This document discusses polymers, including their definition, classification, examples, and important types. It begins by defining polymers as giant macromolecules made from repeating monomer units. Polymers can be classified in several ways, including by origin (natural, semisynthetic, synthetic), structure (linear, branched, cross-linked), and molecular forces. Examples of important polymers discussed include natural rubber, polyethene, teflon, nylon, polyester, bakelite, and biodegradable PHBV. Key properties and uses of these polymers are also provided.
The presentation gives a brief idea about polymers,its definition,types of polymers,common examples of polymers,polymerization and its types,polymer processing and applications of polymers.
The presentation gives a brief idea about polymers,its definition,types of polymers,common examples of polymers,polymerization and its types,polymer processing and applications of polymers.
It is described about polymer/clay nanocomposites which can be abbreviated to PCNC, their preparation methods, properties and relevances, important types of polymers employed in the preparation of PCNC, montmorillonite crystal structures,
It is described about polymer/clay nanocomposites which can be abbreviated to PCNC, their preparation methods, properties and relevances, important types of polymers employed in the preparation of PCNC, montmorillonite crystal structures,
Polymers play a very important role in human life. Our body is made of lot of polymers, e.g. Proteins, enzymes, etc. Other naturally occurring polymers like wood, rubber, leather and silk are have wide application. Now a day synthetic polymer like useful plastics, rubbers and fiber materials are synthesized. presentation includes introduction classification and preparation methods. Polymers play a very important role in human life. Our body is made of lot of polymers, e.g. Proteins, enzymes, etc. Other naturally occurring polymers like wood, rubber, leather and silk are have wide application. Now a day synthetic polymer like useful plastics, rubbers and fiber materials are synthesized. Leo Baekeland patented the first totally synthetic polymer called Bakelite (1910). Bakelite is a versatile, durable material prepared from low-cost materials phenol and formaldehyde and was the most important synthetic polymer material. In the 1920s Hermann Staudinger showed that polymers were high-molecular-weight compounds held together by normal covalent bonds.
The suffix in polymer ‘mer’ is originated from Greek word meros – which means part. The word polymer is thus coined to mean material consisting of many parts or mers. A macromolecule having high molecular mass (103-107u) and generally not a well-defined structure or molecular weight. The macromolecules formed by joining of repeating structural units on a large scale. The repeating structural units are simple and reactive molecules linked to each other by covalent bonds. This process of formation of polymers from respective monomers is called polymerization. Most of the polymers are basically organic compounds, however they can be inorganic (e.g. silicones based on Si-O network).
Polymer science revolves around the study of macromolecules known as polymers, which are formed by linking together repeating units called monomers. Understanding the relationship between polymers and monomers is fundamental to grasping the diverse properties and applications of these materials.
Additionally, we'll delve into the nomenclature of polymers, which involves the systematic naming conventions used to describe their structure and composition. Clear and standardized nomenclature ensures effective communication within the scientific community and facilitates the classification of polymers based on their chemical structure, properties, and applications.
Types of fibres,their classification,applications,properties, and structures
Further more polymers,their types and different type chemical bonds present in fibres,
Methods of polymerisation It is also called as Zeigler – Natta polymerisation.
Zeigler (1953) and Natta (1955) discovered that in the presence of a combination of transition metal halides like TCl4, ZnBr3 etc, with an organometallic compound like triethyl-aluminium or trimethyl-aluminium, stereospecific polymerisation can be carried out.
Combination of metal halides and organometallic compounds are called Zeigler Natta catalyst.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
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Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
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The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
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The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
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Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
TESDA TM1 REVIEWER FOR NATIONAL ASSESSMENT WRITTEN AND ORAL QUESTIONS WITH A...
Polymers
1. • Definition and Introduction.
• Types of polymers.
• Examples ; structures, formations, uses
• Degree of polymerization and molecular mass.
- Ms. Anshika Verma,
- M.Sc (Chem), M.Sc (Biotech), B.Ed,
2. INTRODUCTION
• Definition: polymers are complexes, giant macromolecules made from
the repeating units which are derived from small molecules called
“monomers”
• Derived from Greek word “poly” meaning many and ‘mer’ meaning
part or unit.
• The smallest unit of a polymer which is capable of forming at least two
bonds with others is called ‘monomer’
• Examples???
3. Classification of polymers.
1. Based on origin.
2. Based on structure.
3. Based on mode of polymerization.
4. Based on intermolecular forces.
5. Based on no. of monomers.
6. Based on biodegradability.
4. Classification based on source:-
• On the basis of sources of polymers they are classified in three types.
a)Natural polymers –
•Polymers either obtained from plants or animal are called natural polymers.
They are called plant and animal polymers.
a) Plant polymers: derived from pant sources.
Ex. Cellulose, Jute, Natural rubber
Natural
rubber
b) Animal
polymers: derived
from animal
sources.
Ex. Wool, silk, etc.
5. b) Semisynthetic polymers –
• The polymers obtained by simple chemical
treatment of natural fibers to improve
their physical properties like lustrous nature,
tensile strength are called semisynthetic fibers
• Used in preparation of non-inflamable
photographic films, cinema films, varnishes,
etc.
