Phantom Plastics™

Dr. Chris DeArmitt FRSC

Phantom Plastics™

A combination of technical expertise and business savvy

n  Over 15 years of experience in innovation and industry: Cookson, Institute for Surface Chemistry (YKI), Electrolux, BASF, Hybrid Plastics & Phantom Plastics

n  Recognized expert in plastics, filled plastics, fillers, dispersants, coupling agents, formulation, stabilization and more

n  Serial innovator: many inventions, 13 patents & 3 Innocentive cash awards

n  Papers, articles, book chapters, presentations & workshops

n  Fellow of the Royal Society of Chemistry & Chartered Chemist

n  Winner of Frost & Sullivan award 2009 and R&D 100 Award 2009

n  Voted top plastics expert world-wide out of over 10 000 peers

n  President of Phantom Plastics providing consultancy and training services to the plastics industry

Your presenter

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Phantom Plastics™

Many faceted approach to deliver solutions

3

Phantom Plastics™ capabilities

Analysis

Problem Solving

Breakthrough Innovation

Global Networking

Marketing

Phantom Plastics™

n  Introduction to fillers and polymers

n  Common fillers and their characteristic properties

n  Common polymers and how structure affects their properties

n  How fillers affect polymer processing and properties of polymers

n  Cheat sheet summarizing how all these factors influence the properties of the composite

n  Misconceptions about filled plastics

n  Further reading, consultants, web resources

A foundation for working with polymers and composites

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Outline

Phantom Plastics™

n Change electrical properties

n Modify specific gravity n  Improve abrasion

resistance n  Improve impact strength n  Improve thermal

conductivity n  Improve moisture

resistance n  Increase adhesion n Appearance, opacity, gloss

n Raise heat resistance n  Increase stiffness n  Increase strength n Reduce shrinkage n  Improve dimensional stability n Reduce flammability n Modify flow n  Increase lubricity n Decrease permeability n  Increase degradability n  Improve processability n Reduce creep

Innumerable different reasons to use fillers Reasons to use fillers

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Phantom Plastics™

Polymer behavior depends on testing speed and temperature St

ress

or F

orce

(MPa

)

Strain or elongation (%)

Increasing temperature or Lower testing speed

Brittle failure

Ductile failure

Break or ultimate

Yield

Energy to break

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Basic polymer mechanical properties

Phantom Plastics™

The notch provides crack initiation and helps consistency

Notched Izod Notched Charpy

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Impact test methodology

Phantom Plastics™

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25Filler Volume (%)

Mod

ulus

(GPa

)

Glass FibreMineral FibreMicaTalcCaCO3Wood FibreNanoclayWollastonite

High aspect ratio is best

8

Fillers improve modulus

Phantom Plastics™

0

10

20

30

40

50

60

70

80

90

0 5 10 15 20 25Filler Volume (%)

Yiel

d St

ress

(MPa

)

Glass FibreMineral FibreMicaTalcCaCO3Wood FibreNanoclayWollastonite

High aspect ratio is best

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Anisotropic fillers can improve yield strength

Phantom Plastics™

Courtesy of Imerys

0 50 100 150 Aspect ratio

Falli

ng W

eigh

t Im

pact

Res

ista

nce

(J)

Talc

Kaolin

Calcium Carbonate

Mica

0

2

4

6

8

10

12

14

Anisotropic fillers worse for impact resistance

Filler in PP copolymer

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Aspect ratio & impact resistance

Phantom Plastics™

Fillers very effective but only in semi-crystalline polymers Influence of glass fibre on HDT/B

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50°C

150°C

200°C

250°C

100°C

Pol

ysty

rene

AB

S

Nor

yl (P

PO

)

Pol

ycar

bona

te

PO

M/A

ceta

l

Pol

ysul

fone

PB

T

Pol

yeth

ersu

lfone

PE

T

Nyl

on 6

,6

PP

S

Unf

illed

+ G

lass

fibr

e

300°C

Phantom Plastics™

Property Isotropic Platy Fibres Modulus ↑ ↑↑ ↑↑↑ Yield Strength ― ↑ ↑↑ HDT in amorphous polymer

― ― ―

HDT in semi x-line polymer

↑ ↑↑ ↑↑↑

Impact resistance ↑ or ↓ ↓ ↓ Elongation to break ↓ ↓↓ ↓↓↓ Permeability ↓ ↓↓ ↓

How to modify the properties of composites

•  Adding dispersant improves impact resistance, elongation, gloss & flow but modulus & yield strength unchanged •  Adding coupling agent will improve yield strength but not modulus, flow may worsen •  Adding impact modifier particles will improve impact resistance but will lower modulus, yield strength and flow •  Isotropic fillers work in all three directions equally •  Platy fillers are very good in two directions and fair in the other •  Fibers are very good in one direction and fair in the other two

