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Commercial Polymers AK_Spiess Basis Seminar Chulsoon Moon 16.04.2008
Commercial Polymers
AK_Spiess Basis Seminar
Chulsoon Moon16.04.2008
Outline• Classification of polymers
Natural vs. syntheticAddition vs. Condensation Thermoplastic vs. Thermosetting
• Commercial polymersthe most commonly used polymers in ordinary life (poymerization, property, application)
• NMR in polymer analysisComposition (copolymers, polymer/additives)Mircro-structure (branching, tacticity, enchainment, sequence distribution…)Molecular weight (End-group analysis)
Classification of Polymers
• Natural polymers: plants, animal, and people..(starch, cellulose, proteins, silk, and natural rubber…)
• Synthetic polymers: plastics, commercial polymers..(styrene-butadiene rubber, nylon, PE, PP, PVC, ABS, SAN, PMMA..)
OH CH2
CH2
OH OH CO
CO
OH O CCH2CH2 CO
OO
CH2CH2+
Polymerization mechanisms
• Condensation polymers (step growth polymers)
• Addition polymers (chain growth polymers)
(Polyester, polycarbonate, polyamide, polyurethane..)
(Polymers from alkenes or functionalized alkenes..)
Z*: an initiating species (a radical, cation, anion)
CR
CH
H
HCH
C*H H
Rz
CH2=CHRCH
Hz C
R
HCH
HC*
R
H
C CH R
H Hn
Z* repeating
PET
Thermal properties
• Thermoplastic polymers: soften reversibly when heated
• Thermosetting polymers: harden permanently when heated
• Cross-linking hinder bending and rotations (harder, more brittle)
•Epoxy resins, phenol resins..
• Molded and remolded easily
•Addition polymers (ABS, PP, PVC, ABS, PET…)
PET(Poly ethylene terephthalate)
• trans-esterification of ethylene gylcol + terephthalic acid condensation & thermoplastic polymer
• Good transparency, strength, and gas barrier propertywidely used for soft drink bottle
• Recycling is more practical
+
• The simplest and the most popular polymer in the world• Grocery bag, shampoo bottles, electrical insulation,
children’s toys• Depending on polymerization processes:
LDPE(Low-Density PE :more branching :soft) HDPE(High-Density PE :high crystallinity :rigid)
PE(Poly ethylene)
**
n
C CH
H H
H
ethenePolyethylene(HDPE, LDPE)
CH3
CH2• CH3CH•
Six-membered transition stateC4 branch
C2H4
C2,C6 branch
Backbiting Mechanism
CH
CH2•
Multi-intramolecular transfer
PE(Microstructure_branching)
35 30 25 20 15 10 5 ppm
6215
10
12
10
00734
Branch contents
C1 C2 C4 C5 C 6
4.3 5.1 10.1 2.9 6.3
13.36.221.410.89.1
octeneheptenehexenebutenepropene
Monomer contensts (mole ratio)
C2
C4C5C6
C1
C5C6C4
Ethylene main chain
C6 C1C5
* Ethylene: 1000 mole
C1
PE(Microstructure_branching)
13C-1D in TCE-d2at 100℃
1.01.52.02.53.03.5 ppm
0.
86
90
.8
810
.8
921.
16
41
.1
80
1.
20
11
.24
81
.25
21
.2
85
1.
321
1.
351
1.3
53
1.
37
01
.3
85
1.
443
1.4
54
1.
46
4
1.
91
1
2.3
74
2.4
56
2.
48
42
.48
72
.49
02.
49
32
.4
96
2.
525
2.5
53
2.5
85
2.
60
22
.6
432
.74
8
3.
41
53
.4
263
.43
7
3.
4
67
.7
1.
9
2.
0
OHCH3
n
1
2
3
1
2
3
DMSOH2O
1H-1D NMRAverage Chain number~17(mw~536)
PE main chain
PE(End-group analysis: PE_OH)
PP (Poly Propylene)
• Crystallinity: between LDPE and HDPE • Automotive industry, yogurt container, textiles, stationery
• Structure and property: tacticity
C CH
H
H
CH3
**
n
CH3propene Polypropylene
(PP)
Tacticity
• Is stereochemistry in polymers • Is generally applies to addition polymers with one-hydrogen
substituent• Has to do with which side of the chain the R group is placed.
