Polymer Chemistry and Physics Study Guide PDF

Polymer Chemistry and Physics Study Guide 1. Anionic Polymerization: Chain-growth polymerization initiated by an anion, typically using monomers with electron-withdrawing groups. 2. Atactic: A polymer chain lacking a regular arrangement of substituents along the backbone. 3....

Polymer Chemistry and Physics Study Guide 1. Anionic Polymerization: Chain-growth polymerization initiated by an anion, typically using monomers with electron-withdrawing groups. 2. Atactic: A polymer chain lacking a regular arrangement of substituents along the backbone. 3. Azo Compound: A compound containing the –N=N– functional group, often used as thermal initiators in radical polymerization. 4. Backbiting: Intramolecular chain transfer in radical polymerization, leading to short-chain branching. 5. Block Copolymer: A copolymer composed of blocks of different monomers covalently linked together. 6. Ceiling Temperature (Tc): The temperature above which the rate of depolymerization exceeds the rate of polymerization. 7. Chain-Growth Polymerization: Polymerization that proceeds by the rapid addition of monomers to an active center. 8. Chain Transfer: A process in radical polymerization where the active radical is transferred to another molecule, terminating the growing chain and potentially initiating a new chain. 9. Cohesive Energy Density: A measure of the energy required to separate molecules in a condensed phase, related to the strength of intermolecular forces. Complex Shear Modulus (G):* A complex number that describes the viscoelastic properties of a material, combining the storage modulus (G') and the loss modulus (G"). 10. Conformation: The spatial arrangement of atoms in a polymer chain that can be changed by rotation around single bonds. 11. Configuration: The spatial arrangement of atoms in a polymer chain that can only be changed by breaking and reforming bonds. 12. Copolymer: A polymer made up of two or more different monomers. 13. Copolymer Equation: An equation that describes the instantaneous composition of a copolymer based on the reactivity ratios of the monomers. 14. Crystallinity: The degree of structural order in a solid polymer, where chains arrange in a regular, repeating lattice. 15. Degree of Polymerization (DP): The number of monomer units in a polymer chain. 16. Diad: A sequence of two monomer units in a copolymer chain. 17. Dilatometry: A technique for measuring the volume change of a material as a function of temperature, often used to determine the glass transition temperature. 18. Dispersity (Đ): A measure of the breadth of the molecular weight distribution, calculated as the ratio of weight-average molecular weight to number-average molecular weight. 19. Dynamic Mechanical Analysis (DMA): A technique for studying the viscoelastic properties of materials by measuring their response to an oscillating stress. 20. End-Group Analysis: A method for determining the molecular weight of a polymer by quantifying the concentration of end groups. 21. Entanglement: The physical intertwining of polymer chains in a molten or concentrated solution, contributing to the viscosity and elasticity of the material. 22. Flory-Huggins Interaction Parameter (𝝌): A parameter that quantifies the interaction energy between polymer and solvent molecules. 23. Free Radical Polymerization: Chain-growth polymerization initiated by free radicals. 24. Freely Joined Chain: A theoretical model of a polymer chain where bond angles are not fixed, and the chain can adopt any conformation. 25. FTIR Spectroscopy: A technique that analyzes the absorption of infrared radiation by a material to identify functional groups and molecular structure. 26. Gel Effect: An autoacceleration of the polymerization rate due to increased viscosity at high conversion, hindering termination reactions. 27. Glass Transition Temperature (Tg): The temperature at which an amorphous polymer transitions from a glassy, brittle state to a rubbery state. 28. Graft Copolymer: A copolymer where chains of one monomer are grafted onto the backbone of another polymer. 29. Heterotactic: A polymer chain with alternating arrangements of substituents along the backbone. Huggins' Equation: An equation that describes the viscosity of dilute polymer solutions. 30. Inhibitor: A substance that completely stops radical polymerization by scavenging free radicals. Initiation: The first step in chain-growth polymerization, where an active center is formed that can add monomers. 31. Intrinsic Viscosity ([η]): A measure of the contribution of a polymer to the viscosity of a solution, extrapolated to zero concentration. 32. Ionic Polymerization: Chain-growth polymerization initiated by either a cation or an anion. Isotactic: A polymer chain with all substituents on the same side of the backbone. 33. Kinetic Chain Length (ν): The average number of monomer units added per initiating radical before termination. 34. Kuhn Length (Lk): The length of a hypothetical segment in a freely joined chain that has the same end-to-end distance as a real polymer chain with fixed bond angles. 35. Lamella: A thin, plate-like crystalline region in a semicrystalline polymer. 36. Living Polymerization: Polymerization with no termination steps, allowing for precise control of molecular weight and the synthesis of block copolymers. 37. Loss Angle (δ): A measure of the energy dissipation in a viscoelastic material, defined as the arctangent of the loss modulus divided by the storage modulus. 