Out of all the elastomers, natural rubber has the longest elongation range & flexibility of the order of _______________ percent?
A. 1-1000
B. 1000-1500
C. 1500-2000
D. 2000-2500
Polymer Technology
Addition polymerisation takes place either by a free radical mechanism or ionic mechanism depending on the reagents used. Free radical polymerisation is catalyzed by _______________, which decompose to give free radicals?
Addition polymerisation takes place either by a free radical mechanism or ionic mechanism depending on the reagents used. Free radical polymerisation is catalyzed by _______________, which decompose to give free radicals?
A. Organic peroxides
B. Sulphuric acid
C. Hydrofluoric acid
D. None of these
The monomer of poly vinyl chloride (PVC) is__________________?
The monomer of poly vinyl chloride (PVC) is__________________?
A. Chloroethane
B. Ethylene dichloride
C. Ethyl chloride
D. Chloroform
In nylon-66, the first and second numbers (i.e., 6) respectively designate the number of carbon atoms present in the_________________?
In nylon-66, the first and second numbers (i.e., 6) respectively designate the number of carbon atoms present in the_________________?
A. Hexamethylene diamine and the ring
B. Hexamethylene diamine and the adipic acid
C. Adipic acid and the ring
D. None of these
_____________ is not a polyester fiber?
_____________ is not a polyester fiber?
A. Terylene
B. Dacron
C. Nylon
D. Polyacrylonitrile
Neoprene is rendered non-inflammable, because of_____________________?
Neoprene is rendered non-inflammable, because of_____________________?
A. Its cross-linked structure
B. Its linear chain structure
C. The presence of chlorine atoms in its monomer
D. The absence of chlorine atoms in its monomer
Thermosetting polymers as compared to thermoplastic polymers_____________________?
Thermosetting polymers as compared to thermoplastic polymers_____________________?
A. Are formed by addition polymerisation
B. Have three dimensional structure
C. Have linear structure
D. None of these
Alkyd resin e.g., glyptal resin formed by Phthalic anhydride and glycerine is not used_______________?
Alkyd resin e.g., glyptal resin formed by Phthalic anhydride and glycerine is not used_______________?
A. For surface coating of automobiles & air crafts
B. For fibre making
C. As plasticiser for PVC & nitrocellulose
D. For film forming materials
Orion is_________________?
Orion is_________________?
A. A copolymer
B. A condensation polymer
C. Obtained by polymerising vinyl cyanide
D. All A., B. and C.
Temperature and gage pressure maintained during the manufacture of cold SBR (styrene butadiene rubber) are__________________?
Temperature and gage pressure maintained during the manufacture of cold SBR (styrene butadiene rubber) are__________________?
A. 5°C and 1 kgf/cm2
B. – 20°C and 1 kgf/cm2
C. 0°C and 1 kgf/cm2
D. 0°C and 3 kgf/cm2