Plastic
-Plastics are lightweight, resilient, and generally resistant to corrosion and moisture can be molded and formed into complex shapes.
-Plastics can be generally defined as chainlike molecular structures that are made by either altering natural products or by transforming petroleum, natural gas, or coal products into object.
Acrylic
Process
There are many ways to process plastics; these are the main methods:
-Injection molding: allows for a wide range of opportunities in designing and creating any plastic form.
-Casting: liquid form rather than a granule or pellet. It is not normally used in mass production, but rather to produce a
higher quality plastic product. It is however one of the simplest and most accessible means of producing a custom
designed plastic form.
-Extrusion: used for the production of thermoplastic pipes, sheets, films, and unusual shapes. Their lengths can be very
greatly, but extrusions are consistent in cross section.
Limitation
-Acrylic plastics are available in three forms: flat sheets, elongated shapes (rods and tubes), and molding powder
-acrylic sheet = thicknesses from 0.06 to 6.0 inches (0.16-15 cm) and widths from 3 feet (0.9 m) up to several hundred feet
Usage
-Furniture, windows
-Signage, glazing
Environmental impact
-Acrylic plastic is not easily recycled. It is considered a group 7 plastic among recycled plastics and is not collected for
recycling in most communities.
-Large pieces can be reformed into other useful objects if they have not suffered too much stress, crazing, or cracking, but
this accounts for only a very small portion of the acrylic plastic waste.
-Acrylic plastics are not readily biodegradable. Some acrylic plastics are highly flammable and must be protected from
sources of combustion.
Advantages
-Acrylic is easily fabricated and machined and when heated can be formed into different shapes.
-Good resistance to weather.
-Acrylic sheet is lightweight- usually less than half the weight of a piece of glass, and has moderate resistance to shrinkage and dimensional instability.
-Most valuable characteristic is its transparency, allowing as much as 92% overall light transmission.
- Acrylic sheet is 8 to 10 times stronger than glass of the same thickness.
Disadvantages
-Can scratch more easily than glass.
-Acrylic plastics manufacturing involves highly toxic substances which require careful storage, handling, and disposal.
- It is more expensive than glass.
-If exposed to a direct flame it will melt and eventually burn.
Company in Australia
Reference
-Materials for architectural design, By Victoria Ballard Bell with Patrick Rand
-http://www.enotes.com/how-products-encyclopedia/acrylic-plastic
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