Research areas

Natural product isolation and total synthesis.

Chemistry and biology of free radicals

Dr. Andrew ClarkSenior Lecturer in Synthetic Chemistry

Development of synthetic methodology using copper, iron and rutheniumFunctional Genomics / Chemical Genetics / InteractomicsUse of plants in renewable plastics manufacture

Use of plants in renewable plastics manufacturePOLYMERS and COMPOSITES

Resins/MonomersNormally made from organic chemicals which are petrochemicalin origin.

StrengthenersNormally a fibre incorporated into the polymer to increase mechanical strength.

FillersCheap organic or inorganic materials used to bulk the polymers and to alter physical properties

Plant oils e.g. rape oil, linseed oil, sunflower oil, soya oil

Plant fibres e.g. hemp, flax, jute, miscanthus

Plant protein / waste e.g. rape meal

ADVANTAGES OF PLANT PRODUCTS OVER PETROCHEMICALS

Non-toxic,

Biodegradable,

Non-polluting in water courses,

Sustainable,

Recyclable?

Besides a competitive price, the chemical industry also wants improved or new properties from end products derived from vegetable oils

Vegetable Oils as Polymer Feedstocks (monomers)

Rapeseed oil Euphorbia oil

Jute Hemp

Plant fibres for composites

0

500

1000

1500

2000

2500

Ar amid Car bon Flax E -glass Hemp

: Specific tensile strengths of synthetic and natural fibres

hydroxylatedmonomers

OH

OH

POLYURETHANESFlexible and rigid foamselastomers and extrusions,coatings, adhesives

10 6 tonnes per annum

POLYESTERSFlooring, autobody repair, boat hulls

Epoxidisedmonomers

O

O

EPOXY RESINSProtective coatings, adhesivesflooring, plasticizers, foams

COMMON MONOMER FEEDSTOCKS

hydroxylatedmonomers

POLYURETHANES

OH

OH

Isocyanatemonomers

NCO

NCO

catalyst

hydroxylatedmonomers

O

OO

HN

Isocyanatemonomers

Renewable sources of monomers for polyurethane synthesis

hydroxylatedmonomers

OH

OH

OH

OH

C15H29

TYPE 1CASTOR OIL

OOO

OR

OR

COR

TYPE 2CARDANOL

cashew nut shell liquidOH

C15H29NN

OH

steps

OOO

OR

OR

OR

oleic

linoleic

linolenic

Rapeseed

H2O2, W, H3PO4Room temperature

epoxideO

alcoholOHOH

acid, H2O

VernolicO

OOO

OR

OR

OR

Euphorbia

acid, H2O

OHOH

RAPESEED

O

O

epoxidationRAPESEED

HO

HO

OH

OH

RASOR

ring openingRAPESEED

O

O

EUPHORBIA

HO

HO

OH

OH

low-EURE

ring openingRAPESEEDEUPHORBIA

OH

OH

OH

OH

OHOH

OHOH

high-EURE

epoxidation

ring openingRAPESEEDEUPHORBIA

INFRA RED OF RAPESEED AND HYDROXYLATED RAPESEED

RAPESEED

O

O

epoxidationRAPESEED

HO

HO

OH

OH

RASOR

ring openingRAPESEED

OO

O

O

RAPESEED

O

OH

HO

RAPESEED

HOOH

HOOH

OH

OH

HO

RAPESEED

HOOH

HOO

OH

OH

OH

HO

RAPESEED

HO

HO

+

OH

OH

O

O

EUPHORBIA

HO

HO

OH

OH

low-EURE

ring openingRAPESEEDEUPHORBIA

OH

OH

OH

OH

OHOH

OHOH

high-EURE

epoxidation

ring openingRAPESEEDEUPHORBIA

4000 3500 3000 2500 2000 1500 10000

20

40

60

80

100

C=O

OH

Euphorbia low-OH Euphorbia high-OH

Tran

smitt

ance

(%)

Wavenumber (cm-1)

