MATERIALS and their USES
- general index AND a comparison survey - examples of uses of materials, relating their properties to
a particular application
Doc
Brown's Chemistry GCSE/IGCSE/O level Revision Notes
Materials science is the
study of the properties of solid
materials and how those properties are determined by a
material’s composition and structure and how we use these materials in various
applications from building constriction, and engineering to a huge variety of
objects in the home.
This page
surveys how we use different materials, their properties and how to choose a material for a particular use
or application.
All my
GCSE Chemistry Revision
notes
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Sub-index for this page
1.
Examples of how we use materials - the end products of
materials science!
2.
Natural and
synthetic materials
3.
Typical important physical properties of
materials
4.
A
summary of four widely used types of materials, their properties and uses
5.
Case study 1. Properties
- choosing materials for car construction
6a.
Case study 2. Properties
-
choosing materials for particular 'domestic' uses
6b.
Case study 3. Choosing a material for particular engineering
applications
7.
Useful extra reading
links on materials, their properties and uses
8.
Nanochemistry and smart materials index links
9.
A comparison of the
structure and bonding of different substances - with reference to their use as
solid structural materials
Doc Brown's
chemistry revision notes: basic school chemistry science GCSE chemistry, IGCSE chemistry, O level
& ~US grades 8, 9 and 10 school science courses or equivalent for ~14-16 year old
science students for national examinations in chemistry
1. Examples of how we use materials - the end products of
materials science!
CERAMICS
Ceramics are
usually:
(i) poor conductors of heat and
electricity, hence used thermal and electrical insulators,
(ii) strong and hard wearing, but
brittle,
(iii) high melting points - so
thermally very stable,
(iv) they don't corrode or degrade
when exposed to the weather like metals do.
Most of the glass we use is relatively cheap
soda-lime glass, made by heating a mixture of sand, sodium carbonate and
limestone
Many ceramic materials are
made from clay, a softish material dug out of the ground.
Clay,
composed of fine particles of weathered rock, is quite soft with a
little moisture and easily moulded into any shape. When heated to a high
temperature in an oven it is transformed into a hard, if brittle,
material. It is thermally stable and insulating. Its an ideal material
for making pottery and bricks - the latter is very strong in
compression, so can be used in load bearing walls in the building
industry.
Glass is also classed as a
ceramic. It can be moulded when hot and is usually transparent.
Soda-lime glass is made by
heating limestone (mainly calcium carbonate, CaCO3), sand
(mainly silica, SiO2) and sodium carbonate. When the
molten mixture is cooled, glass is formed. It is brittle and
relatively low melting.
Borosilicate glass is made
in a similar same way, by melting together mainly silica (silicon
dioxide, SiO2) with a smaller amount of boron oxide (B2O3). It has a higher melting point than soda-lime glass and is
better at withstanding sudden changes in temperature. Borosilicate
glass has many uses e.g. laboratory glassware (Pyrex is a trademark
name), scientific lenses and hot mirrors, bakeware and cookware,
thermal insulation, high-intensity lighting products and aquarium
heaters.
The biggest uses of glass are
windows and apparatus in laboratories or chemical plants.
Glass is very hard wearing,
doesn't corrode, although brittle, it lasts longer than plastic.
(see
also limestone chemistry,
glass and ceramics).
POLYMERS - many types with varied properties
The properties of
polymers depend on what
monomers they are made from and the conditions under which they are made.
Most polymers are:
(i) poor conductors of heat and
electricity - so used as thermal or electrical insulators.
(ii) thermosoftening polymers are readily moulded into any shape,
(iii) often cheaper for mass
production than most other
materials,
(iv) less dense than most other
materials, more 'lightweight' materials than metals or ceramics,
(v) they can degrade over many years,
particularly if exposed to sunlight.
(i) Thermosoftening polymers consisting of individual, tangled polymer chains and
melt relatively easily when they are heated.
For
example, low density (LD) and high density (HD) poly(ethene) are produced from
ethene using different catalysts and reaction conditions (see
thermosoftening addition polymer notes).
