Table 1.

Various mechanical dispersion processes.

entry	process	description	advantages	disadvantages	ref.
1	sonication (tip and bath)	The energy of high frequency sound waves is used to agitate the particles in a solution.	Equipment is inexpensive, processing is simple.	not suitable for high viscosity liquids; shortening of the filler; causes surface defects	[40]
2	calendering	A three-roll mill (3RM) uses shear forces produced in the roll gap to disperse, mix, or homogenize the viscous materials.	viscous materials can be dealt with, suitable for thermoplastic polymers	Individual nano-fillers cannot be used.	[53]
3	ball milling	The grinding action of a ball mill can unbundle the filler agglomerates.	Certain chemicals can be used for improved performance and to introduce various functional groups onto the filler.	MLG and CNT may be damaged.	[54]
4	high-shear mixing (HSM) and extrusion	HSM in general is a common dispersion technique and can be used to disperse MLG and CNT as well. Extrusion uses shear flow created by twin screws rotating at high speed.	The dispersion of fibers can be improved by high-shear mixing, and a high content of MLG and CNTs can successfully be uniformly dispersed by using this technique.	Extrusion is primarily suitable for solid materials.	[55]