The document provides guidelines and an overview for a course on manufacturing and characterization of polymer matrix composites. It outlines expectations for assignments, class attendance, and tutorials. It also details the course modules which will cover fundamentals of polymers, chemical engineering principles for polymer processing, and polymer processing technologies. The modules will include topics like molecular characteristics, properties, rheology, heat transfer during processing, and specific processes like extrusion and injection molding. Students are provided a list of reference books and the document concludes with an example assignment calculation.

1. Manufacturing and
Characterization of Polymer
matrix composites
CH 62046
Prof. Swati Neogi
1
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2. Class Guideline
• Assignments and Class Test:
– Home assignments will be provided regularly to cover
all the topics discussed and is expected to be tried
home
– Assignments will be discussed in the class
– Folder containing assignments should be maintained
and should be brought in every class
– Assignments will be checked randomly on any day or
everyday
– Class test and surprise quiz will be taken time to time
2
*100% attendance is desirable. Proof is required for absence for any legitimate reasons

3. 3
Tutorials
1. Survey of manufacturing and testing equipment in the Composite Applications Laboratory (CAL)
a. Know the name and manufacturer of the equipment. Provide a schematic
b. Know the function and the type of product/test can be made with the equipment it makes
2. List at least 6 polymers from your everyday life and surroundings and explain
(a) Molecular structure, monomer used
(b) Applications
(c) Important property of the polymer which make them suitable for applications
1. Survey of raw materials available in the CAL
a. Know the name and manufacturer of the material.
b. Obtain the TDS. Explain and critically comment on the data on TDS about the usefulness of
the data provided in the TDS
c. Collect additional TDSs of resins and reinforcement from the website of different company and
critically comment on the property listed
2. Demo on manufacturing of composites using different fabrication technique
a. Make report
3. Demo on testing and characterization
a. Make report

4. Text Book
• No single text book will cover the entire subject. Take
class notes. Class notes are prepared based on
several books. Following is the list of books which can
be consulted for the course:
 Composites Manufacturing: Materials, Product, and Process
Engineering by Sanjay Mazumdar
 Fiber-reinforced Composites by P.K. Mallick
 Process Modeling in Composite Manufacturing by S. Advani
 Principles of Polymer Systems – Ferdinand Rodriguez
4
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5. Course Overview
Module 1: Fundamentals of Polymer (# of Lectures: 10-
12)
1.1: Introduction (2)
1.2Molecular characteristics-structure-processing-property
relationship (4)
1.3: Polymer properties (3)
1.5: Polymer additives (1)
5
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6. Course Overview
Module 2: Chemical Engineering Principles for Polymer
Processing (# of lectures: 14)
2.1: Introduction to polymer processing (1)
2.2: Polymer Rheology (3)
2.3: Mass and Momentum equations for isothermal polymer flow
analysis (5)
2.4: Heat transfer and viscous heat dissipation in polymer
processing (3)
2.5: Mass transfer, diffusivity and devolatilisation during polymer
processing (2)
6
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7. Course Overview
Module 3: Polymer Processing Technologies ( # of
Lectures: 18)
3.1: Extrusion (10)
3.2: Injection Molding(6)
3.3: Calendaring , Thermoforming, Others(2)
7
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8. Module 1: Course Outline
– Introduction of polymer (L2)
• Definition
• Advantages
• Classification of polymer
Thermoplastics:
Molecular characteristics-structure-property-processing Relationship(L3)
• Thermal Properties
– Melting point
– Glass transition
• Molecular
• Chemical composition
• MW/MWD
• Macroscopic
• Topology
• Orientation
• Phases
- Crystalline
- Amorphous
8
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9. Module 1: Course Outline
❑ Polymer properties (L4)
• Mechanical Properties
– Strength
– Modulus
– Elongation
– Toughness
– Impact
– Creep
– Permeability
9
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10. Module 1: Course Outline
• Chemical Properties
– Oxidation
– Thermal stability
– Degradability
– Chemical resistance
– Flammability/flame resistance
– UV resistance
• Melt properties
– Flow Characteristics
– Viscosity vs. Shear rate
– Shrinkage/cooling
– Polymer swelling/memory effect
❑ Polymer Additives (L0.5)
❑ Material selection and design guidelines (L0.5)
10
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11. Module 1: Fundamentals of Polymer
Section 1.1: Introduction
11
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12. Some Organic Basics
• Name following organic compounds and write down the
structure.
