PU

of PU (PU, DIN - abbreviations: ) Plastics or synthetic resins , which develop from the polyaddition reaction of a polyester or (Poly, are PURE) a Acrylates and a polyisocyanate. Of PU those is characteristic urethane - group.

<math> - NH-CO-o </math>

PU can, depending upon production hardand inflexibly, in addition, softly and flexibly its. In up-foamed form PURE is well-known as foam rubber or as building foam.

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history

1937 synthesized Otto Bavarian as well as his team in the laboratories the Bavarian AG in Leverkusen for the first time PU. 1940 began the industrielle production by the Bavarian works in Leverkusen. Due to the Second World War and the associated scarceness at raw materials the market developedfor PU however first only very slowly. So 1952 less than 100 t per year of the important polyisocyanate Toluylendiisocyanat ( TDI) were available. Polyester foam materials were developed from 1952 to 1954, whereby the commercial interest in PU was continued to increase. With the use of Polyetherpolyolen, also Polyole mentioned, increased the meaning of the PU rapidly. The larger variation options with the production of Polyetherpolyolen led to a substantial expansion of applications. Thus already 1960 over 45000 t at foam materials were produced.

Further technical improvements opened new application fields again and again. Thus made possiblethe introduction of propellants and the use of Diphenylmethan-4,4' (MDI) the production of polyurethane hard foams diisocyanat. In the last years with the prohibition by FCKW - haltigen propellants a turn in the production of these hard foams was introduced. Lately therefore it strengthens pentanes, dichloromethane or pure Carbon dioxide as propellants uses. Their outstanding isolating effect was not exceeded until today.

Up to the year 2002 world-wide consumption had risen to approximately 9 million tons at PU.

characteristics

of PU can do completely different depending upon choice of isocyanate and the alcoholCharacteristics exhibit.

allergies

can release and stand toxicity of isocyanates in the suspicion to cause cancer. TDI's evaporate at ambient temperature and can cause damage in the lung. The amines in the polyole are not likewise the health favorable. Generally are out-reacted mixtures for thatHumans however completely harmless.

In addition in polyurethane-coated clothes, for example rain clothes for children, poisonous materials were proven like tin-organic connections, which can arrive by the skin into the body.

use

from PURE mattresses , soles , seals , floors , lacquers become, Adhesives, sealing materials, skis, car seats, careers in stages, instrument panels, sealing compounds and much more besides manufactured.

  • PU becomes in the building industry as 1 - or 2-components foam (assembly foam) sealing joints in the concrete before pouring, the stabilization of foundations, the raisingof building parts, floors etc. used and with the installation of windows and doors uses.
  • Polyurethane rigid foam is used as isolating and insulating layer in sandwich elements. The elements consist of an internal and outside sheet metal (aluminum or coated steel sheet), whereby the gap is filled out by the swelling PU-foam. Predominantlythese sandwich elements are used in the industrial building when system resounding, since they are prefabricated and also fast to be installed to be able. Thus develop within a short time winding, roof structures, which are finished immediately dammed and inside, outside. Also with dammed roll and Schiebetoren (garage gates) Sandwichelemete are blocked.
  • PU elastomerfrequently for textile fibers one uses. These fibers do not consist necessarily to 100% of PURE. Likewise PU is used as micro foam for breathe-active diaphragm for rain clothing.
  • Due to the outstanding mechanical characteristics are suitable certain PU for applications, which require a high abrasion resistance. So z. B. withTransport of bulk materials by PU hoses, or as protective layer in pipes and tube bends.
  • A further more special industrial processing spectrum is in prototypes - and building of samples as well as in the foundry industry. Here products of PU are used, in order to manufacture models and tools many kind, in addition, production items.
  • During the production of multi-fallen tennis strings PU is used as filler.
  • Modern footballs (e.g. Roteiro) are manufactured completely from PU.

of

PU of PU [work on] is the employment in lacquers. Here becomesAs priming because of his good adhesion characteristics uses PURELY in particular.

In addition there is a variant as Coil Coating of lacquers and in the medicine as liner in the Prothetik of the lower extremities.

sealing compounds

  • PU-vacuum of casting resins: Different products with short pot life usually for prototypesor pilot lots, e.g. Series materials (thermoplastic - injection moulding: ABS, PP, POM, HP, PC, PMMA etc.) resembling mechanical and thermal specifications or optical aspects correspond. They are processed in a vacuum casting plant. Forms i.d.R. from polyaddition-interlacing silicone. Keyword: Duplicatingof parts manufactured with RWS ID prototyping - techniques.
  • PU-Schnellgiessharze: products for pouring hurry, models and tools, which can be processed relatively simply, which possess a short pot life and not under vacuum must be processed.
  • Elastomer hardening PU-casting resins: Products with different degrees of hardness settled in the shore A - range. For flexible to hard reading tables parts,Forms and tools.

RIM

RIM (Reaction Injection Moulding) are very reactive PU-resins, which are processed by means of low pressure injection moulding. Here will the resin components only briefly before it into the form are pressed, in a mixing head advancable to the form with one another mixed. Application for thin-walledParts such as prototypes, pilot lot parts and production items like e.g. Linings as well as parts within the vehicle range such as bumper, spoiler, inside panelings, housing etc.

foam materials

from PURE can be manufactured very simply foams. These are as foam rubber are admitting and become as cleaning sponge, mattress, cushion howeveralso to the isolation used in buildings and coolers.

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Trade name

see also

 

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