Metal materials and human civilization
From the mysterious shape memory alloy to the star of future energy materials-hydrogen storage alloy
Ancient ceramics-a new look for the old.
From the ancient kingdom of materials to the glory of modern inorganic materials.
Powerful advanced structural ceramics to wonderful functional ceramics.
Young polymer materials-various forms
The New Kingdom of Materials in the 20th Century —— Polymer Materials in Modern Life
Functional polymers show their magical power.
Advanced composite materials-wonderful technology
New functional materials-the ladder of human civilization and progress
Biological materials, information materials, environmental materials, nano materials, energy materials and intelligent materials.
Materials-the cornerstone of civilized architecture in human society
Several active fields of materials science and technology
1. biomaterials: including biomedical materials and bionic materials.
2. Smart materials: such as piezoelectric ceramics and shape memory alloys.
3. Environmental materials; 4. Nanomaterials
5. Functional polymer materials: water-absorbing polymer, conductive polymer, luminescent organic polymer, polymer shape memory, polymer electrolyte, polymer piezoelectric, organic nonlinear optical material, degradable polymer and polymer liquid crystal, etc.
6. Computer simulation and material design: Computer simulation is used to predict the structure and properties of materials and their relationship, so as to realize material design and form "Computational Materials Science".
Polymer science is not only an applied discipline, but also a basic discipline. It is a new discipline that has gradually developed on the basis of organic chemistry, physical chemistry, biochemistry, physics and mechanics.
polymer science
high polymer chemistry
Study the principle of polymerization and polymer chemical reaction, select raw materials, determine the route, find catalysts, and formulate the synthesis process.
Studying the relationship between the structure and properties of polymers provides theoretical guidance for the design and synthesis of polymers with predetermined properties, and is a bridge between synthesis and application.
Polymer physics
Polymer processing
The principle and technology of polymer processing and molding are studied.
polymer science
L 1839 Goodyear invented the vulcanization of natural rubber.
In l 1855, celluloid plastic (nitrocellulose+camphor) was manufactured by parks company in England.
The Frenchman de Scialdone invented rayon.
The formation of the concept of polymer and the emergence of polymer science began in the 1920s.
L 1920, German staudinger published his epoch-making document "On Aggregation" and put forward the concept of high molecular long chain structure.
I. Development of Polymer Science
1909 Baekeland synthetic phenolic resin
19 1 1 year, British Matthews synthesized polystyrene.
19 12 PVC was synthesized.
Polymethyl methacrylate was synthesized from 1927.
1933 high-pressure polyethylene came out.
1938 tetrafluoroethylene is polymerized …
Ziegler synthesized polyethylene at low pressure of 1953, and then synthesized polypropylene with nata. Ziegler and Natta won the Nobel Prize in chemistry.
The miracle of polymerization
The discovery of plastics
1869 3 1 year-old printer John Hayat invented celluloid.
Baekeland invented phenolic resin.
Polymer materials in modern life-plastics
Polymer materials in modern life-engineering plastics
Development of rubber
Tears of the oak tree
Ugly but popular synthetic rubber
Polymer material in modern life-rubber
1855, Otimas, Switzerland, put cellulose into nitric acid to obtain nitrocellulose solution, and made the first man-made fiber.
1884 put nitrocellulose into ethanol and ether to get a solution, and get rayon;
Development of fiber
Development of Functional Polymer Materials
Functional polymer materials began to develop in the late 1960s.
Functional polymers refer to polymers and their composites with chemical reactivity, catalysis, photosensitivity, conductivity, magnetism, biocompatibility, pharmacology and selectivity, or with the function of transforming or storing substances, energy and information.
At present, the functional polymers that have reached practical use include ion exchange resin, separation functional membrane, photoresist, photosensitive resin, polymer sustained-release drugs, artificial organs and so on.
Functional polymer materials such as polymer sensitive elements, highly conductive polymers, high-resolution separation membranes, highly photosensitive polymers and polymer solar cells are about to enter the practical stage.
Functional polymer material-super absorbent resin
Super absorbent resin is a kind of functional polymer material, which has excellent water absorption and water retention functions and can absorb hundreds or thousands of times its own weight, so it is called "super absorbent".
The main types are polyacrylate, polyvinyl alcohol, vinyl acetate polymer, polyurethane, starch graft polymer and so on. Polyacrylate is made of acrylic acid and caustic soda by reverse polymerization.
Can be made into feminine sanitary napkins, baby diapers, napkins, etc. In addition, it can also be used as indoor air fragrance, preservative for vegetables and fruits, mildew inhibitor, flame retardant, moisture-proof agent and children's toys that swell after absorbing water.