Strong rigid high density
poly(ethene) is used for water pipes. Poly(propene) and PVC are also
strong and also used for piping and guttering and PVC used for
weatherproof window frames.
Lighter and more flexible low
density poly(ethene) is use for plastic bags and 'squeezy' wash
bottles in the laboratory.
Polystyrene foam is used in
packaging and thermal insulation, light but flammable and not easy
to recycle!
Some thermosoftening polymers, like
nylon, can also be drawn out into strong fibres.
These thermosoftening polymers contrast with
(ii) thermosetting polymers
which consist of polymer chains with cross-links between them
and so they do not melt when they are heated (see
thermosetting polymer notes).
Polymers like melamine are much
stronger and heat resistant and can be used as worktops or appliance
casings.
COMPOSITES - varied compositions
Most
composites are made of two materials,
(i) a matrix or binder surrounding and binding together (ii) fibres or fragments
of the other material, which is called the reinforcement. Examples of composites
include
Wood is a natural composite of cellulose
fibres strongly held together by a polymer matrix chemically derived from
cross-linked cellulose molecules (similar in this respect to man-made
thermosetting resin).
See also
natural polymers, structure, function and
uses
Concrete is a mixture (aggregate of sand,
gravel and cement) - the sand and gravel act as reinforcement, used for
basement flooring and road surfaces, but the concrete can also be set with
reinforced with steel rods embedded in it, widely used as a building construction
material. Concrete is very strong in compression.
Resin-fibreglass - the polymer monomer
mixture polymerises via a catalyst and sets hard to form a hard strongly
bonded material (thermosetting polymer) and the set resin reinforced by the
glass fibres embedded in it, this is a very strong, but low density
composite material, used for car body work, boat hulls, sports equipment e.g.
surfboards, skis,
Some more technologically
advanced composites are made from carbon fibres or carbon nanotubes instead of
glass fibres.
Carbon fibre composites are based on a polymer matrix which are
reinforced by very strong carbon fibres or carbon nanotubes.
These composites are very
strong and of low density ('light'), they are quite costly to produce but
are widely used in the aerospace industry, sports car bodies.
Composites based on the very strong polymer
Kevlar ®, a
reinforcing material embedded in another material. Kevlar adds strength
with little extra weight. Kevlar has a high tensile strength, tough and
hard wearing and good thermal stability.
Kevlar was developed for demanding industrial and
advanced-technology applications. Kevlar is as strong as the best carbon
fibre and stronger than steel wire for the same thickness!!!
Kevlar has many applications, including bicycle tyres and racing yacht
sails and body armour e.g. bulletproof vests - all physically demanding
situations that benefit from the high tensile strength-to-weight ratio
of Kevlar composites.
All sorts of composites are being
designed all the time, many replacing metals.
METALS - usually alloys
Metals have a wide range of uses e.g. in
the car industry, building industry, household appliances, electrical
circuits.
Metals are usually:
(i) quite or very dense,
(ii) have high melting points -
most thermally quite stable for most uses,
(iii) malleable - easily moulded
into shape, less brittle than composites, can deform under stress
without breaking,
(iv) ductile - can be drawn out
into wire - including twisting strands of steel together to form
strong cables,
(v) varying strength and
hardness, particularly when alloyed (mixed) with other elements,
(vi) good conductors of heat and
electricity - many applications as thermal or electrical conductors,
(vii)
For lots of other details see
Transition and other metals,
including alloys
It is
important to be able to compare the physical properties of glass and clay
ceramics, polymers, composites and metals and explain how the properties of materials are related to their uses and select
an appropriate material for a particular use.
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2.
Natural and synthetic materials
Reminders: All materials are
atoms of various elements and they may be pure elements, pure compounds or
mixtures of elements and compounds.
For definitions and explanations
with examples see
Some important
ideas and definitions in Chemistry.
This section is more about ideas and decision making
than learning lots of facts.
Be able to explain why a material is best suited for
a particular purpose based on its characteristic properties.
Naturally occurring materials which have proved
useful
Materials from plants e.g.
The timber from trees is used as a
construction material and pulped to make paper.
The cotton to make clothing fabrics
is grown in fields of the cotton plant.
