An unknown polymer sample was found to have the following molecular weight distribution:Molecular weight range8,000 - 20,00020,000 - 32,00032,000 - 44,00044,000 - 56,00056,000 -68,00068,000 -80,00080,000 - 92,000Having a DP=763, which of the following common polymers is this sample?Xi0.050.150.210.280.180.100.03Wi0.020.080.170.290.230.160.05Select one:O a. Polymethylmethacrylate with a monomer molecular weight of 100.121 g/molO b.Polystyrene with a monomer molecular weight of 104.15 g/molPolycarbonate with a monomer molecular weight of 61.0168 g/molO c.O d.Polyvinyl chloride with a monomer molecular weight of 62.498 g/molPolypropylene with a monomer molecular weight of 42.08 g/molO e.

Given:Molecular weight distribution tableDP = 763

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 X₁ 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

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 X₁ 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

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

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)
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
Q5 (a) Figure 6 shows two types of polymeric products fabricated using different processing techniques. Suggest with justification for the type of processes used to produce the products: i. Product A ii. Product B A B Figure 6. Two types of polymeric products (a) plastic bottles and (b) plastic car boot tray (b) The molecular weight data of a Polymer X are given in Table 3. Once undergone a melting process, it achieves degree of polymerization, DP of 498 upon solidification. i. Calculate the number-average molecular weight (Mn) for the polymer. ii. Calculate the molecular weight for monomers of the Polymer X. iii. Prove that the Polymer X is a polytetrafluoroethylene (PTFE) with chemical formula of (C2F4)n- Given the atomic weights for carbon, C is 12.011 g/mol and fluorine, F is 18.998 g/mol.
Question 5: The graph below gives a plot of force versus total sample length in a tensile test of a polymer. The sample is cylindrical, with an initial diameter of 1 cm and an initial length of 10 cm. From the data below, calculate the modulus, yield stress, yield strain, tensile strength, and % elongation. 1200 800 10 12 13 14 15 Lensth (cm) Force (N)
Q2/ Determine the weight and number average molecular weights as well as degree of polymerization for the polypropylene materials. Number Range of Molecular weight in gram/mol and weight fractions X₁ W₁ 8000- 16000 0.05 0.02 16000- 24000 0.16 0.1 24000- 32000 0.24 0.2 32000- 40000 0.28 0.3 40000- 48000 0.20 0.27 48000- 56000 0.07 0.11
d) A number of [0]s and [0,90]s CFRP test specimens were made from prepreg material with the following properties: Fibre strength, of = 3250 MPa Fibre modulus, E₁ = 195 GPa Matrix strength, m = 35 MPa Matrix modulus, Em = 3.8 GPa Volume fraction of fibres, Vf = 0.65 Calculate the tensile strength, oc, and the tensile modulus, Ec, in the 0° and 90° directions, using the simple "rule of mixtures" approach for both the [0]s and [0,90]s specimens.
9. A polymer sample with an original length of 10 cm and cross- sectional area of 1 cm² is subjected to a tensile test. The force applied to the sample is recorded at different elongations, and the following data is obtained: Force (N) Elongation (cm) 0 100 200 300 400 500 0 1 2 3 4 5 Using this data, calculate the modulus of the polymer sample in units of Pa.
A polymer has creep behaviour that can be represented as a power law equation: e = 0 (Jo + Jit") where J, is 0.5 GPa1, J1 is 0.45 GPa's 0.3 and n is 0.3 (with t in seconds). A component of this material has the following applied stress history: There is no stress before t = 0 A positive (tensile) stress of 8 MPa is applied from t = 0 for 4 hours From t = 4 hours to 6 hours, the stress is compressive stress of 2 MPa The stress is then removed. What will the strain in the material be at t = 9 hours? Enter your value as a number to 4 decimal places. You have a 2% error margin with this.
Compression molding is a manufacturing process in which the molding material is preheated then placed in an open mold cavity where the compressive action of the punch forces the polymer into the desired shape as shown in the figure below. Based on your understanding of the behavior of polymers, which of the statements below regarding compression molding of polymers are accurate? Punch Cavity C. -Upper mold half Charge 41 (1) -Lower mold half Knock-out pin V, F |x.F (2) and (3) Molded part a. Lower operating temperatures are more desirable as they reduce viscosity making it easier to fill the cavity b. This process can only be used for thermosets as they can thermally cure from monomer state This process can be used for both thermosets and thermoplastics as they can both be thermally shaped d. This process is suitable for rubber, PVC and polymethyl methacrylate
Question 2 Figure 2 shows the dependence of fatigue strength on testing cycles (S-N curve) of an acetal polymer. 60 50 40 30 20 10 104 105 106 107 108 Number of cycles to failure Figure 2 The S-N fatigue curve for an acetal polymer a. What is the fatigue strength, or maximum stress amplitude, at one million cycles of loading? b. An acetal polymer 30-cm-long bar with a diameter of 20 mm is designed to survive one million cycles of loading, what is the maximum allowable axial load that can be applied on one end of the bar? Magnitude of stress Reversal, MPa
Molecular weight data for some polymer are tabulated here. Compute (a) the number-average molecular weight, (b) the weight-average molecular weight. (c) If it is known that this material's degree of polymerization is 710, which one of the polymers listed in Table 14.3 is this polymer? Why? Molecular Weight Range g/mol 15,000-30,000 Xi Wi 0.04 0.01 30,000-45,000 0.07 0.04 45,000-60,000 0.16 0.11 60,000-75,000 0.26 0.24 75,000-90,000 0.24 0.27 90,000 105,000 0.12 0.16 105,000-120,000 0.08 0.12 120,000-135,000 0.03 0.05
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 0.03 Knowing that the monomer is methyl methacrylate, which of the below is the number average degree of polymerization for this polymer sample? Select one: O a. O b. DP 476 O C. DP = 338 DP = 664 O d. DP 544 O e. DP = 801 Xi 0.05 0.15 0.21 0.28 0.18 0.10 Wi 0.02 0.08 0.17 0.29 0.23 0.16 0.05