(2R,3S)-2-Fluoro-3-methylpentyl 4’-[[11-(vinyloxy)undecanyl]oxy]biphenyl-4-carboxylate (15; 2R, 92% ee) and (2S,3S)-2-fluoro-3-methylpentyl 4’-[[11-(vinyloxy)undecanyl]oxy]biphenyl-4-carboxylate (16; 2S, 96% ee) diastereomers and their corresponding homopolymers and copolymers with well-defined molecular weights and narrow molecular weight distributions were synthesized and characterized. The phase behavior of the two diastereomeric polymers can be compared only by superimposing the dependence of their transition temperatures as a function of molecular weight. The phase behaviors of 15 and poly(l5) are identical to those of 16 and poly(16), respectively, except that the monomers show slightly different transition temperatures and enthalpy changes from each other. Both monomers display enantiotropic S-A, monotropic S-c*, and S-x (unidentified smectic) phases and a crystalline phase, while the corresponding polymers exhibit enantiotropic S-A, S-c*, and S-x mesophases. Phase diagrams were investigated in detail in binary mixtures of 15 with 16 and poly(15) with poly(16) and in binary copolymers of 15 with 16 as a function of the composition of the two diastereomeric structural units. In all these systems the two diastereomeric structural units derived from the two monomers are miscible and therefore isomorphic within all their mesophases and over the entire range of compositions. This is in contrast to the crystalline phases of the monomers whose phase diagram displays an eutectic composition. The S-A-I transition of the binary mixture of 15 with 16 is with 0.2-0.4 degrees C higher in the 50/50 mixture than the theoretical value expected for an ideal solution, demonstrating the presence of chiral molecular recognition between the two diastereomers in their S-A phase. In the polymer and copolymer systems chiral molecular recognition present in the monomers seems to be canceled or it is too small to be detected. On the contrary, the S-A-S-c* and S-c*-S-x transition temperatures show negative deviations from the theoretical ideal values in all systems, indicating the nonideal solution behavior of the two diastereomeric structural units in the S-c* and S-x phases.