Latex rubber is collected as a sticky
fluid from rubber trees
Materials from
animals e.g
Wool for clothing comes from shearing
sheep.
Leather goods are made from the skin
of cows.
Silk, a fine weaving material is
obtained from silkworm larva.
To compliment, and in many cases supersede these
naturally occurring materials, we humans have developed an enormous range of ...
Synthetic materials
e.g.
The main advantage of man-made synthetic
materials compared to natural materials is that you can design their
properties to suit a particular use and develop a better product by
chemically changing the structure of the material and how it is processed.
The extraction of metals from raw
materials from the Earth's crust - ores are mined and processed to produce iron, copper, titanium,
aluminium, which are converted into lots of different things and variety of
properties enhanced by making alloys to suit specific technical
needs.
Plastics - polymers with a huge range of
properties and uses have been developed from the products of crude oil in
the petrochemical industry e.g.
Synthetic fibres like nylon and polyester
can replace silk, cotton, wool and they can be made strong but
flexible/stretchy, waterproof ...
plastics don't rot like wood so can replace wooden
window frames, they don't corrode like metals to can replace iron/lead
piping and guttering,
synthetic rubber polymers replaces natural rubber
from the sap of the rubber tree - though car tyres are still made of natural rubber and other materials,
polymers have now been developed that can replace rubber - another
organic molecule product from oil,
insulating thinsulate can replace natural wool and
cotton for protective clothing,
synthetic pigments mixed with solvents and
binding agents make hard wearing long lasting coatings, and have mainly replaced traditional paints made from mineral
powders + egg yoke + linseed oil.
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3. Typical important physical properties of
materials
Mainly physical characteristics
here, but chemical character is very important too and it is the properties of a
material that decide what it can be used for. So, knowledge of the properties of
materials helps you to decide on the suitability of a material for a particular
purpose i.e. what is best for the job! The effectiveness of a material is
how good it is for the function its supposed comply with.
For properties like strength,
stiffness and hardness, you would need to do a 'fair test' of pieces of
the same size material to get an accurate comparison e.g. a similar rectangular
block.
Strength of a solid
The strength of a material is
measure of how much it can resist a force applied to it.
You might measure the force to
break a bar of the material, or what force is needed to permanently deform
it, that is changing its shape without snapping it.
There are two types of strength
values of importance, depending on how you apply the force to a material.
Tensile strength
This is how much a material
can resist being pulled (stretched) in tension until it breaks or
deforms.
This depends on how strong the
particles are held together in the solid's bond network.
Pure metals are weak because layers
of atoms can side over each other, stretching and bending the metal, but
alloying the metal with other elements can inhibit this.
See
Metal alloys -
improved design and strength
Ropes or chains on pulley
systems for lifting objects or steel cables supporting the road of a
suspension bridge, all need to have a high tensile strength or they
would snap under the weight of the load!
Ionic compounds are strong in tensile
and compressive strength because the ions are strongly held in the giant
ionic lattice, but they are usually brittle and of new use for making
useful objects.
Compressive strength
This is how much a material
can be compressed ('pushed' or 'squashed') before it gives way or
permanently deformed.
Building construction
materials like stone, bricks or concrete all have a high 'compression'
strength which is needed to support the weight of the rest of the
building they support.
Combination of tensile plus
compression strength
Sometimes materials must be strong in
both tension and compression e.g. concrete is strong in compression but
weak in tension. For these reason its tensile strength is increases by
adding steel rods to reinforce the concrete.
Stiffness of a solid
The stiffness of a material is a
measure of how easily it bends when a force is applied to it, but without
permanently deforming it i.e. the material springs back to its original
shape. A very stiff material hardly bends when a force is supplied.
Materials like stone, brick
and concrete are very inflexible - fortunately!, but blocks of most plastics and wood
are flexible and will all bend to some extent without breaking. Rubber
is one of the most flexible of materials and can be bent and stretched
by quite some margin and still spring back to its original shape. Often,
flexibility is desirable in a plastic or rubber object e.g. insulated
cable of electrical appliances or blowing up a balloon.
