Types of plastics
Plastics are used a lot in our daily life, from the moment we wake up in the morning, we start using different items formed with plastics. For example: the tooth brush handle, plates, bottles, lunch boxes, water purifiers, laptops and so many other articles! The list would be endless! So, even they are different all theses items are made up of plastic.
How is that possible? it is possible because plastic can have different forms.
Plastic is a polymer, and every polymer is a long chain of repeated monomers, these monomeric units in different plastics are arranged in a different way. They could be linearly arranged or They inter-link together in a cross linked manner.
The difference in the monomeric unit is also another reason to obtain different forms of plastics. However, plastics are usually classified in two major categories: Thermosetting Plastics and thermoplastics.
To differentiate between these two types, let’s take two commonly used examples. The first one is the handle of the frying pan while the second example is a simple water bottle. When we heat these two materials formed of plastic, the bottle will melt, but the handle will just heat up without melting.
Both are both made of plastic, then why is there so much difference? This is because they are made of two different types of plastics! The first one which makes up the handle is called the thermosetting plastic. While the other type is thermoplastic.
The difference between Thermosetting plastics and Thermoplastics
Looking at the given examples, we can deduce that the difference appear after heating.
Thermosetting plastics do not melt on heating. While manufacturing the particular article, the plastic take a permanent form, it cannot be reformed or remoulded later. The two most commonly used examples of thermosetting plastics are Melamine and Bakelite. Melamine can support a big amount of heat, it is used for the kitchenware. Bakelite is used in making handles of kitchen utensils and switches because it doesn’t conduct heat and electricity.
By heating thermoplastics turn to soft, so they can be moulded or simply melted on heating. they also can be changed into different forms. At room temperature, they are available in the form as Solids.
A thermoplastic is a plastic material that becomes mouldable above a specific temperature and solidifies upon cooling. Polythene and PVC are the most common examples of thermoplastics.
Where do we use Polythene? It is used to form bags and adhesive tapes and many other substances.
polythene is used in various forms. And PVC is Polyvinyl chloride, it comes in two distinct forms. The first one is hard or rigid, it is used to form strong structures like construction pipes… The other type is soft PVC which is used for making containers and bottles used daily.