Polyarylene ether nitriles (PENs)/TiO2 nanocomposite has been successfully synthesized through the sol–gel process; the films were characterized by FTIR, XPS, SEM and TG. The dielectric properties of the films were also measured to find that the dielectric constant of nanocomposite films increases linearly with the TiO2 weight content and reaches 6.21 at a 20 wt.% TiO2 content. The nanocomposite films have favorable mechanical and thermal properties and are not sacrificing dielectric breakdown strength compared to that of pristine polymer. © 2004 Elsevier B.V. All rights reserved.

A new kind of aliphatic polyetheresteramide copolymers (PEEAs) based on E-caprolactone, 11-aminoundecanoic acid, and poly (ethylene glycol) (PEG) were synthesized by melt polycondensation. The thermal and hydrolytic degradation behaviour of these copolymers was studied using FTIR, 1H-NMR, and TGA. PEG content, thickness of the test sample, and pH of degradation medium have great effect on degradation rate. The degradation rate increased with PEG content and pH, but decreased with thickness of the test sample.

Factors influencing the in vitro release of bovine serum albumin (BSA) from poly(butylcyanoacrylate) (PBCA) nanocapsules, such as the pH value, BSA loading, the polymeric nanocapsule walls and protein molecular weight, were investigated in detail. The BSA release rate was affected by the degradation rate of the polymeric wall and protein loading. For low molecular weight proteins, the initial burst release was faster than that of high molecular weigh proteins and got to equilibrium quickly. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis results showed that BSA encapsulated within PBCA nanocapsules did not suffer covalent aggregation or fragmentation during the initial days of in vitro incubation. For nanocapsules prepared by interfacial polymerization in waterinoil microemulsions, these findings were useful as a foundation for the development of nanocapsules with desired properties.

In this work, a new kind of aliphatic polyesteramide (PEA) copolymer based on €-caprolactone and 6-aminocaproic acid was synthesized by the melt polycondensation method. Biodegradable PEA fibers were processed by the meltspinning method. 1H-NMR, FTIR, SEM, and tensile testing were used to characterize the degradation of PEA fibers in concentrated alkaline solution. The PEA fiber undergoes surface erosion in such concentrated alkaline solutions.