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High-density Polyethylene
High-density polyethylene (HDPE) or polyethylene high-density (PEHD) is a thermoplastic polymer produced from the monomer ethylene. It is sometimes called "alkathene" or " polythene" when used for HDPE pipes. With a high strength-to-density ratio, HDPE is used in the production of plastic bottles, corrosion-resistant piping, geomembranes and plastic lumber. HDPE is commonly recycled, and has the number "2" as its resin identification code. In 2008, the global HDPE market reached a volume of more than 30 million tons. Properties HDPE is known for its high strength-to-density ratio. The density of HDPE ranges from 930 to 970 kg/m3. Although the density of HDPE is only marginally higher than that of low-density polyethylene, HDPE has little branching, giving it stronger intermolecular forces and tensile strength (38 MPa versus 21 MPa) than LDPE. The difference in strength exceeds the difference in density, giving HDPE a higher specific strength. It is also harder and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbol Resin Code 2 HDPE
A symbol is a mark, sign, or word that indicates, signifies, or is understood as representing an idea, object, or relationship. Symbols allow people to go beyond what is known or seen by creating linkages between otherwise different concepts and experiences. All communication is achieved through the use of symbols: for example, a red octagon is a common symbol for " STOP"; on maps, blue lines often represent rivers; and a red rose often symbolizes love and compassion. Numerals are symbols for numbers; letters of an alphabet may be symbols for certain phonemes; and personal names are symbols representing individuals. The academic study of symbols is called semiotics. In the arts, symbolism is the use of a concrete element to represent a more abstract idea. In cartography, an organized collection of symbols forms a legend for a map. Etymology The word ''symbol'' derives from the late Middle French masculine noun , which appeared around 1380 in a theological sense signifying a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polypropylene
Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer Propene, propylene. Polypropylene belongs to the group of polyolefins and is Crystallization of polymers#Degree of crystallinity, partially crystalline and Chemical polarity#Nonpolar molecules, non-polar. Its properties are similar to polyethylene, but it is slightly harder and more heat-resistant. It is a white, mechanically rugged material and has a high chemical resistance. Polypropylene is the second-most widely produced Commodity plastics, commodity plastic (after polyethylene). History Phillips Petroleum chemists J. Paul Hogan and Robert Banks (chemist), Robert Banks first demonstrated the polymerization of propylene in 1951. The stereoselective polymerization to the isotactic was discovered by Giulio Natta and Karl Rehn in March 1954. This pioneering discovery led to large-scale commercial producti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bottle Cap
A bottle cap or bottle top is a common closure for the top opening of a bottle. A cap is sometimes colorfully decorated with the logo of the brand of contents. Metal caps with plastic backing are used for glass bottles, sometimes wrapped in decorative foil. Metal caps are usually either steel or aluminum, and of the crown cork type. Flip-top caps (like flapper closures) preceded such caps. Plastic caps are used for plastic bottles, functioning as screw caps, or plastic caps may have a pour spout rather than being detachable. Plastic caps are commonly made from polyethylene or polypropylene, and caps for plastic bottles are often made of a different type of plastic from the bottle. A cork stopper is another type of closure for the top of a bottle. Types Caps were originally designed to be pressed over and around the top of a glass bottle to grab a small flange on the bottleneck. Crown cork The crown cork was patented by William Painter on February 2, 1892 (U.S. Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3D Printer
3D printing, or additive manufacturing, is the construction of a three-dimensional object from a CAD model or a digital 3D model. It can be done in a variety of processes in which material is deposited, joined or solidified under computer control, with the material being added together (such as plastics, liquids or powder grains being fused), typically layer by layer. In the 1980s, 3D printing techniques were considered suitable only for the production of functional or aesthetic prototypes, and a more appropriate term for it at the time was rapid prototyping. , the precision, repeatability, and material range of 3D printing have increased to the point that some 3D printing processes are considered viable as an industrial-production technology; in this context, the term ''additive manufacturing'' can be used synonymously with ''3D printing''. One of the key advantages of 3D printing is the ability to produce very complex shapes or geometries that would be otherwise infeasibl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jerrycan
A jerrycan or jerrican (also styled jerry can or jerri can) is a fuel container made from pressed steel (and more recently, high-density polyethylene, high density polyethylene). It was designed in Germany in the 1930s for military use to hold of fuel or water, and saw widespread use by both Germany and the Allies of World War II, Allies during the Second World War. The development of the jerrycan was a significant improvement on earlier designs, which required tools and funnels to use, and it contained many innovative features for convenience of use and robustness. Today similar designs are used worldwide for fuel and water containers, in both military and civilian contexts. History The name of the jerrycan refers to its German origins, ''Jerry (WWII), Jerry'' being slang for Germans. The design was reverse engineered and subsequently copied, with minor modifications, by the Allies during the Second World War. German invention The ''Wehrmacht-Einheitskanister'' ("A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyethylene Terephthalate
