Plastic Containers

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Every variety of plastic containers shares a few traits in common with all other varieties of plastic containers. These traits are the reason for the demand for plastic containers over the past half-century. The word "plastic" is a derivative of Latin and Greek adjectives that described an object that could be molded or shaped. Modern plastic materials don't betray their namesake: any plastic material can be molded or shaped into any conceivable configuration. For this reason, and because of other reasons like plastics' strength, durability, customizability and low cost, plastic materials are used in more applications across markets and industries than can be counted. In developed countries, utility of plastic containers begins for some people the moment they are born and fed with a plastic bottle or washed in a plastic tub or bin. Plastic storage containers, plastic crates, plastic totes, plastic jars and plastic buckets share a general ambiguity of purpose, but their value in specific applications is not capable of question. And though plastic food containers, catch basins and shipping containers may seem limited in their applications, their importance to economies worldwide cannot be understated.

Industries in nations of every level of economic development rely heavily on plastic containers. From North America to sub-Saharan Africa, plastic water bottles and other plastic containers litter city streets and rural routes. In wealthy countries and in countries gripped by scarcity, plastic containers are easy to come by. Indeed, in both extremes they have become essential for life; the market for portable water containers is enormous in countries without municipal water sources, and in western countries only a minority (however substantial) of food containers are not made of plastic. It would be difficult, for example, to find commercially packaged peanut butter in glass jars anywhere in the United States. Also, industrial manufacturers and distributors of all varieties rely on plastic containers in their day-to-day operations. Warehouses often store and transport materials in plastic totes or bins, and factories use plastic tubs to collect products when they emerge from production machinery. Landscaping companies, municipalities and consumers make use of plastic catch basins to control the flow of rainwater and to prevent pollution of water sources. Even the containers used to recycle other plastic containers are made of plastic. Plastic is chosen over competing container materials because of its durability, versatility, pliability and because of the low cost of manufacturing it.

Most plastics are refined and processed hydrocarbons. There are some exceptions, such as biodegradable containers made from processed corn, but the overwhelming majority of plastics are derivatives of petrochemicals. These plastic varieties begin their lives in reservoirs of crude oil and natural gas. After a series of refinement and development processes, these raw materials can be converted into styrene, ethylene glycol, vinyl chloride and many others - the main ingredients of thermoplastics. Thermoplastics, under the right conditions, can be shaped and molded into useful products (thermosets, another kind of refined plastic, are less commonly manufactured and cannot be remolded once set). There are many processes by which plastics are molded. The processes relevant to the creation of plastic containers are injection molding and blow molding. In both processes, raw plastic material (stock) is placed in a conveyance channel where a long screw forces it toward a mold. The friction and pressure caused by the turning screw, combined with heat from heating elements along the channel, liquefies the stock. In injection molding, the molten plastic is forced into a mold designed to give the plastic a certain shape. In blow molding, the molten plastic enters the mold in the same way but is then shaped further by compressed air which is forced into the mold cavity; this causes the plastic to expand and become hollow in predetermined places. In some cases, a combination of injection and blow molding is necessary to form complex shapes. At the end of the process, the plastic cools and hardens and is ejected from the mold.

For all of their positive qualities, plastic storage containers are not without their flaws. The high global demand for plastics, most of which are refined from crude oil, contributes to the global demand for oil. High demand for oil has nuanced implications for the planet and its people. Notwithstanding those implications, if not properly disposed of, plastic products can play a large role in environmental degradation. Despite improvements in the recyclability of many plastic products and the elimination of some deficiencies of plastics composition, it is up to end users to dispose of plastic containers in a way that minimizes waste and environmental degradation. Influencing end user behavior to that end has proven difficult for industry and governments. A combination of such efforts and continued research into alternatives to hydrocarbon-derived plastics are the only known solutions to the problem of plastic waste disposal.

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Plastic Container Types

• Attached lid containers are containers with lids that are attached, usually by hinges, for product protection and to prevent loss of lid.
  
• Bottom-hinged containers have an opening on top and bottom. The bottom opening usually locks and unlocks for easy product removal.
  
• Bulk containers are containers to hold, move and ship large quantities of product together.
  
• Catch basins are cisterns located at the ends of gutters.
• Drums are containers to hold bulk product, food, liquor, wine, water, parts and various other materials, available in various sizes. (http://www.iqsdirectory.com/55-gallon-drums/)
  
• Holding tanks are built similarly to a septic tank to contain wastewater until it can be removed for treatment and disposal.
  
• Hoppers are containers for short-term storage, designed so stored material can be easily discarded.
  
• Lockers are used for safe, private storage of items like clothes or valuables, used mainly in changing rooms, available in various sizes and styles.
  
• Nestable containers are containers that can fit together or inside one another for easy storage.
  
• Neutralization tanks are containers to collect and neutralize acidic and basic waste water for safe removal.
  
• Openhead containers have a cover or top that is removable.
  
• Overpack containers are for damaged drums and other leaking containers, usually containing hazardous material.
  
• Packaging containers are usually commercial in nature, sometimes custom designed for ease of use and presentation depending on the product contained.
  