– CH4, C2H6,C2H2, C3H8, C2H4
• General name of following series of compounds
RCOOH, R-NH2, HO-R, HO-R-OH
write the product of following reaction:
RCOOH +RNH2 ---------
RCOOH +HOR --------------
RCOOH + HO-R-OH ---------
12
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13. Polymers
Processing with
additives
Finished Product
13
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14. Polymer, Resin, and Plastics
• A polymer is any substance made up of many of repeating units,
building blocks, called ‘mers’.
• When in form ready for further working, they are called ‘resins’.
• Polymers are seldom used in their neat form, most often
compounded with various additives. The resulting material is
usually referred to as a ‘plastic’.
• Frequently, polymers, resins, plastics are used interchangeably.
14
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15. 15

16. Basic Concept
16
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17. Basic Concept
• Polymer is large molecule having repeating unit
• Repeating structural units joined by covalent bonds
• Molecular weight can be up to 10000
• Monomers should have reactive functional group or double bond
• Basic linear chain is called backbones
• Molecular weight can be up to 10000
• Extensive formability and ductility
• Light weight, low cost
• Higher chemical reactivity
17
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18. Basic Concepts
• Compound of hydrogen and carbon, and/or O, N, F and
Si
• Low strength compared with metals; lower melting point
• Properties can be tailor made by choosing different
monomers, by blending different polymers.
18
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19. Forces In Polymer
• Primary force
– Covalent bonds within chain
• Secondary Force:
– Vander walls force between chains
– Hydrogen bonding
– Dipole-dipole interactions
• Chemical bonds between chains as in thermoset polymers
19
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20. Nomenclature
• Monomer - Molecule with minimum functionality of two
that reacts to form the structural units of the polymer
• Oligomer - Short chain synthesized from reaction of
several monomers (dimer, trimer, tetramer . . .)
• Polymer - Macromolecule generated through sequential
reaction of a small number of elementary units
• Repeating unit - Structure composed of the minimum
number of structural units necessary to generate the polymers.
• Degree of polymerization - number of repeating units
20
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21. COMMON MONOMERS AND POLYMERS
• Vinyl and Vinyledene monomer and their polymer
• Ester forming monomers and Polyester, Polycarbonate
• Amide forming monomers and Polyamide
21
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22. Common Vinyl and Vinyledene monomers
and Polymers
22
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23. Common Ester, Carbonate and Amide
Polymers
23
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24. Classification of Polymer
1. Based on their source
❑ Natural Polymers
• Rubber (latex), silk, jute
❑ Synthetic Polymers
- man-made polymers
- PET, PBT, Nylon
❑ Semi synthetic polymers
- Made by chemically treating natural polymers
- Vulcanized rubber, Rayon
24
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25. Classification of Polymer
2. Based on reaction Mechanism
❑Addition (Chain) Polymer
– Break a double bond
• PE,PP
❑Condensation (Step) Polymer
– Elimination of by product (except epoxies and polyurethanes)
• PET, PBT, Nylon
25
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26. Classification of Polymer
3. Based on molecular Structure
– Linear Chain
– Branched Chain
– Network or gel Polymer
26

27. Classification of Polymer
4. Based on Morphology
– Amorphous
– Crystalline/semicrystalline
5. Based on molecular composition
– Homopolymer
– Copolymer
• Alternate Copolymer: ABABAB
• Block Copolymer:AAAAAABBBBBBBAAAAAAABBBBB
– SBS (styrene-Butadiene-Styrene)
• Graft Copolymer: AAAAAAAAAAAAA
B
B
B
-High Impact Polystyrene, HIPS(Polystyrene with grafted polybutadiene)
27
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28. Classification of Polymer
6. Based on processing and response to temperature
– Thermoplastic: Melts/softens with temperature and can be
reprocessed
– Thermoset: Does not melt/soften with heat
28
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29. Module 1.2:Thermoplastic polymer
Section 1.2.1 Molecular characteristics-
structure-property-processing Relationship
29
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30. •Thermal
•Mechanical
•Rheological
•Chemical
•Other
•Chemistry
(mer
composition)
•Size
(molecular weight
distribution)
•Shape
•Topology
•Orientation
•Phases
Molecular
Characteristics
Structure
Properties Processes
Molecular characteristics-structure-property-processing Relationship
Intermolecular and Intramolecular forces
•Thermal
properties
•Rheology

31. Chemical Composition
• Chemical composition:
– Chemical nature of the monomers and the resulting nature of
backbones.