Polyethylene terephthalate (or poly(ethylene terephthalate), PET, PETE, or the obsolete PETP or PET-P), is the most common thermoplastic polymer resin of the polyester family and is used in synthetic fibre, fibres for clothing, packaging, containers for liquids and foods, and thermoforming for manufacturing, and in combination with glass fibre for engineering resins. In 2016, annual production of PET was 56 million tons. The biggest application is in fibres (in excess of 60%), with bottle production accounting for about 30% of global demand. In the context of textile applications, PET is referred to by its common name, polyester, whereas the acronym ''PET'' is generally used in relation to packaging. PET used in non-fiber applications (i.e. for packaging) makes up about 6% of world polymer production by mass. Accounting for the >60% fraction of polyethylene terephthalate produced for use as polyester fibers, PET is the fourth-most-produced polymer after polyethylene (PE), polypr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monobloc (chair)
The Monobloc chair is a lightweight stackable polypropylene chair, usually white in color, often described as the world's most common plastic chair. The name comes from '' mono-'' ("one") and ''bloc'' ("block"), meaning an object forged in a single piece. History Variants of the one-piece plastic chair designed by Canadian Douglas C. Simpson in 1946 went into production with Allibert Group and Grosfillex Group in the 1970s. Other sources name the French engineer Henry Massonnet from Nurieux-Volognat with his "Fauteuil 300" from 1972 as the inventor of the monobloc. They were inspired by the ''Chair Universal 4867'' design by Joe Colombo in 1965, but no patents were filed for a monobloc chair design. Since then, millions have been manufactured around the world. Production and usage The Monobloc chair is so named because it is injection moulded from thermoplastic as one piece rather than being assembled from multiple pieces. Many variations and styles exist but all are des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mexico
Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundary, maritime boundaries with the Pacific Ocean to the west, the Caribbean Sea to the southeast, and the Gulf of Mexico to the east. Mexico covers 1,972,550 km2 (761,610 sq mi), and is the List of countries by area, thirteenth-largest country in the world by land area. With a population exceeding 130 million, Mexico is the List of countries by population, tenth-most populous country in the world and is home to the Hispanophone#Countries, largest number of native Spanish speakers. Mexico City is the capital and List of cities in Mexico, largest city, which ranks among the List of cities by population, most populous metropolitan areas in the world. Human presence in Mexico dates back to at least 8,000 BC. Mesoamerica, considered a cradle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Housewrap
Housewrap (or house wrap), also known by the genericized trademark homewrap (or home wrap), generally denotes a modern synthetic material used to protect buildings. Housewrap functions as a water-resistant layer, preventing rain or snow from getting into the wall assembly while allowing water vapor to pass to the exterior. It is NOT a weather resistant layer, as weather elements include sun, and housewraps can only be exposed for a few months before being damaged, and temperature, and housewraps do not insulate. If moisture from either direction is allowed to build up within stud or cavity walls, mold and rot can set in and fiberglass or cellulose insulation will lose its R-value because of the heat-conducting moisture. House wrap may also serve as an air barrier if it is sealed carefully at seams and supported to resist wind loads. Housewrap is a replacement for the older tar paper or asphalt saturated felt on walls. It is lighter in weight, available in much wider rolls, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drinking Water
Drinking water or potable water is water that is safe for ingestion, either when drunk directly in liquid form or consumed indirectly through food preparation. It is often (but not always) supplied through taps, in which case it is also called tap water. The amount of drinking water required to maintain good health varies, and depends on physical activity level, age, health-related issues, and environmental conditions. This 2004 article focuses on the USA context and uses data collected from the US military. For those who work in a hot climate, up to a day may be required. About 1 to 2 billion people lack safe drinking water. Water can carry vectors of disease and is a major cause of death and illness worldwide. Developing countries are most affected by unsafe drinking water. Sources Potable water is available in almost all populated areas of the world, although it may be expensive, and the supply may not always be sustainable. Sources where drinking water is commo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solvent
A solvent (from the Latin language, Latin ''wikt:solvo#Latin, solvÅ'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a Solution (chemistry), solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for Chemical polarity#Polarity of molecules, polar molecules, and the most common solvent used by living things; all the ions and proteins in a Cell (biology), cell are dissolved in water within the cell. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. Specific uses for Organic compound, organic solvents are in dry cleaning (e.g. tetrachloroethylene); as paint thinners (toluene, turpentine); as nail polish removers and solvents of glue (acetone, methyl acetate, ethyl acetate); in spot removers (hexane, petrol ether); in detergents (D-limonene, citrus terpenes); and in perfumes (ethanol). Solvents find various applications in chemical, pharmaceutical, oil, and gas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reaction
A chemical reaction is a process that leads to the chemistry, chemical transformation of one set of chemical substances to another. When chemical reactions occur, the atoms are rearranged and the reaction is accompanied by an Gibbs free energy, energy change as new products are generated. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the Atomic nucleus, nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive Chemical element, elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reagent, reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more Product (c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
