plastics Flashcards
(31 cards)
what is the difference between thermosetting and thermoforming plastics?
Thermoplastics can be repeatedly heated and moulded whereas thermosets will burn if reheated
What are Biodegradable Polymers?
Biodegradable polymers are eco-friendly materials that break down, unlike conventional oil-based polymers.
give two examples of biodegradeable polymers?
potatopak and corn starch polymers
What is a limitation of thermoplastics regarding heat and UV sensitivity?
Thermoplastics are not suitable for use in areas that require resistance to heat or UV light, as they can degrade under these conditions.
What are the characteristics of thermosetting plastics?
Hard and durable
Can withstand higher temperatures
What are the key benefits of injection moulding?
Ideal for producing complex, three-dimensional shapes and is suitable for large production runs.
What type of products is vacuum forming most commonly used for?
packaging
How does vacuum forming work?
plastic is heated and pulled over a mould using a vacuum. This process creates simple, non-complex shapes.
What are the advantages of vacuum forming compared to other plastic processing methods?
Vacuum forming has lower setup costs than processes like injection moulding, making it suitable for batch production and for producing cheaper products, like packaging.
What is blow moulding typically used for?
hollow products, such as bottles and containers, often with a narrow neck.
Why are thermoplastics not suitable for areas with heat or UV sensitivity?
because they soften and lose shape when exposed to high temperatures or UV light.
Why are Injection Moulding set-up costs considered high?
The moulds used are expensive
What is the benefit of using Injection Moulding in design?
allows for the creation of solid, complex components like handles and hinges that are integrated into the design, eliminating the need for additional fixings.
What is the advantage of using moulds in the Injection Moulding process?
results in high-quality, repeatable outcomes every time.
What type of products is Rotational Moulding used for?
Rotational Moulding is used to produce heavy-duty, seamless hollow products such as water tanks, traffic cones, kayaks, and storage tanks.
Why is the set-up cost for Rotational Moulding high?
moulds are expensive, making this process most suitable for batch or mass production.
how is blow moulding done?
molten plastic is extruded through the parison into the mould then is inflated with compressed air to fit the mould
What is the key feature of Extrusion Moulding?
Extrusion Moulding produces products with a continuous cross-section by forcing molten plastic through a die with the required shape.
what are the 6 R’s for sustainable design?
rethink, reuse, recycle, reduce, repair, refuse
What is the basic molecular structure of Elastomers?
Elastomers have long chain molecules that act like springs, allowing them to return to their original shape when distorted (stretched or compressed).
What makes Elastomers elastic?
The coiled molecular structure in Elastomers gives them their elastic properties, allowing them to stretch and return to their original form.
What are some examples of Elastomers?
artificial and natural rubber, neoprene (used for wetsuits and insulation), and silicone (used in medical devices and moulding).
How do Elastomers contribute to the design of wheels and tires?
Elastomers are used in wheels and tires for their flexibility, durability, and ability to provide a smooth, resilient surface that can withstand various stresses.
what is the common name for Acrylonitrile Butadiene Styrene?
ABS
