We have designed and synthesized rod-coil-rod triblock copolymers of controlled molecular weight by two-step nitroxide-mediated radical polymerization, where the rod part consists of "mesogen-jacketed liquid crystalline polymer" (MJLCP). The MJLCP segment examined in our studies is poly(2,5-bis[(4-methoxy-phenyl)oxycarbonyl]styrene) (MPCS) while the coil part is polyisoprene (PI). Characterization of the triblock copolymers by GPC, H-1 and C-13 NMR spectroscopies, TGA, DSC confirmed that the triblock copolymers were comprised of microphase-separated low T-g amorphous PI and high T-g PMPCS blocks. Analysis of POM and 1D, 2D-WAXD demonstrated that the triblock copolymers formed nematic liquid crystal phase. Morphological studies using TEM indicated the sample formed lamellar structure. (c) 2007 Wiley Periodicals, Inc.