38. Loss Modulus (E"): The measure of the viscous component of a material's response to an oscillating stress, representing the energy dissipated as heat. 39. MALDI-TOF: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, a technique for determining the molecular weight distribution of polymers. 40. Mark-Houwink Equation: An empirical equation relating the intrinsic viscosity of a polymer to its molecular weight. 41. Melt Flow Index (MFI): A measure of the flowability of a molten polymer, often used to characterize the processability of thermoplastics. 42. Meso (m): A stereochemical designation for a pair of chiral centers in a polymer chain that have the same configuration. 43. Miscibility: The ability of two substances to form a homogeneous mixture. 44. Molecular Weight (M): The mass of a molecule, often expressed in g/mol. 45. Molecular Weight Distribution (MWD): The distribution of molecular weights in a polymer sample. Monomer: A small molecule that can react to form a polymer. 46. Network Polymer: A crosslinked polymer structure where chains are interconnected, forming a three-dimensional network. 47. Newtonian Fluid: A fluid where the viscosity is independent of the shear rate. 48. NMR Spectroscopy: A technique that uses the magnetic properties of atomic nuclei to analyze the structure, tacticity, and composition of polymers. 49. Non-Newtonian Fluid: A fluid where the viscosity changes with the shear rate. 50. Number-Average Molecular Weight (Mn): The average molecular weight calculated based on the number of polymer chains of each size. 51. Pentad: A sequence of five monomer units in a copolymer chain. 52. Persistence Length (Lp): A measure of the stiffness of a polymer chain, representing the length scale over which the chain direction persists. 53. Poisson's Ratio (ν): The ratio of the transverse strain to the axial strain in a material under uniaxial stress. 54. Polydispersity Index (PDI): Another term for dispersity (Đ), representing the breadth of the molecular weight distribution. 55. Polymer: A large molecule composed of repeating monomer units. 56. Polymer Blend: A mixture of two or more polymers. 57. Propagation: The step in chain-growth polymerization where monomers are added to the growing chain. 58. Racemic (r): A stereochemical designation for a pair of chiral centers in a polymer chain that have opposite configurations. 59. Radius of Gyration (Rg): A measure of the size of a polymer coil, defined as the root-mean-square distance of the chain segments from the center of mass. 60. Random Copolymer: A copolymer where the monomers are randomly distributed along the chain. Reactivity Ratios (r1, r2): Parameters that quantify the relative rates at which monomers add to a growing copolymer chain. 61. Retarder: A substance that slows down radical polymerization by reacting with free radicals but does not completely stop it. 62. Ring-Opening Polymerization: Polymerization where cyclic monomers are opened to form linear chains. 63. SEC Calibration: The process of establishing a relationship between the elution time of polymer standards in SEC and their known molecular weights. 64. Self-Catalyzed Polymerization: A step-growth polymerization where one of the monomers acts as its own catalyst. 65. Size Exclusion Chromatography (SEC): A technique for separating molecules based on their hydrodynamic volume. 66. Solubility Parameter (𝛿): A measure of the cohesive energy density of a material, often used to predict solubility and miscibility. 67. Solvent: The substance in which a solute dissolves to form a solution. 68. Spherulite: A spherical, semicrystalline structure formed by the radial growth of lamellae from a central nucleation point. 69. Step-Growth Polymerization: Polymerization that involves the stepwise reaction of functional groups. 70. Stereoregularity: The regularity of the arrangement of substituents along a polymer backbone. Storage Modulus (E'): A measure of the elastic component of a material's response to an oscillating stress, representing the energy stored during deformation. 71. Syndiotactic: A polymer chain with substituents alternating on opposite sides of the backbone. Tacticity: The stereochemical arrangement of substituents in a polymer chain. 72. Termination: The step in chain-growth polymerization where the active center is deactivated, stopping chain growth. 73. Tetrads: A sequence of four monomer units in a copolymer chain. 74. Theta Conditions: Conditions where the polymer chain adopts an unperturbed, random coil conformation due to balanced solvent-polymer and polymer-polymer interactions. 75. Triads: A sequence of three monomer units in a copolymer chain. 76. Trommsdorff-Norrish Effect: Another term for the gel effect, where viscosity increases at high conversion, leading to autoacceleration of the reaction rate. 77. Viscosity: A measure of a fluid's resistance to flow. 78. Viscometry: A technique for measuring the viscosity of a solution to determine the molecular weight of a polymer. 79. Weight-Average Molecular Weight (Mw): The average molecular weight calculated based on the weight fraction of polymer chains of each size. 80. Wormlike Chain Model: A theoretical model of a polymer chain that takes into account the chain stiffness, using a persistence length parameter. 81. Young's Modulus (E): A measure of a material's stiffness, defined as the ratio of stress to strain under tensile deformation.