Nanoparticles Flashcards
what are nanoparticles
really tiny particles around 1-100 nanometers diameter and a few hundred atoms
compare nanometers to ‘‘other things’’
they are bigger than atoms and simple molecules but smaller than everything else
what is the conversion of nanometer to micrometer
divide by 1000
explain the whole nanometers have high SA:V ratio
as particles decrease in size the surface area increases
nanoparticles have high surface area which enables them with different properties such that larger particles don’t have as greater proportion of atoms interact with substances
tell me 3 features of properties
- huge surface area:volume so good catalyst as more reactions take place on surface so bigger the surface area more collisions so faster rate of reaction
- new cosmetics such as sunscreen provide better protection and don’t leave white marks
- nano medicine = tiny fullerenes are absorbed by body easier so delivering drugs can be don’t conveniently
- lubricant coatings
- conduct electricity as tiny electric circuits built into computer chips
- added to plastics for durability and strength with out increasing mass
- silver nanoparticles added to polymer fibres to make surgical masks giving fibres antibacterial properties
what are the risks involved in using nanoparticles
- we are unaware fully of the affects it has
so must be tested properly - worried about the harmful affects and side effects on health
- some nano particles may not even break down and build up instead so can cause lung inflammation
what are the four type of material
ceramics , polymers , composites and metals
what are glass ceramics
- properties and uses of them
- method of making it
Transparent and strong, glass insulates against heat
Glass ceramics are also more durable than other materials hence they are better suited for use in windows than plastic
Most of the glass produced is soda-lime glass which is made by heating a mixture of limestone, sand and sodium carbonate (soda) until it melts
On cooling it solidifies to form glass
what is clay ceramics
- properties
- how made
- uses
These are hardened materials that resist compression
Clay is a soft material dug up from the earth from decomposed rock which hardens at high temperatures and when it is fired, produces a very strong and hard material
This allows bricks to be used to build walls which withstand the weight and pressure of the material bearing downwards on itself
what are polymers
- what is it
- properties
Can be tailor designed to have specific properties for specific uses:
stronger stretchier easily moulded
Usually tough and flexible, some specialist polymers can be brittle
Poor conductor of heat and electricity
cheap less dense
what are composites
what are they
quality of it
properties
made of material embedded into another material
- reinforcement and matrix
properties depend on material as they are tailored to needs
expensive
strong and light good for aerospace and sport cars manufacturing
what are metals
properties
what can they do
corrosion
Shiny, malleable and ductile so can be hammered into different shapes
Can be mixed with other elements to form alloys, which have different properties to the elements they contain
corrosion resistant metals can be produced which last longer than other metals
what are polymers good for
good thermal and electrical insulators As they are poor conductors of heat and electricity
insulating electrical wiring as they prevent electric shocks and overheating
what are composites good for
used in aviation, aeronautics and for making professional racing bicycles because of strong and low weight
what are metals good for
electrical cabling and in electronics due to their ability to conduct electricity
Copper is the most frequently used as it is a good conductor and is very malleable and easy to thread into cables
Aluminium is a very strong metal but is also very light
