Bio-Based Methodologies for the Production of Environmentally - - PowerPoint PPT Presentation

SERDP & ESTCP Webinar Series

Bio-Based Methodologies for the Production of Environmentally Sustainable Materials

January 22, 2015

SERDP & ESTCP Webinar Series

Welcome and Introductions

Rula Deeb, Ph.D. Webinar Coordinator

Webinar Agenda

• Webinar Overview and ReadyTalk Instructions
• Dr. Rula Deeb, Geosyntec

(5 minutes)

• Overview of SERDP and ESTCP, and webinar series goals
• Dr. Robin Nissan, SERDP and ESTCP

(5 minutes)

• Isocyanate-Free Solid Rocket Motor Propellant Binders Inspired by Nature
• Dr. Andrew Guenthner, Air Force Research Laboratory (10 minutes + Q&A)
• Cyanate Ester Composite Resins Derived from Renewable Polyphenol

Sources

• Dr. Benjamin Harvey, Naval Air Warfare Center

(25 minutes + Q&A)

• Environmentally Friendly High Performance Bio-Based Polymers for DoD

Applications

• Dr. John La Scala, U.S. Army Research Laboratory

(25 minutes + Q&A)

• Final Q&A session

5

SERDP & ESTCP Webinar Series (#7)

How to Ask Questions

6

Type and send questions at any time using the Q&A panel

SERDP & ESTCP Webinar Series (#7)

SERDP & ESTCP Webinar Series

SERDP and ESTCP Overview

Robin Nissan, Ph.D.

Weapons Systems and Platforms Program Manager

SERDP

• Strategic Environmental Research and

Development Program

• Established by Congress in FY 1991
• DoD, DOE and EPA partnership
• SERDP is a requirements driven program

which identifies high-priority environmental science and technology investment

• pportunities that address DoD requirements
• Advanced technology development to address

near term needs

• Fundamental research to impact real world

environmental management

8

SERDP & ESTCP Webinar Series (#7)

ESTCP

• Environmental Security Technology

Certification Program

• Demonstrate innovative cost-effective

environmental and energy technologies

• Capitalize on past investments
• Transition technology out of the lab
• Promote implementation
• Facilitate regulatory acceptance

9

SERDP & ESTCP Webinar Series (#7)

Program Areas

• 1. Energy and Water
• 2. Environmental Restoration
• 3. Munitions Response
• 4. Resource Conservation and

Climate Change

• 5. Weapons Systems and

Platforms

10

SERDP & ESTCP Webinar Series (#7)

Weapons Systems and Platforms

• Major focus areas
• Surface engineering and

structural materials

• Energetic materials and

munitions

• Noise and emissions
• Waste reduction and

treatment in DoD

• perations
• Lead free electronics

11

SERDP & ESTCP Webinar Series (#7)

SERDP and ESTCP Webinar Series

SERDP & ESTCP Webinar Series (#7) DATE WEBINARS AND PRESENTERS February 5, 2015 Acoustic Methods for Underwater Munitions

• Dr. Joseph Bucaro (Naval Research Laboratory)
• Dr. Kevin Williams (APL University of Washington)

February 19, 2015 Solar Technologies

• Deborah Jelen (Electricore)
• TBD

March 5, 2015 Lead Free Electronics

• Dr. Peter Borgesen (Binghamton University, The State University of New York
• Dr. Stephan Meschter (BAE Systems)

March 19, 2015 Bioremediation Approaches at Chlorinated Solvent Sites

• Carmen LeBron, Independent Consultant
• Dr. John Wilson, Scissor Tail Environmental
• Dr. Rob Hinchee

March 26, 2015 Environmental DNA: A New Tool for Species Inventory, Monitoring and Management

• Dr. Lisette Waits, University of Idaho
• Dr. Alexander Fremier, Washington State University

12

SERDP & ESTCP Webinar Series http://serdp-estcp.org/Tools-and- Training/Webinar-Series

SERDP & ESTCP Webinar Series

Isocyanate-Free Solid Rocket Motor Propellant Binders Inspired by Nature

• Dr. Andrew Guenthner

Air Force Research Laboratory

SERDP & ESTCP Webinar Series

Isocyanate-Free Solid Rocket Motor Propellant Binders Inspired by Nature

SERDP Project WP-2406

• Dr. Andrew Guenthner, AFRL/RQRP

Agenda

• Background and motivation
• Research results to date
• Relevance and payoff
• Future plans

16

Background: Isocyanates

• Production was roughly 4 billion kg in 2000
• Isocyanates are highly reactive; aid in the

production of energetic materials

• Isocyanates are a powerful irritant and a cause
• f occupational asthma
• Sensitization can occur, with effects continuing

for many years afterward

• Cross-sensitization (e.g., dermal exposure

leading to sensitization of respiratory tract) has also been reported

• Due to their reactivity, isocyanates are not found

in nature

Source/additional information

http://www.elcosh.org/record/document/1790/d000635.pdf http://www.cdc.gov/niosh/topics/isocyanates/

