A method for treating waste from a natural latex production line

Abstract

The present invention relates to a method for treating waste materials of a natural latex production line, comprising the following steps: S1: crushing sponge waste materials with a crusher, and grading the crushed materials with a screen; S2: preparing a sponge fine material dispersion liquid by mixing 30-60 parts by weight of sponge crushed materials, 1-5 parts by weight of a wetting agent, 1-2 parts by weight of a dispersant, and 40-70 parts by weight of water; S3: adding the sponge fine material dispersion liquid to latex through a foaming machine for foaming, and producing. The present invention processes the sponge scraps and applies them to the production of latex sponges in the form of fillers, and can recycle the sponge waste materials generated in the production of latex sponge products, which is economical and environmentally friendly, and has high economic benefits.

Description

Technical Field

[0001] The invention relates to the technical field of latex product production, and in particular to a method for treating waste from a natural latex production line. Background Art

[0002] The main process steps of natural latex sponge production include: mixing → maturation → foaming → vulcanization → demoulding → washing → drying → cutting → packaging. In the foaming injection molding process, in order to ensure that the mold is fully filled, some foam latex will overflow from the air vents on the mold. At the same time, a lot of sponges will be cut out during the cutting process. For these sponges, some manufacturers deal with solid waste, and some manufacturers make scrap fillers. In recent years, the output of natural latex foam sponge products has increased significantly, and the waste in production has also increased. These two traditional treatment methods have certain limitations in terms of economic cost and environmental protection.

[0003] Therefore, exploring the treatment and recycling of production line waste has certain economic and social value. Summary of the invention

[0004] The purpose of the present invention is to provide a method for treating waste from a natural latex production line. The method treats the sponge scraps and applies them to latex sponge production in the form of fillers, and can recycle the sponge scraps generated in the production of latex sponge products, which is economical, environmentally friendly, and has high economic benefits.

[0005] A method for treating waste from a natural latex production line comprises the following steps:

[0006] S1: crush the sponge waste by a crusher and classify the crushed materials by a screen;

[0007] S2: 30-60 parts by weight of sponge crushed material, 0.3-0.8 parts by weight of wetting agent, 1-4 parts by weight of dispersant and 40-70 parts by weight of water are prepared into a sponge fine material dispersion;

[0008] S3: Add the sponge fine material dispersion into the latex through a foaming machine for foaming and production.

[0009] As a preferred embodiment, the sponge waste in S1 is washed and dried before crushing, the moisture content of the material before crushing is less than 2%, and the particle size after crushing is controlled at 10-20 μm. Latex crumbs with too small particle size are easy to agglomerate in the dispersion and are difficult to disperse.

[0010] As a preferred embodiment, the wetting agent is polyoxyethylene sorbitan monolaurate.

[0011] As a preferred embodiment, the dispersant is sodium methylenebis(vinylpyrrolidone)sulfonate.

[0012] As a preferred embodiment, the pH of the sponge fine material dispersion is controlled between 9-10.

[0013] As a preferred embodiment, the fine material dispersion addition process described in S3 is: the fine material is pumped into the delivery channel at the head of the foaming machine with a diaphragm pump. To ensure uniform dispersion of the fine material in the latex, the diaphragm pump is arranged at the front end of the zinc oxide and hardener input pumps, that is, to ensure that the fine material is added to the latex earlier than the zinc oxide hardener, so that there is sufficient dispersion time.

[0014] As another object of the present invention, the present invention also provides a method for preparing a latex sponge product using the above-mentioned sponge waste, comprising the following steps:

[0015] (1) The ingredients are prepared by an automated batching system: 90-110 kg of natural latex, 0.1-0.3 kg of potassium pyrophosphate, 4-8 kg of sulfur dispersion, 4-8 kg of potassium oleate, and 1-2 kg of potassium ricinoleate. The ingredients are added to a aging reactor for high-speed dispersion, mixing, and aging. The aging temperature is strictly controlled to be 35° C. to ensure that the dispersions are fully mixed and the aging reaction occurs at the set temperature. The pH of the entire aging system is adjusted to 9-10 and the viscosity to 800-1000 mPa.s.

