CN111849032A

CN111849032A - Low-ammonia foaming promoter and preparation method thereof, foaming material and preparation method thereof

Info

Publication number: CN111849032A
Application number: CN202010603730.6A
Authority: CN
Inventors: 胡宗贵; 董建平; 张之文; 黄永明; 朱桂生; 马克和; 刘玲; 唐丽
Original assignee: JIANGSU SOPO (GROUP) CO Ltd; Jiangsu Sopo Engineering Technology Co ltd; JIANGSU SOPO CHEMICAL CO LTD
Current assignee: JIANGSU SOPO (GROUP) CO Ltd; Jiangsu Sopo Engineering Technology Co ltd; JIANGSU SOPO CHEMICAL CO LTD
Priority date: 2020-06-29
Filing date: 2020-06-29
Publication date: 2020-10-30
Anticipated expiration: 2040-06-29
Also published as: CN111849032B

Abstract

The invention relates to a low-ammonia foaming promoter and a preparation method thereof, and a foaming material and a preparation method thereof. The low-ammonia foaming accelerant comprises the following components in parts by weight: 5-20 parts of zinc oxide, 10-25 parts of zinc stearate and 55-85 parts of zinc sulfate. The invention directly utilizes the accelerant to eliminate the irritant ammonia gas generated by the thermal decomposition of azodicarbonamide in the production of the foaming material, thereby reducing the harm to the human body; the invention can eliminate the irritant ammonia gas generated by the thermal decomposition of the azodicarbonamide by using the accelerator which is necessary in the production process of the foaming material, thereby obtaining the high-quality foaming product without ammonia smell by using the azodicarbonamide which has high cost performance and stable foaming effect as the foaming agent, and being beneficial to the cost control of the manufacturing of the foaming material without searching other foaming agent substitutes which have high price and low foaming efficiency from the market and independently adding the ammonia remover; in addition, the existing mature production process of the foaming material is not required to be adjusted, and the operation, implementation and popularization are easy.

Description

Low-ammonia foaming promoter and preparation method thereof, foaming material and preparation method thereof

Technical Field

The invention relates to the field of material molding, in particular to a low-ammonia foaming promoter and a preparation method thereof, a foaming material and a preparation method thereof.

Background

The foaming agent azodicarbonamide is a plastic foaming agent with high cost performance, high gas evolution and most extensive application. The foaming agent azodicarbonamide is added into plastics such as polyvinyl chloride, polyethylene, ethylene vinyl acetate, polypropylene and the like, and is heated to decompose the foaming agent azodicarbonamide to generate gas, so that various heat-insulating, sound-insulating and shock-buffering foaming materials with light specific gravity and good elasticity can be obtained, such as slippers, soles, insoles, plastic wallpaper, artificial leather, child crawling mats, yoga mats and the like.

Because azodicarbonamide has high decomposition temperature, in order to match with the curing and forming speed of plastics, accelerators such as zinc oxide, zinc stearate, urea and the like are usually added in the processing process to adjust the decomposition temperature of the foaming agent, but the decomposition of the azodicarbonamide as the foaming agent generates tasteless gases such as nitrogen, carbon monoxide and carbon dioxide and simultaneously generates a large amount of irritant ammonia. Ammonia gas has pungent smell, and can cause lacrimation, pharyngalgia, hoarseness, cough, chest distress, dyspnea, dizziness, headache, nausea, emesis, debilitation and other symptoms after a large amount of ammonia gas is inhaled, and with the attention of people to health, the reduction of ammonia gas content in the product also becomes the focus in the industry.

In order to solve the problem of ammonia gas in foamed products, some domestic manufacturers adopt 4, 4-oxybis-benzenesulfonyl hydrazide (OBSH) as a foaming agent to replace azodicarbonamide, but the foaming agent has low gas evolution, large addition and high price, so that the production cost cannot be accepted by the market.

In the industry, the equivalent amount of the ammonia remover is added in the processing process to react with the generated ammonia gas, so that the foamed product is tasteless, and the foamed product has higher production cost compared with the conventional production due to large addition amount.

