This set of Applied Chemistry Multiple Choice Questions & Answers (MCQs) focuses on “Compounding of Plastics – 1”.
1. Usually the polymer resin is mixed with four to ten ingredients during the fabrication to impart useful properties to the finished articles. This is called mix.
Explanation: Usually the polymer resin is mixed with four to ten ingredients during the fabrication to impart useful properties to the finished articles. This is called mix. They are must and should to get good plastic.
2. __________ acts as a binder in plastics.
Explanation: Resins acts as the binders in plastic which holds the different constituents together. The product of polymerisation is called resins.
3. ___________ increases the flexibility of the polymer.
Explanation: Plasticizers are used to increase the flexibility of the polymer. It is also used to the increase of plasticity of the polymer.
4. Plasticizers are used to get the ___________ between the polymeric molecules.
b) Freedom of movement
d) Sigma bond
Explanation: Plasticizers are used to get the greater freedom of movement between the polymeric molecules. Plasticizers neutralise the intermolecular forces of attraction between polymer chains.
5. Plasticizers ___________ the strength of the plastics.
c) Do not affect
d) May increase above the room temperature
Explanation: Plasticizer decreases the strength of the plastics. They also decrease the chemical resistance of the plasticizers.
6. __________ makes the polymers impermeable to x-rays.
a) Strontium salts
b) Ammonium salts
c) Calcium salts
d) Barium salts
Explanation: The barium salts makes the polymers impermeable to x-rays and asbestos provides heat and corrosion resistance to polymers.
7. The percentage of the fillers is up to ___________ total moulding mixture.
Explanation: The percentage of the fillers is up to the 50% of the total moulding mixture of the plastics. They reduce the cost of the polymers.
8. Which of the following are used as the fillers?
a) Vegetable oils
c) Ester of stearic acids
d) Wood flour
Explanation: Vegetable oils, camphor and ester of stearic acids are used as the plasticizers. The wood flour, ZnO, PbO are used as the fillers.
9. __________ prevent moulded article from sticking to the fabrication equipment.
Explanation: Lubricants prevent moulded article from sticking to the fabrication equipment. They impart flawless and glossy finish to the products.
10. Lubricants are used to prevent the moulded article from _________
c) Not sticking
Explanation: Lubricants are used to prevent the moulded article from sticking to the fabrication equipment. Lubricants make the moulding plastics easier.
11. Which of the following are not used lubricants?
Explanation: The most commonly used lubricants are oils, waxes, oleates, stereates and soaps. The salts are not used as lubricants.
12. ___________ is used to improve the thermal stability during polymerisation.
b) Colouring materials
Explanation: Stabilizers are used to improve the thermal stability during polymerisation. Accelerators are used to increase the polymerisation of fusion resin during modulation operation into linked infusible form.
13. Which of the following is a stabilizer?
a) White lead
d) Metallic oxides
Explanation: The PbO, ZnO and metallic oxides are used as the fillers. ZnO and metal oxides are also used as the accelerators. The stabilizers are white lead, lead chromate, red lead.
14. Compression moulding is applicable to ___________
a) Thermoplastic resins
b) Thermo setting resins
c) Both thermo plastic and thermo setting resins
d) Neither thermo plastics nor thermo setting resins
Explanation: Compression moulding is applied to both the thermo plastics and thermo setting resins. It is the one of the method of fabrication.
15. How many types of fabrication methods are there?
Explanation: There are seven types of fabrication methods are there. They are compression moulding, injection moulding, transfer moulding, extrusion moulding, bubble moulding, casting and thermoforming.
Sanfoundry Global Education & Learning Series – Applied Chemistry.
To practice all areas of Applied Chemistry, here is complete set of 1000+ Multiple Choice Questions and Answers.