Note that the thickness of
the material is important when considering 'stiffness'. Thin sheets of
almost any solid can be bent so far without breaking e.g. strands of
glass fibre, steel spring.
Hardness of a solid
The hardness of a material is a
measure of difficult it is to cut into, so materials like diamond and
granite are very hard and butter and sodium metals are soft materials and
easily cut into.
Diamond is one of the
hardest substance is know and is used to put a strong cutting edge on
cutting tools and some industrial drills have diamond tipped tips.
Diamonds are so hard that they can only be cut by other diamonds!
Brittleness of a solid
Brittle materials break and shatter quite
easily if hit by a rapidly applied force.
The particles in brittle solids are held
together very strongly and cannot move without permanently breaking bonds.
Most ceramic materials like glass or
pottery easily shatter when struck hard with another hard solid object.
Even diamond can be cut by a skilled
cutter by breaking down a line of apparently strong C-C covalent bonds!
Similarly, planes of ions, held by strong
electrostatic bonds, can be cleaved apart or slid over each other, making
most ionic compounds brittle when struck with a hard object - or stressed in
a salt cellar where steel metal blades are rotated to cut up large salt
crystals into smaller crystals for sprinkling on food.
Most metals (pure or alloyed) are not
brittle because the layers of atoms can slide over each other without
permanently breaking the bonds between the metal ions in the giant lattice
and the delocalised electrons.
How easily can the solid material be
reshaped (deformed)
Materials that can be deformed without
breaking are useful for shaping particular object.
The particles in such materials, can move
without the bonds being permanently broken.
Metals, particularly if pure, are quite
malleable and easily bent-moulded into a specific shape because the layers
of atoms can slide over each other without permanently breaking the bonds.
Thermosoftening polymers, without
cross-link bonds, are quite easily shaped, usually after heating
sufficiently to soften or even melt the plastic prior to moulding.
Note that you can't warm and reshape
thermoset polymers, the extra cross linking bonds won't allow this - not
surprisingly, they are harder and more brittle than thermosoftening
polymers..
Electrical and thermal conductivity of a
solid
These two properties often go together
e.g.
Metals are good conductors of heat and
electricity because the thermal kinetic energy and electrical energy is
transferred by the delocalised electrons moving through the giant metal
lattice.
Non-metallic structures like carbon in
the forms of graphite, graphene and some nanotubes, are also moderate or
very good conductors of heat and electricity because electrons can move
through the structure.
Most non-metallic solid materials without
free particles that can carry either electrical energy or thermal kinetic
energy, tend to heat or electrical insulators - which makes them equally
useful materials.
Ceramic materials are used as electrical
insulators where high voltages are involved e.g. look up at pylons and local
cable poles of the National Grid electricity supply - you can see the
insulating ceramic rings on the cables.
Density of a solid
The density of an object is a
measure of the mass of an object in a particular volume.
Density = mass / volume and is
usually measured in g/cm3 or
x this by 1000 = kg / m3
The density of water is 1.00
g/cm3, the plastics poly(ethene) and poly(propene) are 0.92
to 0.98 g/cm3 (hence they float on water polluting the
surfaces of rivers, lakes and seas), nylon is 1.11 to 1.18 g/cm3.
Metals
have a wide range of density e.g. sodium floats on water, but most
metals sink in water (unless you shape them like a boat!).
For many contexts of
construction like aircraft wings and fuselage you would like a like a
low density ('lightweight') material hence the use of aluminium and
titanium alloys rather than steel.
Densities of some metals
in g/cm3: sodium 0.97, aluminium 2.70, titanium 4.54,
iron (~steel) 7.87, gold 19.30
States of matter density: solid
> liquid >>> gas.
Solids and liquids have the highest densities because the
particles are close together - more mass per unit volume.
Gases have very low densities because the
molecules are so far apart as they fly around through mainly empty space!
Durability of a solid material
Durability isn't something that
is easily quantified, but you should expect any product to have a reasonable
'working life'. Phrases like 'hard wearing', 'weather resistant' are a bit
vague, but they mean a lot to the consumer!
