Which polymer would be more apt to contain abnormal

Draw short segments of the polymers obtained from the following monomers. In each case, indicate whether the polymerization is a chain-growth or a step-growth polymerization.

Draw the repeating unit of the step-growth polymer that will be formed from each of the following pairs of monomers:

Draw the structure of the monomer or monomers used to synthesize the following polymers, and indicate whether each is a chain-growth polymer or a step-growth polymer.

Explain why the coni guration of a polymer of isobutylene is neither isotactic, syndiotactic, nor atactic.

Draw short segments of the polymers obtained from the following compounds under the given reaction conditions:

Quiana is a synthetic fabric that feels very much like silk. a. Is Quiana a nylon or a polyester? b. What monomers are used to synthesize it?

Explain why a random copolymer is obtained when 3,3-dimethyl-1-butene undergoes cationic polymerization.

A chemist carried out two polymerization reactions. One l ask contained a monomer that polymerizes by a chain-growth mechanism, and the other l ask contained a monomer that polymerizes by a step- growth mechanism. When the reactions were terminated early in the process and the contents of the l asks analyzed, it was found that one l ask contained a high-molecular-weight polymer and very little material of intermediate molecular weight. The other contained mainly material of intermediate molecular weight and very little high-molecular-weight material. Which l ask contained which product? Explain.

Poly(vinyl alcohol) is a polymer used to make i bers and adhesives. It is synthesized by hydrolysis or alcoholysis of the polymer obtained from polymerization of vinyl acetate as shown here. CH2 CH CH2 CH CH2 CH OCCH3 O OCCH3 O OCCH3 CH2 CH CH2 CH CH2 CH OH OH OH O H2O poly(vinyl alcohol) poly(vinyl acetate) a. Why is poly(vinyl alcohol) not prepared by polymerizing vinyl alcohol? b. Is poly(vinyl acetate) a polyester?

Five different repeating units are found in the polymer obtained by cationic polymerization of 4-methyl- 1-pentene. Identify these repeating units.

If a peroxide is added to styrene, the polymer known as polystyrene is formed. If a small amount of 1,4-divinylbenzene is added to the reaction mixture, a stronger and more rigid polymer is formed. Draw a short section of this more rigid polymer.

A particularly strong and rigid polyester used for electronic parts is marketed under the trade name Glyptal. It is a polymer of terephthalic acid and glycerol. Draw a segment of the polymer and explain why it is so strong.

The following two compounds form a 1 : 1 alternating copolymer. No initiator is needed for the polymerization. Propose a mechanism for formation of the copolymer.

Which monomer would give a greater yield of polymer, 5-hydroxypentanoic acid or 6-hydroxyhexanoic acid? Explain your choice

When rubber balls and other objects made of natural rubber are exposed to air for long periods, they turn brittle and crack. Explain why this happens more slowly to objects made of polyethylene.

When acrolein undergoes anionic polymerization, a polymer with two types of repeating units is obtained. Draw the structures of the repeating units.

Why do vinyl raincoats become brittle as they get old, even if they are not exposed to air or to any pollutants?

The polymer shown here is synthesized by hydroxide ion-promoted hydrolysis of a copolymer of para -nitrophenyl methacrylate and acrylate. a. Propose a mechanism for the formation of the copolymer. b. Explain why hydrolysis of the copolymer to form the polymer occurs much more rapidly than hydrolysis of para-nitrophenyl acetate.

An alternating copolymer of styrene and vinyl acetate can be turned into a graft copolymer by hydrolyzing it and then adding ethylene oxide. Draw the structure of the graft copolymer.

How could head-to-head poly(vinyl bromide) be synthesized?

Delrin (polyoxymethylene) is a tough self-lubricating polymer used in gear wheels. It is made by polymerizing formaldehyde in the presence of an acid catalyst. a. Propose a mechanism for formation of a segment of the polymer. b. Is Delrin a chain-growth polymer or a step-growth polymer?

What monomer would you use to form each of the following polymers?

Problem 2P Which polymer would be more apt to contain abnormal head-to-head linkages: poly(vinyl chloride) or polystyrene?

Draw a segment of polystyrene that contains two head-to-head, two tail-to-tail, and two head-to-tail linkages.

Problem 4P Show the mechanism for the formation of a segment of poly(vinyl chloride) containing three units of vinyl chloride and initiated by HO-.

Problem 5P Polyethylene can be used for the production of bcach chairs as well as beach balls. Which of these items is made from more highly branched polyethylene?

Problem 6P Draw a short segment of branched polystyrene.

List the following groups of monomers in order from most able to least able to undergo cationic polymerization:

List the following groups of monomers in order from most able to least able to undergo anionic polymerization:

Problem 9P Why does methyl methacrylate not undergo cationic polymerization?

Problem 10P Explain why, when propylene oxide undergoes anionic polymerization, nucleophilic attack occurs at the less substituted carbon of the epoxide, but when it undergoes cationic polymerization,nucleophilic attack occurs at the more substituted carbon.

Problem 11P Describe the polymerization of 2,2-dimethyloxirane by a. an anionic mechanism. b. a cationic mechanism.

Which monomer and which type of initiator would you use to synthesize each of the following polymers?

Draw a short segment of the polymer formed from cationic polymerization of \(3,3\)- dimethyl oxacyclobutane. Equation Transcription: Text Transcription: 3,3

Problem 14P Draw a short segment of gutta-percha.

