IT202100021239A1 - BIOCOMPOSTABLE COMPOSITION - Google Patents

Description

BIOCOMPOSTABLE COMPOSITION

DESCRIPTION

Technical sector

The present industrial invention relates to an innovative biocompostable composition for the production of objects, currently produced in plastic material which do not belong to the category of completely biodegradable and compostable. The innovative biocompostable material? suitable for multiple uses and ? in compliance with all ISO standards.

State of the art

The term biodegradable materials indicates those materials that can decompose due to the action of bacteria, fungi or other microorganisms. To be definable biodegradable, Directive 94/62/EC establishes that the product must decompose by 90% within six months. To instead be defined as compostable, for example, compostable plastic can? define itself as such, must disintegrate in less than three months and no longer be? visible.

Biocompostable plastic materials based on corn, wheat, tapioca or beet starch are known in the state of the art and are currently on the market, manufactured on an industrial scale and used, for example, for waste bags. The plastics obtained from these compressed fibers are completely biodegradable and can replace petroleum-derived plastics.

However, this use of starch-based materials can reduce the availability of foodstuffs, if produced from agricultural products such as corn or wheat. The land needed to grow the raw material for the "bio-based" plastics currently being produced around the world amounts to about 0.02% of the arable area. If, on the other hand, we based all of the current world production of fossil plastics on biomass as a raw material, the percentage would rise to 5%. AND? therefore the use of alternative raw materials is necessary, for example from waste and secondary flows of agriculture and/or food production.

Furthermore, ? otherwise? known to the state of the art the so-called ?bioplastic? which, according to the definition given by European Bioplastics (EUBIO), corresponds to a type of biodegradable, bio-based and biocompostable plastic. Pi? precisely:

- can? derive (partially or entirely) from biomass and not be biodegradable (for example: bio-PE, bio-PP, bio-PET)

- can? derive entirely from non-renewable raw materials and be biodegradable (for example: PBAT, PCL, PBS) - pu? derive (partially or entirely) from biomass and be biodegradable (for example: PLA, PHA, PHB, starch-based plastics)

According to the definition given by Assobioplastiche, by bioplastics we mean those materials and manufactured articles, whether they are derived from renewable sources or of fossil origin, which have the characteristic of being biodegradable and compostable.

However, the degradation of these bioplastics can require a period from six to twenty-four months or even more times? long, underground or in water, depending on the percentage of non-renewable raw materials used.

Furthermore, the concept of biodegradability / biocompostability? ? Often ? associated with the idea of a product that you can? easily dissolve in the environment by itself. Unfortunately not ? Still like this, some materials, even if biodegradable/biocompostable, still need specific treatments, otherwise they can still cause damage to the environment in the short and medium term. Due to misinformation, people use biodegradable materials less carefully thinking that they can't be harmful, when in fact they are not. they become equally polluting if they are not treated correctly.

There is therefore the need to obtain a biocompostable composition that can be decompose quickly and which, at the same time, can perform the same functions as normal plastic, but capable of causing minimal impact on the environment and food production.

Summary of the invention

Purpose of the found object of the present invention ? therefore that of providing an innovative biocompostable composition free from the aforementioned drawbacks and presenting innumerable advantages.

Through this biocompostable composition, characteristics of density, elasticity, tensile strength, deformation are obtained, very similar to those of conventional polymers of petrochemical plastics. At the same time, the compounds used are biodegradable and therefore decompose within a short time. Furthermore, the percentages of vegetable matter used are limited to guarantee sustainability. of the food industry.

Advantageously, the innovative biocompostable composition can perform the same functions as ordinary plastic. ? Is it possible to produce practically everything with this composition without the quality? is inferior, from simple and functional objects such as plastic bags and soda cans, up to products much more? complex.

Advantageously, the objects made with this biocompostable composition are less expensive to produce, because? they use natural materials available and do not require transformations with chemical substances. Furthermore, they do not require complicated processes for their treatment.

Advantageously, the innovative biocompostable composition? in granular form.

According to the present invention ? then described a biocompostable composition, having the characteristics set forth in the attached independent claim.

Further embodiments of the invention, preferred and/or particularly advantageous, are described according to the characteristics set forth in the attached dependent claims.

Brief description of the drawings

The found sar? described below by means of the following drawing tables, which are entirely exemplary and non-limiting:

- Fig.1 illustrates the biocompostable composition according to an embodiment of the present invention, as a granular compound,

- Fig.2 illustrates an image of the starting material for the biodegradability test? of the composition, according to the present invention,

- Fig. 3 illustrates an image of the degradability? of the material of Fig.2 at the end of such, according to the present invention.

Detailed description

The biocompostable composition object of the present invention comprises the following compounds: starch (for example, corn, potatoes and tapioca, etc.), glycerol, sorbitol, polybutylene adipate terephthalate (PBAT), polylactic acid (PLA) and calcium carbonate (CaCO3) . In particular, the weight percentages of each compound are included in the following percentage ranges:

- starch from 15% to 25%,

- glycerol from 10% to 20%,

- sorbitol from 1% to 6%,

- polybutylene adipate terephthalate from 22% to 30%, - polylactic acid from 5% to 15%,

- calcium carbonate from 20% to 28%.

In a preferred but non-limiting embodiment of the biocompostable composition, according to the present invention, the compounds are present exactly in the weight percentages:

- 20% starch,

- 16% glycerol,

- sorbitol from 3%,

- polybutylene adipate terephthalate 27%,

- 10% polylactic acid,

- 24% calcium carbonate.

