摘要 |
The invention relates to a process for making a compression spring member comprising the steps of making a preform from a copolyetherester composition; submitting the preform to at least one compression cycle, comprising the steps of applying a force to compress the preform in one direction to an extent greater than 30% of its original size and releasing the force from the compressed preform; wherein a copolyetherester composition is applied that comprises 1) at least 50 mass % of at least one copolyetherester consisting essentially of polyester hard segments that are built up from repeating units derived from at least one alkylene diol and at least one aromatic dicarboxylic acid and soft segments derived from a poly(propylene oxide)diol; and 2) 0.01-2 mass % of a nucleating agent. This process of making compression spring members shows better consistency and reproducibility. A further advantage is that an annealing step can be significantly reduced in time, or even be omitted. The invention further relates to a compression spring member obtainable by said process, and to a compression spring assembly comprising at least one such compression spring member.
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