17

Solid Rocket Motor Propellants

• Binder starts out as liquid, then solidifies

after mixing and casting

Image courtesy of Univ. Illinois Center for Simulation of Advanced Rockets

18

SERDP SEED Effort

• Identify cross-linking chemistries that are

ubiquitous in nature

• DNA nucleobase binding
• Thiol-based cross-linking (animal hair)
• Main goal is to demonstrate reduced risk

in potential future efforts

• Does the chemistry work?
• How do substitute chemistries affect the

properties of the propellant?

19

Results from DNA Nucleobase Polymers

• Too many unknown characteristics of self- and cross-association for

near-term development of reliable cross-linking substitute

N N N N N N N O O H H H Polymer Polymer

+

Hydrogen Bonding Complex Cross-linked Binder Adenine ---- thymine Polymer chains

• 4
• 3
• 2
• 1

1 2 3 4 5

• 100
• 50

50 100 Heat Flow (mW) Temperature (°C) DSC of Adenine Acrylate Co Butadiene TG Association / Dissocation Liquid at room temperature Cooling Heating

0.00001 1000 10000 100000 1000000 Differential Refractive Index

• Approx. MW (Polystyrene Standards)

Chromatogram of Adenine Acrylate Co Butadiene

20

Results from Thiol-ene Chemistry

• HTPB cured with 1,9-nonanedithiol at 5:1 SH / O•, 60°C, for 8

days under N2. Data point labels (left figure) indicate fraction

• f available –SH incorporated into gel, a measure of

conversion

• Glass transition temperatures remain at acceptable levels
• ver a wide range of cure conditions

21

Impact of Results on Future DoD Operations

• Elimination of isocyanates alleviates a major
• ccupational health and safety concern in the

manufacture and use of solid rocket motor propellants

• Elimination of isocyanates also mitigates

issues related to moisture sensitivity and degradation

• Replacement of isocyanates with chemical

groups that are ubiquitous will greatly reduce the risk associated with future regulation/obsolescence

• Many other DoD and DoE applications

(foams, paints, sealants) will benefit from new isocyanate-free cure chemistries

22

Future Effort and Transition Plans

• Project focus shifting towards demonstration
• f energetic propellant formulations
• If energetic formulations demonstrate

acceptable properties, then a full SERDP program utilizing thiol-ene cured binders will be proposed

• Internal efforts at AFRL would leverage any

full SERDP program

• Nucleobase-containing polymers will be

proposed as a laboratory task for the Air Force Office of Scientific Research

23

Conclusions

• DNA nucleobase technology

represents a promising but immature path to isocyanate replacement

• Thiol-ene chemistry represents

a promising candidate replacement for isocyanate cure

• Thiol-ene based propellants

may offer a variety of advantages in the manufacture

• f solid rocket motors

Acknowledgments Project team members: Mr. Michael Ford, Dr. Timothy Haddad,

• Dr. Joseph Mabry, Mr. Jacob Marcischak, Dr. Josiah Reams

24

SERDP & ESTCP Webinar Series

For additional information, please visit:

https://www.serdp-estcp.org/Program- Areas/Weapons-Systems-and-Platforms/Energetic- Materials-and-Munitions/Rocket-and-Missile- Propellants/WP-2406/WP-2406/(language)/eng-US

Speaker Contact Information andrew.guenthner@us.af.mil 760-382 3366

SERDP & ESTCP Webinar Series

Q&A Session 1

26

SERDP & ESTCP Webinar Series

Cyanate Ester Composite Resins Derived from Renewable Polyphenol Sources

• Dr. Benjamin Harvey

Naval Air Warfare Center

SERDP & ESTCP Webinar Series

Cyanate Ester Composite Resins Derived from Renewable Polyphenol Sources

SERDP WP-2214

• Dr. Benjamin G. Harvey, Naval Air Warfare

Center, Weapons Division, China Lake, CA

Agenda

• Brief overview of composites and cyanate

ester resins

• Synthesis and characterization of phenols

and cyanate esters from biomass sources

• Properties of renewable thermosetting

resins

• Bulk molding compounds/fabrication of

composite parts

• Summary and conclusions

29

Composites

Example of carbon fiber fabric Boeing 787 Dreamliner (50% by weight) composites

A composite material is the combination

• f a structural component (e.g., fibers)

and a matrix material (polymer) Composites weigh significantly less than conventional structural materials (steel, aluminum). This can result in reduced fuel usage and/or improved range for military platforms

F-35 Joint Strike Fighter (~35% composites) Example of glass fiber fabric

30

Cyanate Ester Resins

• Cyanate esters (R-OCN) cross-link by cyclotrimerization
• Higher Tgs and lower water uptake than epoxy resins
• No volatile byproducts are generated upon cure
• Resins are synthesized from bisphenols
• Renewable phenols can be derived from biomass sources. Potential benefits

include reducing petroleum use, improving synthetic efficiency and allowing exploration of new structure/property paradigms

NCO OCN

BADCY (cyanate ester synthesized from bisphenol A)

N N N O O O O O O

∆ Cross-linked thermoset with robust triazine ring linkage.

