negatively charged sheaths around the globule prevents them from coming together and  forming aggregates.  what does this statement means????

 ( NCERT lines page:137)

These negatively charged sheath of the soap around the dust particles are separated from eachother in water and do not get aggregated because the hydrophobic part of the soap is in the dust particle and hydrophillic part projects out of the dust particle and this part get bonded with water and do not get aggregated. This form many dust + soap globules in water separatly.