lab 11 report

Discuss the reasons for the differences in glass transition temperature for the following pairs of polymers. Hint: check factors that affect Tg Polyethylene (-120°C) and polypropylene (-20°C)

Investigate and explain two experimental methods to measure the molecular ` weight distribution of polymers.

1. Component Container Stretch Wrap Pallet Product Material Polypropylene Polystyrene Wood Ca(OCI)2 Weight (kg/pallet) 48 0.5 15-18 725 Based on the above table, answer the following questions. (a) Discuss the possibility of fire at the calcium hypochlorite Ca(OCI)2 storage warehouse. Include your assumption on how the fire could spread in the storage warehouse. (b) Recommend solutions to avoid fire occur at the storage warehouse. (10) (10) (Total / Jumlah: 20 )

Calculate the number average molecular weight corresponding to the molecular weight distribution for the synthetic polymer sample fractionated in the graph below if the polydispersity index is 1.25

Plot the tensile strength of the polymers in table 16-2 as a function of the number of aromatic (benzene) rings in the monomer.

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Based on the answer to my question my follow-up question refers to processing. How does hydrogen bonding interactions affect the processing temperatures of these polymers? And what would we expect to occur? Why does hydrogen bonding affect thermal stabiltiy (thermo-oxidative stability) and affect degradation of the macromolecule. What is the mechanism of this interaction?

Determine phosphate concentration of a water sample using the following information: Standard curve- slope: 1763.2 y-int: 0.011806 R^2: 0.99181 Absorbance of water sample: 0.013

Discuss the reasons for the differences in glass transition temperature for the following pairs of polymers. Hint: check factors that affect Tg Poly(ethylene oxide) (-41°C) and Poly(vinyl alcohol) (85°C)

6.) An unknown polymer sample is fractionated, and the following molar fractions are obtained. Calculate Mn and Mw and the dispersity. Fill out the table to show your work. Fraction # 1 2 3 4 5 6 n₁ (mol) 0.004 0.011 0.009 0.003 0.017 0.008 M; (g/mol) 10,400 12,080 13,950 16,700 18,150 20,000 n¡Mi n;M;²

- & Sketch New · C $ 7 ♡ www 1500 kg/m³ O 3000 kg/m³ 5000 kg/m³ 7000 kg/m³ 9000 kg/m³ 44 < HD E Material X has an atomic radius R = 0.125 nm, an atomic weight of A = 51 g/mol, and a body centered cubic (BCC) crystal structure. Calculate the mass density of this material. Hint: Do your calculations in SI units, as this will help avoid numerical errors from unit conversions. Choose the answer closest to your calculated value.

Which of the following statement/s is/are true for the polymerization mechanisms? I. In both condensation and addition polymerization, the same mechanism operates throughout polymerization. II. In addition polymerization polymerization is necessarily initiated using initiator, but it is not necessary in condensation polymerization. II. In condensation polymerization all monomers are rapidly consumed at the early stage of the reaction, but some monomer remains even at long reaction time in addition polymerization. IV. In both condensation and addition polymerization, average molecular weight increases with increasing reaction time. A I and II B Il and II III and IV D II, II and IV

Discuss the reasons for the differences in glass transition temperature for the following pairs of polymers. Hint: check factors that affect Tg Poly(ethyl acrylate) (-24°C) and Poly(methyl methacrylate) (105°C)

Crud Chemicals is producing a casting resin that can be made using either (i) AA and BB monomers or (ii) an AB-type monomer {A & B represent different functional groups, like alcohol and carboxylic acids). A catalyst is added to promote polymerization in the mold. The material has many useful properties, but is deficient in heat and solvent resistance. A proposal is made to improve heat and solvent resistance by adding a tetrafunctional monomer (A4) to the mix to provide crosslinks. Unfortunately, no one in-house knows if this will work, or if the added A4 will form a gel, so they call you in as a consultant. Evaluate their idea to use A4 as a crosslinking agent for both types of polymerizations (i and ii).