Loop space formalism and renormalization group for the infrared asymptotics of QCD

General approach is developed to determine the infrared asymptotics of arbitrary hard process of perturbative QCD based on a systematic use of renormalization properties of contour averages. It is shown that the IR peculiarities of the process can be factorized out into the superposition of vacuum averages IR singularities of which are shown to be in a one-to-one correspondence with the UV ones. It is established that the renormalization group methods can be applied to study the infrared asymptotics of QCD. The anomalous dimension of the relevent RG equations is calculated up to 2 loops coinciding with the IR asymptotics of the quark propagator and quark form factor are obtained. The approach can be applied to study the infrared structure of the factorization procedure for hard QCD processes