Specialty chemicals company Lanxess has developed a new range of methylene diphenyl diisocyanate (MDI) polyether prepolymers containing what it describes as renewable, bio-based raw materials.
The products, marketed under the brand name Adiprene Green, aim to replace existing fossil based polyether prepolymers, which are used to manufacture highly durable polyurethane (PU) elastomers.
The overall objective to develop Adiprene Green was to create a range of bio-based prepolymers which allow the PU processor to produce components with a reduced CO2 footprint. Depending on the system, a reduction of CO2 between 20 to 30% is possible compared to fossil-based prepolymers due to the use of polyether polyols based on starch.
The term prepolymer refers to a monomer or system of monomers that have been reacted to an intermediate molecular mass state. Basically, its a preliminary stage to producing the polymer. Polymers are chains of molecules which have been cross-linked in a chemical reaction. So, rubber and plastics goods are obtained from raw materials after a suitable cross-linking process. The polyurethanes materials are rubber-like and can be used for many applications like e.g. skater/roller wheels or industrial coatings.
The share of bio-based raw materials varies between 30 to 90% dependent on the targeted system hardness. At the same time the existing PU processing capabilities would remain applicable and the properties of the final polyurethane elastomer would be similar to established elastomers based on fossil based polyether or even better.
Dr. Markus Eckert, head of the Lanxess (@LANXESS) Urethane Systems business unit, said: “At Lanxess, we have a clear sustainability strategy. With the goal to be climate neutral until 2040, we are building on our established and successful commitment to climate protection. The first major projects have already been launched. By using our new Adiprene Green products, customers can benefit from our journey to climate neutrality.”
In a statement, Lanxess said: “Adiprene Green prepolymers are easy to handle – they are processed in an identical manner to conventional prepolymers. No modifications to material handling, process temperatures or mixing ratios are necessary. In addition, the reactivity profile and demolding times are similar to fossil-based polyether prepolymers.”
When reacted with 1,4 butanediol, a range of PU elastomers with a hardness from 40 Shore A to 60 Shore D can be achieved. As the PU system is versatile, Adiprene Green can be hand-mixed or machine mixed. Moreover, the prepolymers can be processed with Vibracat catalysts from Lanxess. Products of the Adiprene Green line are well suited for demanding applications such as roll covers, wheels, press sleeves or non-pneumatic tyres.