|
Polyisocyanurate
Polyisocyanurate (), also referred to as PIR, polyiso, or ISO, is a thermoset plastic typically produced as a foam and used as rigid thermal insulation. The starting materials are similar to those used in polyurethane (PUR) except that the proportion of methylene diphenyl diisocyanate (MDI) is higher and a polyester-derived polyol is used in the reaction instead of a polyether polyol. The resulting chemical structure is significantly different, with the isocyanate groups on the MDI trimerising to form isocyanurate groups which the polyols link together, giving a complex polymeric structure. Manufacturing The reaction of (MDI) and polyol takes place at higher temperatures compared with the reaction temperature for the manufacture of PUR. At these elevated temperatures and in the presence of specific catalysts, MDI will first react with itself, producing a stiff, ring molecule, which is a reactive intermediate (a tri-isocyanate isocyanurate compound). Remaining MDI and the tri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Building Insulation Materials
Building insulation materials are the building materials which form the thermal envelope of a building or otherwise reduce heat transfer. Insulation may be categorized by its composition (natural or synthetic materials), form (batts, blankets, loose-fill, spray foam, and panels), structural contribution (insulating concrete forms, structured panels, and straw bales), functional mode (conductive, radiative, convective), resistance to heat transfer, environmental impacts, and more. Sometimes a thermally reflective surface called a radiant barrier is added to a material to reduce the transfer of heat through radiation as well as conduction. The choice of which material or combination of materials is used depends on a wide variety of factors. Some insulation materials have health risks, some so significant the materials are no longer allowed to be used but remain in use in some older buildings such as asbestos fibers and urea. Consideration of materials used Factors affecting the ty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PIR Board Fire Test
Pir or PIR may refer to: Places * Pir, Kerman, a village in Kerman Province, Iran * Pir, Satu Mare, commune in Satu Mare County, Romania Religion * Pir (Alevism), one of the 12 ranks of Imam in Alevism * Pir (Sufism), a Sufi teacher or spiritual leader * Pir (Zoroastrianism), pilgrimage site in Persia, typically Zoroastrian Science and technology * PIR (gene), for a human protein that is a possible transcriptional coregulator * Parrot intermediate representation, one of the two assembly languages for the Parrot virtual machine * Partners in Research, Canadian bio-medical research charity * Passive infrared sensor, detects infrared emission * Peak information rate, a burstable rate set on routers and switches that allow throughput overhead * Polyisocyanurate, a plastic used for thermal insulation * Private information retrieval, a protocol for retrieving data without revealing what was retrieved * Protein Information Resource, database and bioinformatics resource * Public Inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grenfell Tower Fire
On 14 June 2017, a high-rise fire broke out in the 24-storey Grenfell Tower block of flats in North Kensington, West London, at 00:54 BST and burned for 60 hours. 72 people died, two later in hospital, with more than 70 injured and 223 escaping. It was the deadliest structural fire in the United Kingdom since the 1988 ''Piper Alpha'' oil-platform disaster and the worst UK residential fire since World War II. The fire was started by an electrical fault in a refrigerator on the fourth floor. This spread rapidly up the building's exterior, bringing flame and smoke to all residential floors, accelerated by dangerously combustible aluminium composite cladding and external insulation, with an air gap between them enabling the stack effect. The fire was declared a major incident with more than 250 London Fire Brigade firefighters and 70 fire engines from stations across London involved in efforts to control the fire and rescue residents. More than 100 London Ambulance Service crews ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PIR Panels 02
Pir or PIR may refer to: Places * Pir, Kerman, a village in Kerman Province, Iran * Pir, Satu Mare, commune in Satu Mare County, Romania Religion * Pir (Alevism), one of the 12 ranks of Imam in Alevism * Pir (Sufism), a Sufi teacher or spiritual leader * Pir (Zoroastrianism), pilgrimage site in Persia, typically Zoroastrian Science and technology * PIR (gene), for a human protein that is a possible transcriptional coregulator * Parrot intermediate representation, one of the two assembly languages for the Parrot virtual machine * Partners in Research, Canadian bio-medical research charity * Passive infrared sensor, detects infrared emission * Peak information rate, a burstable rate set on routers and switches that allow throughput overhead * Polyisocyanurate, a plastic used for thermal insulation * Private information retrieval, a protocol for retrieving data without revealing what was retrieved * Protein Information Resource, database and bioinformatics resource * Public Inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyester
Polyester is a category of polymers that contain the ester functional group in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include naturally occurring chemicals, such as in plants and insects, as well as synthetics such as polybutyrate. Natural polyesters and a few synthetic ones are biodegradable, but most synthetic polyesters are not. Synthetic polyesters are used extensively in clothing. Polyester fibers are sometimes spun together with natural fibers to produce a cloth with blended properties. Cotton-polyester blends can be strong, wrinkle- and tear-resistant, and reduce shrinking. Synthetic fibers using polyester have high water, wind and environmental resistance compared to plant-derived fibers. They are less Fireproofing, fire-resistant and can melt when ignited. Liquid crystalline polyesters are among the first industrially used liquid crystal polymers. They are use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Building Envelope
