Can Plastics be Sustainable? · History of plastics • Polyamid / nylon First synthesis 1935...

This project is implemented through the CENTRAL EUROPE programme co-financed by the ERDF

www.plastice.org Gimnazija Idrija, April 10, 2013

Can Plastics be Sustainable?

Andrej Kržan, National Institute of Chemistry, Ljubljana

andrej.krzan@ki.si

Plastics

• Large group of materials

• Wide use and growth

• An ambivalent relationship (love/hate)

Are Plastics good or bad?

• is it safe?

• does it harm health/environment?

•What is the (best) way forward?

Goal:

To show how plastics can be(come) sustainable

Plastics – an unwanted friend

Polymer vs. Plastics

• Polymer: a chemical substance

- High molar mass

- Composed of repeating units

(monomers)

• Plastics: a material

- Formulated and prepared for use

- Main component are polymers

History of plastics

• Natural materials - limitations

properties, availability, processing

• Search for new materials that are:

- simpler for processing

- have “good“ properties

- cheap

Nitrocellulose - first plastic

- Made from a renewable resource

- 1851 colloidon (viscous solution)

- 1862 Parkesine (first plastic)

- 1869 Celluloid Hyatt

(first commercially succesful plastic)

History of plastics

• Initially use of natural raw materials

proteins, cellulose, oils, phenol, formaldehyde

• Emergence of petrochemistry, new raw materials (kerosine 1840)

• Development of understanding:

Hermann Staudinger 1920 (Nobel prize 1953)

A polymer is a substance of high molar mass

composed of repeating units.

• Poliethylene

1898 chance discovery, heating of diazomethane

1933 ehylene at high pressure, 1935 repeatable

1939 production for military use

1953 Ziegler Natta catalysts for production at low pressures

UHMWPE

History of plastics

• Polyamid / nylon

First synthesis 1935

Fibers prior to 2nd WW 80 % cotton, 20 % wool

1945 25 % artificial fibers

• Polystyrene

First synthesis 1839

Production 1931

Foamed (expanded) PS (EPS) 1949

Use

• After 2nd WW

• Extremely fast growth

• 280 million tons 2011

• 5 commodity plastics > 75 %

• HDPE, LDPE, PP, PVC, PET

Uses

• Use in all areas – almost irreplaceable

• Basis for our modern lifestyle:

safety, food, health, accomodation, entertainment…

Use

• Uporabe na vseh področjih

Future uses

• Polymers are entering into new uses…

(medicine, electronics, technology, energy, construction)

…and give answers to important challenges

• Polymers = lowering CO2 emissions

- sustainable

- unsustainable

Sustainability from use

• Insulation

• Lower mass (transport + vehicles)

• Lower food waste

• Production of green energy

• Replacement of more burdening materials

Sustainable

Raising sustainability through better (sensible) use

• Efficient use – product mass

• Reuse

X times 100%

• Recycling

• Energy use (incineration)

• Don’t use!

Plastics increasingly banned? Yes: 2 problems 1. Pollution with plastic waste

• Durable – unnatural materials – non-degradable • Omnipresent due to large use

2. Based on non-renewable resources • Inherently unsustainable

But plastics are bad?

Durable and harmful in environment

Waste: many options

… some ends in environment

EU 50 % landfilling

Waste

Based on fossil resources

A cycle that doesn’t function!

(CO2 – environmental aspect)

Price of oil in future?

(economic aspect)

Production

Crude oil

Natural gas plastics

CO2

waste

10 years

biomass

106 years

Bioplastics

Bioplastics = Biodegradable and/or biobased plastics

(European Bioplastics – used in industry)

Biodegradable

Biobased

Torej:

Source can be renewable (biomass) or non-renewable (fossil)

Material can be biodegradable or nondegradable

Biodegradable ≠ biobased

Biodegradable plastics

• Functionality of artificial polymers

• In certain time and under certain conditions

degrade to natural harmless substances

• Degradation includes biological step!

Biodegradation means that (micro)organisms digest BP.

So it makes sense to use natural or similar building blocks

By source:

• natural polymer (starch, collagen, chitosan...)

• modified natural polymer (viscose, methyl cellulose..)

• synthetic polymers (PGA, PLA, PCL ...)

Thermoplastic starch

Polymer structure of starch is retained but granular structure desroyed through application of heat, mixing and plasticisers (e.g. water, glycols)

Used in composites, blends and multi-layer materials

Blends with PCL, PHA etc.

Biodegradable

Collection of organic waste, vapour permeable packaging

Mater-bi (Novamont) cap. 60.000 t/a Foamed starch for packaging

L. Averous, University Strasbourg:

www.biodeg.net/biomaterial.html

Polylactic acid = Polylactide

Aliphatic polyester

Monomer produced by

fermentation

Chemical polymerization

- co-polymers

Natureworks (US)

cap. 140.000 t/a

Purac (NL)

Biodegradable

C

C

O

C

C

O

O

O

H

H

CH3

CH3

C

C

O

C

C

O

O

O

H

H

CH3

CH3

C

C

O

C

C

O

O

O

H

H

CH3

CH3

LL-Laktid

(mp 97 C)

LD-Laktid

(mp 52 C)

DD-Laktid

(mp 97C)

Polyhydroxyalkanoates

• Natural thermoplastic aliphatic biopolyesters

• produced by bacteria

• Monomers: β-hydroxy acids

• Large variety of structures

• - Poly(β-hydroxy butyrate)

• - Poly(β-hydroxy butyrate-co-valerate)

