Compression moulding voids

Melissaris and co-workers [46] have studied various novel p-ethynyl-substituted rigid rod monomers by DSC, TG and TG-FTIR and identified the main decomposition products. Void-free neat resin mouldings were made by compression moulding the monomers followed by heating. 

Krook et al. associated the subsequent improvement of the barrier properties achieved by compression moulding the sample, to the combined effect of the increase in crystallinity as well as the small decrease in void content. 

The Waters system uses a plastic cartridge which is inserted into a device (the Z-module) that subjects the column to radial compression, ie pressure is applied along the radial axis of the column tube. The flexible wall of the column then moulds itself into the voids that are present in the wall regions of the column. This method is claimed to produce an improvement in the packed bed structure, better column performance and longer useful column life. 

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