AQA ------ Energies, Materials, Systems and Devices Flashcards
- Modern Materials - Smart Materials - Composite Materials and Technical Textiles
What is a modern material?
A new invention or one that has been recently discovered.
What are Biodegradable Polymers made from?
Vegetable Starches usually Corn-Starch
What are common Biodegradable polymers and a use for each?
- (PLA) = Polylactic Acid, used for 3D Printing Filament.
- (PHB) = Polyhydroxybutyrate / Biopol, used for plastic products.
- (PCL) = Polycaprolacoane / Polymorph, used for manufacturing aawkward shaped such as ergonomics.
What is Polymorph?
An item which can take multiple forms.
At what temperature does poly-morph and cool-morph melt?
Poly-Morph - 62 degrees
Cool-Morph - 42 degrees
Titanium is an element, it is commonly mixed with other alloys; why?
^ It is relatively lightweight, tough and stiff with a low density.
^ It has excellent corrosion resistance making it very versatile.
^ Titanium does not react with the human body
What is fibre optic and what are its uses?
Fibre optic cables carry light down a thin glass core, the uses of it are cable TV and broadband infrastructure, endoscopes and microelectronics and novelty goods.
What is Graphene?
It was accidentally discovered in 2004, it is one atom thick and has strength 200x steel, it is flexible, transparent, impermeable and highly electrically conductible.
How small are nano-materials
They are around the same size as a DNA molecule, they range from 1 to 1000 nano-metres.
How is metal foam created?
Gas is injected into liquid aluminium or titanium
What are smart materials?
They are materials which change properties and characteristics to respond to external stimulus.
What does a thermochromic material react to?
Thermal changes in the enviroment.
What does a photochromic material react to?
Ultra-Violet light changes in the enviroment.
What does a hydrochromic material react to?
Water (moisture) changes in the enviroment.
What does a piezoelectricmaterial react to?
Movement, stress ore electricity changes.
What does litmus paper react to?
pH changes
What does shape memory alloy (SMA) react to?
Heat or electricity
What does polycaprolactone react to?
Heat
What does Quantum Tunnelling Composite react to?
Pressure
What does nanomaterial react to?
Various stimulus
What are the types of reinforced plastic?
GRP & CRP
What is GRP?
Glass Reinforced Plastic
What is CRP?
Carbon Fibre Reinforced Plastic
What is Gore-Tex?
A waterproof yet breathable fabric membrane
How does Gore-Tex work?
It has 150 million holes per cm^2
- This means water droplets are too big to pass through.
- Perspiration an still escape in the form of water vapour.
What is an Aramid?
Aramids are particularly tough fibres made from modified polymide.
What do Aramids offer?
- Cut and tear resistance
- Flame proofing
- Thermal insulation
- High strength
- A hard wearing finish
What is the name for an Aromatic Polymide?
An Aramid
How big is a microfibre?
Less than one denier thick - one fifth the width of a human hair.
What are the disadvantages of microfibre?
- Flammable unless treated
- Synthetic and not renewable
- Takes many years to decompose
- Growing evidence relating it to oceanic polution
