A series of novel stable polyurethane emulsions with high-solidcontent and low-viscosity were prepared by self-emulsification.They were prepared by the reaction of poly(tetrahydrofuran-co-propylene oxide) glycol(Ng210)

isophorone isocyanate（IPDI） with sodium 1

2-dihydroxy-3-propanesulfonate（DHPS） and dimethylolpropanoic acid (DMPA) as hydrophilic chain-extending agents.Influence of the mass ratio of DHPS and DMPA on properties of polyurethane emulsions and films was analyzed.The results showed that the obtained emulsions had multi-modal distribution in particle size

and the particles were spherical in shape.It was noticed that with increasing proportion mass ratio of DHPS and DMPA

the average particles diameter of polyurethane emulsion became smaller and poly-dispersion became wider.In addtion

when the mass ratio of DHPS and DMPA ranges from 4:10 to 6:10

the particle size ratio of big particles and small particle ranges from 6 to 8

the solid-concent of emulsion reaches above 70%

and the volume fraction of big particle ranges from 75% to 80%.It is also noticed that the high-solid-content emulsions exhibit a pseudo-plastic behavior

the apparent viscosity is less than 250 mPa·s (shear rate is 25 s-1).The apparent viscosity of polyurethane emulsion increases with increasing proportion mass ratio of DHPS and DMPA

and the apparent viscosity of emulsion with different solid-content decreases with increasing the shear rate

that is

the emulsions show characteristics of shear thinning.Polyurethane emulsions are endowed lower surface tension which is 41.0～60.0 mN·m-1

and the stability of emulsion is good at high temperatures and low temperatures as well as in storage.When compared to traditional polyurethane emulsions

the emulsions with high-solid-content present films of better mechanical properties.