Unformatted text preview: This means that the sliding in the chains is more difficult leading to higher strengths, higher stiffness, and high melting points. Because the stiffness is also affected it would not be ideal in grocery bags, because of the lack of flexibility. However, it is great for anything that requires high strength and resistance. 1. A stress of 1000 psi is applied to a polymer that operates at a constant strain: after 6 months the stress drops to 850 psi. For a particular application, a part made of the same stress of 900 psi after 12 months. What should be the original stress applied to the polymer for this application? a. Using the formula: i. σ=σ ℮(-t÷λ) 850=1000℮(26/λ) λ=26/(ln(0.1625) λ= 160 weeks 900=σ ℮(-52/160) 900=σ ℮(-0.325) 900=σ (0.723) σ =1246...
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This note was uploaded on 06/28/2011 for the course MSE 280 taught by Professor Dr.barryandrews during the Fall '10 term at University of Alabama at Birmingham.
- Fall '10