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Synthesis and characterization of titanium and zirconium oxide and carbide thin films (1–25 μm) on spherical substrates is reported. Hydrolysis of an appropriate metal alkoxide precursor in aqueous acid yields the amorphous metal oxide coating. Thermal treatment can produce the highly crystalline phases of the oxides or, in the presence of a carbon containing reducing gas, the metal carbide. Scanning electron microscopy and x-ray diffraction have been used to study the surface morphology and the crystallographic structure of the coating films. Morphological characteristics strongly depend on the acid species and acid strength used during hydrolysis. The thickness of the film is also governed by control of the acid hydrolysis step.

Poly(Vinyl chloride) is the basic material for a huge number of products which are fabricated using very many different techniques. Established processing techniques continue to be improved, leading to additional benefits in process efficiency and product quality. New processes are also being introduced which are intended to increase the efficiency of material usage and to open up new application areas. These include: molecular orientation, foaming, and cross-linking. Developments are also occurring in the use of PVC in conjunction with other materials as micro- or macro-composites. Processing techniques include coextrusion and lamination. Many processing methods are likely to benefit from the microelectronics revolution in process control and monitoring.