The Tg (glass transition temperature) of the thermoset derived from BADCY is 304 °C

31

High-Temperature Polymers from Biomass

Waste biomass (e.g., forestry residue) contains three main components: cellulose, hemicellulose and lignin Cellulose (glucose polymer) Biofuels, fine chemicals Hemicellulose (amorphous sugar polymer) Biofuels, fine chemicals Lignin (phenolic polymer) Rigid structures suitable for high temperature polymers

OCH3 O OH OCH3 O OH OCH3 O HO OCH3 OH HO O

32

Vanillin-Based Resins

H3CO O OH H3CO O HO OCH3 O OH H3CO HO OH O OH H3CO OH H3CO O

creosol vanillin lignin model H2/cat.

• Lignin can be
• xidized/depolym-erized to

generate vanillin; reduction

• f vanillin yields creosol
• Vanillin can also be

produced biosynthetically (yeast)

• Vanillin can be readily converted to a

bisphenol

• A new cyanate ester resin and

polycarbonate have been prepared from the bisphenol

Harvey, B. G.; Guenthner, A. J.; Meylemans, H. A. et al. Green Chem 2015 Advance Article DOI: 10.1039/C4GC01825G

33

NCO MeO OCN OMe NCO MeO OCN OMe O OH OMe

vanillin VanCy H2VanCy [Ti]

New Routes to High Temperature Resins from Vanillin

OH OH HO OMe OH OMe HO OMe OH OMe OH O MeO

ε°

McMurry Route Electrochemical Route

HO MeO OH OMe PhOCOPh O

Zn(Ac)2 ∆

MeO O OMe O O

n

Polycarbonate Synthesis Polycarbonate Properties Tg = 86 °C Mn = 3588 (GPC); 4035 (NMR) Mw/Mn= 1.9 Compound VanCy H2VanCy Tm(°C) 237 190 Tg(°C) NA 202

Harvey, B. G.; Guenthner, A. J.; Meylemans, H. A. et al. Green Chem 2015 Advance Article DOI: 10.1039/C4GC01825G

34

Cure Chemistry/Structures of Vanillin- Derived Cyanate Ester Resins

TGA data (starting from resins) of the two bis(cyanate) esters derived from vanillin; VanCy (red), H2VanCy (blue)

• Pi-stacking and increased polarity due

to the methoxy groups results in high melting points VanCy H2VanCy

Harvey, B. G.; Guenthner, A. J.; Meylemans, H. A. et al. Green Chem 2015 Advance Article DOI: 10.1039/C4GC01825G

35

Thermosetting Resins from Creosol

OH H3CO OH H3CO OH OCH3 R OH H3CO OH OCH3 H+/HCOR CNBr/NEt3

• 20°C

Zn(Ac)2/CH2O CNBr/NEt3

• 20 °C

R = H(4), Me(5), Et(6) 1

OCN H3CO OCN OCH3 OCN H3CO OCN OCH3 R N N N O OCH3 O OCH3 R N N N O H3CO N N N N N N

creosol

OCH3 O

∆ ∆ polycyanurate thermosets

5 6 4 Key properties of creosol-derived cyanate ester resins Compound 1 4 5 6 As Cured Tg (LPb, °C) 172 255 253 254 Fully Cured Tg (LPb, °C) 238 248 219 244 Wet Tg (tan δ, °C) 174 193 185 161 Water Uptake (%) 2.05 2.05 2.61 3.21

• a. For the fully cured samples
• b. LP stands for Loss Profile
• Bisphenols prepared by reaction
• f creosol with aldehydes
• Unique meta-cyanate esters with

as-cured Tgs of >250 °C

Meylemans, H. A.; Harvey, B. G.*; Reams, J. T.; Guenthner, A. J.; Cambrea, L. R.; Groshens,

• T. J.; Baldwin, L. C.; Garisson, M. D.; Mabry, J. M. Biomacromolecules 2013, 14, 771-780

As cured Tgs are higher than fully cured Tgs due to decomposition at high cure temperatures 36