• Chemical Composition Determines
– Strength of the covalent bond.
– Intermolecular forces. Determines strengths .
• Dipole-dipole force as in PVC, Polyester.
• Hydrogen Bonding when polymer contains –OH and NH
groups.
– How closely they are packed. Determines morphology.
• Pendant groups such as Benzene ring, bulky side chains.
31
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32. Chemical Composition(contd.)
– How much flexibility
• Presence of non flexible groups in the backbone such as
amide, p-phenylene,sulfone, Carbonyl.
32
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33. Think!!!!!!
• How chemical composition will affect following
properties?
– Melting point?
– Crystallinity?
– Degradation/durability?
– Chemical resistance?
– Moisture absorption?
– Reactivity?
– Density?
33
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34. Molecular Weight and Distribution
Molecular weight:
– Polymer = (mer)n
– n is not a single number. It has a range. Theoretically, n can vary
from zero to Infinity
– Single polymer contains number of molecules with varying
weights.
– Usually the molecular weight of a polymer is characterized by
average molecular weight and a range of distribution
– The molecular weights of polymers are much larger than the
molecules usually encountered in organic chemistry
– Molecular weight and its distribution affects the properties
significantly
34
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35. Molecular Weight Distribution in Polymer
35
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36. Average Molecular Weights
• Different average values can be defined depending on
the statistical method that is applied. The weighted mean
can be taken with the weight fraction, the mole fraction
or the volume fraction:
– Weight average molar mass or Mw
– Number average molar mass or Mn
– Viscosity average molar mass or Mv
– Z average molar mass or Mz
36
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37. Average Molecular Weights
• Average Molecular weight based on Degree of
Polymerization(DP)
– DP is the number, n, of repeating units in the polymer chain.
– The molecular weight of a particular polymer molecule is a
product of the degree of polymerization and the molecular weight
of the repeating unit.
– DP based on average molecular weight
– DP based on number average molecular weight
37
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38. Number Average Molecular Weight
Number-Average Molecular
Weight
• The number average is the
simple arithmetic mean,
representing the total weight of
the molecules present divided
by the total number of
molecules.
• Ni: number of molecules with
mass Mi
• Pi: number average probablity
of Ni
38
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39. Weight Average Molecular Weight
• Weight-average emphasizes the mass of the molecules
so that the heavier molecules are more important.
• Pi : weight average probability of molecule Ni with mass
Mi
39
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40. Viscosity Average Molecular Weight
• One of the oldest methods of measuring the average
molecular weight of polymers is by solution viscosity.
The viscosity-average molecular weight lies somewhere
between the number average and the weight average
a is constant that depends on the polymer-solvent pair and on temperature
40
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41. Z Average Molecular Weight
41
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42. Comparison of Average Molecular Weights
Mn < Mv < Mw < Mz
42
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43. MWD: Polydispersity Index
• Molecular weight distribution also plays important role in
determining the properties along with the average
molecular weight.
• The weight-average molecular weight is larger than or
equal to the number-average molecular weight.
• The ratio of the weight-average and number-average
molecular weights, is a measure of the polydispersity of
a polymer mixture.
43
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44. MWD: Polydispersity Index
• Polydispersity Index indicates how widely distributed the
range of molecular weights are in the mixture.
• A ratio that is around 1.0 indicates that the range of
molecular weights in the mixture is narrow; a high ratio
indicates that the range is wide. With rare exceptions, all
synthetic polymers are polydisperse
44
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45. Polydispersity Index
Mi
Ni
45
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46. Molecular Weight and Properties
• MW ----> Viscosity ----> Processing hardness ---->Part
property
• Performance properties of finished product and
processing parameters affected by MW
• Tensile strength
• Impact strength
• Toughness
• Creep resistance
• Stress-crack resistance
• Elongation to break
• Reversible elasticity
• Melting temperature
• Melt viscosity
• Difficulty of processing
46
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47. Threshold and Working Molecular Weight
• Below a certain molecular weight, known as threshold
molecular weight, polymer does not exhibit its properties
for a particular application.