[0016] (2) When the ripening time is 12 hours, the ripened latex is transported to a foaming machine for foaming, the rotation speed of the foaming disk is 500-700 r / min, and the ripened latex flow rate is 550-650 g / min;

[0017] (3) introducing sponge fine material dispersion, zinc oxide and hardener at flow rates of 60-80 g / min, 36 g / min and 30 g / min respectively;

[0018] (4) directly filling the foamed latex into the mold and vulcanizing it through a steam vulcanization device at a temperature of 100-110° C. for 25-35 minutes;

[0019] (5) Rinse the vulcanized product with water, dry it, and cut it.

[0020] The beneficial effects produced by the present invention are:

[0021] The invention processes the sponge scraps and applies them to the latex sponge production in the form of fillers, which is economical and environmentally friendly. The prepared product has similar performance to the natural latex sponge product without additions and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the products prepared in Example 1 and Example 4. DETAILED DESCRIPTION

[0023] In the following examples, the product density is tested according to the standard of GB / T 6343-2009 "Determination of apparent density of foamed plastics and rubber)".

[0024] The 40% indentation hardness is tested according to the standard GB / T 10807-2006 “Determination of hardness of soft foam polymeric materials (indentation method)”.

[0025] The tensile strength is tested according to the standard GB / T 6344-2008 “Determination of tensile strength and elongation at break of flexible foam polymeric materials”.

[0026] The rebound performance is tested according to the standard GB / T 6670-2008 "Determination of the rebound performance of soft foam polymer materials by the falling ball method".

[0027] The compression set performance is tested in accordance with the standard GB / T 6669-2008 “Determination of compression set of soft foam polymer materials”.

[0028] Example 1

[0029] This embodiment provides a method for preparing a latex sponge product, comprising the following steps:

[0030] (1) Using an automated batching system to prepare ingredients: 100 kg of natural latex, 0.2 kg of potassium pyrophosphate, 6 kg of sulfur dispersion, 4 kg of potassium oleate, and 1.5 kg of potassium ricinoleate are added to a aging reactor for high-speed dispersion, mixing, and aging. The aging temperature is strictly controlled to be 35° C. to ensure that each dispersion is fully mixed and undergoes a aging reaction at the set temperature. The pH of the entire aging system is adjusted to 9.8 and the viscosity to 800-1000 mPa.s.

[0031] (2) When the ripening time is 12 hours, the ripened latex is transported to the foaming machine for foaming. At this time, the rotation speed of the foaming disk is 600r / min, and the ripened latex flow rate is 600g / min.

[0032] (3) Zinc oxide and hardener are introduced at flow rates of 36 g / min and 30 g / min, respectively.

[0033] (4) The foamed latex is directly filled into the mold and vulcanized by a steam vulcanization device at a temperature of 100°C for 30 minutes.

[0034] (5) Rinse the vulcanized product with water, dry it, cut samples and test them.

[0035] The sample properties in Example 1 are as follows: density is 85kg / m 3, 40% indentation hardness is 80N, tensile strength is 85kPa, ball drop resilience is 64%, and compression permanent deformation rate is 9%.

[0036] Example 2

[0037] This embodiment provides a method for preparing a latex sponge product, comprising the following steps:

[0038] (1) Using an automated batching system to prepare ingredients: 100 kg of natural latex, 0.2 kg of potassium pyrophosphate, 6 kg of sulfur dispersion, 4 kg of potassium oleate, and 1.5 kg of potassium ricinoleate are added to a aging reactor for high-speed dispersion, mixing, and aging. The aging temperature is strictly controlled to be 35° C. to ensure that each dispersion is fully mixed and a aging reaction occurs at the set temperature. The pH of the entire aging system is adjusted to 9.8 and the viscosity is 800-1000 mPa.s.