Thermal Stability of Creosol-Derived Resins

TGA Data for Cured Resin Pucks Compound T5% loss in N2 (air), °C T10% loss in N2 (air), °C Char yield at 600 °C in N2 (air), % 1 317 (326) 326 (339) 33 (8) 4 360 (357) 366 (362) 35 (11) 5 330 (337) 344 (349) 28 (11) 6 329 (346) 345 (357) 27 (11)

N N N O OCH3 O OCH3 N N N OH H3CO OH H3CO

HOCN ∆ m/z = 152 m/z = 138

OH H3CO OH OCH3

m/z = 302 +

Lignin Phenols Resins Composites H2O, ∆ CO2, NH3

Electron-donation of methoxy- groups may allow for recycling IR and MS experiments show evolution of significant quantities of phenols at elevated temperature

Meylemans, H. A.; Harvey, B. G.*; Reams, J. T.; Guenthner, A. J.; Cambrea, L. R.; Groshens,

• T. J.; Baldwin, L. C.; Garisson, M. D.; Mabry, J. M. Biomacromolecules 2013, 14, 771-780

37

Deoxygenation of Creosol-Derived Cyanate Esters

• Key Question: “How do o-methoxy

groups affect the properties of renewable cyanate esters”

• Deoxygenated bisphenols can be

prepared by Pd-catalyzed elimination of sulfonates followed by demethylation of the methoxy- groups

• A new series of bis(cyanate) esters

was prepared with the cyanate ester group para to the bridging group

• These compounds allow for a direct

assessment of the impact of o- methoxy groups on the material properties of cyanate ester resins

Harvey, B. G.; Guenthner, A. J.; Lai, W. W.; Meylemans, H. A.; Davis, M. C.; Cambrea,

• L. R.; Reams, J. T.; Lamison, K. R. submitted to Macromolecules 2015 under review

MeO OH OMe R OH NCO OCN R

R = H(16), Me (17), Et(18) 4 steps

Resin – Methoxy groups Dry and wet Tg Tm Thermal stability Water uptake Impact of o-methoxy groups?

38

Effect of Deoxygenation on Cyanate Ester Properties

Effect of deoxygenation on the melting point

• f resins

Compound Tm(°C) ΔTm(°C) 4 (R = H) 125 16 (R = H) 88

• 37

5 (R = Me) 91 17 (R = Me) 105 +14 6 (R = Et) 120 18 (R = Et) Liquid (RT) <-95

Effect

• f

deoxygenation

• n

the glass transition temperature of the resins Compound Tg (as-cured)a Tg(°C) ΔTg(°C)

4 (R = H) 255 248 16 (R = H) 267 +12 5 (R = Me) 253 219 17 (R = Me) 271 283 +30 6 (R = Et) 254 231 18 (R = Et) 256 272 +18

Effect of deoxygenation on the water uptake and wet Tg

• f the resins

Compound Water Uptake (%) Δ(Water Uptake) Wet Tg Δ(Wet Tg) 4 (R = H) 2.05 184 16 (R = H) NM Unknown NM Unknown 5 (R = Me) 2.61 178 17 (R = Me) 2.11

• 19%

207 +29 6 (R = Et) 3.21 161 18 (R = Et) 1.84

• 43%

198 +37

• Deoxygenation results in significant

changes in the melting points of the resins

• Deoxygenation generates resins with

higher Tgs (both wet and dry) and lower water uptake

Harvey, B. G.; Guenthner, A. J.; Lai, W. W.; Meylemans, H. A.; Davis,

• M. C.; Cambrea, L. R.; Reams, J. T.; Lamison, K. R. submitted to

Macromolecules 2015 under review

39

Thermal Stability of Deoxygenated Resins

40 50 60 70 80 90 100 50 100 150 200 250 300 350 400 450 500

Weight % Temperature (°C)

Compound 16 Compound 17 Compound 18

• TGA data confirms that deoxygenation increases the thermal stability by 50-

80 °C

• Due to the higher thermal stability, decomposition proceeds via evolution of

small molecules (isocyanic acid, methane, CO2 and ammonia)

Harvey, B. G.; Guenthner, A. J.; Lai, W. W.; Meylemans, H. A.; Davis, M. C.; Cambrea, L. R.; Reams, J. T.; Lamison, K. R. submitted to Macromolecules 2015 under review

40

Anethole-Derived Resins

MeO MeO OMe

+

E-anethole OMe MeO OCN NCO H+ NCO OCN

• 1. hydrolysis
• 2. hydrogenation
• 3. CNBr/NEt3
• 1. hydrolysis
• 2. CNBr/NEt3

Tg = 223 °C Tg = 313 °C water uptake = 1.14% water uptake = 1.66% IsoACy CyACy

• Anethole is an abundant phenolic precursor and a significant component of

some forms of turpentine

• IsoACy is a liquid at room temperature (simplifies fabrication)

Davis, M. C.; Guenthner, A. J.; Groshens, T. J.; Reams, J. T.; Mabry, J. M. J Polym Sci Part A: Polym Chem 2012, 50, 4127-4136

41

High Tg Resins from Resveratrol

MeO OMe O H HO OMe O H HO OH OH

+ trans-resveratrol syringaldehyde

• trans-Resveratrol can be obtained

from grape skins, Japanese Knotweed or even via biosynthetic routes in yeast.