So, how long will the
material of a product last? or should last?
You don't want clothing
fabrics wearing away after a few months of wear, you expect the soles of
you shoes to last a reasonable length of time.
You don't want a carrier bag
to fall apart before your reach the car after leaving the supermarket!
You don't want the car tyres
wearing away after just a few thousand miles!
Melting point of a solid
Very pure materials have quite
sharp melting points where the solid becomes a liquid e.g. water 0oC,
sodium chloride 801oC.
However, many materials are a mixture of
different materials e.g. metal alloys or a range of different sized
molecules e.g. thermoplastics like poly(ethene), and in these cases the
material tends to melt over a wider temperature range.
In the case of
polymers, they have a softening point and very gradually become a liquid
over the next few tens of degrees rise in temperature.
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4. A summary of
four widely used types of materials, their properties and uses
Which you should be able to relate to their
uses, and of course, where they are not used!
What a material can be used for is very
dependant on its properties, though cost can be a significant factor too.
A comparison
of four groups of materials |
Property/material |
1. metals -
many similar properties, but alloys have very
variable strength and melting point |
2. polymers - plastics
- properties very dependent on whether thermosoftening or thermosetting |
3. glass, bricks and other ceramics |
4. composites
- properties very dependent on the particular reinforcement embedded in
the matrix-binder |
Hardness - strength - rigidity -
brittleness |
usually strong and fairly
rigid, but may need alloying with other metals to make them stronger,
not brittle |
relatively soft and flexible
without breaking, though thermosetting polymers (thermosets) or rigid
PVC can be quite hard and brittle, |
very hard and rigid, not
flexible, but brittle and easily shatter when struck |
They can be very tough
and durable |
Examples of
relative tensile strength |
mild steel 250, high
tensile steel 340, pure aluminium 60-120, strong aluminium alloy 240-400 |
Perspex 55-70, PVC
20-60, low density poly(ethene) 15, high density poly(ethene) 29, nylons
45-90 |
brittle! |
natural wood 11-25,
fibreglass reinforced polyester 70-500, rigid polyester 40-60, epoxide
resin 30-80 |
Examples of
density (kg/m3)
÷ 1000 = g/cm3 |
moderate to high: steels
~7700, pure aluminium 2700, alloyed aluminium 2800, titanium alloys
~4500 |
low: low density
poly(ethene) 920, high density poly(ethene) 960, nylons 1100-1140 |
moderate: bricks
1300-2000, glass typically 2180-2530, earthenware and china 2500-2800 |
low-moderate: low if
based on carbon chains, oak wood 720, balsa wood 200, concrete
2200-2400, glass-fibre reinforced polyester 1500-2000, |
Heat related properties |
usually high melting point |
relative low softening -
melting points, thermosets may not melt but degrade at higher
temperatures |
high melting point |
concrete has good thermal
stability |
Thermal (heat conductivity) |
very good thermal
conductors |
usually good thermal
insulators |
good thermal insulator |
concrete is an insulator |
Electrical conductivity |
very good thermal
conductors |
usually good electrical
insulators |
good electrical insulator |
- |
Malleability, ductility, can it be
moulded |
malleable (easily pressed or
beaten into shape), ductile (easily drawn out into wire) |
some polymers can be drawn
out to form quite strong fibres, thermosoftening plastics are easily
moulded when warmed |
wet clay can be moulded
before firing in a furnace, but not afterwards! |
composites are malleable or
ductile, can't be moulded, but resins can be cast in moulds |
Durability to the environment
(e.g. water, atmosphere) |
may need protection from
corrosion which is relatively cheap low carbon steel, aluminium has
natural protective oxide layer, non-porous, |
water repellent surface,
don't corrode like metals |
bricks are porous to water,
but glass is not porous and water-proof |
- |
Miscellaneous properties |
attractive shiny surface,
|
Can be dyed any colour
you want. |
Glass objects e.g.
windows, are usually transparent. |
properties depend on the
composition e.g. matrix, binder or reinforcement |
Uses
See also opening paragraphs of this section |
electrical wiring, cutlery,
strong sheeting e.g. aircraft, ships, car bodies |
clothing, insulators in
electrical appliances, |
See borosilicate glass
above. |
Boat hulls, sports
equipment like tennis rackets, car bodies |
Unsuitable uses! |
no good for
electrical or heat insulation, anything that might corrode which could
be replaced e.g. with non-corroding plastic. |
- |
Any situation involving
mechanical vibration - ceramics are brittle. |
- |
Property/material |
1. metals - alloys |
2. polymers - plastics |
3. glass, bricks and other ceramics |
4. composites |
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5. Case study 1.
