PROPOSAL OF NEW ANALYTICAL METHODS OF WEA THERING OF ELASTOMERS AND APPLICATION TO OUTDOOR-EXPOSED STYRENE-BUTADIENE RUBBER

To investigate new analytical methods for weathering of elastomers, a styrene-butadiene rubber (SBR) for coloring use without carbon black w as analyzed by various analytical methods. The section analysis using a specific cutting force by the surface and interfacial cutting analys is system is applicable to degraded elastomers. The TMA method using c ompressive oscillating stress is effective for the measurements of the degraded elastomers with surface cracks whose viscoelastic properties are difficult to be measured by tensile or torsional methods. The fir st kind of correlation PAS gives information relating to thermal prope rties of the surface region of the elastomers degraded without color c hange. It was speculated that the formation of an oxidized thin layer suppressed internal degradation of outdoor-exposed samples in Miyakoji ma for longer than 1 year.