PVC odor scavenger and low odor PVC composition

Abstract

The application discloses a PVC deodorant and a low-odor PVC composition, and belongs to the technical field of PVC deodorant ingredients. The PVC deodorant in the prior art has low absorption efficiency, is easy to release, and has a large addition amount. The application adopts the following preparation method: 1) zeolite and zinc ricinoleate are dispersed in a good solvent of zinc ricinoleate, and are uniformly mixed to obtain a dispersion liquid; 2) an adhesive is added, and stirring is carried out at a temperature of 60-70 DEG C for 1-2 hours; 3) stearic acid is added and uniformly mixed; and 4) the deodorant is obtained through filtration, washing and drying. Through the cooperation of zeolite and zinc ricinoleate and a specific preparation method, the absorption efficiency of the deodorant for volatile substances is effectively improved, the combination stability of zinc ricinoleate and volatile substances is improved, and stearic acid and the absorbed volatile substances are subjected to esterification, so that the deodorization efficiency and deodorization stability are further improved.

Description

Technical Field

[0001] The invention discloses a PVC deodorant and a low-odor PVC composition, belonging to the technical field of PVC deodorizing components. Background Art

[0002] The odor of PVC plastic products has become a hot topic of concern. Common methods for eliminating odor in PVC formulations include selecting high-temperature-resistant, low-volatility, and low-odor plasticizers, or reducing the pungent odor by adding molecular sieves, deodorizers, and odor masking agents. Tests have shown that the odor of PVC products is largely due to the heat-induced odor of the resin itself. Deodorizers can only mask the odor, not remove it.

[0003] Patent CN115109422A discloses a deodorizer for rubber and plastics. It uses a plant-based long-lasting bactericidal deodorizer in combination with zeolite powder. The plant-based long-lasting bactericidal deodorizer chemically reacts with odor-producing substances such as benzene series, aldehydes, nitrogen hydrides, sulfides, and carbon oxides. The zeolite powder then adsorbs these substances through its porous structure, thereby deodorizing different odor-producing components. However, the deodorizer disclosed in this patent has complex ingredients, particularly the plant-based long-lasting bactericidal deodorizer, which contains multiple plant extracts, potentially reducing its compatibility with plastic products. Furthermore, the preparation method is complex, resulting in high material and process costs. Furthermore, the reaction-based deodorization method has low deodorization efficiency, and a large dosage is required for application in PVC.

[0004] Patent CN201210408860.X provides a low-odor PVC composition, its preparation method, and its use. The composition, based on 100 parts by weight of PVC, contains the following components in the following proportions: 100 parts PVC, 60-80 parts polyester plasticizer, 4-6 parts stabilizer, 0.6-1.2 parts lubricant, and 2-6 parts first odor absorber, primarily zinc ricinoleate. While zinc ricinoleate, the deodorizing ingredient used in this technique, can absorb certain odors, it has poor retention and low absorption efficiency. It still releases odor in harsh environments such as high temperatures or over time, and requires a large dosage. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a PVC deodorizer and a low-odor PVC composition which have high deodorizing efficiency and are not prone to odor precipitation.

[0006] The technical solution adopted by the present invention to solve the technical problem is: a PVC deodorant, characterized by adopting the following preparation method:

[0007] 1) dispersing zeolite and zinc ricinoleate in a benign solvent for zinc ricinoleate and mixing them uniformly to obtain a dispersion;

[0008] 2) Add adhesive and stir at 60-70℃ for 1-2 hours;

[0009] 3) Add stearic acid and mix well;

[0010] 4) Filter, wash and dry to obtain the deodorant.

[0011] Zeolite and zinc ricinoleate are combined and loaded onto the porous surface of the zeolite through a specific preparation method, thereby achieving synergistic effects, improving the adsorption efficiency and absorption stability of zinc ricinoleate, and ensuring the stable adsorption of volatile substances, especially alcohols. The binder improves the loading stability of the zeolite and zinc ricinoleate, while promoting the reaction of the adsorbed volatile substances, especially alcohols, with stearic acid for deodorization.

[0012] Preferably, the zeolite in step 1) is 4A zeolite. 4A zeolite has a more complex porous structure, is easy to load zinc ricinoleate, and is firmly bonded, and has a large adsorption capacity for volatile substances.

[0013] Preferably, the benign solvent for zinc ricinoleate in step 1) is an alcohol solvent, which is easy to remove in subsequent preparation steps. Ethanol is more preferably used, which is easy to remove and has lower cost.

[0014] Preferably, the volume ratio of the total weight of zeolite and zinc ricinoleate to the solvent in the dispersion of step 1) is 1:5 to 15. The preferred weight-to-volume ratio can ensure the binding reaction between zinc ricinoleate and zeolite.