• Threshold MW depends on the Application.
– For adhesive, threshold MW is relatively low
– For high strength shaped plastic products, Threshold MW is
quite high
• With MW strength and other properties increases but
Viscosity increases due to chain entanglement.
• High viscosities create processing problems.
• Working Molecular Weight is defined as the MW
optimized for processing and properties.
47
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48. Molecular Weight and Properties
48
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49. Assignment:
6. Calculate number average molecular weight, weight average
molecular weight and polydispersity index from the following size
exclusion chromatography data.
Number of molecules Molecular weight
50 1000
45 2000
30 3000
40 5000
80 6000
25 7000
30 8000
20 9000
10 10000
49
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50. Assignment 3: Molecular characterization
and molecular weight
1. Why polymer characterization is so important for a
polymer engineer? List characterization parameters.
2. What is pendant group? Name and write the formula of
two polymers which has the pendant group identifying
pendant groups.
3. Write the formula for number average molecular weight,
weight average molecular weight and polydispersity
index.
50
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51. Calculate number average, weight average,
and polydispersity index
Number of Molecules Mass of each Molecule
1 800,000
3 750,000
5 700,000
8 650,000
10 600,000
13 550,000
20 500,000
13 450,000
10 400,000
8 350,000
5 300,000
3 250,000
1 200,000
51
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52. Number Average Molecular Weight
Number of Molecules, Ni Mass of Each Molecule, Mi Total Mass of Each Type of Molecule, NiMi
1 800,000 800,000
3 750,000 2,250,000
5 700,000 3,500,000
8 650,000 5,200,000
10 600,000 6,000,000
13 550,000 7,150,000
20 500,000 10,000,000
13 450,000 5,850,000
10 400,000 4,000,000
8 350,000 2,800,000
5 300,000 1,500,000
3 250,000 750,000
1 200,000 200,000
∑Ni = 100
∑NiMi = 50,000,000
Number average Molecular weight=5,00,000
52
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53. Weight Average MW & PDI
Number of Molecules
Mass of Each
Molecule
Total Mass of Each
Type of Molecule
Weight Fraction
Type of Molecule
(Ni) (Mi) (NiMi) (NiMi)/∑(NiMi) (WiMi)
1 800,000 800,000 0.016 12,800
3 750,000 2,250,000 0.045 33,750
5 700,000 3,500,000 0.070 49,000
8 650,000 5,200,000 0.104 67,600
10 600,000 6,000,000 0.120 72,000
13 550,000 7,150,000 0.143 78,650
20 500,000 10,000,000 0.200 100,000
13 450,000 5,850,000 0.117 52,650
10 400,000 4,000,000 0.080 32,000
8 350,000 2,800,000 0.056 19,600
5 300,000 1,500,000 0.030 9,000
3 250,000 750,000 0.015 3,750
1 200,000 200,000 0.004 800
∑WiMi = 531,600
PDI=531600/500000=1.063 53
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54. Topology
• Molecular topology is a description of molecules which
includes their stereo-chemical arrangement, branching,
formation of helices and network/looping/entanglement
characteristics.
• Physical properties of chain depends on interactions
between its chains.
• Interactions between chains depend on the shape of the
chain making up the backbone .
54
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55. Topology
55
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56. Topology
• Linear Polymers:
– Can form close packed structure
• Nonlinear (Branched) Polymers
– Some polymers, such as low density polyethylene
(LDPE), have branches of different sizes irregularly
spaced along the chain. Such polymers are said to be
nonlinear.
– Polymers with pendant groups, such as the methyl
group in polypropylene, are considered to be linear.
– The branches prevent the nonlinear molecules from
packing as closely as the linear, reducing their
density.
56
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57. Topology
• Cross linked and Network Polymers
– Some polymers have cross-links between polymer
chains creating three-dimensional networks.
– A high density of cross-linking restricts the motion of
the chains and leads to a rigid material.
• Different structure give rise to very different properties
• linear polyethylene has a melting point 20⁰C higher than
branched polyethylene. Unlike linear and branched
polymers, network polymers do not melt and will not
dissolve in solvents.
• The effect of structure on polymer properties is called the
“Structure-Property Relationship“.
57
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58. Isomerism
• Regularity of polymer chains decides the morphology.
• Highly irregular chains form amorphous polymer.
