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Chemical Engineering :: Polymer Technology

  1. Vulcanisation of rubber

  2. A.
    decreases its tensile strength.
    B.
    increases its ozone & oxygen reactivity.
    C.
    increases its oil & solvent resistance.
    D.
    converts its plasticity into elasticity.

  3. Teflon is

  4. A.
    phenol formaldehyde
    B.
    an inorganic polymer
    C.
    polytetra florouethylene (PTFE)
    D.
    a monomer

  5. __________ is produced by polymerisation of chloroprene.

  6. A.
    Thiokol (a polysulphide rubber)
    B.
    Butyl rubber
    C.
    Neoprene
    D.
    Polyurathane rubber

  7. Polyvinyl chloride (PVC) is

  8. A.
    a thermosetting material.
    B.
    a condensation polymerisation product.
    C.
    made by employing emulsion polymerisation.
    D.
    none of these.

  9. Pick out the wrong statement regarding the solubility characteristics of high polymers.

  10. A.
    Greater the degree of cross-linking in the polymer, lesser is its solubility.
    B.
    Polymers having more aliphatic character are more soluble in aliphatic solvents, while those polymers having more aromatic character are more soluble in aromatic solvents.
    C.
    Swelling tendency or solubility of polymers in a particular solvent decreases with increase in molecular weight of the solvent.
    D.
    High molecul ar weight polymers on dissolving gives solution of very low viscosity.

  11. Ebonite is a/an

  12. A.
    highly vulcanised rubber.
    B.
    natural rubber.
    C.
    unvulcanised raw rubber.
    D.
    adhesive.

  13. Elastomers are

  14. A.
    thermosetting material.
    B.
    exemplified by protein derivatives.
    C.
    having high flexural strength.
    D.
    having very high tensile strength and heat resistance.

  15. Which of the following additives are added to plastics to make it impervious to X-rays ?

  16. A.
    Asbestos
    B.
    Barium salt
    C.
    Carborundum
    D.
    Phthalic acid

  17. Paper like thin plastic articles can be produced by

  18. A.
    blow moulding
    B.
    vacuum thermo forming
    C.
    injection moulding
    D.
    none of these

  19. Addition polymerisation takes place either by a free radical mechanism or ionic machanism depending on the reagents used. Free radical polymerisation is catelyzed by __________ , which decompose to give free radicals.

  20. A.
    organic peroxides
    B.
    sulphuric acid
    C.
    hydroflouric acid
    D.
    none of these