Friday, March 5, 2010

The Different Types of Plastics and Their Uses

ABS : a terpolymer made from three monomers, acrylonitrile, butadiene and styrene. Acrylonitrile and styrene provide chemical resistance, butadiene adds impact resistance and makes the plastic suitable for furniture, computer housings etc.

Acrylic: a hard thermoplastic made from acrylic acid or a derivative of acrylic acid. Best known as a glass substitute, typically under the trade names Perspex, Lucite and Plexiglas.

Amino plastics: Plastics made from ammonia based compounds, namely urea formaldehyde and melamine formaldehyde.

Bakelite : really a trade name but frequently used as a generic name for phenol formaldehyde (phenolic).

Cellophane : A Du Pont trade name for film made from regenerated wood pulp (cellulose).

Cellulose : The fibrous matter in all plant cells, with a long chain molecular structure. The most common sources used for making plastics are cotton fibres and wood pulp

Cellulose acetate: A tough thermplastic made from cellulose in the form of cotton linters, treated with acetic acid and acetic anhydride. Used for many domestic mouldings such as spectacle frames, toothbrush handles, and as transparent packaging film.

Cellulose acetate butyrate: A thermoplastic made from cellulose treated with acetic and butyric acids. Transparent, opaque or coloured, with excellent moulding qualities, used where more moisture resistance and dimensional stability than cellulose acetate is required.

Copolymer: A plastic made by polymerizing two monomers, eg styrene and acrylonitrile .

Elastomer: A synthetic plastic with the flexible properties of rubber.

Epoxy resin: A very tough thermosetting resin used as a coating, or reinforced to make mouldings or laminates.

Ester : A compound produced by the reaction between an acid and an alcohol.

GRP : Glass reinforced polyester, ie polyester resin strengthened by glass fibres, making the resin, which has no strength of its own, into a very tensile material. Widely used to build boats, furniture and cars.

HIPS : High impact polystyrene

LLDPE : Linear low density polyethylene, a new type of low density polythene.

Melalmine : Melamine formaldehyde, a thermoset produced by reacting (triaminotriazine) with formaldehyde. A tough glossy plastic usually strengthened with a filler of wood pulp.

Monomer: A simple low molecular weight compound. Polymerization links monomers together to form high molecular weight polymers.

Nylon: Not one material but a group of very tough and flexible materials called polyamides. Thermoplastic and usually found as fibres or used solid, as gears, zips and more recently as dyed jewellery.

Phenolic: abbreviated version of phenol - formaldehyde. Phenolic is usually reinforced with a filler, but cast phenolic has no filler and can be translucent. It can be easily coloured and is used decoratively for jewellery, radio cabinets and all kinds of ornaments.

Polycarbonate : A very tough thermoplastic, usually found as a substitute for glass, eg: vandal proof telephone kiosks,bullet proof shields, baby bottles and picnicware.

Polyesters : Complex ester compounds which are thermosetting and can be polymerized at room temperature, eg GRP.

Polymer : Another word for a plastic material: one which has been made from chains of molecules of one or more monomers. Polymers (plastics) are organic substances, made from hundreds or thousands of molecules linked together in a repeating chain pattern (also known as macromolecules).

Polymerization : The chemical process of linking monomers to form new compounds called polymers. For example,ethylene is polymerized into polyethylene, (polythene for short).

Polypropylene : A thermoplastic polymerized from propene, very close to polythene in molecular structure, but harder, stronger and less flexible.

Polystyrene : A brittle.water white thermoplastic polymerized from styrene - (phenylethylene). The brittleness is overcome by adding some butadiene, which results in toughened polystyrene also known as high impact polystyrene (HIPS), a copolymer of butadiene and styrene. Expanded polystyrene is the rigid white foam used for packaging.

Wednesday, March 3, 2010

Plastics and Its Many Uses to Man

Before plastics were introduced many decades ago, people used things like straw baskets, glass jars, paper and cloth bags, leather footwear, wooden toys, glass dishes, wood boxes, cotton shower curtains and organic fiber clothing like cotton, silk and linen. Now, almost all things around you are plastics. Even pipes, bottles, containers and garments are now made of plastic. Newly designed electronic equipment are mostly made of plastic material.

Plastic material items have become an indispensable part of our daily lives as many objects we are using daily are made from some kind of plastic. Plastic has many benefits over other materials since it costs much less, resists corrosion and is highly flexible and durable.

While all these properties make it the perfect material for making many substances, waste plastic material can be a threat towards the atmosphere. But regular information on proper waste disposal could resolve this problem. A global movement to educate people on the proper handling of these plastic wastes could be a lot of help to preserve our environment.

One way of helping the environment is to recycle the plastics. Although plastics are more complicated than it looks, having a way of recycling them would be a lot of help. Plastics are categorized into grade levels. Under the plastic containers have numbers indicating grade level 1 to 7. Plastic 1 and 2 are the commonly used plastics like soda bottles and cooking oil bottles. Plastic #1, the so called PET (polyethelyne terephthalate), are the most commonly used plastic and the most recyclable one. Plastic #2 also known as high density polyethelene (HDPE) are used for detergent bottles and many other food containers and a little harder than the PET. Plastics #3 too #7 needs an established plastic recyclable plants for them to be reused as they require a much bigger and complicated equipment to process.

Plastics nowadays have been utilized more frequently than ever before because of the many advantages and the flexibility it can offer to almost any kind of industries. People just have to know how to handle its waste disposal and recycle as much as possible.