Fillers such as zinc oxide and carbon black are added to the crude natural rubber before vulcanisation in order to improve its_________________?

A. Polystyrene
B. Polyvinyl acetate
C. Polypropylene
D. Polyvinyl chloride-co-vinyl acetate

A. Saturated polyester
B. Polyurethane
C. Polystyrene
D. Either B. or C.

A. Higher melting point
B. Higher tensile strength
C. Lower density
D. None of these

A. Propylene
B. Phenol & formaldehyde
C. Phenol & acetaldehyde
D. Urea & formaldehyde

A. Polymethyl methacrylate (PMMA)
B. Polytetrafluroethylene (PTFE)
C. Polycarbonates
D. Phenolic resins