• - Poly(β-hydroxy butyrate-co-hexanoate)

• etc

• Current production based on sucrose, glucose

• Established methodology using waste sources

• - whey (lactose, salt conditions)

• - glycerol

• - bone and meat meal (N source)

• - animal fats

Synthetic polyesters

Polyestes – hydrolysis of ester bond

(kondensation polymers)

Aliphatic polyesters (no aromatic groups) kot PHA

PBS polybutylene succinate

PBSA polybuthylene succinat adipate

PCL polycaprolactone

Aliphatic aromatic polyesters

Modifikacations of PET

PBAT polybuthylene adipate terephthalatetalat

PBMAT

(Ecoflex BASF, Eastar bio)

Wter soluble polymers

PVOH polyvinylalcohol

EVOH ethylenevinyl alcohol (O2 $$)

Biodegradation

• Degradation must be complete

• Effect of abiotic and biotic factors

• First stage: Fragmentation

macroscopic degradation and conversion to oligomers

• Second stage: Mineralization

digestion by microorganisms

Chemical mehanisms

• hydrolysis

• oxidation

(both can be enzimatic)

• biodegradationcija

• fotodegradaci

• oksidacija

• termična degradacija

• degrad. zaradi stresa

...itd

Naravni krogotok snovi

Degradation

Measurement

• Degradation is always a question of rate

>> need to set conditions and limits

>> standards

• Unchanged natural materials biodegradable by definition

Basic principle

• conversion of carbon into CO2

Testing for degradation

Respirometry

Standards and Certification

• Standards for establishing biodegradability (anaerobic, aerobic, in soil, in water…), composting, toxicity…

• Certificates based on standards • Guarantee for consumer • Use of labels • cooperation between systems Examples of certification labels:

Biobased plastics

CO2 neutral

Biobased plastics are not always biodegradable

Approach:

- Synthesis of building blocks (basic chemicals) from

bioresources

- Replacement of same or similar chemical chemical from

fossil sources

- Fermentation and various chemical conversions

- Biorefineries

Crude oil

Natural gas plastics

CO2

waste

10 years

biomass

106 years

• “Back to the future” Not new !!! How polymer chemistry got started:

• 1869 Nitrocellulose Hyatt Billiard balls

• 1897-1900 Galalith Casein + formaldehyde

• 1930 Nylon 11 11amino-undecanoic acid from castor oil

• 1940’s Henry Ford Soy based phenolic plastic

• Driver: only resource-convenient resource-environmental aspect

Historically

1. generation: food and feed sources

short term solution

2. generation: non-food and waste resources

wood, straw, waste

3. generation: microorganisms

algae, GMO?

Renewable resources

Nature (2008), p. 891

from CO2 in H2O

Bio Polyethylene

Biobased, nondegradable

• Equivalent to PE from fossil sources

-CH2-CH2-CH2-

• 100 % biobased

• Not biodegradable

• Braskem 2009, 200.000 t/a

• Dow Sovay

• Efficiency of ethanol fermentation?

Sugar cane

fermentation, distilation

Ethanol

dehydration

Ethyilene

polymerization

PE

Bio PET

• Bio PET / Coca Cola, Heinz: on the market

• 30 % bio C TA EG PET

Bio

+ =

Petro

⌃ ⌃

Bio PET

• Bio PET / Coca Cola, Heinz: in development

• 100 % bio C

• Partner for TA: Virent

• BTX also for:

PS, PA, PC, PU,

Phenolic resins

EG

Bio

+ =

⌃ ⌃

Bio

TA PET

New polymers

• Isosorbide (Roquette, F)

Polyethylene isosorbide terephthalate

PU

Isosorbide polycarbonate

Polyisosorbide succinate 100% biobased

Produced in a …

Biorefinery

Bioeconomy

- Very active development

- A number of players

- Preparing to have an alternative to oil

Sources

- www.eurobioref.org

- IEA Bioenergy report: Bio-based Chemicals,

Value added products from biorefineries

A GREEN INDUSTRIAL REVOLUTION IS TAKING PLACE

Biobased monomers

New and Old!

• 1,3 propanediol (DuPont, 45.000 t/a, Sorona)

• 1,4 butanediol (BDO)

• succinic acid

• levulinic acid

• glycerol

• furan dicarboxylic acid

• polyols based on soy oil

• Olefin metathesis: plant oiljs waxes, funktional oils, lubricants

Approach “Direct replacement for chemicals from fossil sources”

• Neeed for success: technology, low prices of resources, high price

of oil

Standards and measurement

Currently one established standard:

ASTM D6866

- EN standard is new

• Measuring the ratio C12 / C14

C14 is formed in atmosphere and is

characteristic of all renewable

(biological) material

in fossil sources its concentration is low

• C14 t1/2 = 5730 let

• After 50.000 years C14 conc. very low

Certification

Certification based on ASTM D6866 standard

Biobased carbon content (0-100 %)

Biobased C content marked on certification logos

Advantages of Bioplastics

In production: use of renewable resources

towards CO2 neutrality

CO2

footprint

After use: bioconversion into natural degradation products

… plastics can be a part of the natural material cycling

NATURE

P

CO2

Biodegradable vs. biobased?

Will a product made from biodegradable plastics go into

composting? - labeling?

- does biodegradability make sense?

If production is efficient biobased plastics always bring an

advantage

Conclusion

Plastics can have

substantial contribution to higher sustainability

Unwanted friend should become our partner

www.plastice.org

www.sustainableplastics.eu

andrej.krzan@ki.si

Thank you!