• Ex. Acetate rayon, cupraammonium silk,
viscous rayon, cellulose acetate (acetate
rayon)
6. c) Synthetic fibers-
•The fibers obtained by polymerization of simple chemical
molecules in laboratory are synthetic fibers.
•Artificially prepared by polymerization of one monomer or co
polymerization of two or more monomers.
•Ex. Nylon, terylene, polyethene, polystyrene, synthetic rubber,
nylon, pvc, bakelite, teflon etc.
•Further classified as fibers, synthetic rubbers and plastics.
7. Classification based on the structure of polymers :-
• On the basis of structure they are classified in three types –
a) Linear polymers –
• In these polymers monomers are linked with each other and form a
long straight chain.
• Formed by linking of bifunctional monomers or alkenes.
• These chains has no any side chains.
Ex. Polyethene (HDPE) , PVC, etc.
.
8. b) Branched polymers –
• They have a straigh long chain with different side
chains.
•Monomers are having 3 functional groups of already
having side chains
Ex. polypropylene (sidechain —CH3), polyethene
(LDPE).
9. c) Network or cross linked polymers –
• In these monomeric units are linked together to constitute a 3-D
network.
•The links involved are called cross links.
•They are hard, rigid .and brittle due to their network structure.
Ex. Bakelite, melamine, formaldehyde resins, vulcanised rubber etc.
Urea-Formaldehyde resin
Bakelite
10. •Classification based on
polymerization process :-
On this basis they are classified in two types
A) Addition polymers –
• The polymers formed by the addition
of monomers repeatedly without
removal of by products are called
addition polymers.
• These polymers contains all the atoms
of monomers hence they are integral
multiple of monomer unit.
• The monomeric units are generally
alkenes and its derivatives
• Ex. Orlon, teflon, polyethene,
polypropylene, PVC.
.
ORLON: ARTIFICIAL WOOL
11. B) Condensation polymers –
• They are formed by the combination of two
monomers by removal of small molecules like water,
alcohol or NH3.
• They have ester and amide linkage in their
molecules.
• Their molecular mass is not the integral multiple of
monomer units.
• Chain growth occurs by series of condensation steps.
Hence it is also refered as step growth
polymerization.
• Ex. Polyamides (Nylons), polyesters.
12. C) Ring opening polymers –
• Lactams, cyclic ethers, lactones polymerize by ring opening.
• Similar to addition polymerization. However in addition
polymers, the monomer is repeatedly added, however in ring
opening the cyclic structure is opened.
• Also a step growth polymerization like condensation
polymerization.
13. Classification based on molecular forces :-
•Mechanical properties of polymers like tensile strength, toughness, elasticity
depends upon intermolecular forces like van-der waals forces and hydrogen
bonding.
A) Elastomers –
• As the stain is applied polymer get stretched and as the force is released
polymer regain its original position
• These are the polymers in which polymer chains are held up by weakest
attractive forces. The cross linking avoids tearing of the polymer.
• These polymers are elastic and called elastomers.
Ex. Neoprene, vulcanised rubber, Buna-S, Buna -N.
14. B) Fibers-
• They have high intermolecular
attractive force like H-bonding and
crystalline in nature.
•They have high tensile strength and
used in textile industries.
• Ex. Nylon-6, Nylon-66, Terylene.
Nylon examples:
Terylene examples:
15. 3) Thermoplastic and
4)Thermosetting plastics
Thermoplastics
1. They become soft on heating
and hard on cooling.
2. Can be recycled, reused.
3. Can be remolded.
4. Generally linear and
branched polymers
5. Undergo addition
polymerization.
6. Ex. PVC, polyethene, PAN,
polystyrene, PP, etc.
Thermosetting plastics
1. They do not become soft on
heating
2. Cannot
3. Cannot
4. Generally cross linking/network
polymers.
5. Undergo condensation
polymerization.
6. Ex. Nylons, Terylene, Bakelite,
etc.
16. •Classification based on NO.
OF MONOMERS involved in
the polymer:-
1)Homopolymer-
• These are composed of ONLY one
type of monomer.
Ex. Polyethene, PVC, PP, Polypropylene,
2) Heteropolymer-
These are composed of more than one
type of monoomer.
These are called co-polymers.
Ex. Nylon, Buna – N, Buna-S, Terylene,
etc.
17. Classification based on
degradability:
1. Non- Biodegradable
polymers.
• Not affected by micro organisms.
• Accumulate in the environment for long
time and cause pollution hazards.
• Ex. Polythene, polystyrene, etc.
2. Biodegradable polymers.
• Degraded by microbes.
• Environment friendly.
• Ex. PHBV, Nylon 2,6 , Dextran, etc.
18.
19. IMPORTANT POLYMERS:
1. NATURAL RUBBER.
• Monomer: Isoprene ( 2- methyl buta-
1,3-diene)
• Linear polymer of isoprene.
• Undergoes addition polymerization.
• Properties:
Has Cis configuration.
Exhibits elasticity.
• Trans isoprene is called “Gutta-
Percha” which is crystalline and non
elastic.