[0039] (2) When the ripening time is 12 hours, the ripened latex is transported to the foaming machine for foaming. At this time, the rotation speed of the foaming disk is 600r / min, and the ripened latex flow rate is 600g / min.

[0040] (3) Sponge fine material dispersion, zinc oxide and hardener are introduced at flow rates of 60 g / min, 36 g / min and 30 g / min respectively.

[0041] (4) The foamed latex is directly filled into the mold and vulcanized by a steam vulcanization device at a temperature of 100°C for 30 minutes.

[0042] (5) Rinse the vulcanized product with water, dry it, cut samples and test them.

[0043] The sponge fine material dispersion is prepared by the following steps:

[0044] S1: The sponge waste is cleaned and dried before crushing. The moisture content of the material before crushing is 1.5%, and the particle size after crushing is 20 μm.

[0045] S2: 40 parts by weight of sponge crushed material, 0.5 parts by weight of polyoxyethylene sorbitan monolaurate, 2 parts by weight of sodium methylenebis(vinyl)sulfonate and 58 parts by weight of water are prepared into a sponge fine material dispersion liquid. The pH of the sponge fine material dispersion liquid is 9.8±0.1.

[0046] The sample properties in Example 2 are as follows: density is 90kg / m 3 , 40% indentation hardness is 90N, tensile strength is 65kPa, ball drop resilience is 55%, and compression permanent deformation rate is 15%.

[0047] Example 3

[0048] This embodiment provides a method for preparing a latex sponge product, comprising the following steps:

[0049] (1) Using an automated batching system to prepare ingredients: 100 kg of natural latex, 0.2 kg of potassium pyrophosphate, 6 kg of sulfur dispersion, 4 kg of potassium oleate, and 1.5 kg of potassium ricinoleate are added to a aging reactor for high-speed dispersion, mixing, and aging. The aging temperature is strictly controlled to be 35° C. to ensure that each dispersion is fully mixed and a aging reaction occurs at the set temperature. The pH of the entire aging system is adjusted to 9.8 and the viscosity to 800-1000 mPa.s.

[0050] (2) When the ripening time is 12 hours, the ripened latex is transported to the foaming machine for foaming. At this time, the rotation speed of the foaming disk is 600r / min, and the ripened latex flow rate is 600g / min.

[0051] (3) Waste rubber fine material, zinc oxide and hardener are introduced at flow rates of 70 g / min, 36 g / min and 30 g / min respectively.

[0052] (4) The foamed latex is directly filled into the mold and vulcanized by a steam vulcanization device at a temperature of 100°C for 30 minutes.

[0053] (5) Rinse the vulcanized product with water, dry it, cut samples and test them.

[0054] The sponge fine material dispersion is prepared by the following steps:

[0055] S1: The sponge waste is cleaned and dried before being crushed. The moisture content of the material before crushing is 1.5%, and the particle size after crushing is 10 μm.

[0056] S2: 40 parts by weight of sponge crushed material, 0.6 parts by weight of polyoxyethylene sorbitan monolaurate, 3 parts by weight of sodium methylenebis(vinyl)sulfonate and 57 parts by weight of water are prepared into a sponge fine material dispersion liquid. The pH of the sponge fine material dispersion liquid is 9.8±0.1.

[0057] The sample properties in Example 3 are as follows: density is 88kg / m 3 , 40% indentation hardness is 86N, tensile strength is 70kPa, ball drop resilience is 60%, and compression permanent deformation rate is 13%.

[0058] Example 4

[0059] This embodiment provides a method for preparing a latex sponge product, comprising the following steps:

[0060] (1) Using an automated batching system to prepare ingredients: 100 kg of natural latex, 0.2 kg of potassium pyrophosphate, 6 kg of sulfur dispersion, 4 kg of potassium oleate, and 1.5 kg of potassium ricinoleate are added to a aging reactor for high-speed dispersion, mixing, and aging. The aging temperature is strictly controlled to be 35° C. to ensure that each dispersion is fully mixed and a aging reaction occurs at the set temperature. The pH of the entire aging system is adjusted to 9.8±0.1 and the viscosity is 800-1000 mPa.s.