Infra Red of modified low hydroxylated and high hydroxylated euphorbia

POLYMERISATION

THREE CLASSES of RESIN

RAPESEED HYDROXYLATED RESIN (RASOR)EUPHORBIA HIGH HYDROXYLATED RESIN (high-EURE) EUPHORBIA LOW HYDROXYLATED RESIN (low-EURE)

DI-ISOCYANATESMDITDI

COMPOSITES HEMP (H)

MISCANTHUSFLAX

JUTE (J)

COMPRESSION MOULDING

4000 3500 3000 2500 2000 1500 10000

20

40

60

80

100

C=O

OH and NH

NCO

Euphorbia-OH Euphorbia 50min Rapeseed 50min

Tran

smitt

ance

(%)

Wavenumber (cm-1)

IR spectra of 50 min cured rapeseed and euphorbia oil

0 10 20 30 40 50 60 70 80 900

20

40

60

80

100

120

140

160

180

200

Isothermal cure characteristics of MDI polymerised

rapeseed resin (50oC, 180 J/g)

RASOR

Hea

t of r

eact

ion

(del

ta H

-J/g

)

Time (min)

Differential scanning calorimetry (DSC) analysis:

0 200 400 600 8000

20

40

60

80

100 Rapeseed oil Hydroxylated oil MDI polymerised Hemp-RASOR

composite

Mas

s los

s (%

)

Temperature (oC)

THERMAL GRAVIMETRIC ANALYSIS OF MATERIALS

RAPESEED

The loss in mass as a function of temperature

0 200 400 600 8000

20

40

60

80

100 Rapeseed oil Hydroxylated oil MDI polymerised Hemp-RASOR

composite

Mas

s los

s (%

)

Temperature (oC)

0 200 400 600 8000

20

40

60

80

100 Euphorbia oil Hydroxylated Euphorbia resin Hemp-EURE

composite

Mas

s los

s (%

)

Temperature (oC)

THERMAL GRAVIMETRIC ANALYSIS OF MATERIALS

RAPESEED EUPHORBIA

The loss in mass as a function of temperature

0 200 400 600 800 10000

5

10

15

20

25

30 Neat EURE Hemp-EURE

Mas

s los

s (%

)

Degradation temperature (oC)

THERMAL GRAVIMETRIC ANALYSIS OF MATERIALS

EUPHORBIA

0 1 2 3 4 50

5

10

15

20

25

30

35

40

45

HEURE low-OH HEURE high-OH Alk HEURE high-OH

Tens

ile st

reng

th (M

Pa)

Strain (%)

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.50

10

20

30

40 Untreated HRASOR Alk HRASOR

Tens

ile st

reng

th (M

Pa)

Strain (%)

Untreated and alkali treated hemp-EURE and hemp-RASOR composites

Compositetype

Fibre volume(%)

Tensile strength(MPa)

Young’s Modulus(GPa)

Composite density(Kg/m3)

Impact strength(kJ/m2)

ILSS(MPa)

HEURE-low-OH

21.05 22.91 (1.06)

2.31 649.55 18.81(2.17)

3.12

HEURE-high-OH

18.89 26.56 (1.85)

2.78 625.07 7.03(1.13)

3.49(0.45)

HRASOR 19.92 38.84 (2.21)

3.40 697.09 9.25(1.21)

3.88(0.45)

AHEURE-high-OH

20.39 34.69(3.76)

3.13 675.46 9.15(1.64)

4.73(0.76)

AHRASOR 19.20 23.82(2.96)

2.35 633.16 10.47(2.01)

3.81(0.43)

JEURE-high-OH

23.77 55.52(2.60)

4.26 658.59 10.60(2.27)

4.95(0.43)

JRASOR 23.74 46.38(3.37)

3.89 704.93 13.70(1.95)

3.99(0.82)

AJEURE-high-OH

22.69 26.76(2.23)

2.52 663.34 8.33(0.88)

3.45(0.45)

AJRASOR 22.70 26.84(1.60)

2.61 655.23 13.34(1.78)

