Chemical Sciences

Definitions and classifications. Natural and synthetic macromolecules. Omopolymers and copolymers. Macromolecular classification as a function of their mechanical properties. Examples of polymer materials. Configurational characteristics. Random flight chain. Gyration radius of macromolecules. Conformational characteristics and semiempirical calculations of the potential energy of a macromolecule. Different defects of the polymer chain. Different structures of proteins. Outlines of polymer solution behaviour. Variation of mixing entropy of a polymer solution. Volume fractions. Flory temperature. Excluded volume concept for a polymer in solution. Polymer molecular weights and their distribution. Determination of the polymer molecular weights: Number and weight average molecular weights. Z-average molecular weight. Viscosity average molecular weight. Mark-Houwink-Sakurada equation. Gel Permeation Chromatography. Morphological features of the polymer crystal. Fringed micelle model. Lamellar long spacing of polymer cristals. Chain folding. Kinetic theory of the polymer crystallization. Elongational force field influence on the polymer crystallization. Polymer crystallization from melt. Spherulites. Annealing process. Roe experiment. Thermal properties of polymers. First and second order thermodynamic transitions. Thomson-Gibbs equation. Melting temperature and polymer-structure correlations. Thermal transitions evidenced by the dynamomechanical spectroscopy. Structure effects on the glass transition. Rheologial and mechanical properties of polymers. Stress-strain diagrams of different materials. Viscous behaviour of polymer materials. WLF equation. Rubber elasticity. The electrical behaviour of polymers. Inorganic and organic semiconductors. Polyacetylene synthesis and doping. Polymerization reactions. Mechanism and processes of polymerization. Polymerization kinetic. Numerical exercises on the determination of molecular weights, polymerization average grade, polymerization yield, polydispersity index of condensation and chain polymers.

Ciardelli F., Farina M., Giusti P., Cesca S., Macromolecole. Scienza e Tecnologia Vol. I e II, Pacini Editore Guaita M., Ciardelli F., La Mantia F., Pedemonte E., Fondamenti di Scienza dei Polimeri, Pacini Editore Helias H. G., Macromolecules, J. Wiley Billmayer F. W., Textbook of Polymer Science, Interscience Publishers, New York, London W. Hellerich, G. Harsch, S. Haenle, Prontuario delle Materie Plastiche, Tecniche Nuove Flory P. J., Principles of Polymer Chemistry, Cornell University Press Young R. J., Lovell P. A., Introduction to Polymers, CRC Press

Written examination plus oral examination to increase the mark

Lectures and numerical exercises in the classroom and practical exercises in the laboratory.

Definitions and classifications. Natural and synthetic macromolecules. Homopolymers and copolymers. Macromolecular classification as a function of their mechanical properties. Examples of polymer materials. Configurational characteristics. Random flight chain. Gyration radius of macromolecules. Conformational characteristics and semiempirical calculations of the potential energy of a macromolecule. Different defects of the polymer chain. Different structures of proteins. Outlines of polymer solution behaviour. Variation of mixing entropy of a polymer solution. Volume fractions. Flory temperature. Excluded volume concept for a polymer in solution. Polymer molecular weights and their distribution. Determination of the polymer molecular weights: Number and weight average molecular weights. Dynamic and static light scattering. Z-average molecular weight. Viscosity average molecular weight. Mark-Houwink-Sakurada equation. Viscosity of polymers in solution. Newtonian, pseudoplastic, dilatant, thixotropic, rheopectic fluids. Overlap concentration. Gel Permeation Chromatography. Morphological features of the polymer crystal. Fringed micelle model. Lamellar long spacing of polymer crystals. Chain folding. Kinetic theory of the polymer crystallization. Elongational force field influence on the polymer crystallization. Polymer crystallization from melt. Spherulites. Annealing process. Thermal properties of polymers. First and second order thermodynamic transitions. Thomson-Gibbs equation. Melting temperature and polymer-structure correlations. Thermal transitions evidenced by the dynamo mechanical spectroscopy. Structure effects on the glass transition. Polymer synthesis: mechanisms and processes. Step polymerizations: polycondensations, polyadditions, use of bifunctional monomers, polyfunctional monomers. Cross-linked, branched, star-polymers. Reaction mechanism, degree of conversion (p) and number average degree of polymerization (Xn), kinetics of polymerization. Chain polymerizations: Radicals, Initiation, Propagation, Termination, Structure of polymers from radical polymerization: head-to-tail and head-to-head structures, branching, stereo regularity, self-acceleration, inhibition and delay, Distribution of molecular weights, Effect of Temperature, Ionic polymerizations, living polymerizations. Cationic and anionic polymerization. Initiators, Monomers, Solvents. Controlled radical polymerizations. Coordination polymerization: stereo-control. Ziegler Natta and metallocene catalysts. Mechanism. Polymers for special applications. Data processing and interpretation of physical properties (mechanical and thermal properties, average molecular weight calculation). Laboratory practice: synthesis of polymers, preparation of hydrogels.

Knowledge of fundamentals of mathematics, physics, organic and chemico-physical chemistry learned in the first two years of the chemical sciences bachelor.

Adopted texts - Ciardelli F., Farina M., Giusti P., Cesca S., Macromolecole. Scienza e Tecnologia Vol. I e II, Pacini Editore - Guaita M., Ciardelli F., La Mantia F., Pedemonte E., Fondamenti di Scienza dei Polimeri, Pacini Editore - Elias H. G., Macromolecules (4 volumi), 2009, Ed. Wiley (eBook Sapienza) - Robert J. Young and Peter A. Lovell, Introduction to Polymers, 2011, CRC Press (eBook Sapienza).

frontal lectures and numerical exercises

Class attendance is optional. Attendance of laboratory exercises is mandatory.

