Polymerization of thermoplastics is done by Addition mechanism B. Vulcanization
ID: 1021820 • Letter: P
Question
Polymerization of thermoplastics is done by Addition mechanism B. Vulcanization mechanism C. Condensation mechanism D. None of the above Byproduct forms in which one of the following polymerization mechanisms? Addition mechanism B. vulcanization mechanism C. condensation mechanism D. None of the above Mers of Teflon is given as B. C. D. None of the above nylon is and has high a thermoplastic - ductility B. a thermoset - strength C. an elastomer - ductility D. a composite - strength Natural rubber is a thermoplastic B. a thermoset C. an elastomer D. None of the above Which one of the following polymers has a benzene ring in its molecular structure and is used as insulation foam? Polyethylene (PE) B. Polyvinyl chloride (PVC) C. Polypropylene (PP) D. Polystyrene (PS)Explanation / Answer
1.d. none of the above, since thermoplastic Thermoplastics are high molecular weight polymers which contain very few or no crosslinks. Intermolecular forces, mostly van der Waals forces of attraction and physical entanglement help the polymer's monomeric units stick together.
2. Byproducts form in c. condensation mechanism. Since, in condensation there is always a leaving group or a loss of molecule that helps to have the entropy in favour of the polymerization process.
3. Teflon stands for poly-tetrafluroethylene, hence its mers are described by the formula c.
4. Nylon is a thermoplastic and has high ductility.
5. natural rubber is c. an elastomer because it has both viscosity and elasticity but almost no intermolecular forces.
6. D. Polystyrene(PS) has the benzene ring in its structure and used in insulator. The molecular formula of the monomer unit styrene is Ph-CH=CH2, i.e. it contains benzene ring. Hence, the polymer obviously contains the benzene ring in the formula.