Inflammogenic effect of polyacrylic acid in rat lung following intratracheal instillation

Table 1 Physiochemical characterization of the polymer used in the present study

Name	Polyacrylic acid	Structural formula
CAS number		9003-01-04
Bulk	Purity	≦ 100% (Benzene 0.5%)
	Molecular weight
	Weight average molecular weight (M_W)	6,490,000
	Viscosity average molecular weight (Mv)	3,000,000 (average)
	Cross-liking	~ 0.1%
	Appearance	Solid, white powdered
	Odor	None
Suspension	*Secondary particle diameter	3.00 µm (median), 2.31 µm (mode)
	Hydrodynamic diameter	1.62 µm (average)
	**Effective density	1.08 (with solvent)
	***Effective density	0.26 (without solvent)
Aerosol	Mass median aerodynamic diameter	0.92 µm
	****Effective density	1.43 g/mL

*Secondary particle diameter: the particle diameter of agglomerate. Mode diameter: the most frequent particle size
**The effective density (g/mL) (with solvent) ρ_{Eff_in dispersion with solv.}\(=\frac{({\rho }_{poly} {V}_{poly}) +({\rho }_{solv} {V}_{solv})}{V_{total}}\)
\(=\frac{\left(1.43 \times \frac{\pi }{6} {0.92}^{3}\right) + \left(1.00 \times \frac{\pi }{6} \left({1.62}^{3 }- {0.92}^{3}\right)\right)}{\frac{\pi }{6} {1.62}^{3}}\)
\(=\) 1.08 g/mL
here, ρ_{Eff in dispersion with solv.}: effective density in dispersion with solvent, ρ_poly: density of polymer (= effective density of polymer), ρ_solv: density of solvent (= density of water), V_poly: volume of polymer, V_solv: volume of solvent), V_total: volume of swelled polymer (= V_poly + V_solv).
***The effective density (g/mL) (without solvent)
ρ_{Eff_in dispersion without solv.} \(=\) \(\frac{Mass\, concentration \,({\rm mg}/{\rm mL})}{Volume \,concentration \,({\rm mL}/{\rm mL})}\)
\(=\) \(\frac{2.5}{9.52 \times {10}^{-3}}\)
\(=\) 0.26 g/mL
here, ρ_{Eff in dispersion without solv.}: effective density in dispersion without solvent
****The effective density (g/mL) (aerosol)
ρ_{Eff_aerosol} \(=\) \(\frac{Mass \,concentration \,({\rm g}/{\rm m}^{3})}{Volume \,concentration \,({\rm mL}/{\rm mL})}\)
\(=\frac{1.76 \times {10}^{-3} }{9. 52}\)
\(=\) 1.43 g/mL
here, ρ_{Eff aerosol.}: effective density of aerosol

ISSN: 1743-8977