A series of blends containing phenylethynyl-terminated arylene ether (PETAE) oligomers and phenylethynyl-containing reactive diluents were prepared and characterized. Most of the blends prepared met the objective of this work which was to further modify the PETAE oligomers in order to improve solvent resistance, increase modulus and adhesive strength, and reduce melt viscosity. The cured blends generally have higher glass transition temperatures and improved mechanical properties compared with the analogous thermoplastic polymers.