WO2020067859A1

WO2020067859A1 - Biodegradable paste for multiple uses and method for preparing same

Info

Publication number: WO2020067859A1
Application number: PCT/MX2018/000098
Authority: WO
Inventors: Ángel ARELLANO GUZMÁN; Óscar GÓMEZ CASTILLO
Original assignee: Corporativo Boro S.A. De C.V.
Priority date: 2018-09-25
Filing date: 2018-09-26
Publication date: 2020-04-02

Abstract

A mixture for a biodegradable paste comprising: recycled PVC powder, with a hardness scale greater than 80 "Shore A", as hardening agent for the mixture; powdered plant-based material, the particles of which have a size of between 800 and 841 micrometres, to give a wood-like appearance; a mixture of barium, cadmium and zinc, as stabilising agent; and a pigment. The biodegradable paste obtained using the aforementioned mixture, and the method for preparing same; and a flexible hose manufactured from said biodegradable paste, and the method for manufacturing same.

Description

BIODEGRADABLE PASTE FOR MULTIPLE USES AND THEIR METHOD OF

PREPARATION

TECHNICAL FIELD OF THE INVENTION

The present invention relates to the technical field of chemistry and the plastics industry, specifically with plastic pipes; because it refers to: a biodegradable paste for multiple uses; to a method of preparing said biodegradable paste; to a flexible pipe made with said biodegradable paste; and to the method for manufacturing said flexible pipe.

BACKGROUND OF THE INVENTION

Currently, the use of plastics, artificial polymers, etc., has been increasing, where such plastics, for the most part, are not degradable or require a long time for their degradation to occur. In order to counteract these drawbacks, they are also currently has started an era of production of degradable, biodegradable plastics, etc., in order to reduce pollution levels.

For example, patent document W02011 / 125008 (Al) is intended for an eco-friendly PVC plasticized compound and its use to make a flexible hose. Where said compound comprises, according to the weight of the formulation: 20 to 80% of a PVC matrix; 10 to 50% of a plasticizing agent; 0.1 to 5% of a stabilizing agent; 0.1 to 50% of at least one vegetable filling; 0 to 50% of at least one additive; and 0 to 40% of at least one elastomer compatible with the PVC matrix. Said plasticized compound obtained has a hardness (Shore A) of 60 to 90, according to UNI EN ISO 868. The vegetable filling can be fibers, granules and powder of: walnut, coconut, almond, hazelnut, wood, corn starch, rice, cork, abaca, agave, henequen, grass grass, pineapple, bamboo, banana, walnut betel, hemp, sunn hemp, coconut husk, java cotton, indian grass, broom, hibiscus, etc. The vegetable filler can be a waste vegetable. Said vegetable filler has a particle particle size of 50 to 800 microns, preferably 100 to 700 microns, more preferably 150 to 600 microns, and even more preferred 200 to 500 microns.

The stabilizing agent can be: Ca-Zn, Ba-Zn, organic substance, and tin; with Ca-Zn being preferred, including calcium stearate, zinc stearate and stearic acid. Among the additives, a colorant is included.

The flexible hose, according to document W02011 / 125008 (Al), comprises at least: a first layer that makes contact with the liquid to be transported, made with a first thermoplastic polymer, consisting of the plasticized compound according to document WG2011 / 125008 (Al). Said flexible hose may also comprise at least a second external layer that covers the first layer; and a fibrous layer is provided between said first and second layers.

As can be seen, the plasticizing compound of said document W02011 / 125008 (Al) requires a plasticizing agent (B); In addition, with the size of the particles of the vegetal dust there is no wood appearance.

Patent document US6011091 (B) proposes the use of stabilizing agents such as tin, lead and a mixture of metals: Barium, Cadmium and Zinc for the elaboration of a cellulosic compound containing: at least one cellulosic material present in an amount of 60 to 70%; at least one PVC resin present in an amount of 30 to 40%, which in turn comprises at least one stabilizer (2 to 8 parts per 100 parts of PVC}, a lubricant (4 to 10 parts), and at least one process assistant, and at least one heat sealing material. However, it does not disclose an embodiment of a stabilizer.