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Cheat sheet

Phantom Plastics™

n MFI is a good indicator flow n Coupling agents always couple n Coupling increases modulus n Anisotropic fillers are better n Properties depend on weight % filler n Filler reduce the specific heat capacity of polymers n Nano-composites are new n  Impact strength is a valid term n  Impact resistance is an intrinsic property n Notched impact resistance is most meaningful n Fillers function is just to reduce cost

Some common misconceptions Fallacies

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Phantom Plastics™

Dispersants improve impact resistance: coupling agents for strength

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Surface treatment types

Dispersant Coupling Agent

A --- B A --- B --- C

Anchor --- Buffer Anchor --- Buffer --- Couplant

Phantom Plastics™

Succinic anhydride is a very effective anchor group Anchor group filler specificity

Filler Type Best Dispersant 2nd Best 3rd Best

Calcium Carbonate Succinic anhydride Carboxylic acid Primary amine

Dolomite Sulfonic acid Carboxylic acid Succinic anhydride

Magnesium Hydroxide Succinic anhydride Trichlorosilane Carboxylic acid

Mica Primary amine Trichlorosilane Sulfonic acid

Talc Trichlorosilane --- ---

Silica Trichlorosilane Sulfonic acid Succinic anhydride

Wollastonite Primary amine Succinic anhydride Carboxylic acid

Titanium dioxide Succinic anhydride Carboxylic acid Trichlorosilane

Phantom Plastics™

Courtesy of Imerys

0 10 20 30 Filler volume %

Flex

ural

mod

ulus

(MPa

) Polycarb S – surface treated

Polycarb - untreated

0

1000

2000

3000

4000

5000

40

Coupling and modulus – bonding does not affect modulus

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Coupling agents and modulus

Phantom Plastics™

B. Pukánsky in Polypropylene Stucture, blends & composites vol 3

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Filler volume %

Tens

ile y

ield

str

engt

h (M

Pa)

Stearic acid treated (poorer adhesion)

10

20

20 30 40

30

40

50 0

Untreated (poor adhesion)

Maleated PP (good adhesion)

Coupling and yield strength – coupling agents raise yield strength

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Nanopolymers

Phantom Plastics™

Fibres and flakes align to give high tensile strength and modulus

Direction of flow

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Effect of flow

Phantom Plastics™

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25Filler Volume (%)

Mod

ulus

(GPa

)

Glass FibreMineral FibreMicaTalcCaCO3Wood FibreNanoclayWollastonite

High aspect ratio is best

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Fillers improve modulus

Phantom Plastics™

0

10

20

30

40

50

60

70

80

90

0 5 10 15 20 25Filler Volume (%)

Yiel

d St

ress

(MPa

)

Glass FibreMineral FibreMicaTalcCaCO3Wood FibreNanoclayWollastonite

High aspect ratio is best

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Anisotropic fillers can improve yield strength

Phantom Plastics™

Flow direction Flow direction Flow line

Fillers give weld lines – weak points that cause failure

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Weld / flow lines

Phantom Plastics™

More anisotropic fillers give lower weld line strength Tensile Yield Strength - Effect of Fillers & Weld Lines

0

10

20

30

40

50

60

70

80

ABS PP Unfilled PP (50% CaCO3) PP (30% GF)

Without weld linesWith weld lines

Yiel

d St

reng

th (M

pa)

Courtesy of Electrolux

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Fillers and weld line strength

Phantom Plastics™

Always plot properties versus volume % filler to get straight lines!

0

1

2

3

4

5

0 10 20 30 40 50 60 70 80 90 100

Talc in PP

Magnetite in PP

Tungsten in Nylon

Weight % Filler

Den

sity

g/c

m³

ρc = ρf x ρp ρpmf + ρf x (1-mf)

ρc - density of the composite ρf - density of the filler ρp - density of the polymer mf - weight fraction of filler (between 0 & 1)

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Composite density and filler loading

Phantom Plastics™

1 weight % air halves the mass of the material

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0% 20% 40% 60% 80% 100%

Density versus weight percent filler

Filler Concentration (weight %)

Com

posi

te D

ensi

ty (g

cm-3

)