[0015] Preferably, the adhesive in step 2) is a titanate coupling agent. The titanate coupling agent can also catalyze the esterification reaction between stearic acid and volatile substances.

[0016] Preferably, the weight of the binder in step 2) is 2-3% of the weight of the zeolite, thereby improving the binding stability and binding rate of the zeolite with zinc ricinoleate and stearic acid.

[0017] Preferably, the weight ratio of the zeolite, zinc ricinoleate and zinc stearate is 1:2-3:2-3.

[0018] Preferably, the drying in step 3) is carried out in a vacuum drying oven at 80-90° C. to a constant weight.

[0019] A low-odor PVC composition comprises, based on 100 parts by weight of PVC resin, 40-45 parts of DOP, 5-10 parts of epoxidized soybean oil and 5-7 parts of the above-mentioned PVC deodorant.

[0020] Preferably, the preparation method comprises the following steps:

[0021] 1) Heat and mix PVC resin, DOP, epoxy soybean oil and PVC deodorizer;

[0022] 2) Add the modified component, mix evenly at 180-190°C, cool to 120-130°C, extrude granulate, and dry to obtain a low-odor PVC composition.

[0023] Compared with existing technologies, the present invention offers the following advantages: by combining zeolite with zinc ricinoleate and employing a specific preparation method, the zinc ricinoleate is stably loaded within the complex pores of the zeolite, effectively improving the deodorant's efficiency in adsorbing volatile substances and enhancing the binding stability between zinc ricinoleate and volatile substances. The binder enhances the binding stability between the zeolite and other components and, during irradiation, catalyzes the esterification reaction between stearic acid and the adsorbed volatile substances, further enhancing both deodorization efficiency and stability. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to the embodiments, wherein embodiment 1 is the best embodiment of the present invention.

[0025] In the following examples, the PVC resin is S-1000M, the titanate coupling agent is QX-201, and the modified components are calcium zinc stabilizer CZ-11, external lubricant ZB-74, antioxidant 3114, antioxidant 3014T, and ultraviolet absorber UV531.

[0026] The content of volatile organic compounds in PVC resin and the corresponding odor characteristics are shown in Table 1 below.

[0027] Table 1 S-1000M quantitative results

[0028] .

[0029] Example 1

[0030] A PVC deodorant is prepared by the following method:

[0031] 1) Disperse 1 kg of 4A zeolite and 2 kg of zinc ricinoleate in 15 L of ethanol and mix well to obtain a dispersion.

[0032] 2) Add 25g of titanate coupling agent, control the reaction temperature at 60~70℃, and stir for 1h.

[0033] 3) Add 2kg of stearic acid and mix well.

[0034] 4) After filtration and washing, the product was placed in a vacuum drying oven at 85°C and dried to a constant weight to obtain deodorant A1.

[0035] Example 2

[0036] A PVC deodorant is prepared according to Example 1, wherein the 4A zeolite in step 1) is replaced with natural clinoptilolite, and other conditions are the same as those in Example 1, to obtain deodorant A2.

[0037] Example 3

[0038] A PVC deodorant is prepared by replacing the adhesive titanate coupling agent with a silane coupling agent based on Example 1, with other conditions being the same as those in Example 1, to obtain deodorant A3.

[0039] Comparative Example 1

[0040] A PVC deodorant was prepared by using the same conditions as in Example 1, except that the amount of 4A zeolite was 3 kg and zinc ricinoleate was not added. Deodorant B was obtained.

[0041] Comparative Example 2

[0042] A PVC deodorant was prepared by using the method of Example 1, except that the amount of zinc ricinoleate was 3 kg, 4A zeolite was not added, and other conditions were the same as those of Example 1, to obtain a deodorant C.

[0043] Comparative Example 3

[0044] A PVC deodorant is prepared by the following method: 1 kg of 4A zeolite, 2 kg of zinc ricinoleate, 90 g of a titanate coupling agent, and 2 kg of stearic acid are mixed at once, stirred at 60-70°C for 1 hour, filtered, washed, and then placed in a vacuum drying oven at 85°C for drying to constant weight to obtain deodorant D.

[0045] Performance Testing

[0046] The PVC deodorants obtained in the above comparative examples and examples were used to prepare low-odor PVC compositions. The preparation method of the low-odor PVC composition comprises the following steps:

[0047] 1) Heat and mix PVC resin, DOP, epoxy soybean oil and PVC deodorizer;

[0048] 2) adding the modified component, mixing uniformly at 180-190° C., cooling to 120-130° C., extruding into granules using a conical twin-screw extruder, and drying for 6 hours to obtain a low-odor PVC composition.

