Novel Malleable Covalent Networks and Their Applications in Repairable Carbon Fiber Reinforced Composites with Full Recyclability

Transcription

1 Novel Malleable Covalent Networks and Their Applications in Repairable Carbon Fiber Reinforced Composites with Full Recyclability Wei Zhang Department of Chemistry and Biochemistry Materials Science and Engineering Program University of Colorado, Boulder Global Automotive Lightweight Materials Conference August 23-25, 2016, Detroit

2 Macrocycles Cages Catalyst Development Imine metathesis Olefin metathesis Alkyne metathesis Polymer Acc. Chem. Res. 2014, 47, Chem. Soc. Rev. 2013, 42, 6634.

3 Engineering Polymers Thermoplastics Thermosets Linear polymers Remodable Recyclable Soluble in organic solvents Network polymers Permanent shape Not recyclable Insoluble

4 Malleable Thermosets Thermoplastics Thermosets Easy process High mechanical property Solvent compatibility Utilizing equilibrium between bond breaking and formation is the key!

5 Malleable Materials Based on Covalent Organic Networks Epoxy networks Zn(OAc) 2 required Relaxation: > 120 o C Science 2011, 334, 965. Polyene networks Ru catalyst required Relaxation: 25 o C J. Am. Chem. Soc. 2012, 134, Catalyst free, more practically useful operating temp?

6 Malleable Polyimine Stress-Relaxation Study Relaxation Modulus (MPa) Temperature increasing from 50 O C to O C Shift Factor 10 4 Experiment Simulation Temperature ( O C) Relaxation Modulus (MPa) Time (min) Stress-relaxation exhibits Arrhenius-like temp dependence Time (min)

7 Recycling of Polyimine from Powder to Coherent Solid Stress (MPa) st Generation 2 nd Generation 10 3 rd Generation 4 th Generation Strain (% elongation) Ø A slight decrease in elastic modulus Ø A slight increase in the tensile strength Ø High recyclability Taynton, P. et al. Adv. Mater. 2014, 26, 3938.

8 User-Friendly Processing, Easy Custom Fit

9 Transamination Reaction at Various Temperature (a) (b) 1 h 2 h 30 h 77 h Ratio of new imine/ parent imines [ab]/([aa]+[bb]) C C C C C C Heat is important, how about water? Time (h)

10 Insignificant Hydrolysis of the Polyimine in Water -imine -CHO Wet -imine -CHO Dry Imine/aldehyde: ~40/1 in wet polymer; ~ 60/1 in dry polymer 1.5% of imine linkages are hydrolyzed when the polymer is saturated with water

11 Water Driven Malleability 10 2 Relaxation Modulus (MPa) o C under water Time (min) More efficient relaxation under water than under heat

12 Heat or Water Driven Reprocessibility No catalyst, no organic solvent, a truly green process

13 Reshaping of Polyimine Using Only Water

14 Malleable Thermosets

15 Heat or Water Driven Malleability and Self-Healing in a Highly-Recyclable Covalent Network Polymer

16 Malleable Polyimine vs. Conventional Polymers Polymer Materials Young s Modulus (GPa) Tensile Strength (MPa) Processing Temp. ( o C) HDPE Polypropylene Polyimine Polystyrene Polycarbonate PET

17 Property Tunability via Structure Variation Taynton, P. et al. submitted.

18 Tensile Test of Polyimines

19 Mechanical and Thermal Properties of Polyimines Polyimines Tensile strength (MPa) Elastic modulus (GPa) Elongation at break (%) T g Nitrogen ( o C) b content c (mol%) Weight Gain 4N1 a N N NMe C C C C (%) Taynton, P. et al. submitted.

20 Moisture-induced Property Change Taynton, P. et al. submitted.

21 Hydrophobic Polyimine Water Resistant

22 Advantages of Solid-State Battery Introduction: Non-flammable electrolyte Stability at high temperatures High energy density Excellent cycling stability Replace liquid electrolyte with solid

23 Commercial Lithium Ion Battery < 40 C 75 C Pertubation Passivation Decompostion Thermal Runaway (Point of No Return) O 2 Heat LiPF 6 in organic solvents Li(Ni 1/3 Mn 1/3 Co 1/3 O 2 ) Graphite

24 Commercial Lithium Ion Battery < 40 C 75 C 130 C Pertubation Passivation Decompostion Thermal Runaway (Point of No Return) Cathode Decompostion O 2 Heat

25 < 40 C Commercial Lithium Commercial Li + Ion Battery battery 75 C 130 C Pertubation Passivation Decompostion Cathode Decompostion Ignition Thermal Runaway (Point of No Return)

26 Solid-State Li-ion Electrolyte Membrane Dry processing 64 um thick 80% active material loading Near theoretical density Whiteley, J. M. et al. Adv. Mater. 2015, 27, 6922.

27 Solid-State Li-ion Electrolyte Membrane Greater conductance Greater rate capacity High durability (> 200 cycles) Enhancement in both gravimetric and volumetric energy density! Whiteley, J. M. et al. Adv. Mater. 2015, 27, 6922.

28 Carbon Fiber Reinforced Composites (CFRCs)

29 Carbon Fiber Reinforced Polyimine Composites Carbon fiber CFRC c 2ply CFRCs e Easy process, no curing step, multilayer CFRCs in 1min, efficient production cycle Taynton, P. et al. Adv. Mater. 2016, 28, 2904.

30 Moldable and Weldable Taynton, P. et al. Adv. Mater. 2016, 28, 2904.

31 Repairable and Recyclable MPa Virgin polymer 10%recycled 33% recycled % elongation

32 Unique Properties of Polyimines and Their Composites Material Property Value Proposition (1) Heat-induced vitrification Eliminate curing Improved manufacturing economics Enables composite thermoforming Reduced manufacturing cycle time Remoldable Solvent free (2) Chemically reversible polymerization Closed-loop recyclable Reduced scrap

33 Acknowledgements Prof. Rich Noble (CU ChIE) Prof. Won Park (CU EE) Prof. Xuedong Liu (Biochem) Prof. Sehee Lee (CU ME) Prof. Jerry Qi (GaTech) Prof. Yang Qin (UNM) Dr. Sheng Dai (ORNL) Dr. Hai Long (NREL) Prof. Rich Shoemaker Prof. Dieter Schlüter (ETH) Dr. Yinghua (Alice) Jin Dr. Haishen Yang Dr. Ya Du Qi Wang Chenxi Zhang Ryan McCaffrey Kenji Okochi Philip Taynton Youlong Zhu Chao Yu Michael Ortiz Chengpu Zhu Yu Gong Guolong Lu Kun Xu Xinyu Hu Lili Tan Former group members: Prof. Jyothish Kuthanapillil Prof. Aibo Zhang Prof. Huagang Ni Prof. Dazhi Tan Athena Jin Ryan Denman Ian Aldridge Alice Hearn Devon Trahan Gun Su Han Sam Loob

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