Polyurethanes to be modified with Micromorphs - a polymeric additive displaying interesting features in widespread applications (Paper No. 29)

摘要

Polyurethanes are widely used in rubber industry, TPU and thermoplastic industry. Indeed, these polymers are unique, as simply by exchanging the monomers or by adjusting the amount of a specific monomer in a given combination, the final properties of the finished material can be adjusted in a wide range. This system flexibility allows for manufacturing and application of diverse material like i.e. millable polyurethanes, cast polyurethane elastomers, TPU, PU, solid and PU sponge from a range of available monomers. Nevertheless, there are inherent disadvantages of these polymers, as well. While abrasion resistance clearly is an advantage of polyurethanes, insufficient hydrolytic stability is ranking high among their disadvantages. Micromorphs® are very small, stable, crosslinked, spherical particles, of around 100 nm. Since they are crosslinked they maintain their morphology when heated well above their glass transition temperature. Simply by changing the ratio of monomers during polymerization polar or non polar, rubber like or plastics like behaviour of this particles is achievable. Due to their chemical composition these particles are stable against hydrolysis and depending on the amount of hard or soft monomers they can i.e. increase or reduce elasticity or hardness or change the rheology. Since these particles maintain their geometrical stability even at high temperatures they can be worked into any organic matrix by dispersive mixing. establishing a very large contact surface towards matrix or filler additives, thus changing and improving material performance ranging from millable polyurethanes to cold cast polyurethane systems and to TPU's. These particles neither take up fillers nor are they fillers. This paper gives an overview on the effect of these particles in a variety of polyurethane matrices.