Table 4 Parameters for determining the... | Emerald Publishing

Table 4

Parameters for determining the stability and the printability of a dispersion

Parameter	Instrument	Principle	Target range
*Stability behavior*
Particle size distribution q_r/particle size d	Laser diffractometer/syringe filter	Laser diffraction analysis/filtering method	d_max < (0.01−0.05 d_jet) (Derby and Reis, 2003) d_max < (0.02−0.05 d_jet) (Guo et al., 2017)
Zeta potential ζ	Zetasizer	Laser Doppler anemometry	ζ > +30 mV ∪ ζ < −30 mV (Greenwood, 2003; van Guyen et al., 2011), ζ > +15 mV ∪ ζ < −15 mV (White et al., 2007)
Zero shear viscosity η₀	Rotational rheometer	Rotation test	Standard value: 100–500 Pa⋅s (Wang et al., 1998) (predominantly depends on the particle volume fractions)
Storage modulus G’, loss modulus G”, loss factor δ	Rotational rheometer	Oscillation test	G” < G’ 0° < δ < 45°
Sedimentation behavior	Sedimentation test	Gray value analysis	Gray value change over time as small as possible
*Printability*
Viscosity in the flow area	Rotational rheometer	Rotation test	η₀ at ${\dot{γ}}_{0}$ → $η_{jet}$ at ${\dot{γ}}_{jet}$
Limiting high-shear viscosity	Capillary rheometer, rotational rheometer	Single-point measurement, extrapolation of the empirically obtained viscosity values in the flow area	$η_{jet}$ at ${\dot{γ}}_{jet}$ (specified by the printhead system)
Fluid dynamic numbers	–	–	Table 5
Relaxation behavior	Rotational rheometer	Stress relaxation test	< 10^–6ms (Hoath, 2016)
Wetting behavior	Drop shape analyzer	Contact angle measurement	0° < θ < 90°

Parameter	Instrument	Principle	Target range
Stability behavior
Particle size distribution q_r/particle size d	Laser diffractometer/syringe filter	Laser diffraction analysis/filtering method	d_max < (0.01−0.05 d_jet) (Derby and Reis, 2003)d_max < (0.02−0.05 d_jet) (Guo et al., 2017)
Zeta potential ζ	Zetasizer	Laser Doppler anemometry	ζ > +30 mV ∪ ζ < −30 mV (Greenwood, 2003; van Guyen et al., 2011), ζ > +15 mV ∪ ζ < −15 mV (White et al., 2007)
Zero shear viscosity η₀	Rotational rheometer	Rotation test	Standard value: 100–500 Pa⋅s (Wang et al., 1998) (predominantly depends on the particle volume fractions)
Storage modulus G’, loss modulus G”, loss factor δ	Rotational rheometer	Oscillation test	G” < G’0° < δ < 45°
Sedimentation behavior	Sedimentation test	Gray value analysis	Gray value change over time as small as possible
Printability
Viscosity in the flow area	Rotational rheometer	Rotation test	η₀ at ${\dot{γ}}_{0}$ → $η_{jet}$ at ${\dot{γ}}_{jet}$
Limiting high-shear viscosity	Capillary rheometer, rotational rheometer	Single-point measurement, extrapolation of the empirically obtained viscosity values in the flow area	$η_{jet}$ at ${\dot{γ}}_{jet}$ (specified by the printhead system)
Fluid dynamic numbers	–	–	Table 5
Relaxation behavior	Rotational rheometer	Stress relaxation test	< 10^–6ms (Hoath, 2016)
Wetting behavior	Drop shape analyzer	Contact angle measurement	0° < θ < 90°