Hydroxyapatite is a hydrated calcium phosphate. As such it dehydroxylates and decomposes upon exposure to elevated temperatures.
By Dr. Cameron Chai
13 Jun 2002
Cellulose acetate is derived from renewable resources such as wood pulp, which differs from most other man-made polymers which are petrochemical derivitives. General properties include transparency, glossiness, natural feel and good toughness. It is widely used for textiles, cigarette filters etc
Silicate residues such as coal fly ash and incinerator fly ash have good potential for use in glass-ceramics. This is a report on the success of trying to incorporate these materials into glass-ceramics. Production, properties and structure of the materials are covered.
Pyrophyllite is soft ceramic material. Its softness allows it to be machines using conventional machining techniques and tools. Applications include machined ceramics for insulators and in tile and refractory formulations and fillers for paints, plastics and rubbers.
Gutta percha is a form of natural rubber introduced to the west in 1843. It was used for wire insulation for submarine telephone cales, golf balls and jewellery making. It has few uses today except in dentistry and conveyor belts.
Typical properties of fibre reinforced polymers are outlined as well as those that can be modified/improved through composition changes. Properties of E-glass fibre and woven roving reinforced unsaturated polyester resins of varying compositions are also provided.
Additives can provide a third phase to polymer matrix composites in addition to the reinforcement and matrix phases. Such materials may include fillers, fire retardants or external additives which can be used for a variety of reasons, including the tailoring of properties.
The fire resistance levels of brick walls are influenced by factors such as structural adequacy, integrity insulation, and dimensions.
The bond between bricks and mortar is largely governed by the rate of water absorption of the brick and the ability of the mortar to retain the water.
A bricks' resistance to attack by soluble salts will dictate where it can be used.