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Hyperbranched polyurethane (HPU) with a long chain between the branching points was synthesized from isocyanate end-capped polycarbonatediols and diethanolamine via an oligomeric A 2 + CB 2 approach. The effects of the temperature and molar ratio of nPCDL/nNCO on the degree of branching (DB) were studied. The structure of the products was characterized by 13 C-NMR. The results showed that the polymers had a hyperbranched structure and the DB value was 0.75 when the nPCDL/nTDI was 0.5 at 55 • C. The thermal and adhesive properties were investigated by thermogravimetric analysis and tensile test, respectively. The HPUs could be used as hot melt adhesive, and the maximum lap shear strength was up to 6.5 MPa. Moreover, the effects of the length of the chain, reaction temperature and reaction time on the adhesive ability were investigated.

A series of highly branched waterborne poly(urethane-urea)s (HBWPUs) containing pendant carboxylate anion as the hydrophilic groups were prepared via A 2 þ B 3 approach using isocyanate end-capped polycarbonatediols as an A 2 oligomeric monomer and triamine as a B 3 monomer. The structure of the products were characterized by FTIR and 13 C-NMR. The particle size, solution viscosity, thermal and mechanical properties were measured by photon correlation spectroscopy (PCS), rotational rheometer, differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), dynamic mechanical analysis (DMA) and tensile tests, respectively. It was found that the particles size mainly depended on the molar ratio of nNCO/nOH and the content of hydrophilic groups; the HBWPUs showed lower viscosity but higher T g compared with linear waterborne polyurethane. The tensile testing, DMA measurements and rehological measurements revealed that the molar ratio of [B 3