PVC deodorant and low-odor PVC composition

Abstract

The invention discloses a PVC (polyvinyl chloride) deodorant and a low-odor PVC composition, and belongs to the technical field of PVC deodorant components. A PVC deodorant in the prior art is low in absorption efficiency, easy to release and large in addition amount. The preparation method comprises the following steps: 1) dispersing zeolite and zinc diricinoleate in a benign solvent of zinc diricinoleate, and uniformly mixing to obtain a dispersion liquid; 2) adding an adhesive, controlling the temperature at 60-70 DEG C, and stirring for 1-2 hours; (3) adding stearic acid, and uniformly mixing; and 4) filtering, washing and drying to obtain the deodorant. Through cooperation of zeolite and zinc diricinoleate and a specific preparation method, the efficiency of adsorbing volatile substances by the deodorant is effectively improved, the combination stability of zinc diricinoleate and the volatile substances is improved, and stearic acid and the adsorbed volatile substances are subjected to esterification reaction, so that the adsorption efficiency of the deodorant is improved. The deodorization efficiency and the deodorization stability can be 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. The common method to eliminate the odor in PVC formula is to use high temperature resistant, low volatility, low odor plasticizers, or to add molecular sieves, deodorants, masking agents, etc. to reduce the irritating odor in PVC. Experiments have shown that the odor of polyvinyl chloride products is a large proportion of the odor of the entire product. Deodorants can only cover up the odor, but cannot remove it.

[0003] Patent CN115109422A discloses a deodorant for rubber and plastics, which uses a plant-based long-acting bactericidal deodorant in combination with zeolite powder. The plant-based long-acting bactericidal deodorant reacts chemically with odor-producing substances such as benzene series, aldehydes, nitrogen hydrides, sulfides, carbon oxides, etc., and the zeolite powder is porously adsorbed, thereby achieving a deodorizing effect on different odor components. However, the deodorant disclosed in the patent has complex ingredients, especially the plant-based long-acting bactericidal deodorant contains a variety of plant extracts, which may reduce compatibility with plastic products. On the other hand, the preparation method is complex, and the material and process costs are relatively high. In addition, the deodorizing efficiency of the reaction deodorizing method is low, and the amount added is large when used in PVC.

[0004] Patent CN201210408860.X provides a low-odor PVC composition and its preparation method and use. The composition is based on 100 parts by weight of PVC and other components in the following weight ratios: PVC 100, polyester plasticizer 60-80, stabilizer 4-6, lubricant 0.6-1.2, and the main component is ricinoleic acid zinc first odor absorber 2-6. Although the deodorizing component ricinoleic acid zinc used in this technical means can absorb certain odors, it has poor fixing ability and low absorption efficiency. It will still release odors in a harsh environment such as high temperature or over time, and the amount added is large. 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 deodorant 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 in that: the following preparation method is adopted: 1) Zeolite and zinc ricinoleate are dispersed in a benign solvent of zinc ricinoleate and mixed evenly to obtain a dispersion; 2) Add adhesive, control the temperature at 60~70℃ and stir for 1~2h; 3) Add stearic acid and mix well; 4) Filter, wash and dry to obtain the deodorant.

[0007] The zinc ricinoleate is loaded on the porous surface of the zeolite by combining zeolite with zinc ricinoleate through a specific preparation method, thereby synergistically enhancing the adsorption efficiency and absorption stability of zinc ricinoleate and ensuring the stable adsorption of volatile substances, especially alcohols; the adhesive improves the loading stability of zeolite and zinc ricinoleate and promotes the deodorization reaction of the adsorbed volatile substances, especially alcohols, with stearic acid.

[0008] 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.

[0009] Preferably, the benign solvent for zinc ricinoleate in step 1) is an alcohol solvent, which is easy to remove in the subsequent preparation process, and is more preferably ethanol, which is easy to remove and has lower cost.

[0010] 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 combination reaction of zinc ricinoleate and zeolite.

[0011] 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.

[0012] 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.

[0013] Preferably, the weight ratio of the zeolite, zinc ricinoleate and zinc stearate is 1:2-3:2-3.

[0014] Preferably, the drying in step 3) is carried out in a vacuum drying oven at 80-90° C. until constant weight is reached.

[0015] A low-odor PVC composition, based on 100 parts by weight of PVC resin, further comprises 40-45 parts of DOP, 5-10 parts of epoxidized soybean oil and 5-7 parts of the above-mentioned PVC deodorant.

[0016] Preferably, the preparation method comprises the following steps: 1) PVC resin, DOP, epoxy soybean oil and PVC deodorant are heated and mixed; 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.

[0017] Compared with the prior art, the present invention has the following beneficial effects: by using the combination of zeolite and zinc ricinoleate and by a specific preparation method, the zinc ricinoleate is stably loaded in the complex pores of the zeolite, which can effectively improve the efficiency of the deodorant in adsorbing volatile substances and improve the binding stability of zinc ricinoleate and volatile substances. The binder improves the binding stability between the zeolite and other components and can catalyze the esterification reaction between stearic acid and the adsorbed volatile substances during the irradiation process during use, thereby further improving the deodorization efficiency and deodorization stability. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with the embodiments, and Embodiment 1 is the best embodiment of the present invention.

