Polymer deterioration by swelling may be reduced by which of the following? Increasing degree of crosslinking, increasing molecular weight, and decreasing degree of crystallinity Decreasing degree of crosslinking, decreasing molecular weight, and decreasing degree of crystallinity Increasing degree of crosslinking, increasing molecular weight, and increasing degree of crystallinity Decreasing degree of crosslinking, increasing molecular weight, and increasing degree of crystallinity

Polymer deterioration by swelling may be reduced by which of the following? Increasing degree of crosslinking, increasing molecular weight, and decreasing degree of crystallinity Decreasing degree of crosslinking, decreasing molecular weight, and decreasing degree of crystallinity Increasing degree of crosslinking, increasing molecular weight, and increasing degree of crystallinity Decreasing degree of crosslinking, increasing molecular weight, and increasing degree of crystallinity

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

( B ) A stress of 6.7 MPa is employed to one type of a polymer under constant strain . After 40 days at 20 ° C the stress is reduced to only 8.4 MPa . When the same polymer is heated to 40 ° C the relaxation time is 40 days . 1- Calculate the relaxation time constant for this material at 25 ° C ? 2- Estimate the stress after 50 days at 25 ° C ? 3- Estimate the stress relaxation activation energy for the same polymer .
For a given polymer, the activation energy for the stress relaxation was measured to be 59kj/mol. If the stress relaxation time for this polymer at 7 degree Celsius is 3150 seconds. What is the relaxation time at 110 degree Celsius
V. Using the figure/data below, answer the following questions for polystyrene: (a) What is the specific free volume at 120°C? (b) What is the specific free volume at 80°C? ag "24 x 104 1ºc OR "55x 104 10C Spacific Volume 100°C Temperature, OC
An unknown polymer sample was found to have the following molecular weight distribution: Molecular weight range xi 8,000 -20,000 0.05 20,000 - 32,000 0.15 32,000 44,000 0.21 44,000 56,000 0.28 56,000 -68,000 0.18 68,000 - 80,000 0.10 80,000 - 92,000 0.03 Having a DP=763, which of the following common polymers is this sample? Select one: wi 0.02 0.08 0.17 0.29 0.23 0.16 0.05 a. Polymethylmethacrylate with a monomer molecular weight of 100.121 g/mol b. Polyvinyl chloride with a monomer molecular weight of 62.498 g/mol c. Polycarbonate with a monomer molecular weight of 61.0168 g/mol d. Polypropylene with a monomer molecular weight of 42.08 g/mol e. Polystyrene with a monomer molecular weight of 104.15 g/mol
Polymer Engineering question: Explain doping process and why this process important for conductive polymer?
A 1.02den silk fiber has reached its maximum tenacity value. How many grams (force) would it take to rupture such fiber when dry? Provide your answer with two (2) decimal positions and no unit Answer:
For a given polymer, the activation energy for stress relaxation was measured to be 10 kJ/mol. If the stress relaxation time for this polymer at room temperature is 3,600 s, what would be the relaxation time at 100 ◦C?
An unknown polymer sample was found to have the following molecular weight distribution: Molecular weight range 8,000 - 20,000 20,000 - 32,000 32,000 - 44,000 44,000 - 56,000 56,000 -68,000 68,000 -80,000 80,000 - 92,000 Having a DP=763, which of the following common polymers is this sample? Xi 0.05 0.15 0.21 0.28 0.18 0.10 0.03 Wi 0.02 0.08 0.17 0.29 0.23 0.16 0.05 Select one: O a. Polymethylmethacrylate with a monomer molecular weight of 100.121 g/mol O b. Polystyrene with a monomer molecular weight of 104.15 g/mol Polycarbonate with a monomer molecular weight of 61.0168 g/mol O c. O d. Polyvinyl chloride with a monomer molecular weight of 62.498 g/mol Polypropylene with a monomer molecular weight of 42.08 g/mol O e.
Nowadays, many cooking utensils are made of polymeric materials. However, people believe that heating plastic utensils would cause harm such as releasing toxic substances. Hence, people are looking for other alternatives to replace plastic. Choose ONE cooking utensil (spatula) and identify the suitable material that will satisfy its criteria. Justify your answer. Your discussion must include the interrelationship between structure-properties-processing of the selected cooking utensil.
What are the strengths and weaknesses of this Visceoelastic model?
An unknown polymer sample was found to have the following molecular weight distribution: Molecular weight range Xi Wi 8,000 – 20,000 0.05 0.02 20,000 – 32,000 0.15 0.08 32,000 – 44,000 0.21 0.17 44,000 – 56,000 0.28 0.29 56,000 – 68,000 0.18 0.23 68,000 – 80,000 0.10 0.16 80,000 - 92,000 0.03 0.05 What would the weight average molecular weight of the sample be if, we had filtered the monomer mixture with a 44 kDa dialysis tubing before preparation? (Hint: a dialysis tubing of a known molecular weight, only keeps molecules larger than that size)
Connecting rod (as shown below) is a car part that connects engine piston to crankshaft and converts reciprocating motion into rotating motion. It performs under load at high temperature around 150°C. Long carbon fiber thermoplastic composite (LFT) with 30% carbon fiber has been considered to replace metal (steel or aluminum) rod to improve efficiency. Based on the data for different polymers listed in the table above, which polymer(s) would you choose as the polymer matrix for the connecting rod? What is your rationale?