Interfacial tension between polymers

The use of the harmonic mean often leads to better predictions of interfacial tensions between polymers and better contact angles between liquids and polymer solids, but the criterion for maximization of the work of adhesion is the same as... 

Gramespacher H and Meissner J (1992) Interfacial tension between polymer melts measured by shear oscillations of their blends. J Rheol 36 1127-41. 

The surface dynamic changes, irrespective of starting points, occur in the direction to minimize the interfacial tension between polymer and the contacting medium. The overall change in the surface configuration can be viewed as the product of two major parameters, i.e., (1) polymer chain mobility and (2) driving force ... 

INTERFACIAL TENSION BETWEEN POLYMER SURFACE AND LIQUID WATER... 

Table 2.5 Interfacial Tensions between Polymer Melt Pairs Including Compatibilizing Agents. MAH-PP Maleic Anhydride Grafted Polypropylene SEES Hydrogenated Triblock Copolymer of Styrene and Butadiene MAH-g-SEBS Maleic Anhydride Grafted SEES PEMA-Zn Poly(ethylene-co-methacrylic Acid) lonomer Neutralized by Zinc.

Roe, R. J., Interfacial tension between polymer hquids, J. Colloid Interface Sci., 31, 228-235 (1969). 

The stability of the inverse latex strongly depends on an appropriate formulation. Poor chemical compatibility between oils and emulsifiers produces unstable latices, whereas a good chemical match leads to perfectly transparent and stable latices [17,18]. The latex stability was accounted for by (1) reduced gravity forces ( /, where d is the particle diameter) (2) high entropic contribution from the droplets owing to their large number and (3) low interfacial tension between polymer droplets and the continuous phase [4]. 

Tabulation of Typical Values of Interfacial Tensions between Polymers"... 

TABLE 18.6. Interfacial tension between polymers and carbon dioxide. 

Table 6,2 Values of interfacial tension between polymer-melt pairs.

Concerning microlatexes, particle dimensions are much smaller than those of conventional latexes. It follows that gravitational forces which tend to cause flocculation are considerably reduced (/g (f). The entropy contribution can therefore be decisive, given the large number of particles present. Furthermore, we can assume that interfacial tension between polymer droplets and the continuous medium is still very low, bearing in mind the extremely low values obtained in the initial microemulsions (7 10 dyne/cm). 

Since the interfacial tension between polymers is minor [17] and the adhesion of polymers to a filler differs essentially (Table 12.3), it may be supposed diat the filler localizing between polymer phases by the latter mechanism is most probable. The filler localization at the interface in all blends assigned to the first group according to Table 12.2 is likely to follow the last mentioned scheme. In those blends the local concentration of a filler at the interface is also governed by the equilibrium between the number of particles arriving at the interface and leaving it for a phase. 

From the above discussion it follows that with increasing difference in wetting forces of polymers the equilibrium concentration of CB at the interface must rise when a filler transfers to the interface from the phase of a lesser wetting force and must fall when it comes here from the phase of higher wetting force. Besides, the rise of interfacial tension between polymers must promote the increase in local concentration of CB at the interface when it is redistributed from any phase. 

Even small amounts of reaction have been found to greatly reduce the interfacial tension between polymers. Sundararaj [35] used the breaking thread method to measure... 

Considerations and measurements of interfacial tension between polymer melts dates to the 1960s and 1970s [54 to 57]. Several different methods have been used to measure interfacial tension. Extensive use has been made of 1) the shape of drops emerging from a capillary into a second phase (falling drop) [56 to 60] and 2) thread breakage, the breakup of stationary hlaments in a second liquid phase by a capillary instability [59 to 61 ]. The latter analysis is based on the work of Tomotika [62]. Other methods have been used. 

Table 5.6 Interfacial Tensions Between Polymer Melts Pairs [59]...

II. The degree of dispersion of the aystaUizable dispersed phase in here, factors such as blend composition, nanoparticle localization and dispersity, interfacial tension between polymer component, the melt viscosity of the components, mixing conditions, blend preparation, etc., are critical [92,93],... 

Roe R J (1969) Interfacial tension between polymer liquids. J Colloid Interface Sci 31 228 235... 

Fig. 10. (a) Interfacial tension between polymer-rich phase and solvent-rich phase as a function of pressure p at temperature kgT/e = 0.75 which corresponds to T = 314A . For p < jOtripie = 0.193174 F/cr the polymer-rich phase coexists with a solvent-vapor, while beyond the triple pressure it coexists with a solvent-rich liquid. The jump of the interfacial tension at the triple point is hardly visible on the scale of the figure. The insets show the logarithmic divergence of the interfacial excess as one approaches the triple pressure from below and the experimental values of the interfacial tension at T = 40 C= 313.15K. (b) Density profiles between coexisting phases at various pressures as indicated in the keys. From [164]... 

Additives can greatly reduce the interfacial tension between polymers and hence modify the mixing process and the properties of the blend. Block and graft copolymers are the most effective interfacial agents and can be added to the blend or formed during the mixing process by reactions between the base polymers. " There are theoretical treatments of the behavior of block copolymers at the polymer/polymer interface but comparable experimental data is scarce. 

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