Which of the following is a thermosetting polymer?
- Buna-N
- PVC
- Bakelite
- Nylon 6
The Correct Option is C
Solution and Explanation
Bakelite is a thermosetting polymer, meaning it undergoes irreversible chemical reactions during its curing process to form a hard, infusible, and insoluble material. Once molded and cured, Bakelite cannot be softened or reshaped by heating, making it suitable for applications requiring high heat and chemical resistance, such as electrical insulators and durable handles for cookware.
So, the correct option is (C): Bakelite.
Top Questions on Polymers
- A polymer melt being extruded through a spinneret hole of circular cross-section exhibits a die-swell ratio of 2.2. The extrusion velocity and volumetric flow rate during this extrusion process are 20 m/min and \(2.6 \times 10^{-8}\) m\(^3\)/s, respectively. The maximum diameter (mm) of the extruded melt after exit from the spinneret hole (rounded off to 2 decimal places) is:
- Determine the correctness or otherwise of the following Assertion [p] and Reason [r].
[p]: The tenacity of a polymeric fibre depends on the strain rate
[r]: Under mechanical deformation polymeric fibre exhibits both elastic as well as viscous response - Amongst the following, the exothermic transition(s) is/are:
- The fibre forming polymer which contains aromatic group in the main chain is:
- The fibre which does NOT contain 1,4-glycosidic bonds is
Questions Asked in JEE Main exam
If all the words with or without meaning made using all the letters of the word "KANPUR" are arranged as in a dictionary, then the word at 440th position in this arrangement is:
- JEE Main - 2025
- permutations and combinations
If the system of equations \[ x + 2y - 3z = 2, \quad 2x + \lambda y + 5z = 5, \quad 14x + 3y + \mu z = 33 \] has infinitely many solutions, then \( \lambda + \mu \) is equal to:}
- JEE Main - 2025
- Calculus
- An electric dipole of mass \( m \), charge \( q \), and length \( l \) is placed in a uniform electric field \( E = E_0 \hat{i} \). When the dipole is rotated slightly from its equilibrium position and released, the time period of its oscillations will be:
- JEE Main - 2025
- Electric Dipole
The equilibrium constant for decomposition of $ H_2O $ (g) $ H_2O(g) \rightleftharpoons H_2(g) + \frac{1}{2} O_2(g) \quad (\Delta G^\circ = 92.34 \, \text{kJ mol}^{-1}) $ is $ 8.0 \times 10^{-3} $ at 2300 K and total pressure at equilibrium is 1 bar. Under this condition, the degree of dissociation ($ \alpha $) of water is _____ $\times 10^{-2}$ (nearest integer value). [Assume $ \alpha $ is negligible with respect to 1]
- JEE Main - 2025
- Law Of Chemical Equilibrium And Equilibrium Constant
- The distance of the point \( P(1, 2, 3) \) from the plane \( 3x - 4y + 12z - 7 = 0 \) is:
- JEE Main - 2025
- Geometry and Vectors
Concepts Used:
Polymers of Commercial Importance
- Polypropene is formed by the repetitive joining of propene. Propene is the monomer of Polypropene. It is used in the preparation of different materials like fibres, ropes, pipes etc.
- Polystyrene is formed from aromatic hydrocarbons, styrene is its monomer. It is used as a wrapping material to provide coverage to important materials, cabinets of television, in making radios.
- Polyvinyl Chloride (PVC) is formed by combining a large number of molecules of vinyl chloride. Vinyl chloride is its monomer. It is used in making raincoats and especially in water pipes.
- Glyptal is a synthetic polymer that is formed by monomers of Ethylene glycol and Phthalic acid. It is used in the manufacturing of paints, fabrics, lacquers etc.
- Bakelite is known as Polyoxybenzylmethylenglycolanhydride. Phenol and Formaldehyde are used as monomers to produce bakelite which is formed by the condensation reaction of these monomers.
- Natural Rubber is composed of polyisoprene molecules linked together to form an elastomeric structure. Natural rubber is used for various purposes like making tyres, rubber bands, lid grippers etc.
- Polypropylene is a hydrocarbon polymer that has a linear structure. It is a multifaceted polymer as it has properties of plastic as well as fibre and hence is used for multi-purposes. Propylene is the monomer of polypropylene.
- Polyethylene Terephthalate also termed PET is a thermoplastic polymer. Ethylene glycol and terephthalic acid are used in the preparation of Polyethylene Terephthalate and in making different things like containers for packing food and drinks.
- Polytetrafluoroethylene also termed PTFE is a fluoropolymer. It is slippery in nature and is highly resistant to heat. The monomer of polytetrafluoroethylene is tetrafluoroethylene.
Neoprene is formed from chloroprene. It is prepared by free radical polymerisation. The monomer of neoprene is chloroprene. It is used for preparing gaskets, conveyor belts etc.