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Following a prepolymer mixing process, polyurethane (PU) anionomer dispersions were prepared from polyethylene adipate glycol (PEA), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI) and dimethylol propionic acid (DMPA) as a potential ionic centre. E †ects of prepolymer molecular weight, PEA molecular weight, hard segment content, DMPA content, degree of neutralization and mixed diisocyanates have been studied in terms of particle size and viscosity of emulsion, and surface, mechanical and dynamic mechanical properties of the emulsion-cast Ðlms. Particle size decreased and emulsion viscosity increased with increase in prepolymer molecular weight and PEA molecular weight, DMPA content, the degree of neutralization and IPDI content in mixed isocyanate systems. The decrease in particle size was due to increased chain Ñexibility and/or hydrophilicity of the PU. The mechanical and dynamic mechanical properties of the PU ionomer dispersions were interpreted in terms of soft segmentÈhard segment phase separations, hard segment content, chain Ñexibility and coulombic forces.

Following a prepolymer mixing process, polyurethane (PU) anionomer dispersions were prepared from polyethylene adipate glycol (PEA), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI) and dimethylol propionic acid (DMPA) as a potential ionic centre. E †ects of prepolymer molecular weight, PEA molecular weight, hard segment content, DMPA content, degree of neutralization and mixed diisocyanates have been studied in terms of particle size and viscosity of emulsion, and surface, mechanical and dynamic mechanical properties of the emulsion-cast Ðlms. Particle size decreased and emulsion viscosity increased with increase in prepolymer molecular weight and PEA molecular weight, DMPA content, the degree of neutralization and IPDI content in mixed isocyanate systems. The decrease in particle size was due to increased chain Ñexibility and/or hydrophilicity of the PU. The mechanical and dynamic mechanical properties of the PU ionomer dispersions were interpreted in terms of soft segmentÈhard segment phase separations, hard segment content, chain Ñexibility and coulombic forces.

A series of Latex AB crosslinked polymers have been synthesized from polyurethane (PU) (polymer A) and polystyrene (PS) (polymer B). The effect of PU/PS composition, crosslinking density in the PS domain, as well as in PU has been studied in terms of dispersion size, TEM morphology, mechanical, dynamic mechanical properties, in addition to swellability in water and toluene of the dispersion cast film. An inverted core (PS)-shell (PU) morphology with very fine (tens of nanometers) dispersion was obtained, and the film properties were well controlled by the Latex composition and crosslinking density of both phases.