Slow-release fertiliser contg. polymer compsn. - comprising fertiliser incorporated in thermoplastic polymeric filaments of high surface area

摘要

Fertilizer compsn. comprise an inert, synthetic, thermoplastic polymer in which is incorporated 10-80% w/w of =1 fertilizer, the compsn. having a surface area 1 m2/g. Compsns. exhibit prolonged-release characteristics a and contain a high proportion of fertilizer which is released regularly in hexane. Typically a soln. of polyethylene (100 g/litre) contg. urea (50 g/litre) was passed through a nozzle at 150 degrees C and 8.5 atm. into an expansion chamber at 300 kg/h to give a fibrous mass, surface area 4 m2/g, with a urea content of 45.2% w/w.