• New synthetic methods have been

developed for synthesizing trans- resveratrol from renewable phenols like syringaldehyde (deciduous trees)

Cash, J. J.; Davis, M. C.* et al. Polym Chem 2013, 4, 3859- 3865

OH HO OH OCN NCO OCN

trans-resveratrol H2ResCy

OCN NCO OCN

ResCy

New synthetic routes to trans-resveratrol 42

Properties of Resveratrol-Derived Cyanate Esters

Compound Dry Tg Tg (Post- cure) Wet Tg Water Uptake Char Yield ResCy 290 >350 202 7.91% 74 H2ResCy 334 334 242 2.33% 70 H2ResCy/LECy >350 >350 242 2.50% NM LECy 291 295 239 1.75% NM

• ResCy does not cure completely leading to a lower initial cured Tg and high

water uptake due to the low conversion

• Post-cure of ResCy yields a thermoset with a Tg>350 °C
• H2ResCy appears to cure completely giving a Tg of 334 °C
• Blending H2ResCy with LECy improves the processability and yields a

material with a higher Tg

• High char yields and extemely low heat release classify ResCy and

H2ResCy as ultra-fire resistant polymers

Cash, J. J.; Davis, M. C.* et al. Polym Chem 2013, 4, 3859-3865

43

Cyanate Ester Resins from Eugenol

HO OMe HO OMe OH OMe HO OMe OH MeO

Eugenol

[Ru] Ru PCy3 PCy3 Ph Cl Cl

[Ru] =

Pd/C H2 (40-50 psi) NCO OMe OCN MeO CNBr, NEt3 O OMe O OMe N N N

polycyanurate thermoset

no solvent

∆

• 20 °C
• Eugenol is a significant component of clove oil
• A bisphenol can be readily synthesized by olefin

metathesis

• The resulting thermoset combines both rigid (aromatic)

and flexible (alkyl chain) groups. Potential to increase toughness while maintaining an acceptable Tg

Harvey, B. G.; Sahagun, C. M.; Guenthner, A. J.; Groshens, T. J.; Cambrea, L. R.; Reams, J. T.; Mabry, J. M. ChemSusChem 2014, 7, 1964-1969

44

Network Formation with Eugenol- Derived Polymers

OCN OMe NCO MeO O MeO O OMe O

Eugenol Tg = 71 °C Tg = 186 °C ∆ Homogenous Network Formation Single Tg (132 °C)

• Combining 20% eugenol-derived

polycarbonate with the cyanate ester did not significantly affect the cure reaction

• Small Angle Laser Light Scattering revealed

that no phase separation occurred upon cure (bottom left).

• A single Tg was observed by TMA (top right)

Harvey, B. G.; Guenthner, A. J.; Yandek, G. R.; Cambrea, L. R.; Meylemans,

• H. A.; Baldwin, L. C.; Reams, J. T. Polymer 2014, 55, 5073-5079

45

Recent Developments/On-Going Research in Renewable Cyanate Ester Resins

• Resin prepared from component of pine resin
• Excellent hot/wet performance
• Dry Tg of 224 °C; Wet Tg of 221 °C
• Water uptake of 0.7%
• We have generated liquid resins with Tgs>270 °C
• Potential to generate renewable LECy

(commercial resin that is liquid at room temperature)

• Low-cost renewable cyanate esters derived from

cashew nut shell oil

• Non-flammable hybrid resins

46

Composite Part Fabrication

• Bulk molding compounds (BMCs--thermosetting resin and

chopped carbon fiber) can offer comparable or superior mechanical properties to metals with significant weight savings

• Target application is a polar boss--provides support to the aft end
• f a rocket motor and attachment hardware for nozzle
• The coefficient of thermal expansion (CTE) of a BMC is much

lower than metals and similar to other components (i.e., composite missile case, polymeric insulation)

