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General Approaches to Polymer Synthesis 1. Addition Chain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of Cyclic Olefins 2. Condensation Step Growth Polymerization of A-B or AA/BB Monomers 3. Modification of Preformed Polymers Polysaccharides Peptides and Proteins Synthetic Precursors

General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

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Page 1: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

General Approaches to Polymer Synthesis

• 1. Addition Chain GrowthPolymerization of Vinyl Monomers

Ring Opening Polymerization Heterocylics Metathesis of Cyclic Olefins

2. Condensation Step Growth  Polymerization of A-B or AA/BB Monomers3. Modification of Preformed Polymers

Polysaccharides

Peptides and Proteins   Synthetic Precursors

Page 2: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Major Developments in the 1950-60's

Living Polymerization (Anionic)• Mw/Mn 1• Blocks, telechelics and stars available

(Controlled molecular architecture)• Statistical Stereochemical Control• Statistical Compositions and Sequences• Severe functional group restrictions

Page 3: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Ziegler-Natta (Metal-Coordinated) Polymerization

• Stereochemical Control

• Polydisperse products

• Statistical Compositions and Sequences

• Limited set of useful monomers, i.e. olefins

• SINGLE SITE CATALYSTS

Page 4: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Additional Developments in the 1980's

• "Immortal" Polymerization (Cationic)– Mw/Mn 1.05– Blocks, telechelics, stars– (Controlled molecular architecture)– Statistical Compositions and Sequences– Severe functional group restrictions

Page 5: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Free Radical Initiated Polymerization

• Controlled Free Radical Polymerization

• Broad range of monomers available

• Accurate control of molecular weight

• Mw/Mn 1.05 --Almost monodisperse

• Blocks, telechelics, stars

• (Controlled molecular architecture)

• Statistical Compositions and Sequences

Page 6: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Current Strategies in Polymer Synthesis 

• Objectives: Precise Macromolecular Design

• 1 . Control of: Molecular Weight– Molecular Weight Distribution– Composition– Sequence of repeat units– Stereochemistry

• 2.  Versatility

Page 7: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Genetic Approaches via Modified

Microorganisms • Monodisperse in MW

• Monodisperse in Composition

• Sequentially Uniform

• Stereochemically Pure

• Diverse set of functional groups possible through synthesis of novel amino acids

Page 8: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Step-Growth or Condensation Polymerizations

Molecular Weight predicted by Carothers Equation:A-A + B-B -[A-B-]x + x C [A-A] = [B-B] = No# of functional groups remaining at anytime = N

Extent of reaction = pNo - N

p = _____ or N = No (1 - p) No

Degree of Polymerization, D.P. = No / N = 1 / (1 - p)

Page 9: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Problems in Achieving High D. P.

1. Non-equivalence of functional groups

a. Monomer impurities1. Inert impurities (adjust stoichiometry)2. Monofunctional units terminate chain

b. Loss of end groups by degradation

c. Loss of end groups by side reactions with media

d. Physical losses e. Non-equivalent reactivity

f. Cyclization

. Unfavorable Equilibrium Constant

Page 10: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Impact of percent reaction, p, on DP

if p = DP =

0.5 2

0.7 3.3

0.9 10

0.95 20

0.99 100

0.999 1000

Degree of Polymerization, D.P. = No / N = 1 / (1 - p)Assuming perfect stoichiometry

DPmax= (1 + r) / (1 - r) where r molar ratio of reactants

if r = [Diacid] / [diol] = 0.99, then DPmax= 199

Page 11: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Cyclization

1. Thermodynamic stability

Rings of: 3,4,8 < 11 < 7, 12 << 5 << 6

2. Kinetic Control

Propagation more rapid than cyclization

Reduce probability of collision for rings 12

Non-reversible propagation process

Page 12: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Equilibrium in Polyesterification

OH

O+

OH

O

O+

H2O

Keq =[-COO-] [H2O]

[COOH] [OH]=

(p [M]o)2

([M]o - p([M]o)2

Keq =p2

(1-p)2

Reaction in closed system

p = fraction esterified

p =K1/2

1-K1/2

DP = 1/(1-p) DP = 1 + K1/2

Page 13: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Equilibrium in Polyesterification

