POLYLACTIDES - DEGRADABLE POLYMERS FOR FIBERS AND FILMS

Modification of a poly(L-lactide) (PLLA) base resin, by treatment with peroxides and compounding with plasticisers, yield resins which can b e processed by conventional techniques and equipment to thin blown fil ms, fibres and nonwoven fabrics having properties comparable to those of corresponding PP and PE samples. Film samples have tensile strength between 30 and 50 MPa, elongation at break around 250 %, and puncture resistance, measured as dart drop values, of 12 g/mu m. Fibres can be spun to filaments or directly to nonvowen fabrics by spun-bond techni ques. These fabrics have mechanical properties comparable to polypropy lene materials. The polymer products are readily degraded in a compost to carbon dioxide, water and biomass.