1. University of Engineering and Technology, Peshawar
Materials Engineering Department
Presented BY:
Mohsin Ali Marwat
&
Adil Jan
Presented To:
Dr. Afzal Khan

2. Contents
 Introduction
 Types of Polymers
 Fabrication Techniques
 Mechanical Behavior
 Characterization Techniques
 Applications
 Latest Research
Polymer
Materials

3. Monomer:
It is the smaller molecule(s) that are used to prepare a
polymer
Oligomer:
 A molecule having a reaction of several repeating units.
 Not large enough to be consider a polymer
 (dimer , trimer, tetramer)
Polymer:
 A large molecule consisting of a number of
repeating units
 Its molecular weight is typically several
thousand or higher
Definitions
Introduction

4.  Low Density
 Good corrosion resistance
 Good moldability
 Excellent surface finish can be obtained
 Economical
 Low coefficient of friction
 Lower to higher mechanical properties
 Chain Length
 Branching
 Side groups
 Crosslinking)
 Can be produced transparent or in different colours
 Poor tensile strength and temperature resistance
Characteristics
Introduction CHARACTERISTICS OF POLYMERS

5. Classification on the basis of Origin
 Natural/Bio polymers
 Proteins
 Polypeptides
 Polynucleotide
 Polysaccharides
 Natural rubber
 Synthetic organic polymers
 Semi-synthetic polymers
 Inorganic polymers
 Siloxanes
 Silanes
 phosphazenes)
Classification
Classification
of Polymers

6. Classification by Monomer Composition
Homo-polymer Copolymer
Block Graft Alternating Statistical
Homo-polymer
Consist of only one type of constitutional repeating unit (A)
e.g. A-A-A-A-A-A-A-A-A
Copolymer
Consists of two or more constitutional repeating units (A.B )
Classification
Classification
of Polymers

7. Random copolymer
two or more different repeating unit
are distributed randomly e.g.
Alternating copolymer
They are made of alternating sequences
of the different monomers e.g.
Block copolymer
Long sequences of a monomer are
followed by long sequences of another
monomer e.g.
Graft copolymer
One type of monomers with branches of
another type
Classification on the basis of Chain Structure
Classification
Classification
of Polymers

8. Classification by polymerization
Classification
Condensation Polymerization:
A type of polymerization in which monomers combine together
in such a way that they eliminate small molecules like H2O.
Addition Polymerization:
A type of polymerization that involves the rearrangement of
bonds within the monomer in such a way that the monomers
link up directly with each other.
Classification
of Polymers

9. Classification on the basis recyclability/temperature
Response
Classification
Classification
of Polymers

10. Elastomers:
Materials with very low modulus of elasticity and high
extensibility
Plastics:
Polymers in which, when a sufficiently intense force is
applied, they irreversibly deform
Fibers:
Present a high modulus of elasticity and low extensibility
Coatings:
Polymers that are used to modify the surface of a material
Adhesives:
Polymers that are used to adhere/join other materials
Types on the basis of Applications
Classification
Classification
of Polymers

11. Fabrication Methods
 Compression Molding
Methods
Fabrication
 Injection Molding

12.  Blow Molding
Methods
Fabrication
 Extrusion

13. Mechanical Behavior of Polymers
Figure: The effect of temperature on
the stress-rupture behavior of high-
density polyethylene.

14. Techniques
Characterization
Characterization Techniques
Morphology Testing:
 SEM
 TEM
 AFM
Thermal Analysis:
 DSC
 TGA
Molecular Structure
Testing:
 Infrared spectroscopy
 Raman spectroscopy
 NMR spectroscopy
Mechanical Analysis:
 Tensile Testing
 Dynamic mechanical
analysis
 Shore Hardness

15. Applications

16. 1. The Self-Healing Polymers
2. High melting temperature Polymers
3. Electrical conductive polymers
Research
Latest Research:

17. Adil Jan

18. Introduction
Viscoelasticity:
 the property of materials that exhibit both
viscous and elastic characteristics when
undergoing deformation.
 It was examined in the late twentieth
century.
Introduction

19. Properties of viscoelastics
 Hysteresis is seen in the stress–strain
curve.
 Stress relaxation occurs:
 step constant strain causes decreasing
stress
 Creep occurs:
 step constant stress causes increasing
strain
Properties

20. Types of viscoelasticity
• Linear viscoelasticity
• Non-linear viscoelasticity
Types

21. Models of viscoelasticity
• Maxwell model
• Kelvin-Voigt model
• Standard linear solid model
Models

22. Viscoelasticity in terms of Polymers
• At low temperature, it is elastic
• At high temperature, it is liquid or
viscous.
• Combined mechanical characteristics
are termed as viscoelasticity.
In terms of
Polymers

23. VISCOELASTIC RELAXATION MODULUS
• Viscoelastic behavior depends upon
– Time
– TemperatureRelaxation
Modulus

24. • Relaxation modulus as a function
of time
Er (t) = σ(t)/ϵ0Relaxation
Models
Contd..

25. • Isothermal stress relaxation
Relaxation
Models
Contd..

26. Viscoelastic Creep
• Polymeric materials are susceptible
to time dependent deformation
when the stress level is maintained
constant; such deformation is
termed viscoelastic creep.
Ec (t) = σ0 / ϵ(t)
Creep

27. Measuring viscoelasticity
• Resonant Ultrasound
Spectroscopy (RUS)
• Broadband Viscoelastic
Spectroscopy (BVS)
Characterization