A cryo-bulge apparatus for in situ weather balloon crystallization capturing during blowing by synchrotron radiation x-ray scattering

A cryo-bulge apparatus, which can be directly installed in the synchrotron radiation x-ray scattering beamline, is designed and manufactured. Using the cryo-bulge apparatus, the crystallization of natural rubber during blowing can be captured in situ. For mechanical measurements, the rubber film is tightly clamped at the periphery of a circular window. A low temperature measurement is achieved by the presence of a large iron block, which ensures low temperature variation ( 21 kPa. This suggests that the crystallization of rubber during blowing can occur under the equibiaxial deformation condition at low temperatures. The power scaling law is found to be 0.52%/kPa. The cryo-bulge apparatus is capable of clarifying the microstructural evolution of rubber during multi-dimensional deformation, which can provide guidance for the optimization of a weather balloon.