Problem 15P Draw a segment of the polymer that would be formed from 1,2-polymerization of 1,3-butadiene.

Problem 16P a. Draw a short segment of nylon 4. b. Draw a short segment of nylon 44.

Problem 17P Write an equation that explains what will happen if a scientist working in the laboratory spills sulfuric acid on her nylon 66 hose.

Propose a mechanism for the base-catalyzed polymerization of \(\varepsilon\)-caprolactam. Equation Transcription: Text Transcription: epsilon

Problem 19P What happens to polyester slacks if aqueous NaOH is spilled on them?

a. Propose a mechanism for the formation of the prepolymer formed by bisphenol A and epichlorohydrin. b. Propose a mechanism for the reaction of the prepolymer with the hardener.

Explain why, when a small amount of glycerol is added to the reaction mixture of toluene- \(2,6\)-diisocyanate and ethylene glycol during the synthesis of polyurethane foam, a much stiffer foam is obtained. Equation Transcription: Text Transcription: 2,6

Problem 22P Propose a mechanism for the formation of Melmac.

Problem 23P Bakelite, a durable plastic used for the casing of early radios and TVs, was the first of the thermosetting polymers. It is a highly cross-linked polymer formed from the acid-catalyzed polymerization of phenol and formaldehyde. Because it is much darker than Melmac, Bakelite’s range of colors is limited. Propose a structure for Bakelite.

Problem 24P a. Draw the structure of a short segment of PHB. b. Draw the structure of a short segment of PHBV with alternating monomers.

Draw short segments of the polymers obtained from the following monomers. In each case, indicate whether the polymerization is a chain-growth or a step-growth polymerization.

Draw the repeating unit of the step-growth polymer that will be formed from each of the following pairs of monomers:

Draw the structure of the monomer or monomers used to synthesize the following polymers, and indicate whether each is a chain growth polymer or a step-growth polymer.

Problem 28P Explain why the confi guration of a polymer of isobutylene is neither isotactic, syndiotactic, nor atactic.

Draw short segments of the polymers obtained from the following compounds under the given reaction conditions:

Quiana is a synthetic fabric that feels very much like silk. a. Is Quiana a nylon or a polyester? b. What monomers are used to synthesize it?

Explain why a random copolymer is obtained when \(3,3\)-dimethyl-\(1\)-butene undergoes cationic polymerization. Equation Transcription: Text Transcription: 3,3 1

Problem 32P A chemist carried out two polymerization reactions. One flask contained a monomer that polymerizes by a chain-growth mechanism, and the other flask contained a monomer that polymerizes by a step-growth mechanism. When the reactions were terminated early in the process and the contents of the fl asks analyzed, it was found that one flask contained a high-molecular-weight polymer and very little material of intermediate molecular weight. The other contained mainly material of intermediate molecular weight and very little high-molecular-weight material. Which flask contained which product? Explain.

Problem 34P Five different repeating units are found in the polymer obtained by cationic polymerization of 4-methyl-1-pentene. Identify these repeating units.

Poly(vinyl alcohol) is a polymer used to make i bers and adhesives. It is synthesized by hydrolysis or alcoholysis of the polymer obtained from polymerization of vinyl acetate as shown here.

If a peroxide is added to styrene, the polymer known as polystyrene is formed. If a small amount of \(1,4\)-divinylbenzene is added to the reaction mixture, a stronger and more rigid polymer is formed. Draw a short section of this more rigid polymer. Equation Transcription: Text Transcription: 1,4

Problem 36P A particularly strong and rigid polyester used for electronic parts is marketed under the trade name Glyptal. It is a polymer of terephthalic acid and glycerol. Draw a segment of the polymer and explain why it is so strong.

The following two compounds form a \(1: 1\) alternating copolymer. No initiator is needed for the polymerization. Propose a mechanism for formation of the copolymer. Equation Transcription: Text Transcription: 1 : 1

Problem 38P Which monomer would give a greater yield of polymer, 5-hydroxypentanoic acid or 6-hydroxyhexanoic acid? Explain your choice.

Problem 39P When rubber balls and other objects made of natural rubber are exposed to air for long periods, they turn brittle and crack. Explain why this happens more slowly to objects made of polyethylene.

When acrolein undergoes anionic polymerization, a polymer with two types of repeating units is obtained. Draw the structures of the repeating units.

Problem 41P Why do vinyl raincoats become brittle as they get old, even if they are not exposed to air or to any pollutants?

The polymer shown here is synthesized by hydroxide ion-promoted hydrolysis of a copolymer of para -nitrophenyl methacrylate and acrylate. a. Propose a mechanism for the formation of the copolymer. b. Explain why hydrolysis of the copolymer to form the polymer occurs much more rapidly than hydrolysis of para -nitrophenyl acetate.

Problem 43P An alternating copolymer of styrene and vinyl acetate can be turned into a graft copolymer by hydrolyzing it and then adding ethylene oxide. Draw the structure of the graft copolymer.

How could head-to-head poly(vinyl bromide) be synthesized?

Problem 45P Delrin (polyoxymethylene) is a tough self-lubricating polymer used in gear wheels. It is made by polymerizing formaldehyde in the presence of an acid catalyst. a. Propose a mechanism for formation of a segment of the polymer. b. Is Delrin a chain-growth polymer or a step-growth polymer?