A. Bakelite is a thermosetting polymer.R. It can be melted again and again without any change.Both A and R are correct and R is the correct explanation of the AA is correct but R is incorrectBoth A and R are correct but R is not the correct explanation of (2024)

FAQs

Can Bakelite be melted again and again without any change? ›

So the polymer mass becomes infusible. It is not possible to get back the original shape after melting. Hence, it cannot be reused. Hence, the bakelite polymer cannot be melted again and again without any change.

Bakelite is a thermosetting polymer which are cross linked or heavily branched molecules, which on heating undergo extensive cross-linking in moulds and again become infusible. This can not be reused means it can't regain their original shape after melting.

They become soft at high temperatures and melt. They cannot be heated as they are very good conductors of heat.

Thermoplastic can be moulded to the desired shape again and again where thermosetting plastics will not change its shape on heating.

Bakelite is a thermoset polymer and decomposes rather than melting. The precursor is liquid, but once the reaction is complete can't be remelted.

Solution: Bakelite is an example of thermosetting plastic because once it is heated it converts into infusible mass and cannot be remoulded or reshaped on heating.

Hence, option is correct. Bakelite can be melted again and again without any change. Bakelite is a thermosetting polymer.

By the late 1940s, newer materials were superseding Bakelite in many areas. Phenolics are less frequently used in general consumer products today due to their cost and complexity of production and their brittle nature.

There are however a few companies left who are still manufacturing Bakelite products, for use in applications requiring resistance to heat, electricity and chemicals. Some of these applications include: – Electrical components such as switchboards, panels and sockets for light bulbs.

Polymers within the material cross-link during the curing process to perform an unbreakable, irreversible bond. This means that thermosets will not melt even when exposed to extremely high temperatures. Common examples of thermoset plastics and polymers include epoxy, silicone, polyurethane and phenolic.

Can thermosetting polymers be melted and recycled? ›

While soft thermoplastics can be highly recyclable, thermoset polymers—used in applications in the automotive, aerospace and wind industries that require strength and light weight—are built to be durable and cannot be recycled easily by conventional methods, such as by being dissolved in a solvent or melted.

On the other hand, thermoset polymers form a crosslinked structure during the curing process, preventing them from being melted and remoulded. As an analogy, think of thermosets like concrete, once they have set, they can never go back to the liquid form (irreversible process).

What are thermoplastics? They are molten when heated and harden upon cooling. These characteristics, which lend the material its name, are reversible so that it can be reheated, reshaped, and frozen repeatedly. As a result, thermoplastics are mechanically recyclable.

Thermoplastic polymers are materials made up of linear molecular chains. These polymer chains can be melted and reformed. This makes them ideal for applications where they need to be molded or shaped, such as injection molding.

Thermoset materials, on the other hand, can neither be reused nor recycled. Because of the cross-linked bonds in thermoset materials, they cannot be remelted and reformed.

Bakelite is a type of plastic that cannot be softened and melted on heating.

Properties: Thermosetting: Unlike some plastics which can be melted multiple times, Bakelite, once set, cannot be remelted or remoulded. Electrical Non-conductivity: This made it highly useful in the electrical and automotive industries as an insulator.

Thermosetting plastics cannot be remoulded or reshaped on heating. Bakelite, melamine, and polyester are few examples of thermosetting plastics.

Abstract: Bakelite is a 3-dimensional cross-linked network structured thermosetting polymer which is difficult to recycle after use. However, it contains high levels of carbon and CaCO3 that can be recovered for use as reductant and fluxing agent in ironmaking.