Germany’s FSK foamed polymers association held its annual meeting in Bad Durkheim, and at BASF’s plant in Ludwigshafen, Germany. Simon Robinson visited the heart of Germany’s Rhineland-Palatinate wine growing region to report.
The FSK is a very broad church, and this was reflected at the meeting which covered papers on subjects as diverse as multifunctional surfaces made using expanded polypropylene foam and several papers on foams made from melamine resin. But the bulk of the presentations were about polyurethane foam in one form or another.
The polyurethane section started off with Frank Prissok of BASF, who explained how micro-cellular foams made of thermoplastic polyurethane are finding use in the Adidas Boost footwear technology.
Prissok said the material is very good at returning energy to runners. When the runner’s foot hits the ground, he explained, an “air cushioning effect makes the cells feel extremely soft at the first moment of compression. But it becomes increasingly stiffer as the stride continues. While jogging, it initially dampens and cushions the impact of the foot”.
The material at the heart of innovation, he said, is a butanediol chain-extended TPU, which is foamed into particles about 1 cm in diameter using a proprietary technique. The TPU can be tuned to give a hardness of between Shore A 45 and Shore D 85, Prissok…