The transport properties of an AB random copolymer melt near the order-disorder phase transition are examined by using a mode coupling approach. The key parameters of the model are the volume fraction of type A monomers, f, the Flory χ parameter, and a parametert λ that characterizes the monomer sequence distribution. The equilibrium phase diagram for this model of random copolymers contains a Lifshitz point at λ = λL. For λ < λL, composition fluctuations first become unstable at finite wavelength and the homogeneous phase seperates into microphases, while for λ >λL the fluctuations first become unstable at infinite wavelength giving a binary fluid type transition. Our analysis shows that for λ < λL the Onsager coefficient remains finite as the phase transition is approached, while the viscosity diverges proportional to ϵ−32, where ϵ = (T − Tc)/Tc is the dimensionless difference between the temperature and the critical temperature. For λ >λL, there is a very weak divergence in the viscosity, but the Onsager coefficient diverges proportional to ϵ−12 for ϵ−(λ - λL) å 1, and proportional to ϵ−34 for ϵ−(λ - λL) « 1. The dependence of the Onsager coefficient and viscosity on χ, f and λ are explicitly determined.
