Swelling, differential

The anomalous increase of the water uptake observed in Fig. 10 when approaching equilibrium at 60 °C has been associated to the damage. The abrupt upturn of the sorption curve may be explained considering a possible crazing of the low crosslinked internodular matrix induced by the differential swelling stresses that can arise, at high water contents, between areas of different crosslinking density. 

Results from Differential Swelling Test of Various Rubber Blends... 

Figure 6. High molecular weight polyisobutylene in cis-poly butadiene. Differential swelling in styrene at —25°C. Blends cured 30 minutes at 300° F.

The system Cl-butyl-cis-polybutadiene has been studied in some detail because it was suitable for the developed differential swelling technique and because this system of blends vulcanized with zinc oxide, sulfur, and thiuram disulfide first revealed the presence of interfacial bonds. This curative system has the feature of a flat cure —i.e.y the two homophases are vulcanized rapidly, and the crosslinked density does not increase radically as vulcanization time is prolonged. This is observed in Table IV by swelling and extractable levels of a series of crosslinked networks cured at increasing times and swollen in a common solvent, cyclohexane. 

Adhesion analysis from this differential swelling is shown in Figure 14 wherein the descending pattern of the plots of 30 or 60-minute cure time indicates the presence of interfacial bonds. 

The principle that is the basis for bicomponent fibers usually is likened to that which underlies the bicomponent metal strips often used in temperature controllers. With the latter, differential-thermal expansion of the two joined components results in a bending of the thermal element. With fibers, moisture usually is the agent that acts upon the two side-by-side portions. Differential swelling or shrinkage causes the fiber to be brought into... 

Callan et al. (1971a,b) used the differential swelling technique (vide infra) for a ranking of the relative affinity of carbon black to various elastomers. 

Pekot, L. J Reeves, S.R 2003. Modeling the effects of matrix shrinkage and differential swelling on coalbed methane recovery and carbon sequestration. Proceedings of the 2003 International Coalbed Methane Symposium. University of Alabama, 0328. 

The method of differential swelling of thin section of blends of EPDM and HR was first utilized by Callan et al. [40a]. In blends with EPDM, the HR phase absorbs more solvent therefore, the HR domains are thinner and... 

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