Effect of Keq on extent of reaction and DP

Keq p Xn

0.01 0.1 1.11

1 0.5 2

16 0.8 5

81 0.9 10

361 0.95 20

9800 0.99 100

39,600 0.995 200

DP = 1 + K1/2

transesterification

esterification

amide formation

Page 14: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Driving reaction to completion in open,

driven system Keq DP [H2O]

1 2 2.5

20 0.0132

50 0.00204

100 0.000505

200 0.000126

16 5 4.0

20 0.211

50 0.0327

100 0.0081

200 0.00201

Page 15: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Types of Condensation Reactions

1. Polyesters

R OHHO R'OHHO

O O+

- n H2OR O R' O

O O

* *n

R OHHO R'OCH3H3CO

O O+

- n CH3OHR O R' O

O

* *n

O

OOO

R OHHO +

OOORHO OH

OOOR O **

-n H2O

n

O

O

(CH2)5HO C

O

OH (CH2)5 C

O

O

H2O

trace

-n H2O

Page 16: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Preparation of Aromatic Polyesters

CC

O

O

O

O CH3H3C

HO-CH2CH2-OHxs

CC

O

O

O

O HH

Dimethyl Terephthalate (DMT)

Terephthalic Acid

CC

O

O

O

O

CH2CH2

CH2OH CH2OH

CH3OH+

CC

O

O

O

O

CH2CH2

CH2OH CH2OH

1 mm Hg 280 C

SbO3 or Ti(OR)4

CC

O

O

O

O

CH2

CH2O

+ HOCH2CH2OH

Stoichiometry and DP controlled by extent of glycol removed.

Page 17: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Types of Condensation Reactions

R NH2H2N R'OHHO

O O+

- n H2OR

HN R' N

H

O O

* *n

R NH2H2N R'ClCl

O O+

- n HClR

HN R' N

H

O O

* *n

2. Polyamides

NH

O

(CH2)5H2N C

O

OH (CH2)5 C

O

NH

H2O

trace

-n H2O

Page 18: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Polyamides via Condensation -- Nylon 66

C-(CH2)4-C

OO

OOH

H

CH2-(CH2)4

-CH2 NH2NH2

+

slight excess

C-(CH2)4-C

OO

O- O-

(CH2)4

CH2 CH2

NH3+ NH3

+

Nylon Salt

60% Slurry

200 C, 15 Atm. 1 hr

NH3+(CH2)6

-NH-C-(CH2)4-C-NH-(CH2)6

-NH-C-(CH2)4-C

O

OO

OO-

8-10

270-300 C, 1hr

- H2O

NH-(CH2)6-NH-C-(CH2)4

-C

O

O

Nylon 6 6

mp. 265C, Tg 50C, MW 12-15,000Unoriented elongation 780%

Page 19: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Types of Condensation Polymers

R O C R' C On

O

Rn

O

R' C On

O

C

O

O

O

O n

Polyesters

Polycarbonates

Polyanhydrides

O O

Rn

Polyacetals

Page 20: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Lexan Polycarbonate

CH3 CH3

OO --

Na+ Na++ Cl-C-Cl

O

Aq NaOH

CHCl2

CH3 CH3

OC

O

O

+ NaCl

xLexan

Interfacial Process

Tm = 270C,

Tg = 145-150C10-40 % Crystalline, Brittle Temp. - 10C

Ester Interchange

OC

O

O

+

CH3 CH3

OOH

H

1) 200 C/20mm

2) 300 C. <1mm

Lexan +

OH

No Solvent, Pure Polymer with MW > 30,000 Formed

Page 21: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Types of Condensation Polymers

RHN R' N

HO

O

C

O

O

CH3

CH3

O

R

O O

SO O

Ar

polyurethanes polyphenylene oxide

polyarylenes

polyarylene ether sulfones

Page 22: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Low Temperature Condensation Polymerization

