We report on the structure and the viscoelastic properties of two side-chain liquid-crystalline polymers with different spacer length in the melt and fiber states and of their Copolymers with a semicrystalline block. Optical microscopy, X-ray scattering, and differential scanning calorimetry are employed for the structure investigation and rheology for the dynamics. The smectic and nematic liquid-crystalline polymers exhibit non-Newtonian low-frequency response and violate the empirical principle of time-temperature superposition with the effect being more pronounced in the former. Fibers drawn from the melt exhibit significantly different structure from the melt samples. In the diblock copolymer composed of smectic/crystalline blocks, the strong first-order isotropic-to-smectic transition induces the weak disorder-to-lamellar transition between the dissimilar blocks in the diblock.