LARIPURs are thermoplastic polyurethanes and consequently combine the working technology of thermoplastic products together with the we/l-known features of polyurethanes i.e.
- excellent abrasion resistance
- great flexibility and constancy at various temperatures
- good compression set resistance -good water and light resistance
- good resistance to oils, fats and many types of solvent.
Depending on their chemical nature LARIPURs can be grouped into several categories where the material formulations can be variously balanced to give the typical properties of polyurethanes as above.
LARIPURs covers a wide range of hardness from 60 Shore A to 75 Shore D. An important property of the LARIPURs products is the total absence of plasticizers. There are however plasticized grades available which are suitable for specific applications.
The raw materials used in the manufacture of LARIPUH are lsocyanates, chain extenders and polyols, which are reacted in carefully controlled conditions in order to ensure the highest possible quality and consistency of the end product. By varying the quantity of the components in the formulation of the polyurethane, it is possible to cover a wide range of applications giving different mechanical and chemical resistances.
The general characteristics of each Series are as follows:
SERIES 15 AND 18 PLASTICIZED ESTER
Products based on saturated polyester and containing a small amount of plasticizer, they have been specially developed to fill a gap between rubber materials and polyurethanes. They combine to give a very soft grade but with polyurethane 's typical features such as good flexibility and abrasion resistance, while maintaining short processing times. This can be particularly applied to the shoe industry where TPUs guarantee excellent adhesion to the two-component PU without applying any primer.
SERIES 20 STANDARD ESTER
Products based on standard grade saturated polyester. These show strong resilience and tear resistance, excellent abrasion resistance and good stability in water solvents, light and oxidation.
SERIES 25 SPECIAL ESTER
Products based on special grade saturated polyester. The features are similar to those of Series 20 but are characterised by a higher resistance to hydrolysis failure and improved flexibility at low temperatures.
SERIES 2102 POLYCAPROLACTONE ESTER
Products based on polycaprolactones. They behave roughly in the same way as TPU in the Special Ester Series but exhibit a higher resistance to hydrolysis failure.
SERIES 50 MODIFIELD ESTER
Products are obtained by homogenously incorporating small quantities of particular technopolymers in some rigid types belonging to the Special Ester Series. They couple their elevated hardness with an excellent cold impact resistance.
SERIES 60 AND 2103 ETHER
Products based on quality polyether. ln comparison with the Ester Series, they show a better resistance to hydrolysis and microbiological attack, a very good cold flexibility but a lower resistance to oxidation.
PRODUCTS FOR GASKETS
These are specially developed TPUs for manufacturing hydraulic gaskets or any other application where at high compression set, resistance to oils and/or high temperatures, is required. Two products based on polycaprolactone (2202-95A and 107- 93A) plus one based on Ether (2203-93A) belong to this group depending on the application.
These are homogenous mixtures of other techno polymers with TPU in a variable ratio, the characteristics of which can vary considerably dependent on the nature of the binder.
These grades cover the SEHIES 40 ESTEH specification for calendaring and soluble grades for the production of synthetic leather.
Other LARIPUR ranges are commercially available and are intended for special application.
These TPUs are available on demand according to the application.