Properties and
choosing materials for car construction
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6a. Case study 2. Properties and
choosing a material for particular 'domestic' uses
Actually, lots on 'mini-cases' of
'suitability' to get you thinking as broadly as possible!
-
Electrical wiring - most circuits
in the mains supply or in appliances are made of copper - quite strong but
flexible, ductile (can be drawn out into a wires) and an excellent
electrical conductor. The pins on plugs are usually made of brass alloy (Cu
+ Zn).
-
BUT, all wiring needs insulating, so the
copper wire is sheathed in tough, but flexible polymers like PVC, which are
a good electrical insulator. Plugs and sockets are made of tough hard
plastic which can be also PVC or poly(propene),
-
Cooking utensils for the
kitchen need to be made of a strong, high melting, good heat conducting, not
toxic (aluminum is not used now!) material like stainless steel or iron.
-
Children's toys must be
made of a tough durable material (stiff & strong), that is non-toxic,
hard-wearing (''play resistant'!) and of low density.
-
Not surprisingly,
thermosoftening plastics like poly(ethene) and poly(propene) are mass
produced to fulfil our children's needs, and such plastics are easily
moulded into an infinitely range of objects, which are readily brightly
coloured with an array of pigments!
-
Clothing fabric needs to
be made of hard wearing fibres like Nylon or Terylene with a high tensile
strength, but it mustn't be stiff (must be very flexible) and in the case of
children's clothing or nightwear it must be fire resistant - so the material
must incorporate a flame retardant substance.
-
Many 'older' materials have
been replaced by more 'modern' synthetic materials e.g.
-
Strong plastics like
poly(propene) have replaced iron for drain-pipes and guttering. The
plastic doesn't break easily like brittle iron AND they don't rust and
corrode away in bad weather!
-
Some compact discs (CDs)
were originally made using a layer of aluminium to digitally record the
sound, but this was prone to slow corrosion, so after some time the
sound quality of reproduction deteriorated. CDs are now made from a very
tough, hard wearing and slightly flexible polycarbonate plastic that
will NOT corrode! (being plastic!) ...
-
... and while we are in the
music business, very old records were made of a very brittle material
that easily shattered and so few have survived, but modern 'vinyl
records' are made from strong and slightly flexible PVC plastic
[poly(chloroethene), old name polyvinyl chloride] which is far
less likely to break, even if dropped!
-
Plastics - polymers have
a wide variety of physical characteristics, they can be hard, strong, stiff
(rigid), flexible, low or high density, soften easily on heating or quite
heat resistant.
-
Some are easily moulded when softened on heating
(thermosoftening used to make cheap toys).
-
Others set really
hard and are strong and don't melt (thermosets used for kitchen worktops and
plastic kettles),
-
Strong fibres
like nylon are used for outdoor clothing and ropes.
-
Tough wearing and rigid PVC or
poly(propene) are used for piping, guttering and window frames - they do not
corrode like metal and don't require painting - you can dye the plastic
whatever colour you like when fabricating the final product.
-
I've described lots of
examples on other pages ....
-
Polymerisation, plastics,
poly(ethene), poly(propene), uses, problems, recycling
-
Condensation polymers, Nylon & Terylene,
comparing thermoplastics, fibres and thermosets
6b.
Case study 3. Choosing a material for particular engineering applications
See also 5.
Case study 1. Properties
- choosing materials for car construction
(1)
Aircraft
fuselage and wings
You need a strong 'light' material.
Titanium and aluminium alloys are used.