• Plastic bins are storage boxes made out of various plastic materials.
• Plastic bottles are small containers used for the transportation, storage and distribution of products in small quantities
• Plastic boxes are storage containers made from plastic materials.
• Plastic buckets are smaller, round plastic containers used for storage, distribution and many other applications.
• Plastic crates are storage and distribution containers of variable size and construction.
• Plastic food containers are usually made of polypropylene and come in a variety of shapes and sizes to accommodate different quantities of food.
• Plastic jars are small plastic containers usually used for the distribution of consumer products in small quantities.
• Plastic shipping containers are any plastic containers used for shipping products.
• Plastic storage containers are stackable containers are used to store various goods.
• Plastic totes can be plastic baskets, usually with handles, to hold or carry products/materials.
• Plastic tubs are storage or distribution containers that are used in commercial and industrial applications.
• Reusable containers are containers that can be reprocessed for repeated uses.
  
• Stackable containers are containers that stack easily without causing damage to one another or the product, and sometimes may "lock" with surrounding containers.
  
• Tanks are containers used for storage and transport and to dispense liquids usually in bulk or heavy quantities. (http://www.iqsdirectory.com/plastic-tanks/)
  
• Tighthead containers have attached, non-removable covers or tops.
  
• Tooling boxes are plastic cases with small compartments to store punches and dies, available in various sizes and capacities.
  

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Plastic Container Terms

Blow Mold - To make hollow objects by extruding plastic into a chamber that is blown outward to take the shape of the plastic container mold cavity.
 
British Thermal Unit (BTU) - The amount of heat necessary to heat one pound of water one degree Fahrenheit.
 
Coextrusion - A manufacturing process in which plastic containers are blow-molded with walls containing two or more layers of different materials. This manufacturing process often uses recycled plastic materials.
 
Extrusion - The most common of the plastic container processing techniques, covering a vast range of applications in which plastic resins are melted, heated and pumped for plastic container processing.
 
HazMat - Hazardous materials. The Environmental Protection Agency has standards for plastics regarding the ability to handle various HazMat substances.
 
High Density Polyethylene (HDPE) Colored (Pigmented) - Often used for bleach, liquid detergents, motor oil and other household and automotive products. These plastic containers commonly bear the number "2" in the recycling triangle symbol on the bottom of many plastic storage containers.
 
High Density Polyethylene (HDPE) Natural (Non-pigmented) - Commonly used for plastic containers and plastic storage containers used to hold liquid dairy products, juice and other household products. These plastic containers usually bear the number "2" in the recycling triangle at the bottom of the plastic storage container.
 
High Density Polyethylene (HDPE) Wide - Natural and pigmented, these plastic containers are often used to store butter and other food products as plastic storage tubs, some medicine bottles and 5-gallon plastic buckets. These plastic containers usually display the number "2" in the recycling triangle symbol at the bottom of the plastic storage container.
 
Injection Mold - Under pressure, heated plastic granules are "injected" into a mold, where the molten plastic hardens into the designated plastic container shape.
 
In-line Fluorinated - A term that describes the chemical modification of the interior of HDPE plastic containers caused by fluorine gas as they are blown. This chemical reaction forms an inner barrier that withstands solvent-based chemicals, making the plastic containers suitable for the packaging of janitorial, industrial and consumer products.

ISO Container - Intermodal plastic shipping containers used to transport freight and designed for shipping and transportation by more than just one mode like ship and rail. Plastic shipping container sizes vary but typical sizes of these plastic containers are 20 feet and 40 feet; the standard width of ISO plastic containers is 8 feet, and the standard heights for ISO plastic containers are 8 feet 6 inches and 9 feet 6 inches.

Low Density Polyethylene (LDPE) - Used for plastic shrink-wrap, plastic bags, garment bags, dry cleaning bags and squeezable plastic food bottles.

Monomer - A comparatively simple compound that can react to form a polymer. The core element in plastic containers.
 
Polyethylene Teraphtalate (PET) Slim - Color and clear, these plastic containers are used to contain cosmetics, water, salad dressings and cleaners. These plastic containers usually bear number "1" in the recycling triangle at the bottom of of the plastic storage container.
 
Polymer - A compound, natural or synthetic, whose structure can be represented by a repeated small unit. Synthetic polymers are formed by condensation polymerization of monomers; some polymers are rubber, some plastics.

Polypropylene (PP) - Often used in plastic food containers designed for margarine and yogurt plastic containers, caps for plastic containers, and wrapping to replace cellophane on plastic storage containers like medicine bottles.

Polystyrene (PS) - Used for plastic containers such as egg cartons, fast food trays, disposable plastic silverware, cups and compact disc jackets.

Polyvinyl Chloride (PVC) - Used in plastic containers like food wrap, vegetable oil bottles and blister packaging.

Recycling - The cycle of actions by which discarded materials are collected, sorted, processed and transformed back into raw materials and then used in the production of new plastic containers.
 
Resin - Most resins are polymers, a class of solid or semi-solid organic products of natural or synthetic origin, of high molecular weight with no definite melting point.

Rigid Plastic Containers - Any formed plastic container or molded plastic container that retains its shape when full or empty. This classification of plastic containers does not include plastic storage bottles.
 
Rotational Molding - Hollow plastic container molds filled with powdered resin that swings the entire plastic container mold into a furnace that melts the powder, making it stick to the plastic container mold as it cools. The plastic container mold slowly rotates and water is used to cool the plastic container mold while the plastic hardens into a hollow part. 

Tare Weight - Weight of plastic containers when they are empty.
 
Thermoforming - A process of heating a thermoplastic sheet to an effective temperature and then forming it into a completed plastic container shape by means of heat or force.

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