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The model with competing exchange J and dipole-dipole D interactions on 2D hexagonal lattice is studied using Monte Carlo method. We calculate the energy, specific heat, order parameter, and susceptibility of the system close to the phase transition point Tc from stripe phase to isotropic stripe phase. This allows us to determine phase transition points for different values of exchange and dipole-dipole interaction ratio η = J/D and calculate the phase diagram for transitions to stripe phases AFh of different stripe width h. By using histogram method we determine the order of the transition at Tc. The first order phase transition was found to AF1 and AF2 phases and the second order one to AF3 and AF4 phases, with tricritical point being close to the AF2 and AF3 phase boundary in the phase diagram. We also calculate the structure factor above and below Tcs to AF1, AF2, AF3, and AF4 phases. Studying the dynamical properties of the model we have found that in AF1 phase and in a part of AF2 phase the spin relaxation corresponds to the Ising model dynamics. In phases AF3 and AF4 the dynamics slows down, and stripe domain growth with time is proportional to log t. With further increase of parameter η and approaching the ferromagnetic phase the dynamics satisfies the Ising model dynamics again.

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We obtained the phase diagram for the Ising model with competing exchange and dipolar interactions on 2D hexagonal lattice. By using histogram method we determined the order of the phase transition from isotropic stripe phase to low-temperature anisotropic stripe phases AFh of different stripe widths h. The first order phase transition was found to AF1 and AF2 phases and the second order -to AF3 and AF4 phases. We have also found that in AF1 phase stripe domain grows with time as t 0.5 . In phases AF3 and AF4 stripe domain growth is proportional to log t.