In addition, some accelerators have moisture absorption defects, are easy to absorb moisture in the environment to agglomerate and agglomerate, so that the plastic foaming process has large pore defects and unstable product quality.

Disclosure of Invention

Therefore, it is necessary to provide a low-ammonia foaming promoter and a preparation method thereof, a foaming material and a preparation method thereof, aiming at the problems that the low-ammonia foaming material product is high in production cost, unstable in foaming quality and easy to generate large-pore defects.

A low-ammonia foaming promoter comprises the following components in parts by weight: 5-20 parts of zinc oxide, 10-25 parts of zinc stearate and 55-85 parts of zinc sulfate.

In one embodiment, the composition comprises the following components in parts by weight: 5 parts of zinc oxide, 10 parts of zinc stearate and 85 parts of zinc sulfate.

In one embodiment, the zinc sulfate is zinc sulfate monohydrate. The zinc sulfate monohydrate has less water content, zinc stearate coats the surface of zinc sulfate to isolate the zinc sulfate from the external environment, and the zinc sulfate monohydrate-containing foaming promoter and the foaming agent azodicarbonamide are added into plastic, so that the phenomenon that the pore diameter of a pore is increased due to water volatilization in the reaction process is basically avoided, the defect of macropores of the product is overcome, the foaming pore diameter is small, fine, dense and uniform, the plastic foaming product has higher and more stable quality, and the added value of the product is higher.

A preparation method of a low-ammonia foaming promoter comprises the following steps of mixing zinc oxide, zinc stearate and zinc sulfate according to a ratio of 5-20: 10-25: and respectively weighing 55-85 in parts by weight, adding into a mixer, and mixing for 5-50 min to obtain the low-ammonia foaming promoter.

A foamed material, comprising: plastic raw materials, a cross-linking agent, azodicarbonamide and the low-ammonia foaming accelerant.

In one embodiment, the proportion of each component is as follows according to parts by weight: 220 parts of plastic raw material, 1.6 parts of cross-linking agent, 8 parts of azodicarbonamide and 3 parts of low-ammonia foaming accelerant.

In one embodiment, the plastic feedstock comprises EVA, LDPE, CaCO ₃One or more of (a).

A preparation method of a foaming material comprises the following steps:

heating the two rollers of the open mill to 120 ℃, and uniformly mixing the plastic raw materials on the two rollers;

adding a cross-linking agent, azodicarbonamide and the low-ammonia foaming accelerant, and uniformly mixing to obtain a sheet;

the sheet is placed in a mold for pressure foaming.

In one embodiment, the sheet is placed in a mold at a mold pressure of 15MPa and a mold temperature of 175 deg.C and a mold depth of 10mm for a heating time of 32 min.

The low-ammonia foaming promoter and the preparation method thereof, the foaming material and the preparation method thereof have at least the following beneficial technical effects:

(1) the zinc ion can be provided, the metal zinc ion has the capability of accepting lone pair electrons, and can accept the lone pair electrons on nitrogen atoms and carbonyl oxygen atoms in the azodicarbonamide of the foaming agent, so that the decomposition temperature of the azodicarbonamide is reduced, and the zinc ion has strong promotion effect on the decomposition of the foaming agent.

(2) The reaction formula of the azodicarbonamide thermal decomposition is as follows: h₂NCON＝NCONH₂→N₂+CO+NH₃+CO₂The added zinc sulfate can perform a complex reaction with the generated ammonia NH3, and the reaction mechanism is as follows:

6NH3+ZnSO₄＝[Zn(NH3)₆]SO₄

2NH3+ZnSO₄+2H₂O＝Zn(OH)₂precipitation of + (NH4)2SO₄，

The products generated by the reaction are tasteless substances, the invention directly utilizes the accelerator necessary in the production process of the foaming material to eliminate the irritant ammonia gas generated by the thermal decomposition of azodicarbonamide, reduces the ammonia amount from the source by changing the decomposition process, tests show that the foaming material prepared by the low-ammonia foaming accelerator has no irritant ammonia smell, detects the ammonia gas content of 17-50ppm, is lower than the safe concentration 100ppm of uncomfortable feeling when people smell the foaming material, and greatly reduces the harm of the irritant smell to human bodies in the production process and the use process compared with the existing products.