US6011091 (B) also describes a method for extruding the cellulosic compound from said document, the method comprises the following steps: extruding said cellulosic compound; and let the cellulosic compound cure, for a sufficient time and temperature to form an extruded solid. Where the PVC resin is obtained by combining 6 phr of stabilizer, 7 phr of lubricant, and 4 phr of process accelerator, and they are mixed at a temperature of 104.44 ° C; and cool to room temperature. Wood flour was dehydrated to less than 2% humidity. The PVC resin and wood flour were mixed on a mixing belt for 10 min. The first two stages of the extruder were heated to 193.33 ° C and the last two stages that occur after the vent were heated to 176.67 ° C. The screw temperature was 182.22 ° C. A vacuum was applied to the vent to remove moisture from the extruded article.

That is why, to counteract the aforementioned drawbacks, a biodegradable paste for multiple uses was developed, whose characteristic details are clearly shown in the following description, figures and examples, which are accompanied to illustrate some of its preferred embodiments, so Said description, figures and examples should be considered illustrative, but not limiting, to the scope of protection of the present invention, where:

Figure 1 is a flow chart of the method for making the biodegradable pulp for multiple uses, of the present invention.

Figure 2 is a flow chart of the method for manufacturing a hose, using the biodegradable paste of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention comprises, in the first instance, a mixture for a multipurpose biodegradable paste, which comprises: recycled PVC powder, with a hardness scale greater than 80 "Shore A", as an agent to give hardness to the mixture.

The biodegradable mixture of the present invention comprises plant material powder, whose particles have a size between 800 to 841 microns, with this particle size, the products made with said paste, acquire the appearance of wood. The plant material can be: wood from forest trees, such as conifers (preferably pine), agave fibers or bagasse, coconut fibers, among others.

The biodegradable mixture also comprises a mixture of Barium, Cadmium and Zinc, which acts as a stabilizing agent for the mixture; where Barium is in an amount of 51%, Cadmium in an amount of 41%, and Zinc in an amount of 8%. An example of this product is marketed under the name TS5610®. Finally, said mixture can also comprise a pigment to reaffirm some shade of

in the mix .

Without seeking to limit the scope of protection of the present invention, a preferred embodiment of the biodegradable mixture of the present invention is when the recycled PVC powder is in an amount of 80 to 85%; the plant material powder is in an amount of 13 to 15%; the mixture of Barium, Cadmium and Zinc) is in an amount of 1.5 to 2.5%; and the pigment is in an amount of 0 to 0.08%. This embodiment of the biodegradable mixture is for making a flexible pipe, such as a flexible hose. Therefore, products made from the biodegradable blend of the present invention are objects within the scope of the present invention. Therefore, these quantities may vary depending on the type of product to be manufactured.

A further object of the present invention is a method for preparing the biodegradable pasta for multiple uses, of the present invention, where said method comprises the following steps:

- remove residual moisture from the plant material, heated from 60 to 90 ° C, for approximately 30 min, in a mixing machine;

- add all the ingredients of the mixture previously written;

- heating the mixture, from 80 to 120 ° C, for approximately 30 min; where a semi-homogeneous mixture is obtained; Y ~ d ~

- pelletize the semi-homogeneous mixture in a pelletizing machine, in this case of use a Baussano brand pelletizing machine, passing through 13 temperature zones, where the range, from lowest to highest, is from 140 to 170 ° C, obtaining pellets of homogeneous biodegradable paste.

A further object of the present invention is a method for the manufacture of a flexible duct (hose), with the biodegradable paste of the present invention, the method may be an extrusion manufacturing method, where said method comprises the following steps:

- Remove the residual moisture from the pellets obtained in the previous method, heated up to 60 ° C for approximately 30 min, in a heating and mixing machine;

- homogenizing the biodegradable paste, of the present invention, using an extruder machine having a 50 mm diameter screw, preferably;

- forming the flexible duct body with an air flow, (first extrusion) at 140 to 170 ° C;

- subjecting the formed duct body to a first thermal shock, with water at a temperature of 15 to 20 ° C;

- applying a reinforcement on the external surface of the body of the duct, with a weaving / weaving machine, where said reinforcement is a fabric or mesh of polyester thread;

- passing the body of the duct with its reinforcement, to a second extrusion, so that said reinforcement is firmly incorporated into the body of the duct and a layer of the biodegradable paste of the present invention is applied to it; this is done with a larger 60mm machine 1

spindle diameter, preferably, and at the same temperature of 140 to 170 ° C; Y

- subject the duct with a second thermal shock with water at a temperature of 15 to 20 ° C,

With this method a flexible duct is obtained, which can be used for the conduction of liquid, gaseous and solid fluids. This type of flexible duct can be: a hose, a tube, a typhoon, a hose, etc. which are biodegradable and flexible, due to the material with which it is made.

