Stretch Blow Moulding of Mineral Filled PET

Injection Stretch Blow mouldng is a two step processing that was designed and optimized mainly using unfilled PET resins. This study focuses on stretch blow moulding of a PET filled with a few percent of sub micronic mineral fillers. Based on DSC, DMA, tensile tests as well as blowing on prototype machine main effects of fillers are analysed. It is demonstrated that fillers increases crystallization kinetics resulting in a reduction of the processing range. Difference in strain hardening induced by fillers makes it necessary to adjust blowing temperature. However main effect occurs during heating phase. Temperature within the perform is much less homogeneous than in PET making thermal gradient totally different if heating protocole is kept unchanged. Once heating is controlled to reach to equivalent thermal gradients as for PET blowing is possible and rather equivalent to that of pure PET.