Needle-like polyanilines were prepared in aqueous media by chemical oxidation. p-Toluenesulfonic acid (pTSA) was used to protonate aniline (ANi) and readily made the anilinium complex. By slowly adding ammonium peroxydisulfate (APS) at 158C, polyanilines were prepared in the micelles and grew to be needle-like aggregates potentially useful as conductive fillers for electromagnetic interference shielding and radarabsorbing materials. The needle-like aggregates of protonated polyaniline prepared at 158C and 0.5 M aniline concentration with 3 h of APS addition time showed conductivity up to 3 S/cm and a maximum aspect ratio of 26 L/D. They were observed by scanning electron microscopy to peel off partially into fibrils after washing. The needle-like polyaniline-pTSA complexes prepared with 0.5 M aniline concentration showed good thermal stability up to 2008C. The high conductivity of the needle-like aggregates was ascribed to their well-developed crystalline structures, compared with those of spherical particles. J. VINYL ADDIT. TECHNOL.

Cellular phone housings were ground to make original particulates using a knife mill. Foams and adhesives with a lighter density than water were removed from ground mixtures using a sink-float process in water; ground metals, button rubbers, and wires were separated from desired materials by using a sink float process in salt All housing materials, consisting of seven thermoplastics included in cellular phone housings, showed better tensile properties than pure housing materials made of polycarbonate/acrylonitrile butadiene styrene, but they only had about half of the impact strength. In contrast, the low impact strength for all housing materials was improved by adding 25 wt % polyethylene elastomer and/or 2.4 wt % ground epoxy circuit boards for batch mixing. Impact strengths, tensile strengths, and the energy absorption ability of all housing materials were improved by adding 5.4wt% glycidyl methacrylate for twin screw extrusion.

Front covers of Motorola cellular phones, ground by a knife mill, contain 15.2 wt% metals, 1.9 wt% foams, 1.4 wt% rubbers, and 81.4 wt% thermoplastics with polycarbonate=acrylonitrile-butadiene-styrene blends. Separation of the thermoplastic scraps was performed using sink-float processes in water and salt solutions and electrostatic processes such as free-fall methods and roll separations. Impact modification of all housing containing six thermoplastic parts was carried out by the addition of a polyolefin elastomer. Unprinted and printed glass fiber-reinforced epoxy circuit boards were finely pulverized using a knife mill and a hammer mill. Ground printed circuit boards, separated by a roll separator, were compounded with desired thermoplastic mixtures. Izod impact strengths at various temperatures, tensile tests, scanning electron microscopy on fracture surfaces, and dynamic mechanical spectroscopy were performed to characterize the alloys and mixtures compounded by a batch mixer and twin screw extruder. Impact strength of the pure housing materials was almost twice higher than that of all housing materials compounded by the batch mixer. The polymer alloys compounded by the twin screw extruder showed lower impact strengths but higher tensile properties than those by the batch mixer because of the break-up of the interfacial instability.

This work focuses on the development of a new type of surface-relief grating (SRG) using more effective materials than a typical epoxy-based azopolymer for the recording layer of optical data storage. Thus, aniline-based azopolymers were synthesized by reaction of N,N-diglycidylaniline with aniline (An) followed by diazocoupling with 4-aminobenzonitrile or 4-nitroaniline. Such azopolymers when spin-cast from THF/dioxane showed better diffraction efficiency than those cast from THF alone due to residual dioxane creating a large free volume in the solid state. A second diazocoupling reaction of the diazopolymers initially obtained produced polymers with bis(diazobenzene) substituents which exhibited a higher saturation level of the diffraction efficiency for a thicker than for a thinner film. Azopolymers in which the diazo substituents incorporated hydroxyl groups ortho to the diazo unit were obtained via the reaction of the diglycidyl ether of bisphenol-A with aniline or 3-hydroxyaniline followed by coupling with diazotised hydroxynitroaminobenzene. These hydroxy groups, presumably as a result of their H-bonding to the diazo-N, effectively prevented the photoisomerization of the chromophores, so that the polymers showed no SRG at a normal laser intensity of 100 mW/cm 2 . Polyurethane-based azopolymers, synthesized with toluene-2,4-diisocyanate and disperse orange 17 containing no hydroxyl groups in the main chains, showed better diffraction efficiency than the other azopolymers with nitro group substituents.