Lyngaae-Jprgensen

Figure 7.26. Concentration dependence of shear viscosity of PS/PMMA blends. Points are experimental [Lyngaae-Jprgensen, 1983], while the lines were computed from Equation 7.125.

Lyngaae-Jprgensen, J., in Multiphase Polymers Blends and lonomers, Utracki, L. A., and Weiss, R. A., Eds., 395 ACS Symposium Series, American Chemical Society, Washington, DC (1989). 

Spndergaard, K., Valenza, A., and Lyngaae-Jprgensen, J., Polym. Networks Blends, 2 159 (1992). 

Percolation HDPE/PS viscosity ratio dependence Lyngaae-Jprgensen Utracki, 1991... 

PS/PMMA steady state shear viscosity Lyngaae-Jprgensen, 1983... 

HOPE PP immiscible capillary Alle Lyngaae-Jprgensen, 1980 Alle et al., 1981... 

Figure 9.9. Deformability of PS drops in PMMA during steady-state shear flow at 180°C. The points are experimental, the line is to guide an eye [Lyngaae-Jprgensen et at., 1993],...

Rheometer Experimental and theoretical study of drop elongation in a steady-state flow, at constant shear stresses. Lyngaae-Jprgensen et al., 1991, 1993. 

Since the successful S-S thermodynamic theory assumes fee or hep packing with the coordination number z = 12, the most probable value of Pc is 0.120. However, if the cluster formation starts at Tc, from Tc/Tg=l/ 1 -pc)= 1.15 - 1.35, then pc = 0.13 to 0.26, which suggest fee hep or bcc packing. It is noteworthy that the hindered molecular dynamics at Tg occurs at the percolation threshold similar in magnitude to the values found for formation of percolative phase co-continuity in polymer blends (i.e., Pc = 0.15 to 0.21) [Lyngaae-Jprgensen and Utracki, 1991]. 

The model adopted, hairy clay platelets (HCPs), was formulated considering the reduction of molecular mobility near the clay platelet crystalline surface [Utracki and Lyngaae-Jprgensen, 2002]. The data show that polymer adsorbed from solution or melt on a crystalline solid forms a layer whose thickness is comparable to the radius of gyration, the macromolecules adsorb physically on a solid surface,... 

Utracki and Lyngaae-Jprgensen [2002] observed several common aspects of exfoliated CPNCs and liquid-crystal polymers (LCPs). Similar six-phase structures are predicted for CPNCs and observed in LCPs isotropic, nematic, smectic-A, columnar, house of cards, and crystal [Porter and Johnson, 1967 Balazs et al., 1999 Ginzburg et al., 2000]. These phases in CPNCs originate in a balance between the thermodynamic interactions, clay concentration, and platelets orientation, while in LCPs they depend mainly on temperature. Since it is more difficult on the one hand to prepare disk-shaped than rigid-rod molecules, and on the other to develop flow theory for LCPs with disk moieties, the number of publications on the latter systems is small [Ciferri, 1991]. 

Within the linear viscoelastic region the modified Krieger-Dougherty [1959] dependencies might be used [Utracki, 1988 Utracki and Lyngaae-Jprgensen, 2002] ... 

J. Lyngaae-Jprgensen, L.A. Utracki, Makromol. Chem. Macromol. Symp. 48/49, 189 (1991)... 

As in polymer blends, also in BC the phase transition is affected by flow. Theoretically it was predicted that homogeneous melt can be obtained at T < UCST, provided that the stress field exceeds the critical value for the phase demixing, CTj2 > 012, crit (Lyngaae-Jprgensen 1989). 

Lyngaae-Jprgensen et al. (1993) developed a predictive model of morphology variation during simple shear flow of diluted polymer blends. The model considers the balance between the rate of breakup and the rate of drop coalescence. It was assumed that (i) the viscosity and elasticity of the dispersed phase are significantly lower than those of the matrix, (ii) only the cylindrical, large drops (defined by the long and short semiaxes aj and a2) are able to break and form small drops, and... 

P.S. Allan, M.J. Bevis, in Proceedings of 5-th Annuai PPS Meeting, Kyoto, 11-14 April 1989 N. Alle, J. Lyngaae-Jprgensen, Rheol. Acta 19, 94, 104 (1980)... 

S0ndergaard, K., Lyngaae-Jprgensen, J. In Flow Induced Structure in Polymers Nakatani, A. I. Dadmun, M. D., Eds. ACS Symposium Series 597 American Chenucal Society Washington, DC, 1995 pp. 169-187. 

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