• Interfacial or Solution in Polar Aprotic Solvents

Parameter Low Temp High Temp

Intermediates

Purity

Stoichiometry

Heat Stability

Structure

Cost

Moderate

Not Essential

Not Essential

Highly Reactive

High

High

Essential

Essential

Thermally stable

Moderate

Page 23: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Interfacial or Solution Polymerization in Polar Aprotic Solvents (Con’t)

Conditions Low Temp High Temp

Time

Temperature

Pressure

Yield

By-products

Solvents

Minutes to hours

0 – 150 CAtmospheric

Low to moderate

Salts

Required

Hours to days

>250 CHigh to vacuum

Quantitative

Volatiles

None

Page 24: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Applications of Low Temperature Condensations

• Prep. of Infusible Thermally Stable Polymers

• Prep. of Thermally Unstable Polymers

Prep. of Polymers Containing Functional Groups with Differing Reactivity

Formation of Block or Ordered Polymers(No equilibration of polymer in melt allowed)

Direct Production of Polymer Solutions for Coatings, Spinning into Fibers, Solvent Blending to form Composites

Page 25: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Types of Condensation Polymers

RHN C R' C N

H

O O

NN

O

O

O

O

N

OO

N

Ar

N

SS

N

Ar

polyamidespolyimides

polybenzoxazolespolybenzthiazoles

Page 26: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Aromatic Polyamides “Aramids”

NH2

NH2

+

C-Cl

C-Cl

O

O

SO O

DMF, LiCl

C-NH

C-NH

NH-C

C-NH

NH-CO

O

OO

O

Can be Dry Spun to FiberAs Spun: Elongation, 23-34%,Tenacity, 4.6-5.3 g/Denier

70% Strength Retained in Ionizing Radiation

Nomex M.p. > 350 C

Unique solvent combination

M-isomers favor formation of soluble polymers

Page 27: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Polyimides for Electronic Applications

C-O

O-C

O

O

C-Cl

Cl-C

O

O

Cl-C-C-Cl

O

O syn and anti isomers

C-O

O-C

HO-C

C-OH

O

O O

O2 (CH

3)2CHOH

PMDA

ONH2

NH2

ODADMAC

C-O

O-C

O

O

C-NH

NH-C

O

O

O

N ON

O

O

O

O

heat or

amine catalyst

soluble

insoluble

O

O

O

O

O O

Kevlar

Fabricate in soluble form

Post treat to final form

Page 28: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

POLYETHERSULFONES

160 C

OO

OS

CH3O

2) CH3Cl

DMSO/Toluene

Cl S

Cl

O

O+

K+-O

O- K+

HO

OH

K+-O

O- K+

K2CO

3

Bis-Phenol-A

Molecular Weight = 65,000 - 250,000Amorphous Material, Tg 200C, Films pressed at 280C

Use Temperature -100 to + 175CStable in air to 500C, Self Extinguishing

Bis-nucleophile

Polymerize by SnAr2

Monofunctional terminator to stabilize polymer

Page 29: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Polyphenylene Oxide (PPO)

R1

R2

OH + n/2 O2

R1

R2

O O

R2

R1

+ n H2O

cat

cat = N

NCH3

CH3N

CH3

CH3

3 : 1

or

10:1

Cu+

Amine Complex

Noryl is a blend with polystyrene

Oxidative Coupling Process

Mn 30,000 to 120,000Amorphous , Tg 210C Crystalline, Tm 270CBrittle point -170CThermally Stable to 370C

Page 30: General Approaches to Polymer Synthesis 1.AdditionChain Growth Polymerization of Vinyl Monomers Ring Opening Polymerization Heterocylics Metathesis of

Noryl is Unique Blend• Single Phase, Tg dependent upon composition• Maximum tensile strength at 80 wt% PPO• Other properties; volume fraction weighted average• Blend compatible with rubber modified polystyrene (high impact

resistance)

• Applications of Noryl Engineering Thermoplastics• Useful properties• High impact resistance• Flame retardant• High chemical stability• Low moisture absorbance (0.07%0• Use in appliance housings• Automobile dashboards• Radomes, fuse boxes, wiring splice devises