(2)
Disposable coffee cup for a cafe chain (sit-in or takeaway AND
preferably recyclable)
The cup needs to be: not brittle, not
melt/deform when hot drank poured into it, thermally insulating so you
don't get burnt picking up the cup, cheap to produce in mass production.
Metals are good thermal conductors,
not very insulating! and not cheap to produce.
Ceramics are good insulators, but
heavy and brittle, can be re-washed but not really recyclable if broken,
too costly and not suitable as a takeaway object.
Composites are light, strong and
thermally insulating, but not recyclable and relatively expensive to
make.
Plastic is the best material, good
thermal insulators, cheap to produce in large quantities, maybe
recyclable, but you need a more thermally stable plastic than
poly(ethene) e.g. poly(propene).
However, there are big
environmental questions about the use of plastics as the levels of
plastic pollution are rising all the time, so, ....
a growing alternative is
paper-cardboard, this is thermally insulating, cheap to produce and
recyclable.
(3) The hull of a boat or ship
The material must be strong and
forged/bent into shape - steel good, will corrode, but can be
economically protected
e.g. with paint.
For larger boats and navy
vessels, much of the superstructure can be made of aluminium - less
dense and good anti-corrosion properties.
Small boats and yachts can be
fabricated from resin-fibreglass composites - waterproof and quite
strong and light. Carbon fibre composites are used too.
The material mustn't be porous or
brittle - ceramic no good
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7. Useful extra
reading on materials, their properties and uses
This page can't cover all the
materials or contexts you may come across on your course or in the exam,
so, for more on the uses of
materials where their use is related to their properties see ...
-
Polymerisation, plastics,
poly(ethene), poly(propene), uses, problems, recycling
-
Condensation polymers, Nylon & Terylene,
comparing thermoplastics, fibres, thermosets
-
Transition
Metals - properties and uses
-
Giant covalent structures and uses
-
Structure and properties of metals
-
Uses of carbon nanotubes
-
and checkout the
'smart/nano-materials' indexes on this page below.
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8. Nanochemistry and
Smart Materials Indexes
NANOCHEMISTRY
Part 1.
General introduction to nanoscience,
nanoparticles
and commonly used terms explained
Part 2.
NANOCHEMISTRY - an introduction and potential
applications
Part 3.
Uses of Nanoparticles of titanium(IV) oxide, fat and silver
Part 4.
From fullerenes & bucky balls to carbon nanotubes
Part 5.
Graphene and
Fluorographene
Part 6.
Cubic and hexagonal boron nitride BN
Part 7.
Problems, issues and
implications associated with
using nanomaterials
Word-fill quiz
"Aspects of nanochemistry"
SMART MATERIALS
Part 1
Chromogenic materials - Thermochromic, Photochromic & Electrochromic Materials
Part 2
Shape memory alloys e.g. Nitinol & Magnetic Shape Memory Alloys
Part 3
Shape memory polymers, pH and temperature sensitive-responsive polymers,
self-healing materials
Part 4
Lycra-Spandex
Part 5
High
performance polymers like kevlar
Part 6
Gore-Tex, Thinsulate and Teflon-PTFE
Part 7
Piezoelectric effect/materials & Photomechanical materials
Part 8
Carbon fibres
Word-fill quiz
"Designer Smart Materials"
All My synthetic
polymer-plastics revision notes pages
Introduction to addition polymers: poly(ethene), poly(propene), polystyrene, PVC,
PTFE - structure, uses
More on the
uses of plastics, issues with using plastics, solutions and recycling
methods
Introducing condensation polymers: Nylon, Terylene/PET,
comparing thermoplastics, fibres, thermosets
Extra
notes for more advanced level organic chemistry students
Polymerisation of alkenes to addition polymers - structure, properties, uses of
poly(alkene) polymers
The manufacture, molecular structure, properties and uses of
polyesters
Amides
chemistry - a mention of
polyamides
The structure, properties and uses of
polyesters and polyamides involving aromatic monomers
The chemistry of amides
including Nylon formation, structure, properties and uses
Stereoregular polymers -
isotactic/atactic/syndiotactic poly(propene) - use of Ziegler-Natta
catalysts
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