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Hypalon is a chlorosulfonated polyethylene (CSPE) synthetic rubber (CSM) noted for its resistance to chemicals, temperature extremes, and ultraviolet light. It was a product of DuPont Performance Elastomers, a subsidiary of DuPont. [1] Hypalon as it is now known in the marine industry today is a remarketed version of the old Hypalon using an additional layer of neoprene (cr) so the new chemical formulation is csm/cr. [2]
Polyethylene is treated with a mixture of chlorine and sulfur dioxide under UV-radiation. The product contains 20-40% chlorine. The polymer also contains a few percent chlorosulfonyl (ClSO2-) groups. These reactive groups allow for vulcanization, which strongly affects the physical durability of the products. An estimated 110,000 tons/y were produced in 1991. [1]
DuPont Performance Elastomers announced on May 7, 2009, that it intended to close its manufacturing plant in Beaumont, Texas, by June 30, 2009. This was DPE's sole plant for CSM materials. The company was therefore exiting the business for Hypalon and its related product, Acsium. [3] The plant closure was delayed until April 20, 2010, in response to customer requests.
A polymer is a substance or material consisting of very large molecules linked together into chains of repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals.
Polyurethane refers to a class of polymers composed of organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane is produced from a wide range of starting materials. This chemical variety produces polyurethanes with different chemical structures leading to many different applications. These include rigid and flexible foams, and coatings, adhesives, electrical potting compounds, and fibers such as spandex and polyurethane laminate (PUL). Foams are the largest application accounting for 67% of all polyurethane produced in 2016.
The chemical industry comprises the companies and other organizations that develop and produce industrial, specialty and other chemicals. Central to the modern world economy, it converts raw materials into commodity chemicals for industrial and consumer products. It includes industries for petrochemicals such as polymers for plastics and synthetic fibers; inorganic chemicals such as acids and alkalis; agricultural chemicals such as fertilizers, pesticides and herbicides; and other categories such as industrial gases, speciality chemicals and pharmaceuticals.
Petrochemicals are the chemical products obtained from petroleum by refining. Some chemical compounds made from petroleum are also obtained from other fossil fuels, such as coal or natural gas, or renewable sources such as maize, palm fruit or sugar cane.
Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging (plastic bags, plastic films, geomembranes and containers including bottles, etc.). As of 2017, over 100 million tonnes of polyethylene resins are being produced annually, accounting for 34% of the total plastics market.
A thermoplastic, or thermosoftening plastic, is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling.
Neoprene is a family of synthetic rubbers that are produced by polymerization of chloroprene. Neoprene exhibits good chemical stability and maintains flexibility over a wide temperature range. Neoprene is sold either as solid rubber or in latex form and is used in a wide variety of commercial applications, such as laptop sleeves, orthopaedic braces, electrical insulation, medical gloves, liquid and sheet-applied elastomeric membranes or flashings, and automotive fan belts.
Aramid fibers, short for aromatic polyamide, are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic-rated body armor fabric and ballistic composites, in marine cordage, marine hull reinforcement, as an asbestos substitute, and in various lightweight consumer items ranging from phone cases to tennis rackets.
The Dow Chemical Company is an American multinational corporation headquartered in Midland, Michigan, United States. The company was among the three largest chemical producers in the world in 2021. It is the operating subsidiary of Dow Inc., a publicly traded holding company incorporated under Delaware law.
An elastomer is a polymer with viscoelasticity and with weak intermolecular forces, generally low Young's modulus (E) and high failure strain compared with other materials. The term, a portmanteau of elastic polymer, is often used interchangeably with rubber, although the latter is preferred when referring to vulcanisates. Each of the monomers which link to form the polymer is usually a compound of several elements among carbon, hydrogen, oxygen and silicon. Elastomers are amorphous polymers maintained above their glass transition temperature, so that considerable molecular reconformation is feasible without breaking of covalent bonds. At ambient temperatures, such rubbers are thus relatively compliant and deformable. Their primary uses are for seals, adhesives, and molded flexible parts.
