Plastic is a material that has been used by humans for centuries. It is made from a variety of natural and synthetic materials and can be molded into any shape. Plastic is lightweight, durable, and easy to clean. It is also resistant to heat, cold, and moisture. plastic surgery
The first recorded use of plastic was in the year 1624 when an English man named John Wood used it to make combs. In 1869, an American inventor named John Wesley Hyatt created the first synthetic plastic called celluloid. Celluloid was made from cellulose, a substance found in plants.
In 1907, Leo Baekeland invented Bakelite, the first completely synthetic plastic. Bakelite was made from coal tar and did not require cellulose as its base material. Bakelite was strong and heat-resistant making it ideal for electrical insulators and telephone casings.
Bakelite’s success led to the development of other plastics such as polystyrene (PS), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), acrylics, nylons, and polyesters just to name a few.
Today there are over 50 types of commercial plastics available on the market each with their own unique set of properties suited for specific applications . For example:
Polyethylene terephthalate (PET or PETE) is clear, stiff, shatter-resistant ,and has good gas and moisture barrier properties making it ideal for food packaging such as soft drinks bottles .
Low-density polyethylene(LDPE)is flexible ,waxy ,and translucent .It has good chemical resistance but poor heat resistance making it ideal for food wrappers ,plastic bags ,and piping .
High-density polyethylene(HDPE)is opaque ,stiffer than LDPE ,and has very good chemical resistance .It does not have good heat resistance so it is often used in milk jugs ,detergent bottles ,and cutting boards .