[0061] (2) When the ripening time is 12 hours, the ripened latex is transported to the foaming machine for foaming. At this time, the rotation speed of the foaming disk is 600r / min, and the ripened latex flow rate is 600g / min.

[0062] (3) Waste rubber fine material, zinc oxide and hardener are introduced at flow rates of 75 g / min, 36 g / min and 30 g / min respectively.

[0063] (4) The foamed latex is directly filled into the mold and vulcanized by a steam vulcanization device at a temperature of 100°C for 30 minutes.

[0064] (5) Rinse the vulcanized product with water, dry it, cut samples and test them.

[0065] The sponge fine material dispersion is prepared by the following steps:

[0066] S1: The sponge waste is cleaned and dried before crushing. The moisture content of the material before crushing is 1.5%, and the particle size after crushing is 12 μm.

[0067] S2: 40 parts by weight of sponge crushed material, 0.4 parts by weight of polyoxyethylene sorbitan monolaurate, 2 parts by weight of sodium methylenebis(vinyl)sulfonate and 58 parts by weight of water are prepared into a sponge fine material dispersion liquid. The pH of the sponge fine material dispersion liquid is 9.8±0.1.

[0068] The sample properties in Example 4 are as follows: density is 84kg / m 3 , 40% indentation hardness is 82N, tensile strength is 86kPa, ball drop resilience is 65%, and compression permanent deformation rate is 8%.

[0069] By comparison, it is found that the structure of the sample in Example 4 and the blank sample in Example 1 is as follows Figure 1 As shown, the performance is close and can fully meet daily needs. Therefore, the method and process for recycling latex waste provided by the present invention meet actual needs, are economical and environmentally friendly, and can be promoted and applied.

[0070] In summary, the above embodiments are only examples of the preferred embodiments of the present invention and do not include all the implementation scopes of the invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be based on the scope defined in the claims.

Claims

1. A method for preparing a latex sponge product, characterized in that: The steps include: (1) Using an automated batching system to prepare ingredients: 100 kg of natural latex, 0.2 kg of potassium pyrophosphate, 6 kg of sulfur dispersion, 4 kg of potassium oleate, and 1.5 kg of potassium ricinoleate are added to a aging reactor for high-speed dispersion, mixing, and aging. The aging temperature is strictly controlled to be 35° C. to ensure that each dispersion is fully mixed and a aging reaction occurs at the set temperature. The pH of the entire aging system is adjusted to 9.8±0.1 and the viscosity is 800-1000 mPa.s. (2) When the ripening time is 12 hours, the ripened latex is transported to the foaming machine for foaming. At this time, the rotation speed of the foaming disk is 600 r / min, and the ripened latex flow rate is 600 g / min; (3) introducing waste rubber fines, zinc oxide and hardener at flow rates of 75 g / min, 36 g / min and 30 g / min respectively; (4) directly filling the foamed latex into the mold and vulcanizing it in a steam vulcanization device at a temperature of 100° C. for 30 min; (5) Rinse the vulcanized product with water, dry it, cut samples and test them; The sponge fine material dispersion is prepared by the following steps: S1: The sponge waste is washed and dried before crushing. The moisture content of the material before crushing is 1.5%, and the particle size after crushing is 12 μm; S2: 40 parts by weight of sponge crushed material, 0.4 parts by weight of polyoxyethylene sorbitan monolaurate, 2 parts by weight of sodium methylene bisnaphthalene sulfonate and 58 parts by weight of water are prepared into a sponge fine material dispersion, wherein the pH value of the sponge fine material dispersion is 9.8±0.1; The properties of the obtained samples are as follows: density is 84kg / m 3 , 40% indentation hardness is 82N, tensile strength is 86kPa, ball drop resilience is 65%, and compression permanent deformation rate is 8%.

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