For thermoplastic polymers, factors that favor brittle fracture are( ).
A. a reduction in temperature
B. an increase in strain rate
C. the presence of a sharp notch
D. increased specimen thickness
E. modifications of the polymer structure.
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The molecular characteristics that are essential for elastomers are( ).
A. they must be amorphous, having chains that are extensively coiled and kinked in the unstressed state
B. there must be some crosslinking
C. increased specimen thickness
After implantation, biodegradable polymers gradually decompose or ______ and their constituents are removed from the body as a result of normal metabolic processes.
Thermoplastic elastomers (TPEs or TEs) are a type of polymeric material that, at ambient conditions, exhibits elastomeric (or rubbery) behavior yet is ______ .
Polymerization is the process by which ______ are linked together to generate long chains composed of repeat units.