A range of poly­(ethylene glycol) (PEG)-based polyacrylate networks with two different topological properties were synthesized by photoinitiated free-radical polymerization and analyzed by mechanical, chromatographic, and NMR methods. Comparison between networks with ziplike and pointlike junctions pinpointed the critical role of network topology in generating the so-called “short chain abnormality” in polymer dynamics. In particular, double quantum (DQ) NMR analysis of the ziplike networks identified strong topological constraints on isotropic movement of network chains directly resulting in increased effective functionality of the system. The failure of classical rubber elasticity theory in treating networks with ziplike cross-links is found to arise primarily from non-Gaussian behavior of these network chains caused by the topological constraints.

h i g h l i g h t s g r a p h i c a l a b s t r a c t Comprehensive 2D-LC was used to characterize polymeric nanoparticles.The relation between particle size and composition was determined.Applicable to hydrophobic, hydrophilic and charged monomercomprising particles. An algorithm was developed to automatically correct for HDC band broadening. Method can be used to study particle formation during emulsion polymerization.

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Water-borne polymers are in ever-increasing demand due to their favorable ecological profile compared to traditional solvent-borne polymer systems. Many water-borne polymer particles are stabilized in aqueous media by the incorporation of acid-functional monomers. Due to the large variety of comonomers applied, these water-borne polymers have various superimposed statistical distributions, which make it challenging to obtain in-depth information regarding incorporation of the acidic monomers. For selective analysis of the incorporated acidic monomers, a charge-based non-aqueous capillary electrophoresis (NACE) separation was developed. Two approaches were developed: (i) deprotonation of the acid functionality with an organically soluble strong base and (ii) heteroconjugation of anions of carboxylic acids with incorporated acid functionality. In both approaches, N-methylpyrrolidone, as a strong solvent for polymers with a favorable relative permittivity for the presence of dissociated ionic species, was used for the separation. It was shown that anions of carboxylic acids specifically associate with the incorporated acid groups in the polymers, resulting in negatively charged complexes that could be separated based on charge-to-size ratio by NACE. Although both approaches give comparable results with respect to acid distribution for acid-functional polymers, the effective mobility of the deprotonated polymers is roughly double that obtained from the heteroconjugation approach. Unlike the heteroconjugation approach, deprotonation conditions were detrimental to the fused-silica capillary, limiting practical use. Polymers with different chemical compositions, molecular weights, and acid contents were subjected to the CE approaches developed. Polymers with varying molecular weight but similar relative acid monomer content were shown to have similar migration times, which confirms that this approach separates polymers based on charge-to-size ratio.