Nonionic water‐soluble polymeric surfactants have been prepared by addition of long‐chain n‐alkyl epoxides to nonionic cellulose ethers. The polymers exhibit properties which can be explained by interchain association. The relationship between hydrocarbon‐modifier carbon number and the onset of association follows a linear relation analogous to those observed for monomeric nonionic surfactants.

The preparation and properties of highly crystalline ionomers formed by the copolymerization of propylene and low levels of ethylcholoroaluminium 10‐undecenoate have been investigated. Few of the variables studied had dramatic effects on the copolymerization. Thus, a five‐fold increase in undecenoate concentration gave only about a 20% increase in acid incorporation into the copolymer. Increasing temperature resulted in increased acid content, but handling problems in a I gal stirred reactor limited polymerization of 80°C. Rates were lowered in the presence of complex, but the effect was minimized by hydrogen. Rheological measurements showed an increase in low shear melt viscosity of the pottasium salts by up two orders of magnitude relative to the acid from. Ionomers containing two or more carboxyl groups as their potassium salts, and having a broad molecular weight distribution, had an extended rubbery plateau range, covering most of the shear ranges of normal processing. The zero‐shear activation energy for viscous flow was 42 kcal, comparable to ABS and polystyrene. These ionomers are promising candidates for thermoforming applications

The effect of uniaxial orientation on the free‐volume and oxygen‐transport properties of a propylene copolymer with 4.5 wt % ethylene was examined. The free‐volume hole size and hole density were measured with positron annihilation lifetime spectroscopy. Subsequently, the free‐volume characteristics were correlated with the oxygen‐transport properties. Orientation had only a small effect on the total amount of free volume: a small increase in the hole density was offset by a small decrease in the hole size. As a result, the oxygen solubility and amorphous‐phase density were unchanged by orientation. However, a pronounced decrease in the oxygen diffusivity when the draw ratio exceeded 6 indicated a change in the dynamic free volume. This was attributed to an increasing number of taut tie chains, which retarded oxygen diffusion. The reduced amorphous chain mobility was also manifest in the increased glass‐transition temperature, decreased bulk thermal expansivity, and decreased expansivity of free‐volume holes. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1230–1243, 2005

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