Crystallization flow-induced

In industrial processes such as injection molding, extrusion, fiber spinning, or film blowing, a polymer is subjected to a flow, shear, elongation, or mixed deformation modes. The crystallization occurs either during the flow [Pg.228]

Haudin et al. [21] described shear-induced crystallization, taking into account both spherulites and shish-kebabs. The shish-kebabs were modeled as cylinders with an infinite length. Potential nuclei disappeared by activation and absorption, and new ones were created by flow. The crystallization was described by a set of differential equations, which were solved numerically. [Pg.229]

Parameters describing crystallization were optimized using the genetic algorithm inverse method—a stochastic optimization method based on the mechanism of natural selection [52]. [Pg.230]

It has to be emphasized that the classic Avrami and Evans equations, and consequently the Nakamura approach, were derived by assuming random positions of nuclei in a material therefore, they do not apply strictly when there is a correlation between positions of nucleation sites. Such nucleation of spherulites is accounted for in the model developed originally for fiber-reinforced polymers [53], described in Chapter 13. [Pg.230]

Isothermal crystallization of a polymer is frequently characterized by the induction time and the crystallization half-time. The crystallization induction time is the time that elapses from the moment when the desired crystallization temperature is reached to the onset of crystallization, characterized by the formation of the first nuclei. The crystallization half-time is the time when relative crystallinity reaches 0.5. More detailed analyses of the isothermal crystallization are usually based on the Avrami-Evans theory. Equation (7.10) yields [Pg.230]

ABOUT THE PROPER CHOICE OF VARIABLES TO DESCRIBE FLOW-INDUCED CRYSTALLIZATION IN POLYMER MELTS... [Pg.315]

Keywords Flow induced crystallization, polymers melts, molecular based rheology, classi-... [Pg.315]

Zuidema, H., Peters, G.W.M. and Meijer, H.E.H. (2002) Development and validation of a recoverable strain based model for flow-induced crystallization of polymers, Macromol. Theory Simul. 10(5), 447-460... [Pg.320]

J. A. Kulkarni and A. N. Bens, Lattice-based Simulation of Chain Conformation in Semicrystalline Polymers with Application to Flow Induced Crystallization, J. Non-Newt. Fluid Meek, 82, 331-336 (1999). [Pg.856]

A. K. Doufas, A. J. McHugh, and C. Miller, Simulation of Melt Spinning Including Flow-induced Crystallization. Part I. Model Development and Predictions, J. Non-Newt. Fluid Meek, 92, 27-66 (2000). [Pg.856]

Miller RL (Ed), "Flow Induced Crystallization in Polymer Systems", Gordon and Breach, NewYork, 1977. [Pg.743]

Hay, J. A. in Flow-Induced Crystallization in Polymer Systems Miller, R. L., Ed. Gordon and Breach Science Publishers New York 1979 pp 69-98. [Pg.90]

Model including flow-induced crystallization in the blown film... [Pg.465]

H. Zuidema, Eindhoven, Technische Universiteit Eindhoven, 2000, ISBN 90-386-3021-2, Thesis, Flow Induced Crystallization of Polymers, Application to Injection Moulding, 126 pages. [Pg.295]

R. L. Miller (ed.). Flow induced crystallization of polymers (Midland Macromolecular Monographs, Vol. 6), Gordon and Breach, New York, 1979. [Pg.421]

J. K. Keum, Y. Mao, F. Zuo, B.S. Hsiao, Flow-induced crystallization precursor stmcture in high molecular weight isotactic polypropylene (HMW-iPP)/low molecular weight linear low density polyethylene (LMW-LLDPE) binary blends. Polymer 54, 1425-1431 (2013)... [Pg.150]

Black W.B Miller R.L(ed) FLOW-INDUCED CRYSTALLIZATION IN POLYMER SYSTEMS GORDON AND BREACH SCIENCE PUBLISHERS... [Pg.272]

In flow-induced crystallization of polymers, the occurrence of an intermediate mesophase before the onset of the crystallization itself has a profound influence on the process, which we shall consider in this section. As mentioned above, due to the non-thermodynamic nature of the processes involved we encounter a biphasic coexistence of a partially ordered mesophase and the... [Pg.101]

Fig. 24 Schematic pictures of flow-induced crystallization from the polymer melt (a) for the random coil model (b) using the folded-chain fringed-micellar grain model...

Gurra G, Titomanlio G, Meisel I, Grieve K, Kniep CS, Spiegel S (2002) Flow-induced Crystallization of Polymers. John Wiley Sons... [Pg.115]

L. Jarecki, A, Ziabicki Thermodynamically controlled crystal orientation in stressed polymers. In Flow-Induced Crystallization in Polymers, ed by R.L. Miller (Gordon Sc Breach, New York 1977) pp 319-330... [Pg.86]

Role of Chain Entanglement Network on Formation of Flow-Induced Crystallization Precursor Structure... [Pg.133]

B.S. Hsiao Role of Chain Entanglement Network on Formation of Flow-Induced Crystallization Precursor Structure, Lect. Notes Phys. 714, 133-149 (2007)... [Pg.133]

Current Opinions on Flow-Induced Crystallization Precursor Structures... [Pg.134]

Role of High Moleculcir Weight Species in Flow-Induced Crystallization... [Pg.138]

The rheo-SAXS study of the LMWPE/HMA PE blend has revealed several new insights into the molecular mechanism of shish-kebab formation at the initial stage of flow-induced crystallization. These insights can be summarized as follows. [Pg.142]

Figure 5.17. Relative crystallinity obtained from analysis of SAXS patterns for various sodium 2,2 -methylene bis-(4,6-di-tert-butylphenyl) phosphate/iPP blends during isothermal flow induced crystallization (T = 145"C) at different shear rates. [Adapted, by permission, from Patil, N Invigorito, C Gahleitner, M Rastogi, S, Polymer, 54,5883-91,2013.]...

Avrami exponent of flow induced crystallization is closely associated with the aspect ratio of nucleating agent. ... [Pg.205]

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