[0049] PVC compositions 1 to 5 were prepared using deodorants A1 to A3, and PVC compositions 6 to 7 were prepared using deodorants B, C, and D. The formulations of the PVC compositions are shown in Table 2 below.

[0050] Table 2 PVC composition formula

[0051] .

[0052] Performance testing of the above PVC compositions was conducted: The primary instrument for analyzing the odor composition of PVC resins was a gas chromatography-mass spectrometer (GC-MS). Odor capture was performed using the solid-state headspace method, a static headspace sampling technique. Headspace analysis analyzes the vapors in equilibrium above a solid sample in a sealed container. In actual headspace analysis, the sample is sealed in a sealed vial, placed in a constant-temperature oven, and heated to a preset temperature. When equilibrium is reached between the solid and vapor phases, a certain amount of vapor is transported to the gas chromatograph column for analysis. Using this technique, only volatile substances enter the column, while less volatile substances remain in the sample vial. The headspace method obtains sample composition information by analyzing the vapor phase associated with the sample being tested.

[0053] The headspace equilibrium temperature significantly influences volatile component analysis. Higher temperatures allow more volatiles to enter the gas phase from the solid phase, increasing the vapor pressure of organic components and the response. However, excessively high equilibrium temperatures can lead to rapid decomposition of PVC, hindering experimental performance. The volatile response value on the vertical axis of the GC-MS test results has no unit of measurement; its magnitude is directly proportional to the concentration or amount of the volatile molecules being detected. As the equilibrium temperature increases, the total volatile response value also increases. During the experiment, considering the thermal stability requirements of PVC resin, the equilibrium temperature was set at 90°C.

[0054] The temperature condition of the low-odor radiation-resistant composition of the present invention is also determined to be 90° C., with reference to SMC 30156-2007 Odor Test for Car Interior Materials, which is a grading standard for evaluating the odor of rubber and plastic materials.

[0055] The grading criteria are shown in Table 3 below.

[0056] Table 3 Odor classification criteria

[0057] .

[0058] The performance test results of the above PVC compositions are shown in Table 4 below.

[0059] Table 4 Odor performance test results of PVC compositions

[0060] .

[0061] In addition, the above PVC composition was made into a medical nasal oxygen tube (after irradiation with 15 kGy), and the product performance test is shown in Table 5 below.

[0062] Table 5 Product performance test results

[0063] .

[0064] The above descriptions are merely preferred embodiments of the titanate coupling agent of the present invention and are not intended to limit the present invention in any other manner. Any person skilled in the art may utilize the above-disclosed technical content to modify or modify the above-disclosed technical content into equivalent embodiments. However, any simple modifications, equivalent variations, and modifications to the above-disclosed embodiments that do not depart from the technical content of the present invention and are based on the technical essence of the present invention remain within the scope of protection of the present invention.

Claims

1. A PVC deodorant, characterized by: The following preparation method is adopted: 1) dispersing zeolite and zinc ricinoleate in a benign solvent for zinc ricinoleate and mixing them uniformly to obtain a dispersion; 2) Add adhesive and stir at 60-70℃ for 1-2 hours; 3) Add stearic acid and mix well; 4) filtering, washing, and drying to obtain a deodorant; The binder in step 2) is a titanate coupling agent; the weight of the binder in step 2) is 2-3% of the weight of the zeolite; The weight ratio of the zeolite, zinc ricinoleate and stearic acid is 1:2-3:2-3.

2. The PVC deodorant according to claim 1, characterized in that: The zeolite in step 1) is 4A zeolite.

3. The PVC deodorant according to claim 1, characterized in that: The benign solvent for the zinc ricinoleate in step 1) is an alcohol solvent.

4. The PVC deodorant according to claim 1, characterized in that: The volume ratio of the total weight of zeolite and zinc ricinoleate to the solvent in the dispersion of step 1) is 1 g: 5-15 ml.

5. The PVC deodorant according to claim 1, characterized in that: The drying in step 3) is carried out in a vacuum drying oven at 80-90° C. to a constant weight.

6. A low-odor PVC composition, characterized in that: The composition further comprises 40-45 parts of DOP, 5-10 parts of epoxidized soybean oil and 5-7 parts of the PVC deodorant according to any one of claims 1 to 5, based on 100 parts by weight of the PVC resin.

7. The low-odor PVC composition according to claim 6, characterized in that: The preparation method comprises the following steps: 1) Heat and mix PVC resin, DOP, epoxy soybean oil and PVC deodorizer; 2) Add the modified component, mix evenly at 180-190°C, cool to 120-130°C, extrude granulate, and dry to obtain a low-odor PVC composition.