Thermoplastic starch/natural rubber polymer blends were prepared using directly natural latex and cornstarch. The blends were prepared in
an intensive batch mixer at 150 8C, with natural rubber content varying from 2.5 to 20%. The blends were characterised by mechanical
analysis (stress-strain) and by scanning electron microscopy. The results revealed a reduction in the modulus and in tensile strength,
becoming the blends less brittle than thermoplastic starch alone. Phase separation was observed in some compositions and was dependent on
rubber and on plasticiser content (glycerol). Increasing plasticiser content made possible the addition of higher amounts of rubber. The
addition of rubber was, however, limited by phase separation the appearance of which depended on the glycerol content. Scanning electron
microscopy showed a good dispersion of the natural rubber in the continuos phase of thermoplastic starch matrix.
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