A building envelope is the physical separator between the conditioned and unconditioned environment of a building including the resistance to air, water, heat, light, and noiseSyed, Asif. ''Advanced building technologies for sustainability''. Hoboken, N.J.: John Wiley & Sons, Inc., 2012. 115. Print. transfer. Discussion The building envelope (or the more modern term, building enclosure) is all of the elements of the outer shell that maintain a dry, heated, or cooled indoor environment and facilitate its climate control. Building envelope design is a specialized area of architectural and engineering practice that draws from all areas of building science and indoor climate control. The many functions of the building envelope can be separated into three categories:Straube, J.F., Burnett, E.F.P. ''Building Science for Building Enclosures''. Building Science Press, Westford, 2005. * Support (to resist and transfer structural and dynamic loads) * Control (the flow of matter and energy of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyurethanes
Polyurethane (; often abbreviated PUR and PU) 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, varnishes and coatings, adhesives, electrical potting compounds, and fibers such as spandex and PUL. Foams are the largest application accounting for 67% of all polyurethane produced in 2016. A polyurethane is typically produced by reacting an isocyanate with a polyol. Since a polyurethane contains two types of monomers, which polymerize one after the other, they are classed as alternating copolymers. Both the isocyanates and polyols used to make a polyurethane contain two or more functional groups per molecule. Global production in 2019 wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastics
Plastics are a wide range of synthetic polymers, synthetic or semi-synthetic materials that use polymers as a main ingredient. Their Plasticity (physics), plasticity makes it possible for plastics to be Injection moulding, moulded, Extrusion, extruded or Compression molding, pressed into solid objects of various shapes. This adaptability, plus a wide range of other properties, such as being lightweight, durable, flexible, and inexpensive to produce, has led to its widespread use. Plastics typically are made through human industrial systems. Most modern plastics are derived from petrochemical, fossil fuel-based chemicals like natural gas or petroleum; however, recent industrial methods use variants made from renewable materials, such as corn or cotton derivatives. 9.2 billion tonnes of plastic are estimated to have been made between 1950 and 2017. More than half this plastic has been produced since 2004. In 2020, 400 million tonnes of plastic were produced. If global trends on pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TheGuardian
''The Guardian'' is a British daily newspaper. It was founded in 1821 as ''The Manchester Guardian'', and changed its name in 1959. Along with its sister papers ''The Observer'' and ''The Guardian Weekly'', ''The Guardian'' is part of the Guardian Media Group, owned by the Scott Trust Limited, Scott Trust. The trust was created in 1936 to "secure the financial and editorial independence of ''The Guardian'' in perpetuity and to safeguard the journalistic freedom and liberal values of ''The Guardian'' free from commercial or political interference". The trust was converted into a limited company in 2008, with a constitution written so as to maintain for ''The Guardian'' the same protections as were built into the structure of the Scott Trust by its creators. Profits are reinvested in journalism rather than distributed to owners or shareholders. It is considered a newspaper of record in the UK. The editor-in-chief Katharine Viner succeeded Alan Rusbridger in 2015. Since 2018, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyurethane
Polyurethane (; often abbreviated PUR and PU) refers to a class of polymers composed of organic chemistry, 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 List of polyurethane applications, different applications. These include rigid and flexible foams, varnishes and coatings, adhesives, Potting (electronics), 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. A polyurethane is typically produced by reacting an isocyanate with a polyol. Since a polyurethane contains two types of monomers, which polymerize one after the other, they are classed as Copolymer#Alternating copolymers, alternating copolymers. Both the isocy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saint-Gobain
Compagnie de Saint-Gobain S.A. () is a French multinational corporation, founded in 1665 in Paris and headquartered on the outskirts of Paris, at La Défense and in Courbevoie. Originally a mirror manufacturer, it now also produces a variety of construction, high-performance, and other materials. History 1665-1789: Manufacture royale Since the middle of the 17th century, luxury products such as silk textiles, lace and mirrors were in high demand. In the 1660s, mirrors had become very popular among the upper classes of society: Italian cabinets, châteaux and ornate side tables and pier-tables were decorated with this expensive and luxurious product. At the time, however, the French were not known for mirror technology; instead, the Republic of Venice was known as the world leader in glass manufacturing, controlling a technical and commercial monopoly of the glass and mirror business. French minister of finance Olivier Bluche wanted France to become completely self-sufficient ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Cyanide
Hydrogen cyanide, sometimes called prussic acid, is a chemical compound with the formula HCN and structure . It is a colorless, extremely poisonous, and flammable liquid that boils slightly above room temperature, at . HCN is produced on an industrial scale and is a highly valued precursor to many chemical compounds ranging from polymers to pharmaceuticals. Large-scale applications are for the production of potassium cyanide and adiponitrile, used in mining and plastics, respectively. It is more toxic than solid cyanide compounds due to its volatile nature. Structure and general properties Hydrogen cyanide is a linear molecule, with a triple bond between carbon and nitrogen. The tautomer of HCN is HNC, hydrogen isocyanide. Hydrogen cyanide is weakly acidic with a p''K''a of 9.2. It partially ionizes in water solution to give the cyanide anion, CN−. A solution of hydrogen cyanide in water, represented as HCN, is called ''hydrocyanic acid''. The salts of the cyanide ani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