3.55(0.66)

1 2 3 40

10

20

30

40

50

60

AJRASORJRASORAJEUREhigh-OH

JEUREhigh-OH

Tens

ile st

reng

th (M

Pa)

0

2

4

6

8

10

12

14

16

18

20

22

ALkhemp-RASOR

UnhempRASOR

Alkhemp-EUREhigh-OH

Unhemp-EUREhigh-OH

Unhemp-EURElow-OH

Impa

ct st

reng

th (k

J/m

2 )

SCANNING ELECTRON MICROSCOPY

RAPESEED PU RAPESEED-HEMP COMPOSITE

EUPHORBIA PU EUPHORBIA-HEMP COMPSITE

WEATHERABILITYNO evidence of major decomposition after

6 months simulated Solar UV radiation

BIODEGRADABILITYSamples buried in bags 6 x 6 cm (pore size 20 micron)

Bags recovered after three and six weeksWeight loss and colonising flora analysis

Sample Weight loss after 6 weeks [%]

Euphorbia polyurethane (EURE) 15.2

Rapeseed polyurethane/hemp composite (hemp-RASOR)

52.2

Euphorbia polyurethane/hemp composite(hemp-EURE)

50.3

Rapeseed polyurethane (EURE) 12.4

123 4 5 6 7 8 910111213

1 = ladder DNA, 2-5 = soil DNA, 6-9 = 3 wks, 10-13 = 6 wks

6, 10 = microflora DNA from EURE7, 11 = microflora DNA from hemp-RASOR8, 12 = microflora DNA fromhemp-EURE9, 13 = microflora DNA from RASOR

BIODEGRADABILITY

RASOR SEM

1= 3 weeks hemp-EURE2= 3 weeks hemp-RASOR3= 6 weeks hemp-EURE4= 6 weeks hemp-RASOR

1 2 3 4

Economics.

Cost of oil production per kiloEuphorbia lagascae £1.61Rapeseed oil £2.11Castor oil £1.21 * not including import costs

Cost of complete polyurethane production per kiloEuphorbia lagascae £1.54Rapeseed oil £1.88Petrochemical £2.50-£9.50

Energy required in monomer production 1.9kg of fossil fuel per kg of monomerEquates to 3.1 kg of CO2 emissions per Kg of monomer

A range of materials from rapeseed oil and euphorbia oil have been prepared and analysed.

Properties of materials produced differ depending upon the type of oil used.

Fibre composites of resins give superior properties to resins alone.

Biodegradability may be controllable

The increased range of materials available from this project will broaden the portfolio of potential industrial applications of materials from renewables which should lead to an increased value added market for fibres and oil crops in the UK agricultural sector.

Euphorbia lagascae is a potential new crop for renewable materials production

CONCLUSIONS AND RELEVANCE

Future work

In depth biodegradation studies. Can we control rate of degradation?

Use of other oilseed crops and fibre crops.

Use of fillers (rapemeal)

Portfolio of materials from renewables to showcase to industry

Chemistry Department, University of Warwick, Coventry, CV4 7ALDr. A. J. Clark, Project leader, Chemistry, monomer productionDr. L. Mwaikambo, Polymer synthesis and characterisationProf. T. J. Kemp, WeatherometryMrs. A. Mohd Rus, Weatherometry

Advanced Technology Centre, Warwick Manufacturing Group, University of Warwick, Coventry, CV4 7AL, Dr. N. J. Tucker, Project leader, Composites, mechanical testing

Biological Sciences, University of Warwick, Coventry, CV4 7AL, Dr. M. Krsek, Biodegradability Prof. E. M. H. Wellington, Biodegradability

ADAS (Euphorbia supplier) Mr. D. Turley, Formally of ADAS, High Mowthorpe, Duggleby, Malton, N Yorks, YO17 8BP.Dr. R. M. Weightman ADAS Consultancy Ltd, Battlegate Road, Boxworth, Cambs, CB3 8NN

ACKNOWLEDGEMENTS