Nearly all forms of plastic are made from natural gas, oil, and some types of vegetation. Plastics have been demonized as a symbol of all that is wrong with society, but nearly everyone still uses them. Even the most vocal opponents express their disapproval using a plastic computer keyboard. The manufacturing method that makes these finished products possible is called thermoforming.
The environmental impact of hydrocarbon use is difficult to ignore. Surprisingly, production of plastics uses less than 3% of all the oil and gas burned each year in the United States by vehicles. That is still a huge number, but illustrates how halting all production of plastic would do very little to end reliance on oil as a primary fuel, and would force consumer prices upward.
The process begins by turning raw hydrocarbons into sheets of acrylic, polyvinyl chloride, polypropylene or other chemically similar polymers. They arrive on site in varying thicknesses, and are warmed until they become malleable, but not runny. Employing one of the three most common methods of production, the warm material is then molded, cooled, and the excess cut away. The result is a durable component.
The sheets are commonly processed using radiant electrical heat coming from devices positioned around five inches away. The type of polymer being used determines how long the heat must be applied. Once pliable, there are three primary methods of achieving the final shape. The first is called vacuum forming, which uses negative pressure to draw the warm plastic into a mold.
When a positive force is used, it is called pressure forming. Because vacuum processes are naturally limited, positive pressure can reach higher levels, making the process more versatile. The raw plastic is usually pre-stretched in order to avoid an uneven thickness over corners. After being applied, trapped air is released from the mold, and the product is cleaned up.
Mechanical forming uses both positive and negative molds. When plastic sheeting is placed between the two, pressure is applied, and the material assumes the shape and texture of the space between pieces. This gives manufactures better control over detailing, but is somewhat more expensive. No matter which process is being used, only thermoplastics can be reheated successfully.
Thicker sheets are used to make different vehicle components, are molded into health care accessories, and even make an appearance in the bathroom. Thinner gauge plastic sheeting is used to package cosmetics, small individual products like screws, and fresh and processed foods. While not yet biodegradable, recycling and disposal methods have been greatly improved.
The environmental impact of hydrocarbon use is difficult to ignore. Surprisingly, production of plastics uses less than 3% of all the oil and gas burned each year in the United States by vehicles. That is still a huge number, but illustrates how halting all production of plastic would do very little to end reliance on oil as a primary fuel, and would force consumer prices upward.
The process begins by turning raw hydrocarbons into sheets of acrylic, polyvinyl chloride, polypropylene or other chemically similar polymers. They arrive on site in varying thicknesses, and are warmed until they become malleable, but not runny. Employing one of the three most common methods of production, the warm material is then molded, cooled, and the excess cut away. The result is a durable component.
The sheets are commonly processed using radiant electrical heat coming from devices positioned around five inches away. The type of polymer being used determines how long the heat must be applied. Once pliable, there are three primary methods of achieving the final shape. The first is called vacuum forming, which uses negative pressure to draw the warm plastic into a mold.
When a positive force is used, it is called pressure forming. Because vacuum processes are naturally limited, positive pressure can reach higher levels, making the process more versatile. The raw plastic is usually pre-stretched in order to avoid an uneven thickness over corners. After being applied, trapped air is released from the mold, and the product is cleaned up.
Mechanical forming uses both positive and negative molds. When plastic sheeting is placed between the two, pressure is applied, and the material assumes the shape and texture of the space between pieces. This gives manufactures better control over detailing, but is somewhat more expensive. No matter which process is being used, only thermoplastics can be reheated successfully.
Thicker sheets are used to make different vehicle components, are molded into health care accessories, and even make an appearance in the bathroom. Thinner gauge plastic sheeting is used to package cosmetics, small individual products like screws, and fresh and processed foods. While not yet biodegradable, recycling and disposal methods have been greatly improved.
About the Author:
Genevive B. Mata has over 20 years of professional sales experience, 10 of them directly in the plastic pallets and materials handling industry. On her spare time she works on applied-sustainability projects. If you are interested in plastic pallets price, she suggests you check out her friends PTM.
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