Chemistry 367L/392N

Paul J Flory 1910Paul J Flory 1910--19851985

Macromolecular ChemistryMacromolecular Chemistry

Wallace H. Carothers 1896Wallace H. Carothers 1896--19371937

Chemistry 367L/392N

Nomenclature MethodsNomenclature Methods� Source name (more common use)

– based on monomer name (polystyrene)

� IUPAC, constitutional repeating unit– used in both source and structure

names…messy!

� Abbreviations and acronyms– PMMA [poly(methyl methacrylate)]…also

common

� Trade names– marketing and technological literature

Chemistry 367L/392N

ExamplesExamplesCH CH2

O C CH3

O

CH CH CH2 CH2

CH CH2

C N

CH2

OO

O

CH2

Ph

1. Poly(1-acetoxyethylene) - structure2. Poly(vinyl acetate) - source

1. Poly(but-1-ene-1,4-diyl)2. Polybutadienea

1. Poly(1-cyanoethylene)2. Polyacrylonitrile

1. Poly(methylene)2. Polyethene; polyethylene

1. Poly[(2,5-dioxotetrahydrofuran-3,4-diyl)(1-phenylethylene)]

2. Poly(maleic anhydride-alt-styrene)

Chemistry 367L/392N

Industrial Influence: Trade Names Industrial Influence: Trade Names

� PVC poly (vinylidene chloride) Saran wrap� PVC poly (vinyl chloride) Pipe and records� PET poly (ethylene teraphthalate) Coke bottles, Dacron � Polystyrene Cups and packaging� Delrin Bushings and engineering parts� Lexan Bullet proof glass� Teflon Non stick pans� PVDF speakers and microphones� Kevlar bullet proof vests� Nylon Rope and fiber

Chemistry 367L/392N

Common AbbreviationsCommon AbbreviationsSelected examples

ABS (acrylonitrile butadiene styrene)LLDPE (linear low density polyethylene)PA66 [polyamide (Nylon) 66]PC (polycarbonate)PET [poly(ethylene terephthalate)]PMMA [poly(methyl methacrylate)]PS (polystyrene)PVC [poly(vinyl chloride)]TP (thermoplastic elastomer polyolefin)PVF2 [poly(vinlylidine fluoride)]

(www.plasticsusa.com/tradename.html)

Chemistry 367L/392N

Class NamesClass Names� Polyolefin

� Polyester

� Polyamide

� Polycarbonate

� Polyurethane

Naming Naming ““classesclasses”” of polymersof polymers

Chemistry 367L/392N

Cl Br Cl BrBrCl

Poly(ethylene-alt-carbon monoxide)

Poly(1-oxopropanediyl)

CH2-O -CH-CCl-CH2-O-CH-CHCl-CH2-O-CH-CHCl

CH3 CH3 CH3

Poly(vinyl alcohol)

Poly(1-methyl-1-phenylethylene)

Name Name ‘‘emem or draw or draw ‘‘emem

Chemistry 367L/392N

Wallace Hume Carothers 1896Wallace Hume Carothers 1896--19371937

Carothers, W.H., J. Am. Chem. Soc. 1929, 51, 2548-58

Chemistry 367L/392N

Carothers PaperCarothers Paper

Chemistry 367L/392N

Addition polymerAddition polymer

� Polystyrene

C CH

H

H C

H

C C C

H H

H H H

( )n

Chemistry 367L/392N

Addition PolymerAddition Polymer� Polyvinylchloride

C C

H

H

Cl

H

chloroethene

C C C C

H H H H

H HCl Cl

poly(chloroethene) aka polyvinylchloride (pvc)

Chemistry 367L/392N

Condensation PolymerCondensation Polymer� Dacron

HO C

O

C

O

OHn + HO CH2 CH2 OHn

heat with an acid catalyst

C

O

C

O

O CH2 CH2 O

poly(ethan-1,2-diyl benzene-1,4-dicarboxylate)

n

H2O +

Chemistry 367L/392N

Condensation PolymerCondensation Polymer

N (CH2)6 NH

H

H

HC

O

OH(CH2)4

HO

OC

1,6-diaminohexane hexanedioic acid

N (CH2)6

H

N

H

C

O

(CH2)4 C

O

part of a nylon polymer chain

( )n

Nylon 6,6

H2O +

Chemistry 367L/392N

Chemistry 367L/392N

Carothers DefinitionCarothers Definition

A d d itio nCO2H

HO2CHO

OHO

OO

HO

O

H+

(

(

Condensation

- H2O

N C O

N C O

HOOH

OCNHN O

OO N

H

OAr

+

Condensation?

O

O O

O O

O

Condensation?

Addition?

Problems with Carothers DefinitionProblems with Carothers Definition

Chemistry 367L/392N

Another ProblemAnother Problem

from ωωωω-hydroxycarboxylic acid

O R C

O

O C

O

R

OH R CO2H O R C

O

+ H2O

Polyester from lactone

Chemistry 367L/392N

Paul J FloryPaul J Flory 19101910--19851985

The Nobel Prize in Chemistry 1974

"for his fundamental achievements, both theoretical and experimental, in the physical chemistry of the macromolecules"

Chemistry 367L/392N

Flory Clears Things UpFlory Clears Things UpPolymer Structure is distinct from Polymerization Process.

O

O O

OH

HO

O

OH

HO

AdditionPolymerization

CondensationPolymerization

CondensationPolymer

� Release of small molecules

� Degradation gives different

composition

� New functional groupsCondensation

� Same composition

(monomer = polymer)

� Similar connections

� Ring-opening

� No by-products

Addition

StructureProcess

Chemistry 367L/392N

Basic Types of Polymerization MechanismsBasic Types of Polymerization Mechanisms

Chain-growth

Step-growth

Ring-openingO

OO-

O

RO-O

ORO

H+

CH2CO

HO CH2 OH CH2CO

O CH2 O HH

H2O

DimerTetramerOctamerHexamer

...

Chemistry 367L/392N

Chain growth systemChain growth system

The characteristic of a chain polymer is that The characteristic of a chain polymer is that polymer growth takes place by monomer reacting polymer growth takes place by monomer reacting only with the reactive centersonly with the reactive centers.. Monomer does not Monomer does not react with monomer and the differentreact with monomer and the different--sized species sized species such as such as dimerdimer, , trimertrimer, and , and nn--mermerdo not react with do not react with each other. The polymerization ceases when the each other. The polymerization ceases when the active center is destroyed by termination active center is destroyed by termination reaction(sreaction(s). ).

Chemistry 367L/392N

A condensation takes place between two A condensation takes place between two polyfunctionalpolyfunctionalmolecules to produce one molecules to produce one larger polyfunctional molecule with the larger polyfunctional molecule with the possible elimination of a small molecule such possible elimination of a small molecule such as water. The reaction continues until one of as water. The reaction continues until one of the reagents is used up. the reagents is used up.

Step Growth systemStep Growth system

Chemistry 367L/392N

The chain growth vs. step growthThe chain growth vs. step growth

Step Chain