At present, the global total production capacity has exceeded 6.5438+0.3 million tons/year, among which Japan Catalyst Chemical Company is the largest production company in the world with a production capacity of 250,000 tons/year.
Polymer membrane refers to a membrane made of polymer materials with special separation function, which can selectively separate substances. At present, they are used in seawater desalination, reverse osmosis, membrane extraction, membrane distillation and other technical fields.
Polymer separation membrane
Kita Water Plant, built in Saudi Arabia, is the largest seawater desalination plant in the world, supplying fresh water 12000 tons per day, mainly using cellulose acetate separation membrane device.
Photosensitive polymer materials represented by photosensitive resin are mainly used in photography, printing plate making and printed integrated circuits.
Polyvinyl alcohol ester is used in printing industry, which is cross-linked but insoluble under illumination and remains to obtain relief.
Photolysis photoresist, diazoquinone is attached to phenolic resin, and the image is saved under the action of light, and the resolution is 10 nm.
Photosensitive polymer material
1950, people began to wear contact lenses made of polymethyl methacrylate (PMMA), which has excellent optical properties and can correct corneal astigmatism. 1960, Czech scholars invented the material of soft contact lenses in ten years, that is, 2- hydroxyethyl methacrylate (HEMA), which has been used ever since.
Functional polymer material-contact lens
Light-emitting plastics can be made by adding light-storing luminescent materials into plastics. Luminous plastics are new functional materials with high added value in recent years. Its products are: lane sign, stair sign, sign line; Luminous paint, luminous opening, luminous wallpaper, handicrafts, toys, sports and leisure products.
Functional polymer material-luminescent material
Since the discovery of conductive polymers, it has become a research hotspot in materials science. At present, it has become a new interdisciplinary research field, attracting a large number of material design experts from all over the world.
Functional polymer material-conductive polymer material
As a new type of high-performance material, liquid crystal polymer has attracted great attention from science and industry, and has been widely used, and has developed into one of the most active fields in polymer science.
Liquid crystal polymer
Bamboo floor
Carpets can be made of durable wool products or pet carpets.
Waterborne coatings, powder coatings and radiation curing coatings are mainly used.
Outdoor landscape products: benches, tables and traffic signs made of recyclable plastic.
green building materials
Biodegradable polymer materials
At present, there are "white" (plastic) and "black" (rubber) wastes in nature. It is necessary and urgent to develop biodegradable products, but many specific problems cannot be solved.
1, the bearing capacity of degradable plastic bags is low; 2. Degradable plastic bags are dim and yellow with low transparency; 3. The price is high and the cost is unacceptable.
Disposable medical supplies, such as infusion tubes, medicine bottles and medical adhesives. Diagnostic instruments, such as rash detectors, endoscopes and various other diagnostic instruments.
External devices, such as artificial limbs, hemodialysis or perfusion devices.
Human organs such as heart catheter, heart patch, artificial heart pump material, tracheal catheter, artificial bladder, artificial meninges, arterial patch, artificial blood vessels and artificial joints.
Plastic surgery materials such as facial plastic implants.
Biodegradable materials refer to those materials that can be decomposed by body fluids, enzymes or microorganisms, and are used for sutures, human implants, controlled-release drugs and so on.
Types of medical polymer materials
artificial heart
biological materials
joint prosthesis
artificial kidney
Unique composite material
Carbon fiber composite material
FRP composite material
So far, the winner of the Nobel Prize in Polymer Science.
H. staudinger (Germany): The concept of "polymer" was introduced into the scientific field, and the relationship between viscosity and molecular weight of polymer solution was established (1953 Nobel Prize).
K Ziegler (Germany), G Natta (Italy): Coordination Polymerization of Ethylene and Propylene (1963 Nobel Prize)
Page (abbreviation of page) J. Flory (USA): polymerization principle, the relationship between physical properties and structure of polymers (1974 Nobel Prize).
H. Hideki Shirakawa Shirakawa (Japan), Alan G. MacDiarmid (USA) and Alan J. Heeger (USA): Discovery and development of conductive polymers (Nobel Prize in 2000).
De Gennis (France): Soft matter, universality, scale, magic ladder.
2. Scientific development of polymers in China.
L China's polymer research began in the early 1950s, and Tang Aoqing published the first polymer science paper on 195 1.
L Changchun Huaying Research Institute 1950 started to work on synthetic rubber (Wang Fosong, Shen Zhiquan);
L Feng Xinde set up the specialty of polymer chemistry in Peking University in 1950s.
In the mid-1950s, Lin Bing studied ion exchange resin in Nankai University.
On 1952, Qian Renyuan set up a polymer physics research group in Huaying College to study the properties of polymer solutions.
