复旦_高物课件chapter5课件.pptVIP

Chapter 5 Condensed States of Polymers;5.1 Polymer Melts and Glasses;Glass Transition as a Relaxation Process;5.2 Polymer Crystallization;5.2.1 Chain Conformations in Crystals;Why Helix ?; Chain packing in crystal lattices; Chain packing in crystal lattices;;;5.2.2 Basic Morphology of Polymer Crystals;Lamellae Crystallized from Dilute Solution;Orientations of polymer chains in lamellae; Polyoxymethylene (聚甲醛);;Lamellae Crystallized from Melt; Lamellae in a spherulite;蛙畅坞椿抓丛催嘴碱炳确摩遍茵祭任锅神吭畦谢反希庐获篱茁舷触昌栈洲复旦_高物课件chapter5课件复旦_高物课件chapter5课件;The mechanism of Maltese cross extinction pattern;Theoretical analysis of Maltese cross extinction pattern;Relations of POM and SALS (small angle light scattering);SALS patterns of spherulites;5.2.3 Polymer Crystallization;;Chain-Folded Lamellae of Polymers;Process of Polymer CrystallizationTwo steps:;Estimate the critical nucleus size;2. Linear Growth of Polymer Crystallization;Overall Polymer Crystallization Rate;Overall Crystallization Kinetics;Kinetics models of overall crystallization;Poisson’s raindrop problem If raindrops fall randomly on a pond creating expanding circular waves, what is the chance that the number of waves created by different raindrops which pass over a representative point P up to time t is exactly n?;Thermodynamics of Crystallization: 1. Melting point of Lamellar Crystals;Thermodynamics of Crystallization: 1. Melting point of Lamellar Crystals;Thermodynamics of Crystallization: 2. Melting point of Polymer mixture;Effects of “Impurities” on Tm;Effects of “Impurities” on Tm;3. Effects of Chain Structure on Tm;5.3 Oriented States of Polymers;5.4 Liquid Crystalline Polymers;What are Liquid Crystals;Nematic Phase (向列相) ;Smectic Phases (近晶相);Liquid Crystal Phase of Chiral Molecules;Lyotropic liquid crystals: 1) surfactants or amphiphilic block copolymers;Lyotropic liquid crystals:2) rigid-rod polymers;POM Used in the Study of LC Phases;POM Used in the Study of LC Phases;Liquid Crystalline Polymers; Thermodyna