88. 11 Solutions of macromolecules
§8.11 Solutions of macromolecules
8.11.1 Macromolecules and their solutions 1. Lyophilic sol and macromolecules Lyophilic sol (1)Spontaneous dissolution/dispersion (2)thermodynamically stable ()Weak Tyndall effect (4)High viscosity Hermann Staudinger Mar:.23,1881-Sep.8,1965 German organic chemist 1953 Nobel prize The existence of macromolecules https://en.wikipediaorg/wiki/hermann_staudiNger
Hermann Staudinger Mar. 23, 1881-Sep. 8, 1965 German organic chemist 1953 Nobel Prize The existence of macromolecules https://en.wikipedia.org/wiki/Hermann_Staudinger 1. Lyophilic sol and macromolecules Lyophilic sol (1) Spontaneous dissolution/dispersion; (2) thermodynamically stable; (3) Weak Tyndall effect; (4) High viscosity. 8.11.1 Macromolecules and their solutions
8.11.1 Macromolecules and their solutions 2. Definition of macromolecules Macromolecules: a chain-like molecule with its molar mass higher than 10000 Natural macromolecules: protein, starch, cellulose Artificial macromolecules: PE, PP, PS, nylon-66
Macromolecules: a chain-like molecule with its molar mass higher than 10000. Natural macromolecules: protein, starch, cellulose; Artificial macromolecules: PE, PP, PS, nylon-66 8.11.1 Macromolecules and their solutions 2. Definition of macromolecules
8.11.2 Viscosity of macromolecular solutions 2. 1 viscosity of macromolecule solutions Newtonian viscosity law: F=nA Relative viscosity Specific -7 7n ty 7 Reduced 7p7 vIscoSity C C Intrinsic VIScOSIty C→)0 C c is concentration in g/l
Newtonian viscosity law: dx du F =A Relative viscosity Specific viscosity Reduced viscosity Intrinsic viscosity 0 r = r 1 0 0 sp = − − = c c sp r −1 = c c sp 0 lim → = c is concentration in g/ml 8.11.2 Viscosity of macromolecular solutions 2.1 viscosity of macromolecule solutions
8.11.2 Viscosity of macromolecular solutions 2. 1 viscosity of macromolecule solutions Reptation Theory Relationship between intrinsic viscosity and molar mass of macromolecule Slope 3.4 SP M For spherical molecule: a=0 For rod-like molecule. a=2 For flexible thread-like molecule a=0.5-1.0 In good solvent: a>0.5; in bad solvent: as KM 0.5
= KM Relationship between intrinsic viscosity and molar mass of macromolecule For spherical molecule: = 0 For rod-like molecule: = 2 For flexible thread-like molecule: = 0.5~1.0 In good solvent: > 0.5; in bad solvent: 0.5 8.11.2 Viscosity of macromolecular solutions 2.1 viscosity of macromolecule solutions