• Forged aluminum is expensive and the process is time-consuming
• Cyanate ester based BMCs are an enabling technology for high

performance polar bosses (higher Tg, lower water uptake compared to epoxies

Solid Rocket Motor Redesigned Polar Boss 47

Composite Part Fabrication

• A polar boss has been fabricated from 157 g of the isoanethole

dicyanate ester combined with chopped carbon fiber

• Initial testing with flat panels of the same resin system show good

mechanical properties compared to aluminum and an epoxy-based BMC

• Testing with the composite polar boss will be conducted this year

48

Conclusions

• A variety of high-performance resins with glass transition

temperatures from 180 to >350 °C have been prepared from renewable phenols

• Some of these resins outperform conventional petroleum

based resins (Tg, water uptake). In certain cases the structural diversity of the phenols simplifies the synthesis of the final resins

• The phenols used in this work can be sustainably sourced

from domestic biomass feedstocks. If produced at commercial scales, renewable cyanate ester resins could potentially be produced at a discount to petroleum-based analogs

• Many of the bisphenols developed in this work are expected

to be less toxic than bisphenol A

• Increased use of composites in weapon platforms has the

potential to increase warfighter capability (increased range and loiter time) while decreasing overall fuel consumption

49

SERDP & ESTCP Webinar Series For additional information, please visit:

https://www.serdp-estcp.org/Program- Areas/Weapons-Systems-and- Platforms/Surface-Engineering-and-Structural- Materials/Composites-Alloys-and- Ceramics/WP-2214

Speaker Contact Information benjamin.g.harvey@navy.mil; 760-939-0247

SERDP & ESTCP Webinar Series

Q&A Session 2

51

SERDP & ESTCP Webinar Series

Cyanate Ester Composite Resins Derived from Renewable Polyphenol Sources

• Dr. John La Scala

U.S. Army Research Laboratory

SERDP & ESTCP Webinar Series

Environmentally Friendly High Performance Bio-Based Polymers for DoD Applications

SERDP: WP-1271, WP-1758, WP-2402 ESTCP: WP-200617 John La Scala, Army Research Laboratory

Collaborators

• Army Research Laboratory
• Dr. John La Scala, PI
• Dr. Joshua Sadler, Chemist
• Ms. Raven Toulan, Chemist
• Dr. Craig Paquette, Postdoc
• Dr. Ian McAninch, Materials

Engineer

• Clemson University
• Dr. Amod Ogale, Co-PI
• Ms. Meng Zhang, Ph.D. student
• Jing Jin, Ph.D. student
• Drexel University
• Dr. Giuseppe Palmese, Co-PI
• Mr. Fengshuo Hu, Ph.D. student
• Dr. Xing Geng, Postdoc
• University of Delaware
• Dr. Richard Wool, Co-PI
• Kaleigh Reno, Ph.D. student
• Rowan University
• Dr. Joseph Stanzione
• AFRL
• Greg Yandek
• Army Public Health Command
• William Eck
• NAWC
• Benjamin Harvey

54

Outline

• 1. DoD motivation for

bio-based polymers

• 2. Plant oil-based polymers
• 3. Ligno-cellulosic-based thermosets

+

+

55

HO OH OH Glycerol O O Furfural O O HO OH Isosorbide

55

DoD Composites and Polymer Use

• Every year the use of

polymers and composites in DoD increases

• Improved performance
• Corrosion resistance
• Ease of maintenance
• Reduced cost
• Examples
• F14 contains ~2 wt%

composite materials

• F-22 contains ~24 wt%

composites

• JSF (F-35) contains >30

wt% composites

56

High Performance Polymers

• Process is not sustainable
• Process generates significant environmental hazards

CH3 CH3 O O OH O O OH O O n

Vinyl Ester (VE)

R O O O O O R O O O R O O O OH O O O O H

Unsaturated Polyester (UPE)

Styrene

O CH3 CH3 O O CH3 CH3 O OH

n

O O

Epoxy

Polyurethane

Kevlar Polyetheretherketone (PEEK)

PAN (Carbon fiber-precursor)

Hazardous solvents, HCN, CO, CH4, CO2

HAP

Haz. chemicals, & monomers

CO2

Hazardous solvents

HAP

Phenolic

Cyanate esters, bismaleimides

57

Motivation for Bio-Based Polymers

• Rising and unstable oil costs
• Creates supply chain

vulnerability of petroleum derived materials, including polymers

• Environmental concerns
• Petroleum exploration and

refining

• Processing of high

performance polymers

• DoD Green Procurement

Program

• AERTA: “Reduce/Eliminate

Pollution for Compliant Composite Manufacturing and Repair”

Gulf Of Mexico Oil Spill, 2010 EXXON VALDEZ Oil Spill, 1989 Prestige oil spill, 2002

58

Lignin derivatives Vanilin (Lignin derivative) Soybeans Chitin

Carbohydrates

Cellulose Lignin Protein

Monomer chemistry and analysis Polymerization

Bio-fibers Bio-Based Polymer Networks

Paradigm Change in Polymer Manufacture

59

Balance of Properties for Thermosets

500 1000 1500 2000 2500 3000 20 40 60 80 100 120 140 160 Temperature (oC) E' (MPa) 50 100 150 200 250 E" (MPa)