• Has many things with structure and physical properties(rigidity, crystallinity, solubility, melting point..)
• Can be measured by 1H and 13C-NMR
isotactic syndiotactic atactic
**
n α
β
Methyl
28.228.428.628.829.029.229.4 ppm
28.7
28.9
29.0
mm
mr
rr
β-CH213C-1D in TCE-d2at 100℃
Tacticity(PP)
Isotactic (mm)
syndiotactic(rr)
heterotactic (mr)
CH3 CH3 CH3
CH3
CH3
CH3
CH3 CH3
CH3
PS (Poly Styrene)
• Expanded PS, Extruded PS (Styrofoam) thermal insulation, molded objects as tableware (forks, knives, and spoons)
• Not easily recyclable (takes so long time to decompose)• Co-polymer (SAN, SBR, ABS..)
CHCH2
* n
Polystyrene(PS)
styrene
**n
amorphouscrystals
PS_Tacticity
190 180 170 160 150 140 130 120 110 100 90 80 70 60 50 40 30 20 ppm
41.1
44.4
73.8
74.0
74.2
113.
8
125.
612
6.3
127.
712
7.8
127.
912
8.5
137.
213
8.0
145.
4
145146 ppm
9010
13C-1D in TCE-d2 at 100℃
CHCH2
Iso-
atactic
Syn-
Tacticity_sPS
H
H
H
H
H
Ph
Ph
Ph
Ph
Ph H
Ph
H H H
Ph
H
Ph
H
Ph
H
Ph Ph Ph
H H
Ph
H
H
H
Ph H
Ph Ph
Ph Ph
Syn-
Iso-
atactic
9.5 9.0 8.5 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 ppm
1.25
1.28
1.42
1.90
1.92
2.03
2.07
4.95
4.97
4.98
4.98
5.37
5.40
5.41
6.58
7.04
7.08
14497053
7
500
1H-1D in CDCl3
Ratio of Styrene :1,2-BD(Vinyl):1,4-BD
by 1H-NMR
1,4-BD(-CH=)
Vinyl(=CH2)Vinyl
(-CH=)
Styrene
2 22 32 42 52 62 72 82 93 03 13 23 33 43 53 63 73 83 94 04 14 24 34 44 54 64 74 84 9 p p m
24.9
27.4
27.5
30.1
30.2
32.6
32.7
32.7
33.9
34.1
38.1
43.4
43.5
43.6
74100
Ratio of Cis,Trans Bd by 13C-NMR trans cis
-CH2-
Composition(SBR)
13C-1D in CDCl3
PVC (Poly Vinyl Chloride)
• 2/3 : manufacture of pipe, construction• Cheap, durable, easy to assemble• Rigid and somewhat brittle• Phthalate plasticizer (uPVC:unplasticizer PVC)• Monomer :Carcinogenic nature, Dioxin(as a by-product)
C CH
H
H
Cl*
*n
ClVinyl chloride Polyvinyl chloride
(PVC)
Composition (PVC/DOP)
PVC : DOP = (30.12-4) : 4/4 ≒ 26 : 1 (mole ratio)
9.5 9.0 8.5 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 ppm
87.3
9
30.1
2
4.00
1H-1D in TCE-d2 at 100℃
DOP(Aromatics)
PVC(-CHCl-)
DOP(-OCH2-)
solvent
O
O
O
O
Et
Et
**
Cl
n
Di-n-octyl phthalate(DOP)
PVC
Polymer additives
Additives: Many plastics are virtually useless alone…
Fillers - to enhance properties such as wear/strength/toughness/durability of plastics.Talc and clay may be used to bulk out the plastic reducing costs Plasticizers - to make the plastic less hard or brittle
Stabilisers: to prevent degradation due to moisture or UV lightLubricants: to make the polymer easier to form and self lubricating in use (sulphides and waxes) Flame retardants: to prevent combustion in materials such as domestic foamsBlowing agents: to permit foams to be blown Anti-static agents: to prevent the build up of electrical charge.
