第十章聚合物材料的力学性能（Chapter mechanical properties of polymer materials）.doc

第十章聚合物材料的力学性能（Chapter 10 mechanical properties of polymer materials） Chapter 10 mechanical properties of polymer materials § 10-1 the structure and performance characteristics of polymer materials Organic compounds with more than 10, 000 molecules are called polymer materials, which are polymerized by many small molecules, known as polymers or polymers. The atoms are bonded together by a covalent bond, which is called the primary valence bond; The molecules are connected by the van der waal bond, called the subvalence bond. The sum of the intermolecular valence bonds is far greater than the binding force between the atoms in the molecule. When you stretch, you usually break the atomic bonds first. Small molecular compounds of polymers are called monomers, and the basic structural units that make up polymer long chains are called chains. The number of repeats of the polymer long chain is called polymerization degree. Natural polymers include wood, rubber, cotton, silk, hair and horns. Synthetic polymers include engineering plastics, synthetic fibers, synthetic rubber, etc The basic structure of a polymer 1. Configuration of polymer chain (short range structure) The geometrical shape fixed by chemical bonds refers to the chemical composition, bonding mode and stereoconfiguration of the polymer chain. As shown in figure 9-1. (FIG. 9-2). Long branched chain, short branched chain; Linear crosslinked molecular chain, three-dimensional crosslinked molecular chain. A polymer consisting of two or more structural monomers is called a copolymer. The crystallization of the polymer is difficult to complete. (several forms of copolymer are shown in figure 9-3.) 2. Conformation of polymer chain (remote structure) The image of a large molecular chain in space, called the conformation of a giant chain. No regular linear chain, stretching chain, folding chain, spiral chain and other conformations (FIG. 9-5). 3. Polymer aggregation structure The aggregation structure includes crystall