פולימרים

What would be the number average molecular weight of the polymer formed from the condensation polymerization of 6-aminohexanoic acid (MW131) and the cyclic amide caprolactam (MW 113) where from both nylon 6 if the reaction were carried out to 99.9% reaction conversion? (Choose from the following four possibilities)

1

מיין לפי

Free radical polymerization of olefins general forms polymers with a broad range of molecular weights. To overcome this and to form polyolefins having a narrow range of molecular weight by a free radical polymerization which of the following approaches has been successful?

1

מיין לפי

The difference in mechanical properties between low density polyethylene and high density polyethylene is due to which of the following? (Choose from the following four possibilities)

1

מיין לפי

Which of the following statements on polymerization mechanisms is correct? (Choose from the following four possibilities)

1

מיין לפי

Olefin polymers made by complex metal coordination catalysts generally can have better mechanical properties than the same polymers made by free radical or cationic polymerization. The reason for this is (Choose from the following four possibilities)

1

מיין לפי

The polydispersity of a particular polymer sample is 1.8 and the molecular weight (MW) determined by light scatter was 126,000 what MW would a membrane osmometry measurement determine?

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מיין לפי

If a polyvinylchloride (PVC) polymer sample elutes on a gel permeation chromatograph column at the same volume as a polystyrene sample that has a molecular weight of 20,000 and an intrinsic viscosity of 2.3 dL/g and the PVC polymer has an intrinsic viscosity of 4.8 dL/g what is the molecular weight of the PVC polymer sample?

1

מיין לפי

The following polymers were synthesized: (I) polyvinyl alcohol, (II) polyacrylonitrile, (III) polyamide and (IV) polyacrylic acid. What are the different types of inter-chain secondary interactions in each of the polymers? (Choose from the following four possibilities)

1

מיין לפי

A new polymer has been synthesized with the structure - (CH2-CHR)n- where R contains the groups of -C(=O), and -C6H5. The group attraction constants G [(cal cm3)1/2 mol-11 are for -CH2- is 133, and for -C=O it is 275, and for -CH-it is 28, and for -C6Hs it is 735. Using the equation for solubility parameters of polymers o[(cal cm)1/2] =DEG/M where M is the molecular weight 132, d is the density of 1.2 determine which of the following solvents will most likely dissolve the polymer? (Choose from the following four possibilities)

1

מיין לפי

Three different methods are used to determine molecular weight distribution by separating the different molecular weight fractions. These methods are Fractional solution (FS), fractional precipitation (FP) and gel permeation chromatography (GPC): Which of the following statements on the sequence in which the different molecular weights are separat d by each method is true? (Choose from the following four possibilities)

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מיין לפי

Discuss, Learn and be Happy דיון בשאלות

Free radical polymerization of olefins general forms polymers with a broad range of molecular weights. To overcome this and to form polyolefins having a narrow range of molecular weight by a free radical polymerization which of the following approaches has been successful?

The difference in mechanical properties between low density polyethylene and high density polyethylene is due to which of the following? (Choose from the following four possibilities)

Which of the following statements on polymerization mechanisms is correct? (Choose from the following four possibilities)

Olefin polymers made by complex metal coordination catalysts generally can have better mechanical properties than the same polymers made by free radical or cationic polymerization. The reason for this is (Choose from the following four possibilities)

The polydispersity of a particular polymer sample is 1.8 and the molecular weight (MW) determined by light scatter was 126,000 what MW would a membrane osmometry measurement determine?

The following polymers were synthesized: (I) polyvinyl alcohol, (II) polyacrylonitrile, (III) polyamide and (IV) polyacrylic acid. What are the different types of inter-chain secondary interactions in each of the polymers? (Choose from the following four possibilities)