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Question:

What does the theoretical strength of the polymer include?

What does the theoretical strength of the polymer include?

Answer:

This can be considered in this way: remove a single macromolecule to stretch, how much power can make it pull off? It is clear that the energy needed to destroy this molecular chain should be equal to the bond energy that makes up the macromolecule main chain. For general organic polymers, this value is about 80 to 90 kg / mole, or 5 to 6 (10) ^ (- 12) lattice / bond. This energy can be simply seen as the function of the two atoms to overcome their mutual attraction f, the distance to the bond length d. In this way, according to the general G-G key length of 1.5A, can calculate the bond force:
F = E / d = 3 ~ 4 × (10) ^ (- 4) dyne / bond
The more precise calculation gives the strength of the macromolecular chain, which is about 2 ~ 5 × (10) ^ (-4) dyne / bond.
For a polymer, assuming that the macromolecules are neatly arranged, the 5 × (10) ^ (14) macromolecule chains will be added per square centimeter cross section, so that the tensile strength of the section will reach 25 × (10) ^ (10) ) Dyne / cm, or 25 × (10) ^ (4) kg / cm². This value is the highest theoretical strength value for the polymer. The actual strength of the polymer is only 1/10 to 1/100 of this value.

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