Biodegradable mulch for agricultural applications

Abstract

Biodegradable mulch of the type used in various agricultural applications is made by multi-layer extrusion from a mixture of two compostable biodegradable polymers that comply with the EN13432 standard and that include potato starch, a black masterbatch and biodegradable recycled polymers. The mulch self-degrades in a short period of time, becoming a compostable material that enriches the soil, avoiding the collecting and cleaning tasks that are necessary in conventional mulches.

Claims

1. Biodegradable mulch for agricultural applications comprising: compostable biodegradable biopolymer A that complies with the EN13432 standard, that incorporates potato starch in a proportion of between 50 and 70% by weight of the end product and that has a particle size of between 1.5 and 2.4 mm, a molten density of between 1.1 and 1.2 g/cm3, a density of between 1.2 and 1.3 g/cm3, a bulk density of between 740 and 800 kg/m3, and a melt flow index MFI of between 2.5 and 5.5 g/10 min, at a temperature of 190 C. and with a weight of 5 kg on a piston, compostable biodegradable biopolymer B that complies with the EN13432 standard and that includes potato starch in a proportion of between 10 and 40% by weight of the end product, black masterbatch in a proportion of between 5 and 10% by weight of the end product, and biodegradable recycled polymers in a proportion of up to 30% by weight of the end product.

2. Biodegradable mulch for agricultural applications according to claim 1, wherein biopolymer B has a particle size of between 2 and 3 mm, a molten density of between 1.1 and 1.3 g/cm3, a density of between 1.2 and 1.4 g/cm3, a bulk density of between 880 and 940 kg/m3, and a melt flow index MFI of between 20 and 40 g/10 min, at a temperature of 190 C. and with a weight of 2.16 kg on a piston.

3. Biodegradable mulch for agricultural applications according to claim 1, wherein the mulch comprises a co-extrusioned multi-layer structure.

4. Biodegradable mulch for agricultural applications according to claim 3, wherein the multi-layer structure is a three-layer structure.

5. Biodegradable mulch for agricultural applications according to claim 1, wherein the total thickness of the mulch is 15 microns (+/8%).

6. Biodegradable mulch for agricultural applications comprising: compostable biodegradable biopolymer A that complies with the EN13432 standard, that incorporates potato starch in a proportion of between 50 and 70% by weight of the end product and that has a particle size of between 1.5 and 2.4 mm, a molten density of between 1.1 and 1.2 g/cm3, a density of between 1.2 and 1.3 g/cm3, a bulk density of between 740 and 800 kg/m3, and a melt flow index MFI of between 2.5 and 5.5 g/10 min, at a temperature of 190 C. and with a weight of 5 kg on a piston, compostable biodegradable biopolymer B that complies with the EN13432 standard and that includes potato starch in a proportion of between 10 and 40% by weight of the end product, black masterbatch in a proportion of between 5 and 10% by weight of the end product.

Description

PREFERRED EMBODIMENT OF THE INVENTION

(1) The biodegradable mulch for agricultural applications that is the object of the present invention basically comprises compostable biodegradable biopolymers A and B which comply with the EN13432 standard and that include potato starch, black masterbatch and biodegradable recycled polymers. The proportion of each of the elements is: biopolymer Abetween 50 and 70% by weight, biopolymer Bbetween 10 and 40% by weight, black masterbatchbetween 5 and 10% by weight, and biodegradable recycled polymersbetween 0 and 30% by weight

(2) All of the proportions refer to the end product.

(3) Biopolymer A has a particle size of between 1.5 and 2.4 mm, a molten density of between 1.1 and 1.2 g/cm.sup.3, a density of between 1.2 y 1.3 g/cm.sup.3, a bulk density of between 740 and 800 kg/m.sup.3, and a melt flow index MFI of between 2.5 and 5.5 g/10 min, at a temperature of 190 C. and with a weight of 5 kg on the piston.

(4) Biopolymer B has a particle size of between 2 and 3 mm, a molten density of between 1.1 and 1.3 g/cm.sup.3, a density of between 1.2 y 1.4 g/cm.sup.3, a bulk density of between 880 and 940 kg/m.sup.3, and a melt flow index MFI of between 20 and 40 g/10 min, at a temperature of 190 C. and with a weight of 2.16 kg on the piston.

(5) The biodegradable mulch for agricultural applications is manufactured by co-extrusion with a multi-layer, preferably, three-layer structure. Its total thickness is 15 microns (+/8%).

(6) Experimental tests performed have yielded the following mechanical characteristics for the mulch obtained, as can be seen in the table below:

(7) TABLE-US-00001 Impact (g) Dart test/Dart 180 test Opacity (%) 95% +/ 8% Mean max min Tear factor dm (mN) Machine direction 75.4 7.7 84.6 66.3 Tear factor dt (mN) Cross direction 277 20.5 287.2 246.2 Mean () Traction (N) Machine direction 9.64 0.36 Cross direction 5.81 0.34 Elongation (%) Machine direction 148.46 5.61 Cross direction 234.68 18.20 Perforation (N) 10.64 1.28