摘要 |
Oriented gels aliened by controlled stretching during the gel's transition from a heated, extremely viscous, non melting, non flowing state and the cooled solid gel state produces strong gels which are found to have greater tensile strength than gels of the same rigidity which have not been stretched to a selected degree during its heating and cooling histories. Gels which are selectively stretched during its (non melt flowing) heated state and rapidly cooled by flowing air, cold liquid bath or in contact with a cool surface exhibit optical birefringence when viewed under plane-polarized light.
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