פולימרים

If a condensation polymerization is carried out with equal molar quantities of carboxyl and hydroxyl groups from a difunctional carboxylic acid monomer (two carboxylic groups), and from a tetra functional polyhydroxy monomer (four hydroxy groups), such that a crosslinked gel forms at a given point of monomer conversion what will be the approximate reaction conversion, p, of monomers into polymer at the gelation point.

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Amylose and cellulose are both polymers of glucose but have very different physical and mechanical properties. Cellulose is mechanically strong and insoluble in water and many other solvents. Amylose starch is water soluble and mechanically weaker compared to cellulose. Of the following which is the best explanation for these properties: (Choose from the following 4 possibilities)

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If a free radical polymerization is carried out with vinyl monomer 1 (H2C=CHR1) and vinyl monomer 2 (H2C=CHR2) where R1 can resonance stabilized a forming radical and R2 cannot resonance stabilize a radical what would you expect reactivity ratio r1=k11/k12 to be?

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Atom transfer polymerization is similar to which of the following polymerization processes with respect to the ratio of number average molecular weight to weight average molecular weight (Mn/Mw) it can achieve?

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If i have a polymer with a solubility parameter of 11.6 and in one case I want to make blend 1 with another polymer where the final mixture has two different glass transition points (Tg) and in the second case I want to make 2 with another polymer where the blend has only one Tg's what should be the solubility parameters of the second polymer in each case.

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Both liquid crystalline aromatic polyamides and linear high molecular weight polyethylene can be extrudes into fibers with tensile strengths higher than steel. The reason for this is (Choose from the following four possibilities)

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Characteristics of tensile stress-strain behavior for fibers, plastics & elastomers - distinction between. Which of the following statements is not correct? (Choose from the following four possibilities)

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Choose the secondary interactions in the polymers I) polyethylene, II) polyamide, III) Polyester, IV) Polyacrylic acid sodium salt: (Choose from the following four possibilities)

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condensation polymerization reactions such as polyamide or polyester polymerization are classified as stepwise reaction processes because (Choose from the following four possibilities)

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condensation polymerization reactions are classified as stepwise reaction processes because (Choose from the following four possibilities)

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Discuss, Learn and be Happy דיון בשאלות

If a free radical polymerization is carried out with vinyl monomer 1 (H2C=CHR1) and vinyl monomer 2 (H2C=CHR2) where R1 can resonance stabilized a forming radical and R2 cannot resonance stabilize a radical what would you expect reactivity ratio r1=k11/k12 to be?

Atom transfer polymerization is similar to which of the following polymerization processes with respect to the ratio of number average molecular weight to weight average molecular weight (Mn/Mw) it can achieve?

Both liquid crystalline aromatic polyamides and linear high molecular weight polyethylene can be extrudes into fibers with tensile strengths higher than steel. The reason for this is (Choose from the following four possibilities)

Characteristics of tensile stress-strain behavior for fibers, plastics & elastomers - distinction between. Which of the following statements is not correct? (Choose from the following four possibilities)

Choose the secondary interactions in the polymers I) polyethylene, II) polyamide, III) Polyester, IV) Polyacrylic acid sodium salt: (Choose from the following four possibilities)

condensation polymerization reactions such as polyamide or polyester polymerization are classified as stepwise reaction processes because (Choose from the following four possibilities)

condensation polymerization reactions are classified as stepwise reaction processes because (Choose from the following four possibilities)