1. Flow-induced crystallization of polypropylene STW progress, 21th of september 2011 Tim van Erp, Gerrit Peters

2. overview non-isothermal, multi-phase crystallization effects of cooling rate effects of pressure flow-induced (non-isothermal, multi-phase) crystallization experimental part modeling part; discussion on parameters processingpropertiesstructure

3. PVT apparatus A = Outer piston B = Inner rotating piston C = Sample D = Teflon sealing ring E = Cooling channels F = Cooling channels G = Thermocouples

4. processing protocol: FIC experiments Annealing 10 min @ 250°C Compressed air cooling @ ~1°C/s Isobaric mode Pressures: 100 – 500 – 900 – 1200 bar Short term shearing of t s = 1s Shear rates: 3 - 10 – 30 – 100 – 180 s -1 ∆T = T m (p) – T shear = 30 - 60°C

5. analysis PVT data normalized specific volume dimensionless transition temperature

6. analysis PVT data normalized specific volume dimensionless transition temperature Deborah number (‘strength of flow’) WLF Temperature shift Pressure shift Shear temperature

7. results ∆T = 30°C

8. results ∆T = 60°C

9. dimensionless transition temperature

10. from spherulitic morphology to oriented structures flow regimes under non-isothermal conditions

11. saturation in crystallization temperature flow regimes under non-isothermal conditions

12. overview non-isothermal, multi-phase crystallization effects of cooling rate effects of pressure flow-induced (non-isothermal, multi-phase) crystallization experimental part modeling part quiescent crystallization flow-induced crystallization

13. quiescent crystallization space filling Schneider rate equations Avrami equation nucleation density individual growth rate ‘number’ ‘radius’ ‘surface’ ‘undisturbed volume’ ‘real volume’

14. modeling flow effects on crystallization

15. flow-induced crystallization model total nucleation density (flow-induced) nucleation rate shish length (L) growth rate equations Avrami equation ‘length’ ‘surface’ ‘undisturbed volume’ ‘real volume’ for

16. flow-induced crystallization model total nucleation density (flow-induced) nucleation rate shish length (L) growth rate equations Avrami equation ‘length’ ‘surface’ ‘undisturbed volume’ ‘real volume’ for experimentmodel

17. flow-induced crystallization model total nucleation density (flow-induced) nucleation rate shish length (L) growth rate equations Avrami equation F. Custódio, PhD Thesis, 2008 very laborious and inaccurate work

18. FIC regimes total nucleation density (flow-induced) nucleation rate shish length (L) growth Avrami equation

19. Mismatch between experimental results and model in oriented regime prediction of FIC regimes

20. plane equation scaling parameter parameters g n and g l g n and g l arbitrary function of T and p? a T, a P rheological shift factors

21. critical stretch shish length (L) growth

22. critical stretch new definition for critical stretch criterium?

23. critical stretch new definition for critical stretch criterium?

24. Good agreement between experimental results and model prediction of FIC regimes

25. conclusions characterization of flow enhanced (point-like) nucleation regime over wide range of processing conditions characterization of FIC of oriented structures regime over wide range of processing conditions extended dilatometry (PVT) proven to be a powerfull tool in characterizing flow induced crystallization