Nonionic alkyl ethoxylates (C(n)E(m)) have been extensively studied for their adsorption, aggregation, and solubilization individually and in small groups. In this work, we report a more systematic study of the effects of alkyl chain (tail) and ethoxylate (head) length on the size, shape, and extent of intermixing within the C(n)E(m) micelles in aqueous solution. Data from small angle neutron scattering (SANS) and nuclear magnetic resonance (NMR) were combined to undertake the structural characterization of micelles formed from the two separate series of surfactants C(n)E6 (n = 10, 12, 14) and C12E(m) (m = 5, 6, 8, 10, 12). The micellar core volume (V(core)) could be well determined with reasonable accuracy and linked to the hydrophilic-lipophilic balance (HLB) of the surfactant, with a sharp size and shape transition occurring around HLB = 12.5. NOESY NMR results revealed protrusions of the terminal methylene groups into the ethoxylate shell, thus providing direct experimental evidence for the phenomenon of "roughness" or intermixing of the core-shell interface. These detailed studies are compared with previous investigations on this model surfactant system.

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Hybrid sol-gel inorganic-organic fibres offer great potential in tissue engineering and regenerative medicine. A significant challenge is to process them using scalable technologies into useful scaffolds that provide control over fibre diameter, morphology, mechanical properties, ion release, degradation and cell response. In this work we develop formulations that are amenable to processing via solution blow spinning (SBS), a rapid technique using simple equipment to spray nano-/ micro-fibres without any electric fields. The technique is extended to produce porous class I and II hybrid fibres using cryogenic SBS, with formulations developed based on tetraethyl orthosilicate/gelatin that are relatively facile to lyophilise. The formulations developed here take advantage of the reversible thermally activated conformation change of gelatin in aqueous solutions from random coil to triple helix to enable viscosity tuning and therefore fibre spinning. Gelatin is functionalised with (3-glycidyloxypropyl)trimethoxysilane to produce class II hybrids which exhibit controllable time-and temperature-dependent viscosity profiles which can be tuned for spinning into highly porous fibres.Ryan D. Greenhalgh and William S. Ambler are joint first authors due to equal contribution.

Zeolite MAP (maximum aluminum P) is a zeolite of the gismondine family that has recently found utility as an ion exchanger for water softening in detergents applications. It is composed of spherical agglomerates of small crystallites which have appreciable external surface area. A combination of 27Al and 29Si single-pulse and cross-polarization MAS NMR experiments have been used to elucidate the nature of the surface of zeolite MAP. The 29Si experiments given an external surface area of approximately 8% of the total, which is consistent with that expected based the calculated particle size. The T cp is similar to amorphous aluminosilicates while the T 1 ρ values are significantly different, indicating protons with a different type of mobility. The 1H NMR is consistent with the silanols being located on the external surface of the crystallites.

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