Answer

They both are shoots they are presumed as modified branches or leaf like branches. In modified plants like in cactus leaf is get modified into spines to reduce the transpiration.

phylloclade is modified stem and it carries out the function of leaf. The term phyllo is stands for leaf and Cladode resembles as a leaf. the difference is only that phylloclade is having succession of nodes and internodes atomg short intervals but cladode have rarely two internodes. In short phylloclade is the subset of cladodoes.