Oral examination

Handbook of Polymers (Second Edition), edited by G. Wypych ChemTec Publishing 2016 sapienza e-book DOI https://doi.org/10.1016/B978-1-895198-92-8.50002-1

frontal lectures and laboratory experiments

Definitions and classifications of Macromolecules Configurational characteristics of polymers. Definition of Macromolecule, Polydispersity, Monomer, Repeating unit, Degree of polymerization, Oligomers, Telomers, Telechelic Polymers, Polyelectrolytes, Macroions and Macroradicals. Types of macromolecules Polymers of natural origin or synthetic. Homopolymers and copolymers: Linear homopolymers, Linear alternating copolymers, Linear block copolymers, Statistical linear copolymers. Branched polymers; Crosslinked polymers; Ladder polymers; Comb polymers (comb); Dendrimers. Classification according to mechanical properties. Configurational characteristics of polymer chains Polymers containing double bonds in the repeating unit; Polymers containing carbon atoms asymmetric in the repeating unit; Isotactic polymers; Syndiotactic polymers; Ditactic polymers; Erythro-di-isotactic polymers; Threo-di-isotactic polymers; Erythro-di-syndiotactic polymers; Threo-disindiotactic polymers. Conformational characteristics of polymer chains The model of the random flight chain: Case of the chain with constrained bond angle, Case of the chain with constrained internal rotation angle; The characteristic ratio; The radius of gyration. Conformers or Rotamers or Conformational Isomers; Conformational degrees of freedom; The possible conformations; Semi-empirical calculations of potential energy for the determination of the possible conformations; Torsional Energy, Van der Waals Energy, Colombian Energy, Hydrogen Bond Energy; The coefficients of the potential functions; Potential energy map of n-butane; Map of the potential energy of polyethylene. Types of defects in the polymer chain; The various types of protein structure: primary, secondary, tertiary and quaternary structure. Mechanisms and processes of polymer synthesis Step-growth polymerizations: polycondensations, polyadditions, use of bifunctional monomers, polyfunctional monomers and obtaining crosslinked, branched, star polymers; reaction mechanism; Conversion degree (p) and numerical average degree (Xn); Polymerization kinetics. Chain Polymerizations: Radicals, Initiation, Propagation, Termination; Structure of polymers from radical polymerization: head-to-tail and head-to-head linkages, branching, stereoregularity; Self-acceleration phenomenon; Inhibition and Delay; Molecular weight distribution; Effect of Temperature; Ionic Polymerizations (Cationic, Anionic): Initiators, Monomers, Solvents; Ex. of polymerization; Stereospecific (coordination) polymerizations Ziegler Natta: Mechanism; Notes on Polymerization processes. Notes on the behavior of polymers in solution Ideal sand regular Solutions; Polymer solutions; Variation of mixing entropy; Volume fractions; Flory temperature; Volume excluded. Molecular weights, their distribution and techniques for their determination Number average molecular weight; Measurement techniques of Mn. Weight Average Molecular Weight, Mw Measurement Techniques: Light Scattering, Case of Light Scattering in a Gas, Case of Light Scattering in a Solution with Point Particles, Debye Equation, Case of Light Scattering in a Solution with Particles non-point-like, Zimm Plot. Ultracentrifugation, Average molecular weight z, Sedimentation rate. Viscosity average molecular weight, Huggins and Kramer equations, Mark-Houwink-Sakurada equation. Gel Permeation Chromatography, Average Molecular Weight GPC. Morphological aspects related to the solid state of polymeric materials The fringed micelle model. The crystalline structure of polymers. The single crystals; Types of folds; Crystallization from solution. Crystallization from the melt: Spherulites. Annealing, Roe's experiments. Thermal behavior of polymeric materials Thermal transitions of polymeric materials: 1st order thermodynamic transitions; Determination of the thermodynamic or equilibrium melting temperature; Causes of Melt Peak Enlargement; Dependence of Tm on the heating rate; Thomson-Gibbs equation; Tm-structure correlations; The change in entropy at fusion; 2nd order thermodynamic transitions; The glass transition. Effects of chemical structure on Tg; Effect of polarity on Tg; Effect of molecular weight on Tg; Effect of crosslinking on Tg. Mechanical and rheological properties of materials Types of behavior of materials; Types of solicitations; Types of measures. Stress-strain diagram; Characteristics of stress-strain curves; Fiber stress-strain curves; Deformations and free energy. Viscous flow: Dynamic and kinematic viscosity, Newtonian behavior, Pseudoplastic behavior, Dilatant behavior, Plastic behavior, Time-dependent behaviors, Measurement techniques; Dependence of viscosity on molecular weight, Dependence of viscosity on branching and polydispersity, Dependence of viscosity on temperature; WLF equation. Dynamo-mechanical technique and complex module. Elastomers, The typical behavior of elastomers, Stress-strain curve of the elastomer, Elasticity of entropy. Examples of polymers for advanced applications

There are no prerequisites but for a better understanding of the topics of the course, it is considered essential to have basic knowledge of Organic Chemistry I.

Ciardelli F., Farina M., Giusti P., Cesca S., Macromolecole. Scienza e Tecnologia Vol. I e II, Pacini Editore Guaita M., Ciardelli F., La Mantia F., Pedemonte E., Fondamenti di Scienza dei Polimeri, Pacini Editore. Young R. J., Lovell P. A., Introduction to Polymers, CRC Press. Flory P. J., Principles of Polymer Chemistry, Cornell University Press

Class attendance is optional. The attendance of laboratory exercises is mandatory.

The written exam will include open-ended questions and a numerical exercise

The lessons will be delivered in the classroom, using conventional methods, employing computer support and slides. Practical exercises will be carried out in the laboratory. After the experimental activity, students are required to prepare a report to be submitted to the teacher before the exam.