(3) In the low-ammonia foaming accelerant prepared by the invention, zinc stearate is used for coating the surface of zinc sulfate, and the zinc sulfate is isolated from the external environment, so that the phenomenon of agglomeration caused by the fact that the zinc sulfate absorbs moisture in the environment can be prevented, the final foamed product has fine and uniform pores and fewer macropore defects, and the product quality is improved.

(4) The invention can eliminate the irritant ammonia gas generated by the thermal decomposition of the azodicarbonamide by using the necessary accelerant in the production process of the foaming material, thereby obtaining the high-quality foaming product without ammonia smell by using the conventional azodicarbonamide with high cost performance and stable foaming effect as the foaming agent, and being beneficial to the cost control of the manufacturing of the foaming material without searching other foaming agent substitutes with high price and low foaming efficiency from the market and independently adding an ammonia remover; in addition, the existing mature production process of the foaming material is not required to be adjusted, the technical transformation cost is low, and the operation, implementation and popularization are easy.

Drawings

FIG. 1 is a schematic view showing the internal structure of a foamed material obtained in comparative example 1;

FIG. 2 is a schematic view showing the internal structure of the foamed material obtained in comparative example 2;

FIG. 3 is a schematic view showing the internal structure of the foamed material obtained in comparative example 3;

FIG. 4 is a schematic view showing the internal structure of the foamed material obtained in comparative example 4.

Detailed Description

The invention will be further explained with reference to the drawings.

In order that the invention may be more fully understood, reference will now be made to the following description. The following is a description of preferred embodiments of the invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Those of ordinary skill in the art will recognize that variations and modifications of the various embodiments described herein can be made without departing from the scope of the invention, which is defined by the appended claims. Moreover, descriptions of well-known functions and constructions may be omitted for clarity and conciseness.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Example 1:

5 parts of zinc oxide, 10 parts of zinc stearate and 85 parts of zinc sulfate monohydrate are stirred in a mixer for 10 minutes by weight to prepare the uniformly mixed low-ammonia foaming promoter.

Example 2:

5 parts of zinc oxide, 10 parts of zinc stearate and 85 parts of zinc sulfate hexahydrate are stirred in a mixer for 10 minutes by weight to prepare the uniformly mixed low-ammonia foaming promoter.

Example 3:

according to the weight, 10 parts of zinc oxide, 10 parts of zinc stearate and 80 parts of zinc sulfate hexahydrate are stirred in a mixer for 20 minutes to prepare the uniformly mixed low-ammonia foaming accelerant.

Example 4:

according to the weight, 20 parts of zinc oxide, 25 parts of zinc stearate and 55 parts of zinc sulfate heptahydrate are stirred in a mixer for 20 minutes to prepare the uniformly mixed low-ammonia foaming promoter.

Comparative example 1:

the preparation method comprises the following steps: heating the plastic raw materials EVA, LDPE and CaCO to 120 ℃ by two rollers of an open mill₃Mixing uniformly on a double roller; then adding the low-ammonia foaming accelerant, the cross-linking agent and the foaming agent azodicarbonamide in the embodiment 1, mixing for 3 minutes again, and obtaining slices after uniform mixing; weighing the slices, placing into a mold, and foaming under pressure at 175 deg.C for 32min at a pressure of 15MPa for 10 mm.

After being demoulded, the inner foam pores of the foaming material are fine and uniform (as shown in figure 1), and do not have ammonia smell, and people can not smell the foam pores. Sealing in a glass drier for 24 hr, and detecting ammonia content of 17 ppm.