20.
21. VULCANIZATION OF RUBBER:
1. Process to improve the physical
properties of natural rubber (toughness,
elasticity, tensile strength, etc.)
2. Discovered by Charles Goodyear in
1839.
3. The process by which a network of
cross linking is introduced into the
elastomers is called vulcanization.
4. Generally Sulfur is used to form cross
linking resulting in improved properties.
5. More the % of S, harder will be the
rubber.
6. Ex. 1-3% sulfur: Rubber bands.
3-10% Sulfur: Tyres.
22. 2. POLYETHENE.
a) LDPE ( LOW DENSITY POLYETHENE).
• It is a branched polymer obtained by
polymerization of ethene under 1000-2000 atm
pressure and 350-570 K temperature in
presence of trances of O2/peroxide as initiator.
• Involves free radical mechanism.
• The terminal carbon atom of growing chain
abstracts a H atom to for a 2o free radical
resulting in the branching
• Properties:
Flexible but tough
Chemically inert
Low density and melting point ( 110oC)
Poor conductor of electricity.
• Uses:
Pipes, insulation in cables,
Packaging – squeeze bottles, containers,
etc.
23. b) HDPE (HIGH DENSITY
POLYETHENE).
• Linear polymer obtained by
polymerization of ethene under 6-7
atm pressure and 333-343 K
temperature in presence of
“Zieglar –Natta catalyst”
(combination of titanium
tetrachloride and triethyl aluminium)
• Properties:
High tensile strength.
High density and melting point
( 144 - 150oC)
More resistant to chemicals
and stiffer than LDPE.
• Uses:
Toys, buckets, dustbins,
bottles, pipes, etc.
24. 3. TEFLON (POLYTETRA FLURO
ETHYLENE):
• Monomer: Tetra fluro ethylene/ethene.
• Polymerization takes place using free radical
initiators such as hydrogen peroxide or
ammonium persulphate at high pressure.
• Properties:
Tough, chemically inert,
Resistant to heat.
Resistant to attack by
corrosive agents.
• Uses:
Making non stick cookware
Oil seals.
Gaskets, etc
25. 4. ORLON (POLYACRYLONITRILE/ PAN/ ACRILAN):
• Monomer: Acrylonitrile
• Prepared by polymerization of acrylonitrile using peroxide as initiator.
• Uses:
Artificial or substitute for wool.
CH2 = CH – CN
Acrylonitrile.
26. 5. POLYAMIDES:
• Obtained by condensation between
dicarboxylic acid and diamine.
a. NYLON 6,6
• Monomers: Adipic acid
hexamethylene diamine.
• Number 6, 6 denote two monomers each
having 6 carbon atoms.
• Properties:
Linear condensation polymer.
High tensile strength
Does not soak in water.
• Uses:
Making sheets
Bristles of brushes,
Surgical sutures,
Textile fabrics
Ropes, fishing nets, etc.
27. b. NYLON 6
• Monomer: έ – Caprolactum.
• Shows ring opening polymerization
• Number 6 represents a single monomer
having 6 carbon atoms..
• Properties:
High tensile strength
Luster.
• Uses:
Tyre cords.
Ropes
Fabrics
28. 6. POLYSTER ( TERYLENE/ PET/
DACRON
• Monomer: Ethylene glycol
Dimethyl Terepthalate (DMT)
• Obtained by condensation
polymerization between the monomers
at high temperature.
• Properties:
High M.P (265oC)
Resistant to chemicals and water.
• Uses:
Making wrinkle free fabrics
Blended with cotton: Terycot
Blended with wool: Terywool
PET: making bottles, containers,
etc.
29. 7. OTHER FORMALDEHYDE POLYMERS:
A.BAKELITE.
• Monomers: Phenol.
Formaldehyde.
• Monomers react in presence of acid or base catalyst to form thermosetting moulding
polymer “NOVOLAC” in two stages.
• In the third stage, novolac undergoes polymerization at high temperature of 138-
176oC and high pressure to form Bakelite. During this stage, crosslinks are formed
resulting in a rigid 3-D polymeric material i.e. Bakelite.
• Properties:
High tensile strength.
Insoluble and infusible.
• Uses:
Making telephonic instruments.
Kitchenware.
Electric insulators.
Handles of cookware.
Switches.
30.
31. B. FORMALDEHYDE – MELAMINE POLYMER.
• Monomers: Melamine
Formaldehyde.
• Condensation polymer.
• Used to make crockery.
32. 8. BUNA –S (SBR)
• Monomers: Styrene
Butadiene.
• Addition polymerization carried about by Na.
• Superior to natural rubber in terms of
abrasion resistance and mechanical strength.
Hence used in tyre making.
33. 9. NEOPRENE.
• Monomers: Chlroprene
(2- Chloro Buta -1,3- diene)
• Addition polymer which polymerizes in
presence of oxygen.
• Vulcanization of neoprene takes place in
presence of MgO.
• Properties:
Resistant to petroleum,
vegetable oils, light and heat.
• Uses:
Making pipes for transport of
gasoline.
Insulator cables.
Belts for power transmission.
Conveyor belts.