As shown in Figure 1, according to one embodiment of the compound, this is in the form of granules 1.

Numerous tests have been carried out to verify compliance? of the requirements for plastic material recoverable through biodegradation under conditions of industrial composting. In particular, the tests were performed on a flexible film for packaging, with a thickness of 104 ? 14 µm, obtained from the granulate of the biocompostable composition object of the present invention.

The results relating to the quantification of the concentrations of heavy metals and fluorine of the sample are shown in table 1.

Table 1

The results show that the sample complies with the requirements of EN 13432 for all indicated parameters.

Also, the disintegration test procedure ? compliant with ISO 16929:2019 (quantitative sieving test) and ? considered sufficient for compliance? to the disintegration requirements (> 90% within 12 weeks, as defined in the EN13432 standard).

To perform this test, the inoculum is prepared as follows: - Fruit/vegetables (50%, consisting of 12% banana, 28% apple, 12% pear, 12% carrot, 24% potato, 12% leek);

- mature compost (5%);

- Rabbit feed pellets (30%);

- Filling material (wood bark) (15 %).

Separately, the compost and bark are sieved to five cm and the sieved material is mixed. Are the fruit and vegetables cut into smaller pieces? five cm small. The compost is stored at a refrigerated temperature (4 ? 1?C) for 1 month (maximum).

The results of the analyzes carried out for the characterization of the inoculum are presented in table 2.

Table 2

The test material? been prepared using the sample cos? how is it? for the disintegration test. The compost bins were:

- 2 for control (inoculum alone - vessels #1 and #2 in Figure 3 and Table 5)

- 2 for the disintegration of the test material (sample inoculum, vessels No. 11 and 12)

The quantity? of test material added in each container was 1% on the wet base of the sample (for disintegration) Each container ? been filled with the same amount? of inoculum in each container (30 kg). Actual weights of test material and disintegration inoculum are presented in Table 3.

Table 3

Carefully, the inoculum and test material were mixed, the containers were closed, and the test ? started in the incubation chamber at a controlled temperature.

The equipment ? made by:

- composting container made of non-biodegradable and heat-resistant plastic, 60 liter volume, hermetically sealed with holes for air inlet and outlet and temperature probe and equipped with a drainage system consisting of a drainage layer ( gravel) with a height of at least five cm from the bottom of the container,

- probes for measuring temperature,

- data logger for temperature,

- residual oxygen determination system with integrated temperature sensor: continuous analyzer with UV sensor,

- climatic chamber,

- various sieves (2 mm, 10 mm and 5 cm mesh),

- technical balance (maximum 100 kg),

- analytical scale,

- Dewar container (volume 1.5 L).

The disintegration test? was carried out in a darkened incubation chamber, with temperature monitoring data acquired of the temperature monitoring during the disintegration test inside the vessels.

The results have shown that the oxygen concentration in the exhaust air ? always higher than 10% in compliance? to the requirements of the ISO 16929:2019 standard. The pH values are above 5 (according to the best composting environment) for all samples. Finally, the moisture content? of the materials inside each vessel ? higher than 40% as recommended for a good composting process (and it is not necessary to add water).

The level of maturity? some white samples? checked using the "Rottegrad" scale. The "Rottegrad" scale is evaluated on a 1 cm sieved sample and the maximum temperature reached (T max) is recorded in a self-heating test carried out in a Dewar vessel (see Methods Book for the Analysis of Compost 3rd Ed. - Qualit? federal compost). The capacity? of self-heating of fresh compost in Dewar containers provides an estimate of the degree of maturity? of the compost. The results are shown in table 4.

Table 4

The homogenized material is taken from each sample reactor of the disintegration test. After cooling to room temperature, a sieving treatment is carried out first at 1 cm, breaking the agglomerates manually and then sieved at 2 mm. No residual material is detected. The degree of disintegration? of 100% and the content of volatile solids can not? be quantified.

The results obtained are shown in table 5.

Table 5

Even if at least one exemplary realization ? been presented in the summary description and in the detailed description, it should be understood that there are a large number of variations which fall within the scope of the invention. Furthermore, it must be understood that the embodiment or embodiments presented are only examples which are not intended to limit in any way the scope of protection of the invention or its application or configurations. Rather, the summary description and the detailed one provide the expert technician of the sector with a convenient guide for implementing at least one exemplary embodiment, it being clear that numerous variants can be made in the function and in the assembly of the elements described herein, without departing from the scope of protection of the invention as established by the attached claims and their technical-legal equivalents.

Claims (4)

1. Biocompostable composition characterized by the following compounds: starch, glycerol, sorbitol, polybutylene adipate terephthalate (PBAT), polylactic acid (PLA) and calcium carbonate (CaCO3). 2. Biocompostable composition according to claim 1, wherein the compounds are present in the following ranges of weight percentages: - starch from 15% to 25%, - glycerol from 10% to 20%, - sorbitol from 1% to 6%, - polybutylene adipate terephthalate from 22% to 30%, - polylactic acid from 5% to 15%, - calcium carbonate from 20% to 28%. 3. Biocompostable composition according to claim 1 or 2, wherein the compounds are present in exactly the following weight percentages: - 20% starch, - 16% glycerol, - sorbitol from 3%, - polybutylene adipate terephthalate 27%, - 10% polylactic acid, - 24% calcium carbonate. 4. Biocompostable composition according to one of the preceding claims, which is in the form of granules (1).