All resonance structures for the product of head-to-tail addition shown in Figure 26-11 are to be drawn. Then curved-arrow notation is to be used to show the movement of electrons in the head-to-tail addition of a growing chain of poly(ethyl acrylate) to a molecule of ethyl acrylate. The resonance structures are to be drawn to explain why head-to tail addition occurs instead of head-to-head addition. Concept introduction: Styrene is an unsymmetric vinyl monomer, so we can differentiate between the two carbons of the vinyl group. The less substituted carbon is called the tail, and the more substituted carbon is called the head. As a result, regiochemistry comes into play during polymerization because there are two possible ways the radical can add to the vinyl group of styrene: head-to-tail and head-to-head. The head-to-tail addition is favored in the polymerization of polystyrene for the two reasons shown in Figure 26-11. First, steric repulsion between the two phenyl groups (one at the end of the propagating radical and one in the monomer) makes it less likely that a head-to-head collision will bring the bond-forming carbons within a bond length. Secondly, the radical formed in the head-to-tail addition is more stable. The radical produced from head-to-tail addition is resonance stabilized while the radical produced from head-to-head addition is not.

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Definition Definition Chemical process in which one or more monomers combine to produce a very large chain-like molecule called a polymer. The functional groups present on the monomers and their steric effects are responsible for polymerization through a sequence of reactions that vary in complexity. There exists a stable covalent chemical bond between monomers that sets apart polymerization from other processes.

Chapter 26, Problem 26.7YT

Interpretation Introduction

Interpretation:

All resonance structures for the product of head-to-tail addition shown in Figure 26-11 are to be drawn. Then curved-arrow notation is to be used to show the movement of electrons in the head-to-tail addition of a growing chain of poly(ethyl acrylate) to a molecule of ethyl acrylate. The resonance structures are to be drawn to explain why head-to tail addition occurs instead of head-to-head addition.

Concept introduction:

Styrene is an unsymmetric vinyl monomer, so we can differentiate between the two carbons of the vinyl group. The less substituted carbon is called the tail, and the more substituted carbon is called the head. As a result, regiochemistry comes into play during polymerization because there are two possible ways the radical can add to the vinyl group of styrene: head-to-tail and head-to-head.

The head-to-tail addition is favored in the polymerization of polystyrene for the two reasons shown in Figure 26-11. First, steric repulsion between the two phenyl groups (one at the end of the propagating radical and one in the monomer) makes it less likely that a head-to-head collision will bring the bond-forming carbons within a bond length. Secondly, the radical formed in the head-to-tail addition is more stable. The radical produced from head-to-tail addition is resonance stabilized while the radical produced from head-to-head addition is not.

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Answer 2

Question

Definition Definition Chemical process in which one or more monomers combine to produce a very large chain-like molecule called a polymer. The functional groups present on the monomers and their steric effects are responsible for polymerization through a sequence of reactions that vary in complexity. There exists a stable covalent chemical bond between monomers that sets apart polymerization from other processes.

Chapter 26, Problem 26.7YT

Interpretation Introduction

Interpretation:

All resonance structures for the product of head-to-tail addition shown in Figure 26-11 are to be drawn. Then curved-arrow notation is to be used to show the movement of electrons in the head-to-tail addition of a growing chain of poly(ethyl acrylate) to a molecule of ethyl acrylate. The resonance structures are to be drawn to explain why head-to tail addition occurs instead of head-to-head addition.

Concept introduction:

Styrene is an unsymmetric vinyl monomer, so we can differentiate between the two carbons of the vinyl group. The less substituted carbon is called the tail, and the more substituted carbon is called the head. As a result, regiochemistry comes into play during polymerization because there are two possible ways the radical can add to the vinyl group of styrene: head-to-tail and head-to-head.

The head-to-tail addition is favored in the polymerization of polystyrene for the two reasons shown in Figure 26-11. First, steric repulsion between the two phenyl groups (one at the end of the propagating radical and one in the monomer) makes it less likely that a head-to-head collision will bring the bond-forming carbons within a bond length. Secondly, the radical formed in the head-to-tail addition is more stable. The radical produced from head-to-tail addition is resonance stabilized while the radical produced from head-to-head addition is not.

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Answer 3

Question

Definition Definition Chemical process in which one or more monomers combine to produce a very large chain-like molecule called a polymer. The functional groups present on the monomers and their steric effects are responsible for polymerization through a sequence of reactions that vary in complexity. There exists a stable covalent chemical bond between monomers that sets apart polymerization from other processes.

Chapter 26, Problem 26.7YT

Interpretation Introduction

Interpretation:

All resonance structures for the product of head-to-tail addition shown in Figure 26-11 are to be drawn. Then curved-arrow notation is to be used to show the movement of electrons in the head-to-tail addition of a growing chain of poly(ethyl acrylate) to a molecule of ethyl acrylate. The resonance structures are to be drawn to explain why head-to tail addition occurs instead of head-to-head addition.

Concept introduction:

Styrene is an unsymmetric vinyl monomer, so we can differentiate between the two carbons of the vinyl group. The less substituted carbon is called the tail, and the more substituted carbon is called the head. As a result, regiochemistry comes into play during polymerization because there are two possible ways the radical can add to the vinyl group of styrene: head-to-tail and head-to-head.

The head-to-tail addition is favored in the polymerization of polystyrene for the two reasons shown in Figure 26-11. First, steric repulsion between the two phenyl groups (one at the end of the propagating radical and one in the monomer) makes it less likely that a head-to-head collision will bring the bond-forming carbons within a bond length. Secondly, the radical formed in the head-to-tail addition is more stable. The radical produced from head-to-tail addition is resonance stabilized while the radical produced from head-to-head addition is not.

Expert Solution & Answer

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Answer 4

Question

Definition Definition Chemical process in which one or more monomers combine to produce a very large chain-like molecule called a polymer. The functional groups present on the monomers and their steric effects are responsible for polymerization through a sequence of reactions that vary in complexity. There exists a stable covalent chemical bond between monomers that sets apart polymerization from other processes.

Chapter 26, Problem 26.7YT

Interpretation Introduction