As early as 1950s, Qian began to study the viscoelasticity and radiation chemistry of polymers in the institute.
At the beginning of 50, Mr. Xu Biao began to study plastic engineering in Chengdu University of Technology (Sichuan University).
L Mr. Wang Baoren 1952 Shanghai Institute of Organic Sciences established PMMA and PA6 research groups.
China and Academician of Chinese Academy of Sciences in Polymer Field: Wang Baoren, Feng Xinde, He, Qian, Qian Renyuan, Yu Tongyin, Wei Xu, Wang Fosong, Cheng Rongshi, Huang, Zhuo, An, Shen Zhiquan, Bai Chunli, Zhou Qifeng, Cao Yong, Yang Yuliang, etc.
2 1 century polymer science
In human history, almost no science and technology has made such a great contribution to human society as polymer science. 2 1 At the beginning of the century, polymer science and its related technologies are facing new opportunities and challenges.
Some areas facing opportunities and challenges:
1. Catalytic process and new polymerization method
2. Nonlinear structural polymers
3. Supramolecular assembly and highly self-organized macromolecules
4. Polymer crystallization and morphological engineering
5. Stimulation-responsive polymers
6. Recovery and treatment of polymers
Development direction of polymer materials
1. High performance
2. High functionality
Step 3 synthesize
Step 4 refine
Become smart
We should pay attention to learning, interdisciplinary, independent thinking and independent innovation, solve academic problems in production practice, improve the academic level of polymer science, and serve the development of national economy.
From the development of the above materials, we can see that scientific development is endless, and temporary satisfaction and contentment with the status quo will lead to backwardness, continuous progress and innovation.
Human demand is the driving force to promote scientific development
The teaching content of polymer physics is to reveal the internal relations and basic laws between the structure and properties of polymer materials.
Polymer structure is the basis of polymer performance, and performance is the reflection of polymer structure, and the molecular movement of polymer is the bridge between structure and performance. That is to say, through the understanding of molecular movement, the internal relationship between structure and performance can be established, and the relationship between structure and performance can be mastered. Through synthesis, modification and processing, the performance of polymers can be improved to meet the needs, which lays a scientific foundation for molecular design and material design of polymers and provides theoretical basis for synthesis, processing, molding, testing and application of polymer materials.
Second, the teaching content of polymer physics
Chain structure of polymer
Coalescent structure of polymer
Polymer solution
Molecular weight and molecular weight distribution
Transformation and relaxation of polymers
Rubber elasticity
Viscoelasticity of polymer
Yield and fracture of polymers
Rheological properties of polymers
Other characteristics of polymers
Second, the teaching content of polymer physics
Polymer structure: including polymer chain structure and condensed structure, segment, flexibility, spherulite, platelet, molecular weight and molecular weight distribution, and the concept of θ solution.
Properties of polymer materials: mechanical properties, thermal, electrical, optical and magnetic properties. Mechanical properties include tensile properties, impact properties, cracking, shear band, strength and modulus.
Molecular motion of polymers: glass transition, viscoelasticity, entropy elasticity, crystallization kinetics, crystallization thermodynamics, melting point, rheological properties, viscosity, non-Newtonian fluid.
WLF equation, Avrami equation, rubber state equation, Boltzmann superposition principle.
Main contents of polymer physics
Relationship between polymer structure and properties
How to study methods
Structure: long chain, elasticity, entanglement, fragment movement
Properties: light weight, easy coloring, good toughness, corrosion resistance,
Easy processing, shock absorption, biocompatibility and easy tailoring.
Why is the purpose of the study?
Guide macromolecular design
Guided machining
Developing polymer materials
1. Characteristics of polymer structure (compared with small molecules)
① Chain structure of polymer: polymer consists of a large number of structural units (103- 105).
② Flexibility of polymer chain: The internal rotation of polymer chain produces many conformations (such as PE with DP= 100, and the number of conformations is 1094), which can bend the main chain and make it flexible.
③ The polymer structure has polydispersity and heterogeneity.
④ Complexity of polymer condensed structure: crystalline, amorphous, spherulite, tandem, single crystal, linear crystal, etc. Its condensed structure has great influence on the physical properties of polymer materials.
Polymer materials (plastic, rubber, fiber) have the following advantages:
① Light weight and low relative density. Low density polyethylene (0.9 1), polytetrafluoroethylene (2.2)
② Good electrical performance and insulation performance.
③ Excellent thermal insulation performance and thermal insulation materials.
Good chemical stability and chemical solvent resistance.
Good wear resistance and fatigue resistance. Rubber is an irreplaceable material for tires.
Good self-lubrication, used for bearings and gears.
⑦ Good light transmittance. Resin optical disc, resin lens.