Processibility

time viscosity 500 cps Load Modulus Load at failure Displacement

Tg Fracture Toughness Stiffness and Strength

Epoxy VE UPE

VE ($2-$3/lb)

Cost

Epoxy (>$10/lb) UPE (<$1/lb)

Resins have a trade-off among 4 basic properties and cost

Tg: 120-250 °C

Toughness > 100 J/m2

Unclassified

Modulus: 2-3 GPa at 25 °C Viscosity of 500-10,000 cP at 25°C Strength > 100 MPa

60

Outline and Renewable Choice

• Triglyceride-based polymers
• Fatty acid based polymers

O O O O O O

• Carbohydrate-based polymers
• Lignin-based polymers

O O OH O O

Methacrylated Fatty Acid (MFA)

Higher performance – bulk vs. additive component

Cellulose Lignin

OH O CH3

61

Methacrylated Fatty Acids (MFA)

• Fatty acid unsaturation sites
• Chain transfer to allyl groups
• Reduces extent of cure and cure

rate

• Increasing fatty acid length
• Decreases Tg
• Increases viscosity

+

AMC-2, 50ºC for 4 hrs

OH O

Lau

O O O

GM

O O OH O O

MFA Or Oct

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 50 100 150 200 250 300 Reaction Time (min) Conversion, α

O O R O O R O O R

62

FAVE Resins

• MFA
• Non-volatile and inexpensive
• Copolymerizes with styrene and vinyl ester
• Soluble in VE and UPE
• Increases renewable content in polymers
• Reduces VOC/HAP emissions by 55-78%

+

O O O OH CH3 CH3 O O OH CH3 CH3 O O O OH n

Vinyl Ester Styrene (10-25 wt%) Commercial Resins Low VOC ~ 33 wt% Sty Standard ~ >40 wt% Sty

FAVE: Fatty Acid-Based Vinyl Ester Resin

O O OH O O

MFA (10-15 wt%)

63

Benefits of MFA/FAVE

50 100 150 200 250 300 10 20 30 40 50 Styrene Content (wt. %) GIC (J/m2) 65% VE 55% VE

0.4 0.5 0.6 0.7 0.8 0.9 1 10 20 30 40 50 60 Time (hrs) Normalized Mass Loss (g/g) FAVE (0% styrene) FAVE (20% styrene) commercial VE (45% styrene)

MFA Commercial resin FAVE

• MFA monomers themselves produce no

emissions

• Low HAP resin systems reduce emissions

by 25-75%

• MFA enables higher resin

toughness 64

20 40 60 80 100 120 140 160 15 35 Tg (oC) or Strength (MPa) MFA Content Tg Strength

Tradeoffs with MFA/FAVE

• Samples have the same VE content (65%)
• Varying styrene and MFA content
• Increasing MFA content reduces performance
• Acceptable performance can be achieved at moderate MFA/styrene

contents

0% styrene 35% styrene

1 10 100 1000 10000 10 20 30 40 Viscsity (cP) MFA Content (wt%)

500 cP

65

Composite Fabrication

• Liquid molding of resins into fiber pre-form via vacuum

assisted resin transfer molding (VARTM)

66

Composites Properties

• FAVE composites have similar properties vs. composites made from

baseline VE and epoxy resins

• Measure composite properties using numerous reinforcements
• Performed accelerated aging of composites and exposure to fluids

0.5 0.6 0.7 0.8 0.9 1 1.1 Strength Modulus SBS Tg Normalized Property VE FAVE FAVE-HT

67

Dem/Val of FAVE

68

FAVE Success

• ESTCP Weapons Platform

Project of the Year 2010

• SERDP Weapons Platform

Project of the Year 2005

• Transitioned technology to

Dixie Chemicals for commercial and DoD use

• Numerous patents and

publications

• We can use “bio” to make high performing composite materials
• But…we are limited in the amount we can use and still maintain

high performance

Low VOC composite

O O O OH CH3 CH3 O O OH CH3 CH3 O O O OH n

Bimodal blends and other chemically modifications Soybeans

Triglyceride

+

Methacrylated Fatty Acid

(Styrene Substitute)

O O OH O O

Low styrene content Thermal Cure Low VOC composite

O O O OH CH3 CH3 O O OH CH3 CH3 O O O OH n

Bimodal blends and other chemically modifications

O O O OH CH3 CH3 O O OH CH3 CH3 O O O OH n O O O OH CH3 CH3 O O OH CH3 CH3 O O O OH n O O O OH CH3 CH3 O O OH CH3 CH3 O O O OH n