Comparative example 2:

the preparation method comprises the following steps: heating the plastic raw materials EVA, LDPE and CaCO to 120 ℃ by two rollers of an open mill₃Mixing uniformly on a double roller; then adding the low-ammonia foaming accelerant, the cross-linking agent and the foaming agent azodicarbonamide in the embodiment 2, mixing for 3 minutes again, and obtaining slices after uniform mixing; weighing the slices, placing into a mold, and foaming under pressure at 175 deg.C for 32min at a pressure of 15MPa for 10 mm.

After demolding, the inner cells of the foaming material are basically kept fine and dense, and part of macropores exist (as shown in figure 2); has no ammonia smell, and can not be smelled by human nose. The mixture was sealed in a glass desiccator for 24 hours, and the ammonia gas content was measured to be 18 ppm.

Comparative example 3:

the preparation method comprises the following steps: heating the plastic raw materials EVA, LDPE and CaCO to 120 ℃ by two rollers of an open mill₃Mixing uniformly on a double roller; then adding the low-ammonia foaming accelerant, the cross-linking agent and the foaming agent azodicarbonamide in the embodiment 3, mixing for 3 minutes again, and obtaining slices after uniform mixing; weighing the slices, placing into a mold, and foaming under pressure at 175 deg.C for 32min at a pressure of 15MPa for 10 mm.

Partial large pore defects exist in the inner cells of the foam material after demolding (as shown in figure 3); has no ammonia smell, and can not be smelled by human nose. Sealing in a glass drier for 24 hr, and detecting ammonia content of 50 ppm.

Comparative example 4 (foaming promoter using ordinary zinc oxide):

the preparation method comprises the following steps: heating the plastic raw materials EVA, LDPE and CaCO to 120 ℃ by two rollers of an open mill₃Mixing uniformly on a double roller; then addAdding an accelerant zinc oxide, a cross-linking agent and a foaming agent azodicarbonamide, mixing for 3 minutes again, and uniformly mixing to obtain a sheet; weighing the slices, placing into a mold, and foaming under pressure at 175 deg.C for 32min at a pressure of 15MPa for 10 mm.

The foam cells after demolding are relatively uniform (as shown in FIG. 4), but the ammonia odor is extremely pungent and cannot be tolerated. Sealing in a glass drier for 24 hr, and detecting ammonia gas content of 6000 ppm.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A low-ammonia foaming promoter is characterized by comprising the following components in parts by weight: 5-20 parts of zinc oxide, 10-25 parts of zinc stearate and 55-85 parts of zinc sulfate.

2. The low-ammonia blowing promoter according to claim 1, comprising, in parts by weight: 5 parts of zinc oxide, 10 parts of zinc stearate and 85 parts of zinc sulfate.

3. The low-ammonia blowing promoter of claim 1, wherein the zinc sulfate is zinc sulfate monohydrate.

4. A method for preparing a low-ammonia blowing promoter according to claim 1, characterized in that: zinc oxide, zinc stearate and zinc sulfate are mixed according to the ratio of 5-20: 10-25: and respectively weighing 55-85 in parts by weight, adding into a mixer, and mixing for 5-50 min to obtain the low-ammonia foaming promoter.

5. A foamed material, comprising: a plastic raw material, a crosslinking agent, azodicarbonamide, and a low-ammonia blowing promoter according to any one of claims 1 to 3.

6. The foam material of claim 5, wherein the ratio of the components is, in parts by weight: 220 parts of plastic raw material, 1.6 parts of cross-linking agent, 8 parts of azodicarbonamide and 3 parts of low-ammonia foaming accelerant.

7. The foamed material of claim 5, wherein the plastic material comprises EVA, LDPE, CaCO₃One or more of (a).

8. The preparation method of the foaming material is characterized by comprising the following steps:

adding a cross-linking agent, azodicarbonamide and the low-ammonia foaming promoter as claimed in any one of claims 1 to 3, and uniformly mixing to obtain a sheet;

the sheet is placed in a mold for pressure foaming.

9. The method for preparing a foamed material according to claim 8, wherein the step of placing the sheet in a mold is carried out under a mold pressure of 15Mpa, a mold temperature of 175 ℃, a mold depth of 10mm, and a heating time of 32 min.