⑧ Wide mechanical selectivity.
Pet-name ruby has wide sources of raw materials, convenient processing and molding, suitable for mass production and low cost.
Attending beautifully decorated. You can color and decorate at will.
2. Performance characteristics of polymer materials
Nature and use
plastic
Xianwei
Rubber rubber
coating
agglutinant
functional polymer
Polymer-based plastics or rigid materials, with or without additives and fillers.
High elastic material with reversible deformation.
Fine and soft silk, the length is at least 100 times the diameter.
A polymer material coated on an object to form a tough film, which plays a decorative and protective role.
A polymer material that can connect two or more objects together by bonding.
Fine polymer materials with special functions and uses but little dosage.
3. Application of polymer materials
Agricultural plastics: ① film ② irrigation pipe
Construction industry: ① PVC for water supply and drainage pipelines, HDPE for plastic doors and windows, ③ paints and coatings.
④ Composite floor, furniture and artificial wood, floor ⑤PVC ceiling.
Packaging industry: ① plastic film: PE, PP, PS, PET, PA, etc.
② Hollow containers: PET, PE, PP, etc.
③ Foam plastics: PE, PU, etc.
Automobile industry: plastic parts, instrument panels, insurance machines, fuel tank interiors, cushions, etc.
Military industry: solid fuels (oligomers) and composite fibers for aircraft and rockets.
3. Application of polymer materials
Polymer materials are widely used in all walks of life, including packaging, agriculture, forestry, animal husbandry and fishery, construction, electronics and electricity, transportation, household daily use, machinery, chemicals, textiles, medical care, toys, cultural and educational offices, furniture and so on.
Electrical industry: ① insulating materials (thermal conductivity and resistivity), conductive polymers, etc.
Electronic category: communication optical fiber, cable, wire, CD-ROM, mobile phone and telephone.
③ Household appliances: shell, inner container (TV, computer, air conditioner), etc.
Medical and health applications: artificial heart, artificial organ, artificial kidney (PU),
Keywords artificial muscle, infusion tube, blood bag, syringe,
Soluble suture, drug release, etc.
Anti-corrosion engineering: anti-corrosion and anti-corrosion structural materials, such as PTFE;
Working at 230 ~ 260℃ for a long time, suitable for products with high temperature and serious corrosion.
Functional polymer: ion exchange resin, polymer separation membrane, super absorbent resin,
Keywords photoresist, photosensitive resin, medical polymer, liquid crystal polymer,
Highly conductive polymer, electroluminescent polymer, etc.
3. Application of polymer materials
4. Knowledge of polymer physics to solve practical production problems.
① Molecular weight and molecular weight distribution affect the properties of polymer materials:
High molecular weight: the material has high strength, but poor processing fluidity and moderate molecular weight.
Molecular weight distribution: A fiber, narrow distribution, high molecular weight components are not good for strength performance.
B rubber: the average molecular weight is large and the processing is difficult. Therefore, after plasticization, the molecular weight is reduced and the distribution is widened, which plays a plasticizing role.
② The condensed structure affects the properties of polymer materials;
Crystallization makes materials strong, brittle and tough.
In addition, the spherulite size also affects the performance, and the spherulite should not be too large.
Nucleating agent can be added to reduce the spherulite size; Change the crystallization temperature, more nucleation.
③ Processing technology affects the properties of polymer materials:
Low viscosity and easy processing. Polycarbonate, change temperature, reduce viscosity. Polyethylene: change screw speed, increase injection pressure and shear force → reduce viscosity.
5. How to learn polymer physics well
Polymer physics has many contents, concepts, clues, relationships and mathematical deduction. Grasping the main line of the relationship between polymer structure and properties, taking molecular motion and thermal transformation as a bridge to link the relationship between structure and properties, and integrating scattered knowledge into one.
Listen carefully in class, pay attention to concepts, methods and sum up the rules.
We should pay attention to cultivating self-study ability, read carefully after class, think independently, and deduce examples and exercises by ourselves.
Heuristic teaching method abolished the previous injection teaching method.
[1] He Manjun, Chen, Dong Xixia, Polymer Physics, Shanghai, Fudan University Press, 1990.
[2] Ma Dezhu, He Yongsheng, etc. Structure and properties of polymers, Beijing, Science Press, 1995.
[3]B.Wunderlich, Macromolecular Physics, Academic Press, new york, 1973.
[4]P. J. Flory, Principles of Polymer Chemistry, Cornell University. News, new york, 1953.
[5] Degenes P.G., Scaling Concept in Polymer Physics, Cornell University. News, new york, 1979.
Strobl, Polymer Physics, springer Publishing House, 1996.
Good luck! !