Bimodal blends and other chemically modifications Soybeans

Triglyceride Triglyceride

+

Methacrylated Fatty Acid

(Styrene Substitute)

O O OH O O

Low styrene content Thermal Cure

69

Next Generation of Renewable Monomers

• Bisphenol A (BPA) is

ubiquitous monomer in the resins industry

• Endocrine disruptor
• Hypothesis: Isosorbide,

furans, and other renewable chemicals have the potential to replace BPA in all high performing polymers

• Difunctional
• Unique ring structures

BPA

Vanillin Isosorbide BHMF

Diamines

• 1. Epoxy curing

agents

• 2. Diisocynates for

polyurethanes

• 3. Polyimide

resins

Diols

• 1. Unsaturated

Polyesters

• 2. Polycarbonates
• 3. Polyols for

polyurethanes

Vinyl ester resins Novolac resins Epoxy resins

Cellulose Lignin

70

OH

Isosorbide Methacrylate - Viscosity

• Extremely low viscosity
• Viscosity: ~150 cP @ 25 °C
• Commercial VE: 48000 cP @ 25 °C
• Viscosity effect
• Low MW cross-linker

○ IM = 286 g/mol ○ VE = 540 g/mol ○ h ~ M

• H-bonding not a factor in IM

resin

Sadler, J.M. et al. Journal of Materials Chemistry A, (2013) 1, 12579-12586

147 5 295 50 100 150 200 250 300 350 IM IM/Styrene (65/35) Commercial VE/Styrene (65/35) Viscosity (cP) Sample

71

Isosorbide Methacrylate Polymers

• Isosorbide based VE
• Thermomechanical

properties

○ Tg > 250 °C ○ Storage Moduli = 3.1 GPa at 25 °C

• Extent of cure: 85.1 ± 1.3%
• Thermal stability

○ IDT = 305 °C ○ Tmax = 433 °C

• Flory-Fox equation
• Calculated IM Tg = 376 ± 5

°C

• Calculated commercial VE

Tg = ~200°C

0.02 0.04 0.06 0.08 0.1 0.12 0.1 1 10 100 1000 10000 100 200 300 400

Tan δ Modulus (MPa) Temperature (°C)

DMA Analysis

Storage Modulus (MPa) Loss Modulus (MPa) Tan Delta 255°C

2 2 1 1 sin) (

1

g g re g

T w T w T + =

Sadler, J.M. et al. Journal of Materials Chemistry A, (2013) 1, 12579-12586.

72

Furyl Epoxides

O O O O O BOF O O O O BOB

H2N NH2

PACM

S O O O O

BOT

< <

69oC 55oC 81oC

DGEPP

O O O O BOB >> 168°C 55°C

Methylene linkage on phenyl unit decreases Tg Hydrogen bonding and lack of symmetry increase Tg of BOF and BOT vs. BOB

O O O O

73

Bio-Based BPA Analogues

• Multistep

reaction

• Formation of

hydroxymethyl is the limiting step

• Bio-based

materials already possess reactive site

Bisguaiacol-F (BGF)

Vanillyl Alcohol Guaiacol

Bisphenol Alternative Derived From Renewable Substituted Phenolics, US Patent Pending; Provisional 2014

Novolac Resins Bisphenol Derivatives Furfuryl alcohol Vanillyl Alcohol

74

Toxicity Modeling

• Estimated using

EPISuiteTM software

• BGF shows

significant decreases in toxicity

75

Proposed Mechanism for Reduced Toxicity

• Substituents around aromatic ring should prevent or

limit recognition

• BGF vinyl ester resins have shown Tg's (186 °C)

similar to that of BPA based VE resins

76

Amine Curing Agents with Reduced Toxicity

• PMR-15 for high temperature composites applications uses

methylene dianiline (MDA)

• MDA is toxic
• Chemistry to prepare alternative amines

O O H2N NH2

RO O OR NH2 NH2

O O NH2 H2N R2 R1 O OH H O OM Me e

3 3 s st te ep ps s c cr re eo

• s

so

• l

l

N NH H2

2

M Me eO O N NH H2

2

O OM Me e

2 2

77

Summary and Conclusions

• Plant oil-based resins can be used to reduce

emissions, but do diminish thermal performance

• Lignocellulosic-based resins can have much

greater thermal and mechanical properties and have application to a variety of high performance polymers

• Renewable resins and polymers can be used

to reduce environmental and toxicity issues

• Renewable polymers have demonstrated

success in lab, field and commercial industry

78

SERDP & ESTCP Webinar Series For additional information, please visit: https://www.serdp-estcp.org/Program- Areas/Weapons-Systems-and- Platforms/(list)/1/

Speaker Contact Information john.j.lascala.civ@mail.mil, 410-306-0687

SERDP & ESTCP Webinar Series

Q&A Session 3

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