Polyurethane casting resins - individual casting compounds
Polyurethanes (also shortened to PUR or PU) are plastics or synthetic resins. Polyurethanes are usually used as 2-component materials consisting of resin and hardener. They can be formulated and used both as compact materials (open-cell or closed-cell) and in the form of foams.
Compact materials are primarily used to protect components in the electronics industry.
We are your experts for customized casting resin systems and can produce compounds with product properties ranging from hard to soft, from tough to brittle, from low viscosity to high viscosity/ sagg resistant, from very fast to slow curing, from hydrophilic to hydrophobic. It is also possible to incorporate special properties such as flame retardancy, thermal conduction or thermal insulation, compressibility and many more.
Product overview – Polyurethane cast resins
Below you will find a selection of our polyurethane casting resins. Many other modifications are possible on request. Clicking on the product name will take you to the corresponding product page including all data sheets.
Product
Mixing ratio
resin : hardener
Mixed viscositiy (25°C; rot.; 1 s-1)
Hardeness
Downloads
Abb. 1 Aufbau eines nicht quervernetzten Polyurethans
We all use products containing polyurethane on daily basis. A large number of chemical raw materials, additives, fillers and other aggregates make it possible to realize a wide range of application profiles. PU cast resins can be found in the furniture industry in the form of mattresses or upholstery, as well as in vehicle interiors. They are also indispensable in the shoe industry, especially in shoe soles. In the building materials sector, polyethane casting resins can be found in a wide variety of applications, either in floor coatings or in insulation and assembly foams. In all industries the use of polyurethane protective coatings represents a very broad and elementary field of application.
Chemically, polyurethanes are made up of polyols and isocyanates (Fig. 1), whereby polymers with varying degrees of cross-linking are generally sought. In contrast to hotmelt adhesives, these are not thermoplastic. A large number of industrial polyols (polyether, polyester, polybutadiene, etc.) and isocyanates are available for the production of polyurethanes, allowing a wide variety of products and properties to be customized, so to speak.
Abb. 2 Wasser - Isocyanatreaktion
Another important chemical reaction of the isocyanate group is its reaction with water, which releases carbon dioxide and an amine. For this reason, when casting polyurethanes, especially for solid components, care must be taken to work under moisture free conditions as far as possible in order to achieve an optimum, bubble-free result. The addition of water-adsorbing fillers, so-called zeolites, can absorb residual moisture from the raw materials used, which makes application easier.
CO2 formation is used specifically in the formation of foams (insulation foams, mattresses, shoe soles) and pre-existing bubbles reinforce this effect further.
Through the formation of amines, NCO-terminated prepolymers can also cure with atmospheric moisture, making 1-component systems for sealants and adhesives possible.