An O-ring, also known as a packing or a toric joint, is a mechanical gasket in the shape of a torus; it is a loop of elastomer with a round cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, forming a seal at the interface.
A synthetic rubber is an artificial elastomer. They are polymers synthesized from petroleum byproducts. About 32 million metric tons of rubbers are produced annually in the United States, and of that amount two thirds are synthetic. Synthetic rubber, just like natural rubber, has many uses in the automotive industry for tires, door and window profiles, seals such as O-rings and gaskets, hoses, belts, matting, and flooring. They offer a different range of physical and chemical properties which can improve the reliability of a given product or application. Synthetic rubbers are superior to natural rubbers in two major respects: thermal stability, and resistance to oils and related compounds. They are more resistant to oxidizing agents, such as oxygen and ozone which can reduce the life of products like tires.
A polyolefin is a type of polymer with the general formula (CH2CHR)n where R is an alkyl group. They are usually derived from a small set of simple olefins (alkenes). Dominant in a commercial sense are polyethylene and polypropylene. More specialized polyolefins include polyisobutylene and polymethylpentene. They are all colorless or white oils or solids. Many copolymers are known, such as polybutene, which derives from a mixture of different butene isomers. The name of each polyolefin indicates the olefin from which it is prepared; for example, polyethylene is derived from ethylene, and polymethylpentene is derived from 4-methyl-1-pentene. Polyolefins are not olefins themselves because the double bond of each olefin monomer is opened in order to form the polymer. Monomers having more than one double bond such as butadiene and isoprene yield polymers that contain double bonds (polybutadiene and polyisoprene) and are usually not considered polyolefins. Polyolefins are the foundations of many chemical industries.
Silicone rubber is an elastomer composed of silicone—itself a polymer—containing silicon together with carbon, hydrogen, and oxygen. Silicone rubbers are widely used in industry, and there are multiple formulations. Silicone rubbers are often one- or two-part polymers, and may contain fillers to improve properties or reduce cost. Silicone rubber is generally non-reactive, stable, and resistant to extreme environments and temperatures from −55 to 300 °C while still maintaining its useful properties. Due to these properties and its ease of manufacturing and shaping, silicone rubber can be found in a wide variety of products, including voltage line insulators; automotive applications; cooking, baking, and food storage products; apparel such as undergarments, sportswear, and footwear; electronics; medical devices and implants; and in home repair and hardware, in products such as silicone sealants.
An acrylate polymer is any of a group of polymers prepared from acrylate monomers. These plastics are noted for their transparency, resistance to breakage, and elasticity.
FKM is a family of fluorocarbon-based fluoroelastomer materials defined by ASTM International standard D1418, and ISO standard 1629. It is commonly called fluorine rubber or fluoro-rubber. FKM is an abbreviation of Fluorine Kautschuk Material. All FKMs contain vinylidene fluoride as the common monomer, to which different other monomers are added for specific types and functionalities, fitting the desired application.
Polymer engineering is generally an engineering field that designs, analyses, and modifies polymer materials. Polymer engineering covers aspects of the petrochemical industry, polymerization, structure and characterization of polymers, properties of polymers, compounding and processing of polymers and description of major polymers, structure property relations and applications.
Forensic polymer engineering is the study of failure in polymeric products. The topic includes the fracture of plastic products, or any other reason why such a product fails in service, or fails to meet its specification. The subject focuses on the material evidence from crime or accident scenes, seeking defects in those materials that might explain why an accident occurred, or the source of a specific material to identify a criminal. Many analytical methods used for polymer identification may be used in investigations, the exact set being determined by the nature of the polymer in question, be it thermoset, thermoplastic, elastomeric or composite in nature.
The Charles Goodyear Medal is the highest honor conferred by the American Chemical Society, Rubber Division. Established in 1941, the award is named after Charles Goodyear, the discoverer of vulcanization, and consists of a gold medal, a framed certificate and prize money. The medal honors individuals for "outstanding invention, innovation, or development which has resulted in a significant change or contribution to the nature of the rubber industry". Awardees give a lecture at an ACS Rubber Division meeting, and publish a review of their work in the society's scientific journal Rubber Chemistry and Technology.