• Highly regular structure promotes crystalline growth.
• Some isomeric forms of polymer chains decrease the
regularity of chains reducing the probability of forming
crystalline structure.
58
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59. Isomerism
• Isomers are molecules
– with same molecular formula.
– Different arrangement of the atoms in space.
• Different arrangements which are simply due to the
molecule rotating as a whole, or rotating about particular
bonds is not considered as isomers.
59
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60. Isomerism
• Three forms of isomerism in polymers
– Monomer orientation
• Head-to-tail
• Head-to-head
– Geometric
• Cis isomerism
• trans isomerism
– Stereoisomerism or tacticity
• Isotactic
• Syndiotactic
• Atactic
60
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61. Monomer Orientation
• Monomers with pendant groups can attach in two ways.
– head-to-tail
– head-to-head
• The usual arrangement is head-to-tail with the pendant
groups on every other carbon atom in the chain.
Head to tail Head to head
61
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62. Geometric Isomerism
• Double bonds in the polymer chain can show cis- or trans-
isomerism. When a monomer with two conjugated double
bonds, such as isoprene, undergoes chain polymerization one
double bond can remain in the chain.
62
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63. Stereoisomerism
• Three different form
– Atactic (Random configuration)
– Isotactic (Same configuration)
– Syndiotactic (Alternating configuration)
63
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64. Stereoisomerism
64
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65. Stereoisomerism
• The physical properties of a polymer can have a strong
dependence on tacticity.
• Isotactic and Syndiotactic polypropylene have regular
structures, which allow favourable polymer-polymer
packing
• Atactic polyprop. has an irregular structure and poor
packing
• Isotactic and Syndiotactic forms have higher melting
temperatures (~165° and 130° C) and are poorly soluble
in many solvents.
• Atactic has lower melting temp (< 0° C), is soft, rubbery,
and can be moulded. It is also more soluble in most
solvents.
65
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66. Morphology
• Polymer morphology is the overall description of polymer
structure including phases
• Morphology is determined by
– Topology
o linear, branched, cross-linked
– Molecular Weight
• Phases of polymer
– Crystalline phase
– Amorphous phase
66
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67. Amorphous Phase
• Polymer chains with branches or irregular pendant
groups cannot pack together regularly enough to form
crystals. These polymers are said to be amorphous.
• Amorphous polymers are
– softer
– have lower melting points
– penetrated more by solvents
67
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68. Crystalline Phase
• Polymer chains without branches or bulkier pendant groups can
pack together regularly enough to form crystals. These polymers are
called crystalline polymers
• Polymers are semi crystalline
• Highly crystalline polymers
– rigid
– high melting,
– less affected by solvent penetration
– strong but with low impact resistance
• Polymer Molecules form lamella
68
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69. Spherulites
✔ When a molten crystallizable
polymer cools, the crystals
grow from individual nuclei and
radiate out like the spokes of a
bicycle wheel
✔ The crystalline portions
actually radiate out in in three
dimensions, forming spheres
that are called spherulites
✔ In a sample of a crystalline
polymer there are billions of
spherulites
69
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70. Spherulite
70
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71. 71
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72. Factors Affecting Crystallinity
⮚ Structural Regularity
⮚ Degree of Polymerization
⮚ Intermolecular Forces
⮚ Pendant Groups
⮚ Processing
▪ Rate of Cooling
▪ Orientation
72
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73. Structural Regularity
• Structural regularity promotes crystallization
• Crystallization is favoured by
– Linear structure
– High degree of symmetry
o Syndiotactic and or isotactic isomers
• Limited crystallization can take place if a small number of
branches are present.
73
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74. Degree of Polymerization
⮚ Relatively short polymer chains form crystals more
readily than long chains, because the long chains tend
to be more tangled.
⮚ High crystallinity generally means a stronger material,
but low molecular weight polymers usually are weaker
in strength even if they are highly crystalline
⮚ Low molecular weight polymers have a low degree of
chain entanglement, so the polymer chains can slide by
each other and cause a break in the material.
74
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75. Intermolecular Forces
⮚ Crystallinity is favoured by strong inter backbone forces
⮚ The presence of polar and hydrogen bonding groups
favours crystallinity because they make possible dipole-
dipole and hydrogen bonding intermolecular forces
⮚ Polyethylene Terephthalate, contains polar ester
groups. Dipole-dipole forces between the polar groups
hold the PET molecules in strong crystals.