[0019] 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.

[0020] The content of volatile organic components of PVC resin and the corresponding odor characteristics are shown in Table 1 below.

[0021] Table 1 S-1000M quantitative results .

[0022] Example 1 A PVC deodorant is prepared by the following method: 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.

[0023] 2) Add 25g of titanate coupling agent, control the reaction temperature at 60~70℃, and stir for 1h.

[0024] 3) Add 2kg stearic acid and mix well.

[0025] 4) After filtering and washing, the product was placed in a vacuum drying oven at 85°C and dried to constant weight to obtain deodorant A1.

[0026] Example 2 A PVC deodorant is prepared based on Example 1, wherein the 4A zeolite in step 1) is replaced by natural clinoptilolite, and other conditions are the same as those in Example 1, to obtain a deodorant A2.

[0027] Example 3 A PVC deodorant is prepared by replacing the adhesive titanate coupling agent with a silane coupling agent on the basis of Example 1, and other conditions are the same as those of Example 1, thereby obtaining a deodorant A3.

[0028] Comparative Example 1 A PVC deodorant is prepared by setting the dosage of 4A zeolite to 3 kg on the basis of Example 1, and not adding zinc ricinoleate. Other conditions are the same as those of Example 1, thereby obtaining deodorant B.

[0029] Comparative Example 2 A PVC deodorant is prepared by setting the dosage of zinc ricinoleate to 3 kg on the basis of Example 1, and not adding 4A zeolite. Other conditions are the same as those of Example 1, and a deodorant C is obtained.

[0030] Comparative Example 3 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 and washed, and then the product is placed in a vacuum drying oven at 85° C. and dried to constant weight to obtain a deodorant D.

[0031] Performance Testing The PVC deodorants obtained in the above comparative examples and examples are used to prepare low-odor PVC compositions. The preparation method of the low-odor PVC composition comprises the following steps: 1) PVC resin, DOP, epoxy soybean oil and PVC deodorant are heated and mixed; 2) Add the modified component, mix evenly at 180-190° C., cool to 120-130° C., extrude and granulate using a conical twin-screw extruder, and dry for 6 hours to obtain a low-odor PVC composition.

[0032] 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 formulas of the PVC compositions are shown in Table 2 below.

[0033] Table 2 PVC composition formula .

[0034] The above PVC compositions were tested for performance: the main instrument for analyzing the odor composition of PVC resin is gas chromatography-mass spectrometry (GC-MS), and the odor capture adopts the solid headspace method, and the solid headspace sampling technology is static headspace. Headspace sampling analysis is an analysis of the vapor in equilibrium above a solid sample in a sealed container. In the actual headspace sampling analysis, the sample is encapsulated in a closed sample bottle, placed in a constant temperature oven and heated to a preset temperature. When the solid phase and the gas phase reach equilibrium, a certain amount of vapor is transported to the chromatographic column in the gas chromatograph for analysis. When using this technology, only volatile substances enter the chromatographic column, and the less volatile substances remain in the sample bottle. The headspace method obtains sample component information by analyzing the gas phase related to the sample to be tested.

[0035] The headspace equilibrium temperature has a great influence on the analysis of volatile components. The higher the temperature, the more volatiles can enter the gas phase from the solid phase, increasing the vapor partial pressure of the organic component and the response value. However, too high an equilibrium temperature will cause the PVC to decompose quickly and affect the experiment. The vertical coordinate volatile response value of the GC-MS test results has no unit of measurement. Its size is directly proportional to the concentration or amount of the volatile molecules being tested. 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 to 90°C.

[0036] 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, a test standard for the odor of interior materials for cars, which is a grading standard for judging the odor of rubber and plastic materials.

[0037] The grading criteria are shown in Table 3 below.

[0038] Table 3 Odor classification criteria .

[0039] The performance test results of the above PVC compositions are shown in Table 4 below.

[0040] Table 4 Odor performance test results of PVC compositions .

[0041] In addition, the above PVC composition was made into a medical nasal oxygen tube (after 15 kGy irradiation), and the product performance test is shown in Table 5 below.

[0042] Table 5 Product performance test results .

[0043] The above is only a preferred embodiment of the titanate coupling agent of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A PVC deodorant, characterized in that: The following preparation method is adopted: 1) Zeolite and zinc ricinoleate are dispersed in a benign solvent of zinc ricinoleate and mixed evenly to obtain a dispersion; 2) Add adhesive, control the temperature at 60~70℃ and stir for 1~2h; 3) Add stearic acid and mix well; 4) Filter, wash and dry to obtain the deodorant.

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 adhesive in step 2) is a titanate coupling agent.

6. The PVC deodorant according to claim 1, characterized in that: The weight of the binder in step 2) is 2-3% of the weight of the zeolite.

7. The PVC deodorant according to claim 1, characterized in that: The weight ratio of the zeolite, zinc ricinoleate and zinc stearate is 1:2-3:2-3.

8. 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. until constant weight is reached.

9. A low-odor PVC composition, characterized in that: Based on 100 parts by weight of the PVC resin, 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 8.

10. The low-odor PVC composition according to claim 9, characterized in that: The preparation method comprises the following steps: 1) PVC resin, DOP, epoxy soybean oil and PVC deodorant are heated and mixed; 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.