高分子化学(浙江大学) polymer1 Introduction

repeating unit
重复单元
The degree of polymerization (DP) in a polymer molecule is the number, n, of repeating units in the polymer chain.
Mw DP mrepeautinnigt
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Synthetic rubber, elastomer (合成橡胶和弹性体)
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Synthetic fibers(合成纤维)
Kevlar Vest
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Fine polymers(精细高分子)
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Functional polymers(功能高分子)
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Plastics vs Steel
* China
1970 27 4.9 5.5 38
1980 53 12 13 78
1990 107 24 23 154
2000 175(11*) 35 (6.4) 44 (0.9) 254
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General Plastics(通用塑料)
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Engineering plastics(工程塑料)
• The repeat units can all be identical, in which case the compound is a homopolymer(均聚物).
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• If the repeat units are different, the result is a copolymer(共聚物). Consider a copolymer made from just two ingredients: the two can be sequenced along the backbone in various modes.
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Polymer(聚合物) vs Macromolecule(大分子)
Macromolecule
Polymer
molecule with high molecule weight molecule comprised of repeating unit
Sample
Polyethylene DNA Protein
polymer macromolecule
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1.2 Flowchart of Polymeric Materials
Inorganic • Natural
– Clays • Bricks • Cement • Pottery
– Sands • Glass
• Synthetic
– Fibers
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Industry Polymer
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Plastics Fibers Rubbers Coatings Adhensives Functional
General Fine
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B. Processability
结晶
无定形
Molecules in a thermoplastic (热塑性）are held together by relatively weak intermolecular forces, so that the material softens when exposed to heat and then returns to its original condition when cooled
交替
嵌段 无规
接枝
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• The chain itself can have many different topologies
线型 支化
环状 macrocycle
交联
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dendrimer 树枝状27
1.4 Production of polymer
• Nature
– precise control on molecular structure Starch, Natural rubber, Polysaccharides（多糖）
• Element polymer– no carbon in backbone
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1. Fundamental Concepts
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1.1 What is a polymer?
A polymer is a large molecule comprised of repeating structural units joined by covalently bonds.
(Hermann .Staudinger,1924)
A thermosetting(热固性) plastic, or thermoset, solidifies or "sets" irreversibly when heated.
Elastomers(弹性体) are rubbery polymers that can be stretched easily to
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Polymers are large molecules. Fortunately, they are not random collections of atoms; if this were the case, they would be impossible to study.
Polymers are built up from smaller molecules (monomers), and therefore possess a characteristic chain structure consisting of multiple repeat units that are related chemically
Note that all three representations are equivalent. One usually chooses the representation that emphasizes the monomer (单体) from which the polymer was made.
• Synthetic
– Various families and large quantities, but less precise
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1.5 Polymer Disciplines
Polymer science
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Polymer chemistry Polymer physics Polymer material Polymer process Polymerization engineering
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Energy Consumption
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Green or not?
Ideal material
polyolefin
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paper
glass
aluminium
23Biblioteka Baidu
1.3. Definitions
CH2CH n Cl
O
O
NH(CH2)6NHC(CH2)4C n
structural unit
结构单元
Reference Books
• 冯新德，《高分子合成化学》 化学工业出版社，1980。 • 林尚安 等，《高分子化学》科学出版社，2000。 • 赵德仁，张慰盛，《高聚物合成工艺学》化学工业出版社，
1997。
• Malcolm P. Stevens “Polymer Chemistry, an Introduction”, 3rd ed., Oxford University Press, 1999
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Polymer Chemistry
Content
• Polymer and its structure • Polymerization mechanism and kinetics • Polymer reaction
Frontier
• Novel synthetic method and polymer family • Design and control on the chain structure of polymer • Recycle of polymer
• The way people classify polymers depends their experience.
• Widely used historical terms or trade names lacking information content.
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A: Application
several times their unstretched length and which rapidly return to their
original dimensions whehn the applied stress is released.
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C: Chemical Composition
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Schedule
• Chapter 1 Introduction
3 hr
• Chapter 2 Radical Polymerization
12
• Chapter 3 Radical Copolymerization 6
• Chapter 4 Polymerization Process
3
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3
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2. Categories and Nomenclature of Polymer
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2.1 Classification Rules
• There is no uniform system of classification of polymers. The terminology has evolved along with polymer science, and there are numerous exceptions to categories.
• Carbon-chain polymer –backbone composed of carbon atom
CCCCC
• Hetero chain polymer –composed of both carbon and other atoms, e.g. O, N, S, P etc.
CCOCCO
Welcome to
Polymer Chemistry
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Content
• Polymer and its structure • Mechanism of polymerization reactions • Process of polymerization • The reactions of polymer
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In Nature
Cellulose, Starch, DNA, Protein
甲壳素 壳聚糖
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Synthetic Materials
Annual Production of Polymer Materials (million ton)
Year Plastics Synthetic fiber Synthetic rubber Total
There are end groups on the chain that are different from the repeat units, but these usually represent a negligible portion of the molecule, so they are seldom drawn.
• George Odian, “Principles of Polymerization”, 2nd ed., John Wiley &Sons, Inc., New York, 1981.
• http://jpkc.zju.edu.cn/k/511/
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Chapter I
Introduction
Organic • Natural
– Polysaccharides
– Proteins – Polyisoprene • Synthetic – Plastics – Fibers – Rubbers – Adhesive – Coatings –…
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Polymer is everywhere
Poly comes from the Greek word for "many" and mer comes from the Greek word for "parts“.
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methane
gasoline
wax
polyethylene
carbon
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degree of polymerization 聚合度