75
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76. Pendant Groups
⮚ Regular polymers with small pendant groups crystallize
more readily than do polymers with large, bulky pendant
groups
⮚ Poly vinyl alcohol (PVA) is made by the hydrolysis of
poly vinyl acetate ) (PVAc). PVA crystallizes more readily
than PVAc because of the bulky acetate groups in PVAc.
The -OH groups in PVA also form strong hydrogen
bonds.
PVAc PVA 76
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77. Processing : Cooling Rate
✔ Major difference between small molecules and polymers is that the
morphology of a polymer is dependent on its thermal history
✔ The crystallinity of a polymer can be changed by cooling the polymer
melt slowly or quickly, and by "pulling" the bulk material either during
its synthesis or during its processing
✔ When they are processed industrially, polymers often are cooled
rapidly from the melt. In this situation, crystallization is controlled by
kinetics rather than thermodynamics
✔ There may not be time for the chains, which are entangled in the
melt, to separate enough to form crystals, so the amorphous nature
of the melt is "frozen into" the solid
✔ A polymer is more likely to have a higher percent crystallinity if it is
cooled slowly from the melt.
77
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78. Processing: Orientation
✔ Crystallinity can be enhanced by stretching the bulk material either
when it is synthesized or during its processing
✔ Induced crystallization due to orientation is common for both films
and fibres
✔ When a film is formed the small crystallites tend to be randomly
oriented relative to each other. Drawing (stretching) the film pulls
the individual chains into a roughly parallel organization
✔ Films can either be uniaxially oriented (oriented in only one
direction) or biaxially oriented (oriented in two directions).
✔ Fibers normally are drawn so that they are oriented in one direction.
Unstretched nylon fibers are brittle, for example.. When the fibers
are stretched the oriented fibers are strong and tough.
78
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79. Polymer Properties
• Thermal Properties
– Melting point
– Glass transition
– Thermal stability
• Mechanical Properties
– Strength
– Modulus
– Elongation
– Toughness
– Impact
– Creep
– Stress Relaxation
79
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80. Polymer Properties
• Chemical Properties
– Oxidation
– Thermooxidative stability
– Degradability
– Chemical resistance
– Flammability/flame resistance
– UV resistance
• Melt properties
– Polymer Rheology
o Flow Characteristics
o Viscosity vs. Shear rate
– Shrinkage/cooling
– Polymer swelling/memory effect
• Other
– Electrical properties
80
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81. Thermal Properties
Semicrystalline
polymer
Heat, Tm
Molten
polymer
Heat, Tg
Glassy
State
81
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82. Glass Transition Temperature
• Above Tg polymers are rubbery whereas below Tg,
polymers are glassy
• Rubbery behavior due to polymers ability to change its
conformation at high temperature
• Glassy behaviour due to lack of ability to change
conformation at low temperature
82
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83. Change in modulus with Tg
83
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84. Factors Affecting Tg
•Backbone-Polar groups increases Tg
•Molecular Weight
•Pendant Group
•Cross linking
–-Tg in creases with cross link density
•Plasticizer
-Plasticizer decreases Tg
84
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85. Factors Affecting Melting point
⮚ Melting temperature depends on % Crystallinity
⮚ Chemical composition
⮚ Chain entanglement
85
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86. 86
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87. 87
crystallization
DSC curve of a polymer

88. 88
First heating
cycle
Cooling cycle
Cycle 1
Cycle 2
Cycle 3
crystallization
DSC curve of a thermoplastic polymer (HDPE)

89. Effect of Crystallinity on Properties
89
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90. Mechanical Properties
⮚ Tensile strength: Resistance to stretching
⮚ Compressive strength: Resistance to compression
⮚ Flexural strength: Resistance to bending (flexing)
⮚ Impact strength: Resistance to sudden stress, like a hammer blow
⮚ Fatigue: Resistance to repeated applications of tensile, flexural, or
compressive stress
⮚ Creep: Increase in strain when a polymer sample is subjected to a
constant stress (typical Viscoelastic Properties): time dependent
⮚ Stress relaxation: Decrease in stress when a sample is elongated
rapidly to constant strain (typical Viscoelastic Properties): time
dependent
90
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