Polymers - Orthopaedic Biomaterials in Research and Practice - page 161

C. Low tensile strength
D. Efficient load transfer to bone
E. Exothermic reaction
ANSWER:
B .
PROBLEM 6.8
During the in vivo polymerization of PMMA (true or false),
1. The entire cement mass is converted from a low-molecular-weight
monomeric state to a high-molecular-weight polymer.
2. Incorporation of some blood and fluid is desirable to reduce peak
temperature reached.
3. Temperature elevation of surrounding tissue depends only on the
total amount of cement used.
4. The bond established between PMMA and bone is simply a
mechanical interlock.
5. Working time may be extended by prechilling components.
ANSWER:
F, F, F, T, T.
PROBLEM 6.9
Polyethylene, as used in joint replacements, is (true or false)
1. Low molecular weight
2. Made by condensation polymerization
3. Largely crystalline
4. A thermoset material
5. Ductile and tough
ANSWER:
F, F, T, F, T.
PROBLEM 6.10
An elastomer is a polymer (select the best answer[s])
A. With a high T G
B. With a low modulus and high ductility
C. With a large ε y
D. Containing silicon atoms
E. That has a large, recoverable elasticity