Polyolefins mulching films

Granular starch and copolymers of ethylene and acrylic esters and alkyl(meth)acr-ylates or vinylacetate are produced as master batches for the production of mulch films, geotextiles and molded articles.146 The polar copolymers act as compatibilizers by lowering the interfacial energy between starch and the polyolefin and eliminate the need to coat granules. Processing via a vented twin-screw extruder also eliminates the need for anhydrous starch. 

For the convenience of mulching the films are received from polyolefin introducing into the composition of photosensitive additives - iron and nickel dithiocarbamat or corresponding heroxides. With the purpose of acceleration biodecomposition of films on the basis of polythene for an agriculture, polypropylene pulp of cellulose is put into them [5]. 

Iron dithiocarbamate is an important additive for producing photodegrad-able polyolefins which have time-controlled decay of their mechanical properties [116,124,1917,1920]. Their potential uses range from very shortlived materials such as packaging which is required to degrade in the environment immediately it is discarded, through protective films for annual crops, where a lifetime of several months is required, to a protective mulch for young trees, which may be required to stand up to 3-4 years in exposed environments before embrittlement. 

---