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Density versus weight % air as a filler

Phantom Plastics™

Polymer   Melt Density (gcm-3)  

Mass Specific Heat of melt (kJ/kg.K)  

Volume Specific Heat (kJ/litre.K)  

PES   1.48   1.3   1.9  PVC-U   1.15   1.5   1.7  PET   1.15   1.6   1.8  Polystyrene   0.88   1.8   1.6  Polycarbonate   1.01   1.8   1.8  SAN   0.92   1.9   1.7  PMMA   1.01   2.0   2.0  PPO   0.92   2.0   1.8  ABS   0.89   2.1   1.9  PBT   1.12   2.1   2.4  Acetal / POM   1.22   2.5   3.1  PA 6   0.95   2.7   2.6  PA 6,6   0.97   2.7   2.6  PP   0.85   2.7   2.3  LDPE   0.79   3.2   2.5  HDPE   0.81   3.2   2.6  Aramid Fibers*   1.45   1.42   2.1  Average   ---   ---   2.1  

Average is 2.1 kJ / litre.K Volume specific heat capacity of polymers

Source: Polypropylene The Definitive User’s Guide and Databook except *Handbook of Fillers

Phantom Plastics™

Average is 2.1 kJ / litre.K

Volume specific heat capacity of mineral and metallic fillers

Mineral or Metal   Density (gcm-3)  

Mass Specific Heat (kJ/kg.K)  

Volume Specific Heat (kJ/litre.K)  

BN (hexagonal)   2.25   0.794   1.8  

Quartz   2.65   0.8   2.1  

Silver   10.5   0.188   2.0  

Talc   2.75   0.82   2.3  

Tungsten   19.35   0.088   1.7  

Beryllium Oxide   2.85   1.03   2.9  

Average   ---   ---   2.1  

Source: Handbook of Fillers

Phantom Plastics™

Impact resistance is an energy (area under the curve) not a strength

0 0 2 4 6 8 10 12 14

500

1000

1500

2000

2500

J = total energy

Deflection (mm)

Forc

e (N

ewto

ns)

Standard velocity 4.4 ms-1

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Penetration test

Phantom Plastics™

Take impact resistance results in context and with a grain of salt

VINCENT, P. I . Impact Tests and Service Performance of Plastics, Plastics Institute, London (1971).

0 0.25 1

12

16

28

32

40

Acrylic

Notch Tip Radius (mm)

Izod

Impa

ct R

esis

tanc

e (k

Jm-2

)

2 8 32 16 0.5 4

36

24

20

8

4

ABS

Acetal (POM)

Nylon PVC

PC 3mm 8.6J, 6mm 1.6J so suppliers only show thin specimen results

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Notch radius sensitivity

Phantom Plastics™

The notch provides crack initiation and helps consistency

Notched Izod Notched Charpy

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Impact test methodology

Phantom Plastics™

Cost Euro / ton

Cost Euro / litre

Size CaCO3 d50 microns

100 0.27 ~ 2

200 0.54 ~ 1

300 0.81 ~ 0.5

400 1.08 ~ 0.3

500 1.62 ~ 0.1

Prices must be compared on a per unit volume basis

Approximate Polymer prices € / L

PP 0.68

PE 0.74

PS 0.84

HIPS 0.85

PVC 0.98

PET 1.4

ABS 1.5

Nylon 2.7

PC 2.8

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CaCO3 – particle size & cost

Phantom Plastics™

Fair impact resistance, higher stiffness, retained strength, lower cost

0 0

Impact modifier (volume %)

Cha

nge

in p

rope

rty

20 40 60 50 10 30

Tensile strength

Materials cost

Melt viscosity

Impact resistance

Incr

ease

D

ecre

ase

Modulus

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Filled polymers property profile

Phantom Plastics™

n  Plastics Materials 7th Edition, J. A. Brydson, Butterworth-Heinemann 1999

n  Plastics Additives Handbook, H. Zweifel, Hanser/Gardner, 2001

n  Particulate-Filled Polymer Composites, 2nd Edition, Roger Rothon (Ed.), RAPRA, 2003

n  Functional Fillers for Plastics, Marino Xanthos (Ed.), Wiley-VCH, 2005

n  www.specialchem.com great resource for polymers, additives and more

n  www.matweb.com free searcheable polymer properties data

n  www.eng-tips.com free polymer & composites advice

n  www.phantomplastics.com consultancy services – new materials, additives, training and problem solving

Some excellent resources I use every day

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Further reading

Phantom Plastics™