http://zh.wikipedia.org/zh-hk/% E8% 81% 9A% E6% B0% A8% E9% 85% AF polyurethane (English: Polyureth

http://zh.wikipedia.org/zh-hk/% E8% 81% 9A% E6% B0% A8% E9% 85% AF polyurethane (English: Polyurethane, abbreviated fun foam as PU) refers to the main chain containing carbamate characteristics of a class of polymer ester unit. Such polymer materials are widely used in adhesives, coatings, low-speed tires, washers, car mats and other industrial fields. fun foam In the areas of daily life are used to manufacture fun foam a variety fun foam of polyurethane foam and plastic foam. Also used in the manufacture of polyurethane condom (rubber condoms for people allergic to apply) and medical equipment fun foam research and development was originally polyurethane cooperation by the Otto Bayer and his colleagues in 1937 IG.Farben experiments fun foam in Leverkusen, Germany chamber begins. Their application by the addition polymerization of principle experiments, the use of liquid isocyanate and a liquid polyether or polyester glycol fun foam has been found to produce a polyolefin different from, and then condensed to form a new plastic --- polyurethane plastics. New polyester monomer mixture also from patent Wallace fun foam Carothers has been made. Initially, the application is limited to fibers and flexible foams. Followed by World War II affected their development (only a small range during the PU for air seats), until 1952 began isocyanates can be purchased fun foam commercially. 1954 started with toluene diisocyanate (TDI) and polyols for the production of flexible polyester polyurethane fun foam foam commercial FIG. This foam (initially called imitation Swiss cheese inventors) of the invention, thanks to which water was added to the reaction fun foam system, these materials are used in the production of rigid foams, adhesives and elastomers. Linear fibers are from hexamethylene diisocyanate (HDI) and 1,4 - butanediol, the reaction (BDO) of. The first commercial production of polyether polyols, poly (tetramethylene ether) glycol by polymerization of tetrahydrofuran Dupont in 1956. 1967, a urethane-modified polyisocyanate produced by rigid foam, the low-density insulation material produced exhibits better thermal stability and flame retardancy. Also in the 1960s, automotive interior safety components such as dashboards and door panels started using semi-rigid thermoplastic foam filling. From the early 1980s, pore water blown flexible polyurethane foam gasket models are used in automotive and tire sealing panel air filter. Since then, rising energy prices, and reduced requirements for use in automotive PVC growing polyurethane market fun foam share is increasing. Due to the expensive prices of raw materials to reduce the weight member, such as a metal cap and the filter housing and the reduction is compensated. fun foam Polyurethane elastomers and polyurethane foam filled high unfilled hot oil is now being used to filter them. Production of polyurethane foams (including foam rubber), the small amount to be added to the reaction mixture of volatile substances, called bubbling agent. These simple polyurethane material gives excellent insulation properties. The early 1990s, in order to reduce the impact on the ozone layer, the Montreal fun foam Protocol to limit the use of part of the chlorine bubbling agents. Such as trichlorofluoromethane (CFC-11). Other alkyl halides, such as chlorofluorocarbons, 1,1 - dichloro-1 - difluoroethane (HCFC-141b) were classified as greenhouse gases in 1994 IPPC Directive and the 1997 EU Gas Directive volatile organic substances being phased out . By the late 1990s, although there are some developing countries the use of halogen-containing blowing agents, North America and Europe has been increasing use of carbon dioxide, pentane, 1,1,1,2 - tetrafluoroethane (HFC-134a ), 1,1,1,3,3 - pentafluoropropane (HFC-245fa) as blowing agents. Based on existing technology and polyether polyurethane spray ammonia chemical theory, spray polyurethane elastic material has been rapid development in the 1990s. Their quick response and is relatively insensitive to moisture makes them the preferred characteristics of the paint coating of large projects. As a secondary safety enclosure, manholes and channel coatings, tank lining. After proper primer and surface treatment of concrete and steel has good adhesion. In the same period, a new two-component polyurethane polyurea and polyurethane elastomer blends technology has been applied to the construction site of the load bed liner Such small trucks and other transport cargo tank coating technology to create a durable, resistant to metal composite fun foam friction material. Thermoplastic metal lined make up deficiencies in areas prone to corrosion and brittleness. January 9, 2010 4:27 PM
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