Several recipes are described for the preparation of porous polymeric monoliths in the capillary format, using poly(ethylene glycol) (PEG) as porogen as well as constituent in the monomer mixture. Acrylic or methacrylic monomers with a variety of terminal groups, with and without ethylene glycol links of differing lengths in the side chains, have been used in combination with triethylene glycol dimethacrylate (TEGDMA) and trimethylol-propane trimethacrylate (TRIM) as cross-linkers. PEGs of 4–20 kDa molecular weight dissolved in 2-methoxy-ethanol were used as porogens to yield large, biocompatible pores. A number of common solvents have been used as co-porogens for the PEGs, and the surface areas, median pore diameters, and back pressures of the resulting monoliths have been correlated with a number of molecular descriptors by means of chemometrics to describe the results. Photopolymerizations induced by either continuous or pulsed UV light were furthermore compared. Pore size distribution and surface area characterization have been assessed by nitrogen adsorption–desorption and mercury intrusion porosimetry, and scanning electron microscopy (SEM) was used to evaluate the differences in macroporous morphology obtained with the different porogen solutions. Mixtures selected from screening syntheses carried out in vials have been implemented in 100 μm fused silica capillaries and the back pressures measured and cross-validated with the pore information. Some of these capillary columns were finally tested for the separation of proteins using micro-HPLC. A series of new 3- and 4-ring bis(2-aminophenoxy) aromatic diamines were prepared. These, and corresponding, conventional bis(4-aminophenoxy) diamines were reacted with several aromatic bis(ether anhydride)s to form poly(ether imide)s. The diamines with 4-aminophenoxy groups gave high-molecular-weight polymers that were cast into films with good mechanical properties. In contrast, in almost all cases, diamines with 2-aminophenoxy groups only gave low-molecular-weight powdery products that could not be cast into coherent films. The low-molecular-weight products, prepared from stoichiometrically equal amounts of monomers, were examined by mass spectrometry and shown, in most cases, to consist primarily of cyclic oligomers; traces of linear oligomers were identified in some samples. Apart from a polyimide prepared from pyromellitic dianhydride and 4,4′-bis(2″-aminophenoxy)biphenyl, the only products found to contain significant proportions of linear oligomers were those prepared with a stoichiometric imbalance of monomers. End groups of the various linear oligomers were identified. The 2-aminophenoxy groups predispose the oligomers to cyclize as amic acids, and to remain as cyclics on imidization. In some cases [1+1] cyclic oligomers were observed although the most common species were the [2+2] cyclic dimers.