Q2. What is the common technique for synthesising larger size graphene?
Chemical vapour deposition is the most commonly used technique for synthesising larger size graphene, but it results in polycrystalline structure.
Q3. Why is graphene emerging as a potential candidate for the reinforcement of nanocomposites?
Due to exceptional mechanical, thermal and electrical properties, graphene is emerging as a potential candidate for the reinforcement of nanocomposites [3-5].
Q4. What is the effect of mis-orientation angle on graphene?
Higher mis-orientation angle configurations lead to redistribution of stress uniformly throughout the bi-crystalline graphene sheet that maximizes the load transfer phenomenon and helps in improving the tensile strength.
Q5. What is the reason for the high tensile strength of graphene?
It is predicted from the post processing of dump files that higher mis-orientation angle configurations contain more energetic sites (due to high density of dislocations) relative to lower mis-orientation angles for a given weight percentage of graphene in PE; therefore, there would be more wrinkling in higher mis-orientation angles and thus high tensile strength.
Q6. What are the main mechanisms causing an increase in the tensile strength of bi-?
The authors also perceived that wrinkling with substantial out-of-plane deformation in bi-crystalline graphene containing higher mis-orientation angle GB resulted in more number of adhesion points and better non-bonding interaction at the interface; which were the main mechanisms causing an increment in the tensile strength.
Q7. What are the limitations of graphene synthesis?
Due to limitations associated with the synthesising techniques, nanomaterials e.g. large size graphene nanosheets are synthesised with geometrical defects such as vacancies, dislocations and grain boundaries (GB) [34, 35].
Q8. What is the effect of graphene on the mechanical properties of polymer composites?
Liu et al. [33] concluded in their work that grafting of graphene with polymer chains helps in improving the shear strength as well as graphene’s dispersion in the polymer matrix.
Q9. What is the effect of the tensile strength of graphene on the GB?
Snapshots showing crazing and voids formation in PE when subjected to tensile loadAfter predicting tensile strength of nanocomposites, next set of simulations were performed to investigate the shear strength of the interface between graphene and PE matrix.
Q10. What is the effect of the curved graphene on the tensile strength?
better interfacial properties have been predicted from the interaction energy trend for bi-crystalline graphene nanocomposites as compared to pristine graphene.
Q11. How was the graphene pulled out of the PE matrix?
In order to capture the shear strength at the interface, simulations were performed with periodic boundary conditions imposed only in two principal directions, whereas the third principal direction was used to pull the graphene out of polymer matrix as illustrated in Fig.7.
Q12. What is the effect of a curved graphene matrix on the tensile?
It was also predicted from the tensile deformation of above designed nanocomposites that after achieving the maximum tensile strength, permanent deformation in the form of voids and crazing starts generating in PE matrix as shown in Fig.6.
Q13. What is the resulting shear force on graphene nanosheets?
In the graphene reinforced PE system, the pristine and bi-crystalline graphene nanosheets were pulled out of the PE matrix with a velocity of 0.0001 Å/fs along x-direction (non-periodic) and the resulting shear force on the graphene nanosheets in the pullout direction was plotted in Fig.8.
Q14. What is the effect of the stress-strain response of graphene reinforced nanocompo?
Due to increased interaction, atoms configuring GB atoms were actually pulled by the PE chains that results in inducing wrinkles (crests and troughs) in the 2D bi-crystalline graphene; in contrast, the pristine graphene structure in PE/GRP nanocomposite relatively remained flattened (minimal out of plane displacement) during tensile deformation as captured in Fig.5.
Q15. What is the effect of the stress-strain responses on graphene?
It can also be inferred from the stress-strain responses plotted in Fig.3 and Fig.4 that increment in tensile strength of nanocomposites is more prominent in bi-crystalline graphene containing higher mis-orientation angles.
Q16. What is the way to prove that bi-crystalline graphene is a superior reinforcement?
All the simulations help in concluding that bi-crystalline graphene is a superior reinforcement for developing the future nanocomposites as compared to pristine PE nanocomposites.