Claims

1. A mixture for a biodegradable paste, characterized in that it comprises: i) recycled PVC powder, with a hardness scale greater than 80 "Shore A", as a hardness agent for the mixture;

ii) plant material powder, whose particles are between 800 to 841 microns in size, to give an appearance to wood; Y

i) a mixture of Barium, Cadmium and Zinc, as a stabilizing agent.

2. The mixture of the preceding claim of the plant material is selected from the following group: wood from forest trees, agave fibers or bagasse, coconut fibers, and / or a combination thereof.

3. The mixture of the preceding claim, where the wood of forest trees is coniferous.

4. The mixture according to the preceding claim, where the conifers are pines.

5. The mixture according to claim 1, wherein the stabilizing agent mixture comprises: Barium in an amount of 51%; Cadmium in an amount of 41%; and Zinc in an amount of 8%.

6. The mixture according to the preceding claims, where: i) recycled PVC powder, with a hardness scale greater than 80 "Shore D", is in an amount of 80 to 85%;

ii) the powder of vegetable origin, is in an amount of 13 to 15%; Y

iii) the mixture of Barium, Cadmium and Zinc, is in an amount of 1.5 to 2.5%.

The mixture of the previous claim, where: i) the recycled PVC powder, with a hardness scale greater than 80 "Shore A", is in an amount of 85

ii) the powder of vegetable origin, is in an amount of 13%; Y

iii) the mixture of Barium, Cadmium and Zinc, is in an amount of 1.92%.

8. The mixture, as claimed in claim 1, characterized in that it further comprises a pigment.

9. The mixture of the preceding claim, wherein the pigment is in an amount between 0 and up to 0.08%, with respect to the total weight of the mixture.

10. The mixture of the preceding claim, wherein the pigment is in an amount of 0.08%, with respect to the total weight of the mixture.

11. A biodegradable paste for multiple uses, characterized in that it comprises, the mixture according to any of the preceding claims.

12. A flexible duct, characterized in that it comprises the biodegradable paste of the preceding claim.

13. The duct of the preceding claim, wherein the duct is a flexible hose.

14. A method for preparing the biodegradable pasta for multiple uses, of claim 11, wherein said method is characterized in that it comprises: i) removing residual moisture from the vegetable powder, heated from 60 to 90 ° C, during 30 rain, in a mixing machine;

ii) mixing all the ingredients that make up the mixture of claims 1 to 10; iii) heating the mixture, between 80 to 120 ° C, for 60 min, where a semi-homogeneous mixture is obtained; and iv) pelletizing the semi-homogeneous mixture in a Baussano brand pelletizing machine, passing through 13 temperature zones, where the range, from lowest to highest, is from 140 to 170 ° C, obtaining a homogeneous melted paste.

A method for manufacturing the flexible duct of claims 12 and 13, which is an extrusion manufacturing method, wherein said method is characterized in that it comprises: i) removing residual moisture from the pellets obtained in the method of the preceding claim , heated up to 60 ° C for approximately 30 min, in a heating and mixing machine; -lili) homogenize the biodegradable paste of ± 3. Claim 11, using an extruder machine with a spindle;

iii) forming the flexible duct body with an air flow, (first extrusion) at 140 to 170 ° C;

iv) subjecting the formed duct body to a first thermal shock, with water at a temperature of 15 to L o.

v) applying a reinforcement on the external surface of the body of the duct, with a weaving / weaving machine, where said reinforcement is a fabric or mesh of polyester thread;

vi) passing the body of the duct with its reinforcement, to a second extrusion, so that said reinforcement is firmly incorporated into the body of the duct and a layer of the biodegradable paste of claim 11 is applied to it, with an extruder machine with us.il .Io larger than the screw of the extruder machine of stage ii); and from 140 to 170 ° C; and vii) subjecting the duct with a second thermal shock with water at a temperature of 15 to 20 ° C.