N. Reuge et al., Elastomer biaxial characterization using bubble inflation technique. I: Experimental investigations, POLYM ENG S, 41(3), 2001, pp. 522-531
The biaxial rheological behavior of materials such as elastomers or polymer
s can be obtained using a bubble-inflation-technique. A circular membrane i
s clamped at the rim and expanded under gas pressure. The inflation of the
circular membrane is recorded using a CCD video camera and the blowing pres
sure by a pressure sensor. Then, from elongation and curvature radius measu
rements at the pole of the bubble, one can deduce equibiaxial stress-strain
data. This study describes the optimization of a bubble-inflation rheomete
r. The most sensitive point of the technique is the estimation of the elong
ation at the bubble pole, deduced from video camera measurements. A direct
measurement of the bubble thickness was performed using a magnetic probe in
order to validate rheometer results. Such a validation has evidently never
been carried out before. Results of quasi-static equibiaxial characterizat
ion of elastomers are presented and analyzed.