Compression Moudling Flashcards
What is compression moulding?
Compression moulding is when thermosetting plastics go through a process that involves high pressure, heat and time to make the product.
Are there more types of thermoplastics or thermosetting plastics?
There are many more types of thermoplastics.
What makes thermoplastics easier to work with than thermosetting plastics?
Thermoplastics are less rigidity than thermosetting plastics.
What is an important property of thermosetting plastics?
It has urea formaldehyde, which has a good electrical heat resistance, which makes it suitable for electrical products.
What material is placed into the cavity of the mould?
A preformed slug of materials, which is just compressed powder.
Why does the mould have to be heated?
The mould has to be heated to allow the molecules to cross link, which means making the long chain molecules in the polymer to join together.
After the mould is closed, why does it have to remain like that for a period of time?
This is to allow all the molecules to cross link in the plastic.
Why do you not have to wait for the plastic to cool before taking it out?
This is because it can’t change shape since the molecules are cross linked.
What are the advantages of compression moulding?
There is very little material that is wasted and moulds and machines are more inexpensive compared to injection moulding.
What are the disadvantages of compression moulding?
The preform need to be the right size before the process is started and in this process mainly simple and less detailed products are produced.
