Anhydride Cure: Stoichiometric weight of MHHPA, 1 phr 2-ethyl-4-methylimidazole, 145 oC 15 hrs, 175 oC 1 hr. Cationic Cure: 3 phr BF3 ethylamine,150 °C 3 ...
Synthesis and Properties of Glycidyl Esters of Epoxidized Fatty Acids Rongpeng Wang & Thomas Schuman Department of Chemistry Missouri University of Science and Technology (Formerly University of Missouri-Rolla)
A Sustainable Polymer Industry
Sustainability “Acting responsibly to meet the needs of the present without compromising the future generations to meet their own needs.”*
Fossil Raw Materials Supply
2
Foreseeably limited Rising cost of crude oil
Environmental & Health Issues Vegetable Oils Bio-renewable High availability Versatile applications *: United Nations Conference on Environment & Development
General Routes for Synthesis of Vegetable Oil Based Polymers Radical
Alkyd Resin
Cationic
Vinyl Copolymer
Direct Polymerization
Epoxy Resin Vegetable oil Functionalization
Chemical Transformation
3
Epoxidation
Polyurethane Polyols
Transesterificaiton
Acrylated Epoxidized Soybean Oil
Oxidative Cleavage
Diacid/Diols
Metathesis
ROMP
Epoxidized Vegetable Oils in Epoxy EVO
Based Epoxy Resins
Cationic, UV, thermal latent initiator cure Aliphatic, aromatic, cycloaliphatic polyamines Anhydride
EVO-Commercial
4
Epoxy Blends
Reactive diluent Improve the impact strength
Commercial Epoxy Resin vs. ESO/ELO
5
Problems of Epoxidized Vegetable Oil Based Thermosetting Polymer
Crosslink Density
Poorer performance
6
Lower reactivity of internal epoxy groups Low oxirane content Saturated fatty acid components
Thermal, especially a low glass transition temperature Mechanical properties Higher viscosity (oligomeric) Compatibility if used as diluents for epoxy
Application of Epoxidized Vegetable Oils
Co-plasticizers & stabilizers for poly (vinyl chloride)
Biodegradable lubricants, coatings, inks
Non-structural applications
Strength
Glass transition temperature
Tg must be appropriately higher than the temperature of its intended work environment! 7
The Importance of Glass Transition Temperature
Tg Tg
8
Stevens, M. P., Polymer Chemistry : An Introduction; Oxford University Press 1999.
Synthesis Route to Epoxidized Glycidyl Ester of Vegetable Oil (EGE)
9
General Structure of an EGE
10
General Physical Properties of EGE Epoxy Structure
Oxirane Oxygen* (g/100g sample)
Epoxy Equivalent Weight (EEW)
Viscosity 25 oC (mPa∙S)
EGS ESO EGL
10.1 6.9 12.0
158 232 134
70 450 85
ELO
9.3
171
800
DGEBA
8.6
188
13000
* HBr titration: AOCS method Cd 9-57
11
EGS: Epoxidized glycidyl soybean ester
ESO: Epoxidized soybean oil
EGL: Epoxidized glycidyl linseed ester
ELO: Epoxidized linseed oil
Polymer Glass Transition Temperatures EGEs (EGS or EGL) vs. EOs (ESO or ELO) Oxirane Oxygen, %
Tg, °C (BF3 ethylamine cure) 125.9
Tg, °C (MHHPA cure)
105.6 93.8 78.6 65.7 45
47.84 33.6
24.91 10.1
9.11 2.92
6.96
11.96
11.52
9.22 13
-4.97 EGS 12
EGS-S*
ESO
EGL
* including saturated fatty acids content, DSC: 20 oC/min
EGL-S*
ELO
Glass Transition Temperatures As a Function of Oxirane Content 140 120 MHHPA
BF3-ethylamine
Tg oC
100 80 60 40
20 0
6
7
8
9
10
11
12
-20
Oxirane Content, % Anhydride Cure: Stoichiometric weight of MHHPA, 1 phr 2-ethyl-4-methylimidazole, 145 oC 15 hrs, 175 oC 1 hr Cationic Cure: 3 phr BF3 ethylamine,150 C 3 hrs, 185 C 1 hour.
Dilution of EPON® 828 by EGS/ESO Diluent
Reactive diluent content (phr)
14
Diluent to reduce Epon 828 to 1000 cp (25 oC)
Xylene
7 wt%
Benzyl Alcohol
12 wt%
n-Butyl Glycidyl Ether
8 wt%
C12-C14 Glycidyl Ether
14 wt%
Neopentyl Glycol Diglycidyl Ether
22 wt%
Cresyl Glycidyl Ether
19 wt%
ESO
55 wt%
EGS
32 wt%
Technical Data Sheet of Momentive EPON Resin 828
DSC Analysis EPON 828-EGS/ESO-MHHPA Cure
ΔH= 230 J/g
ΔH= 321.5 J/g
ΔH= 355.3 J/g
15
Stoichiometric weight of MHHPA, 1 phr 2-ethyl-4-methylimidazole, Heating Rate: 10 C/min
Dynamic Thermograms of DGEBAEGS/ESO-MHHPA Systems
12 oC 15 oC
60 oC
16
DGEBA-EGS Blend
DGEBA-ESO Blend
Glass Transition Temperature (Tg) ESO/EGS Anhydride Blends
Tgo : Tg of uncrosslinked polymer 1/Mc : Crosslink density
Reactive diluent content (phr) 17
Stoichiometric weight of MHHPA, 1 phr 2-ethyl-4-methylimidazole, 145 oC 15 hrs, 175 oC 1 hr
Glass Transition Temperature (Tg) Anhydride Cured Neat ESO/EGS Heating rate: 20 oC/min
18
Flexural Strength EPON 828-EGS/ESO Anhydride Blends 135 125
MPa
115 105
EGS
95
ESO
85 75
65 55 0
10
30
50
70
90
Reactive diluent content (phr) 19
ASTM D790, crosshead speed: 0.5 inch/min
100
Flexural Modulus EPON 828-EGS/ESO Anhydride Blends 3100 2900
MPa
2700 2500
ESO
2300
EGS
2100 1900 1700 1500 0 20
10
30 50 70 90 Reactive diluent content (phr) ASTM D790, crosshead speed: 0.5 inch/min
100
Tensile Strength EPON 828-EGS/ESO Anhydride Blends 60 55
MPa
50 EGS 45 ESO 40 35 30 0 21
10
30 50 70 Reactive diluent content (phr) ASTM D638, crosshead speed: 0.4 inch/min
100
Tensile Modulus EPON 828-EGS/ESO Anhydride Blends 3000 2800
MPa
2600 EGS
2400
ESO
2200 2000 1800 1600 0 22
10
30 50 70 Reactive diluent content (phr) ASTM D638, crosshead speed: 0.4 inch/min
100
Conclusions
Epoxidized glycidyl ester of soybean oil (EGS)
EGS-Epon828 blend vs. ESO-Epon828 blend
Cure compatible Improved mechanical properties Higher polymer Tg
Potential applications in epoxy blends
23
Renewable & environmentally friendly High conversion efficiency & universal synthesis process More reactive High oxirane content Low viscosity
Reactive diluent Toughening agent Composite polymer matrix Coating with low VOC or 100% solids
Acknowledgement
Professor K. Chandrashekhara Department of Mechanical & Aerospace Engineering
Rama Vuppalapati Mechanical Test
Arkema Inc. Epoxidized linseed oil
Archer Daniels Midland (ADM) Linseed oil
