used extensively for interior and seat cushions.
  • Biomedical applications: Polymers such as poly(ethylene glycol) (PEG) and polylactic acid (PLA) play important roles in drug delivery systems, prostheses, and sutures.

The widespread use and adaptability of polymers have significantly influenced technological, environmental and economic development.

Environmental impact and sustainability

Despite their many benefits, polymers present environmental challenges. Plastic, a type of polymer, contributes significantly to landfills and marine waste. Efforts to improve sustainability include developing biodegradable polymers and increasing recycling methods.

  • Recycling: The recycling process helps reduce environmental impact and save resources. However, it is complicated due to the different types of polymers.
  • Biodegradable polymers: Developed to reduce pollution, these polymers decompose naturally in the environment. Polylactic acid (PLA) from renewable resources such as corn starch is an example.

Sustainable practices aim to strike a balance between polymer production and environmental care, without compromising functionality.

Conclusion

As an essential aspect of organic chemistry, polymer chemistry plays a vital role in innovation and progress in a variety of fields. Its ability to create new materials with diverse properties ensures that polymers will remain a vital component in future technological advancements and sustainable development.


Graduate → 2.5


U
username
0%
completed in Graduate

← Prev (2.4.4)
Metal–carbon bond
Next (2.5.1) →
Polymerization mechanism

Comments 



Polymer chemistry

https://www.chemistryelite.com/g/2.5?ceal=en