Plastic films, agricultural applications

Keeping in mind the potential applications of biodegradable plastics in agricultural applications (i.e., mulching films), the characterisation of the degradation behaviour of the copolyesters in soil is currently of great interest. 

Espi E, Salmeron A, Fontecha A, Garcia Y, Real AI (2006) Plastic films for agricultural applications. J Plast Film Sheet 22 85-102. doi 10.1177/8756087906064220 Evans K (1991) Lethal temperatures for eggs of Globodera rostochiensis, determined by staining with New Blue R. Nematologica 37 225-229... 

Realistic uses for Degradable Plastics include those applications where materials are used outdoors for a limited time only and it is not economically desirable to collect the residual materials after use. Examples are agricultural mulch, films and cordage, twine, etc. Another application is that of packaging which is stored and used indoors and discarded outdoors, in other words litter for which manual collection is not practicable. 

Starch from surplus corn has been converted into a superabsorbent material known as SUPER SLURPER. This is being marketed under license by several companies for use in removing water from refined petroleum products and as an absorbent in bandages and diapers. Biodegradable plastic films of starch mixed with other polymers find application as mulches in agriculture and as a... 

Similar plants have been designed to clean and separate PCW that enters the closed-loop recycling system, hence materials from specific domains of application, e.g., automotive or agricultural. In the latter case, scrap plastics film, composed mostly of PE and PVC, is also shredded, washed, and segregated by the floatation method [Anonym., 1991]. 

Plastic films are produced for their use either in packaging (which are either for food or non food, or for industrial/agricultural) or non-packaging applications. 

Aluminum pigments did find wide application in plastic films for garbage bags, canvases, as heat reflectors and for agricultural applications. Because plastic films are inherently thin, aluminum pigments with only a relatively small average particle size in the range of 10 pm and below are applied. 

In summary, it is apparent tbat there are selective opportunities for environmentally degradable polymers and plastics. Notably for water-soluble polymers where recovery is unlikely. There are niche opportunities for plastics such as fast food wrappers, fast food utensils, where separation is avoided and the plastic is already in a food matrix that is suitable for biodegradation litter ocean dumping agricultural applications where recoveiy is unlikely and expensive for films and mulch and hygienic products. 

In addition to imparting special properties other than degradability to plastic films, such as providing scalability, and microwave heatability (mentioned earlier) E/CO has been examined in other applications. For instance, water-soluble agricultural chemicals at concentrations up to 90 per cent have been pelleted in E/CO, making possible their preferential release in the spring and summer [19]. 

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